Arithmetic encoders, arithmetic decoders, video encoder, video decoder, methods for encoding, methods for decoding and computer program

Abstract

Embodiments provide an arithmetic encoder for encoding a plurality of symbols having symbol values, wherein the arithmetic encoder is configured to determine one or more state variable values, which represent statistics of a plurality of previously encoded symbol values, and wherein the arithmetic encoder is configured to derive an interval size information for an arithmetic encoding of one or more symbol values to be encoded on the basis of one or more state variable values which represent statistics of a plurality of previously encoded symbol values. Furthermore, the arithmetic encoder is configured to selectively increase an adaptation speed of one or more of the state variable values for a predetermined number of bins following an initialization of the one or more state variable values; and / or to selectively reduce an adaptation speed of one or more of the state variable values when a predetermined number of bins following an initialization of one or more state variable values has passed; and / or to use a first, comparatively higher adaptation speed for adapting one or more of the state variable values to a probability of encoded symbol values for a first group of bins following an initialization of the one or more state variable values, and to use a second, comparatively lower adaptation speed for adapting one or more of the state variable values to a probability of encoded symbol values for a second group of bins following the first group of bins. Further arithmetic encoders, arithmetic decoders, video encoders, video decoder, methods for encoding, methods for decoding and computer programs are also disclosed which are based on the same concept and on other concepts.

Description

[0001]Arithmetic Encoders, Arithmetic Decoders, Video Encoder, Video Decoder, Methods for Encoding, Methods for Decoding and Computer Program Technical Field Embodiments according to the invention create arithmetic encoders. Further embodiments according to the invention create arithmetic decoders. Further embodiments according to the invention create video encoders. Further embodiments according to the invention create video decoders. Further embodiments according to the invention create methods for encoding a plurality of symbols and methods for decoding a plurality of symbols. Further embodiments according to the invention create corresponding computer programs. Generally speaking, embodiments according to the invention create a context model update method using a finite state machine. Background of the Invention Arithmetic encoding and decoding is proven to be a valuable tool in the encoding and decoding of audio and video contents and also in the encoding of other types of information, like pictures, neural network coefficients and the like. Embodiments of the invention can be used for all of these applications. For example, it is possible to exploit known occurrence probabilities of binary values (e.g., symbols) in a binary sequence representing a video or audio content (or other types of content) to increase encoding efficiency. In particular, arithmetic encoding can deal with varying probabilities of “0”s and “1”s in an efficient manner, and can adapt to changes of the probabilities in a fine-tuned manner. FH240412PEP-2025112831.DOCX However, for arithmetic encoding and decoding to bring an optimal coding efficiency, it is important to have a good information about the probabilities of “0”s and “1”s which well reflects an actual frequency of occurrence. In order to adapt to the probabilities of “0”s and “1”s (or generally, to adapt to probabilities of the symbols to be encoded), a concept is typically used to adjust boundaries of intervals within a total (current) range of values, to obtain an interval sub-division (for example, such that a full range of values is sub-divided into intervals associated with different binary values or groups of binary values). In other words, information about the probabilities of different symbols (like “0”s and “1”s) is used to derive an interval size information (or, equivalently, an interval size value) which describes a width of an interval associated with a symbol (wherein a total interval width may, for example, vary over time depending on the encoding or decoding process, for example, due to an interval re-normalization). Accordingly, there is a need for concepts for the determination of source statistic values (e.g. state variable values) and / or range values (like interval size values) for the interval sub-division (for example, for the sub-division of a total coding interval), which provide a good tradeoff between computational efficiency and liability. Summary of the Invention An embodiment according to the invention creates an arithmetic encoder for encoding a plurality of symbols having symbol values (e.g. binary values), wherein the arithmetic encoder is configured to derive an interval size information (pk, R*pk) for an arithmetic encoding of one or more symbol values to be encoded on the basis of a plurality of state variable values (sik) (which are, for example, associated with a given context mode, indicated by index k), which represent statistics of a plurality of previously encoded symbol values (e.g. a sequence of binary values 0 and 1) with different adaptation time constants, wherein the arithmetic encoder is configured to map a first state variable value (sk1), or a scaled and / or rounded version ( ⌊sk1* ak1 ⌋ ) thereof, using a lookup-table (LUT1) and to map a second state variable value (sk2), or a scaled and / or rounded version ( ⌊sk2* ak2⌋ ) thereof using the lookup-table (LUT1), in order to obtain the interval size information (e.g. pkor FH240412PEP-2025112831.DOCX R*pk) describing an interval size for the arithmetic encoding of one or more symbols to be encoded. This embodiment according to the invention is based on the idea that interval size information can be obtained with particularly good reliability if lookup-table-based mappings are applied to state variable values which are associated with different adaptation time constants. In other words, by applying the same lookup table to two state variable values which describe statistics (for example symbol probabilities) on different time scales, an interval size information can be obtained in an efficient manner (because only one lookup table is needed) but with a good reliability (because statistics on different time scales are considered in the determination of the interval size information). The mapping of the state variable values using the lookup table can be considered as an important and immediate step in the derivation of the interval size information on the basis of the state variable values. Optionally, one or more additional mappings and / or a combination of mapping results may follow the lookup-table-based mapping of the first and second state variable values in the derivation of the interval size information. Optionally, probability values may be obtained as an intermediate quantity using the lookup-table-based mapping of the first state variable value and of the second state variable value. Moreover, different concepts are possible for deriving interval size information from the result of the lookup-table-based mapping of the first state variable value and from the result of the lookup-table-based mapping of the second state variable value. To conclude, this embodiment according to the invention provides for a derivation of the interval size information on the basis of the first state variable value and the second state variable value which uses (at least) two lookup-table-based mappings. Accordingly, the state variable values, which are associated with different adaptation time constants, can be mapped individually, but using a same mapping rule (defined by the lookup table), which keeps a resource demand for the determination of the interval size information reasonably small but still allows for a consideration (for example, weighted consideration) of statistics of (or statistic information about) a plurality of previously handled (e.g., encoded or decoded) symbols obtained with different adaptation time constants or statistics computation time constants. In a preferred embodiment, the arithmetic encoder is configured to map the first state variable value, or the scaled and / or rounded version ( ⌊sk1* ak1 ⌋ ) thereof, onto a first probability value (pk1) using the look-up table, and wherein the arithmetic encoder is FH240412PEP-2025112831.DOCX configured to map the second state variable value, or the scaled and / or rounded version ( ⌊sk2* ak2⌋ ) thereof, onto a second probability value (pk2) using the look-up table, and wherein the arithmetic encoder is configured to obtain a combined probability value (pk) using the first probability value and the second probability value (for example, using a weighted summation or using a weighted averaging). Using such a concept, the combined probability value, which describes a symbol probability (e.g., a probability of a “1” symbol or a probability of a “0” symbol) can be derived easily on the basis of the first state variable value and on the basis of the second state variable value. For example, the first state variable value, which follows previously handled (e.g., encoded or decoded) symbols with a first agility, can be mapped onto the first probability value, and the second state variable value, which follows previously handled (e.g., encoded or decoded) symbols with a second agility, can be mapped efficiently onto the second probability value. Thus, trends of the previously handled symbols occurring on different time scales can be considered, and it is still possible to derive the combined probability value in a very efficient manner. The first and second state variable values allow to track trends of the previously handled symbols with different adaptation time constants, and the mapping of the state variable values onto “partial” probability values (first probability value and second probability value), which contribute to the combined probability value, can be done in a very resource-efficient manner using the above-mentioned concept. In a preferred embodiment, the arithmetic encoder is configured to change the state variable value into a first direction (e.g. to become more positive) if a symbol to be encoded takes a first value (e.g. “1”), and to change the state variable value into a second direction (e.g. to become more negative) if a symbol to be encoded takes a second value (e.g. “0”) which is different from the first value (for example, such that the state variable value can take positive and negative values), wherein the arithmetic encoder is configured to determine an entry of the lookup-table to be evaluated in dependence on an absolute value (skiif ski>0, -skiotherwise) of a respective state variable value (e.g. in dependence on a scaled and rounded version of an absolute value of the state variable value). By using a state variable value which can, for example, take positive and negative values (for example, in dependence on a history of previously handled symbols, and, for example, in a symmetric manner for opposite previously handled symbols), and by selecting an entry of the lookup table in dependence on an absolute value of the respective state variable value, an efficiency of the concept can even be improved. For example, it is no longer FH240412PEP-2025112831.DOCX necessary to have dedicated entries of the lookup table for each possible value (or quantized value) of the state variable value. Rather, it is possible to double-use an entry of the lookup table both for a positive state variable value and for a corresponding negative state variable value (i.e., for “inverse” state variable values having equal absolute values but opposite sign). Consequently, a number of entries of the lookup table can be kept small, and the “symmetry” of the determination of the interval size information with respect to opposite previously handled symbols can be exploited. In a preferred embodiment, the arithmetic encoder is configured to set a first probability value (pk1) to a value provided by the lookup table (e.g. to ^^^^1[⌊ ^^^^^^ ∙ ^^^^^^⌋] ) if the first state variable value takes a first sign (e.g. a positive sign), and wherein the arithmetic encoder is configured to set the first probability value (pk1) to a value obtained by subtracting a valueprovided by the lookup table (e.g. to ^^^^ ^^^^ ∙ ^^^^ ⌋]) from a predetermined value (e.g.1) if the first state variable value takes a second sign (e.g. a negative sign). Using such a mechanism, a number of entries of the lookup table can be kept small (for example, because an entry of the lookup table is only selected on the basis of an absolute value of the respective state variable value), while it is still possible to obtain “complimentary” probability values for opposite signs of the respective state variable value. Thus, a high degree of resource-efficiency and a low computational complexity is achieved for the determination of the probability values. In a preferred embodiment, the arithmetic encoder is configured to determine two or more probability values pki according to wherein LUT1 is a lookup-table containing probability values; wherein ⌊ . ⌋ is a floor operator; wherein skiis an i-th state variable value; and wherein akiis a weighting value associated with the i-th state variable value (for example, a weighting value that adapts a number range of the i-th state variable value to a number of entries of the lookup-table). It has been found that such a computation is computationally efficient and keeps a resource- demand reasonably small. FH240412PEP-2025112831.DOCX In a preferred embodiment, the arithmetic encoder is configured to determine two or more probability values pkiaccording to wherein LUT1 is a lookup-table containing probability values; wherein ⌊ . ⌋ is a floor operator; wherein ski is an i-th state variable value; and wherein aki is a weighting value associated with the i-th state variable value (for example, a weighting value that adapts a number range of the i-th state variable value to a number of entries of the lookup-table). It has been found that such a computation is advantageous in some circumstances, depending on the actual number representation. In particular, the floor operator is applied to the same operand irrespective of a sign of the state variable value. In particular, it is not necessary to remove the sign of the operand of the floor operator, which saves some computational complexity. Rather, a negation is only applied to the result of the floor operator, which is typically an integer value. Accordingly, the complexity for applying the negation operator is particularly small. In other words, the concept as described herein also brings along a particularly low complexity. In a preferred embodiment, the arithmetic encoder is configured to obtain a combined probability value pkon the basis of a plurality of probability values pkiaccording to wherein N is a number of probability values considered (and may be equal to a number of state variable values considered); and wherein bki is a weighting value (for example, a weighting factor that controls an influence of individual state variable values onto the combined probability value) (wherein bki are preferably integer-valued potencies of von 2, and wherein a ratio between two different bki is preferably an integer-valued potency of 2). By applying different weighting to the probability values obtained on the basis of different state variable values, the different impact of short-term statistics and long-term statistics onto the combined probability value can be considered, and a particularly meaningful combined probability value can be obtained. FH240412PEP-2025112831.DOCX In a preferred embodiment, the arithmetic encoder is configured to map the first state variable value, or the scaled and / or rounded version ( ⌊sk1* ak1⌋ ) thereof, onto a first subinterval width value (R*pk1) using a two-dimensional look-up table, entries of which are addressed in dependence on the first state variable value (e.g. to determine a first lookup table entry coordinate, e.g. using a probability index i) and in dependence on a coding interval size information (e.g. R, or an index j derived from R) describing a size of a coding interval of the arithmetic encoding before an encoding of a symbol (e.g. to determine a second lookup table entry coordinate), wherein the arithmetic encoder is configured to map the second state variable value, or the scaled and / or rounded version ( ⌊sk2* ak2 ⌋ ) thereof, onto a second subinterval width value (R*pk2) using the two-dimensional look-up table, entries of which are addressed in dependence on the second state variable value (e.g. to determine a first lookup table entry coordinate) and in dependence on a coding interval size information (e.g. R) describing a size of a coding interval of the arithmetic encoding before an encoding of a symbol (e.g. to determine a second lookup table entry coordinate), wherein the arithmetic encoder is configured to obtain a combined subinterval width value using the first subinterval width value and the second subinterval width value (for example, using a weighted summation or using a weighted averaging). By using such a two-dimensional lookup table, which reflects the multiplication of a plurality of different probability values with a plurality of different interval size values, a computational complexity can be reduced since a multiplication operation can be saved. For example, one of the two indices (row index and column index) which designates the entries of the two- dimensional lookup table is defined by a respective state variable value (or a scaled and / or rounded version thereof), and a second index is determined by a current (total) coding interval size. Thus, on the basis of the first index and the second index, an element (entry) of the two dimensional lookup table can be uniquely identified, and the identified element typically reflects a product of a probability value associated with the respective state variable value and of a coding interval size associated with the second table index. Consequently, by spending some memory, which may be a read-only memory in some cases, for the two- dimensional lookup table, an execution of a multiplication operation may be saved, which may be advantageous in terms of computational resources and also in terms of energy consumption. In a preferred embodiment of the arithmetic encoder, the two-dimensional look-up table is representable as a dyadic product between a first one-dimensional vector (forming a one- FH240412PEP-2025112831.DOCX dimensional look-up table) entries of which comprise probability values for different value intervals of a value domain for the first and second state variable values, or the scaledand / or rounded version ( ⌊sk* ak ⌋; |^^^^| ∙ ^^^^) thereof, and a second one-dimensional vector(^^^^2(^^)) entries of which comprise quantization levels for the coding interval size information. By using such a three dimensional lookup table, a multiplication operation between different pairs of probability values and coding interval sizes can be reflected by the table. Accordingly, by selecting an appropriate element of the two dimensional lookup table, the execution of a multiplication operation can be saved. Furthermore, the entries of the two- dimensional lookup table can be obtained in a very simple manner using such an approach. In a preferred embodiment of the arithmetic encoder, elements of the two-dimensional lookup-table (RangTabLPS) are defined on the basis of a base lookup table (Base TabLPS), wherein a first group (or block; e.g. an “upper half”) of the elements of the two-dimensional lookup-table are identical to elements of the base lookup-table or are rounded versions of elements of the base lookup table, and wherein a second group, (or block; e.g. a “lower half”) of the elements of the two-dimensional lookup-table are scaled and rounded versions of elements of the base lookup-table. By using such an approach, an approximately exponential increase or decay of the elements of the two dimensional lookup table can be obtained. For example, by defining the elements of the two dimensional lookup table such that a second group of the elements of the two dimensional lookup table are, substantially (for example, except for deviations caused by a rounding) a scaled version of the elements of the first group of elements of the two dimensional lookup table, a highly uniform two dimensional lookup table can be obtained. Also, it should be noted that it is easily possible to obtain the elements of the two dimensional lookup table using such an approach. In a preferred embodiment of the arithmetic encoder, the second group of elements of the two-dimensional lookup-table are right-shifted versions of elements of the base-lookup table By using such an approach, the elements of the two dimensional lookup table can be obtained in a particularly efficient manner, since right-shifting operations can be performed very easily. Also, the right-shifting operations cause an appropriate scaling and may also perform a rounding operation in a very efficient manner. FH240412PEP-2025112831.DOCX In a preferred embodiment of the arithmetic encoder, a probability index (Qp2(pLPS) or i) ) determines whether an element of the first group of elements of the two-dimensional lookup table or an element of a second group of elements of the two-dimensional lookup table is evaluated, wherein a first range (for example, between 0 and µ-1) of probability indices (which are, for example, obtained by quantizing a probability value, e.g. pLPS) is associated with elements of the first group of elements, and wherein a second range (for example, larger than or equal to µ) of probability indices (which are, for example, obtained by quantizing a probability value, e.g. pLPS, e.g. using a quantization function Qp2(.)) is associated with elements of the second group of elements; By using such a concept, a distinction whether an element of the first group of elements or an element of the second group of elements should be used, can be made in dependence on the probability index, which may, for example, be based on the respective state variable value. For example, the probability index (which may, for example, be defined by a probability of a least probable symbol, or by an integer index value) may, for example, be derived on the basis of the respective state variable value using a mapping. For example, the first probability value obtained using a mapping of the first state variable value, or the second probability value obtained using a mapping of the second state variable value, may be used to determine which element of the two dimensional lookup table should be evaluated (and, in particular, determines whether an element of the first group of elements of the two dimensional lookup table or an element of the second group of elements of the two dimensional lookup table is evaluated). Also, using this concept, it is possible to determine the respective element of the two dimensional lookup table “on the fly” on the basis of the base lookup table, a number of elements of which is smaller than a number of table elements which can be addressed by the probability index and a coding interval size index. In a preferred embodiment of the arithmetic encoder, a division residual (i%µ) of a division between the probability index (i) and a first size value (e.g. µ; wherein the size value, for example, describes an extension of the base lookup table in a first direction) and an interval size index (which may, for example, be obtained on the basis on an interval size information R, for example using a quantization operation Qr2(.); for example, j) determine which element of the base lookup table is used to obtain the element of two-dimensional lookup table. FH240412PEP-2025112831.DOCX By using such a concept, an appropriate element of the base lookup table can be selected, even though an extension of the base lookup table in a first direction is smaller than a number of possible probability index values. By evaluating a divisional residual of a division between the probability index and a first size value, which may describe an extension of the base lookup table in the first direction, elements of the base lookup table can be reused for two or more different probability index values (which may, for example, differ by the first size value). Consequently, an entry of the base lookup table may be used twice, for example, using a different scaling, for two probability index values which differ by the first size value. Accordingly, it can be exploited that the two-dimensional lookup table typically describes an evolution over the probability index values, wherein an evolution in a second range of probability index values is a scaled version (for example, accept for rounding effects) when compared to an evolution in a first range of probability index values. In a preferred embodiment, the arithmetic encoder is configured to obtain an element of the two-dimensional lookup-table (RangTabLPS) according to RangeTabLPS[i][j]=Scal(BaseTabLPS[i%µ][j) , ⌊i / µ⌋); wherein BaseTabLPS is a base lookup table of dimension µ x λ; wherein i is a table index associated with a probability information; wherein j is a table index associated with an interval size information (e.g. describing a current coding interval size); wherein % is a division residual operation; wherein / is a division operation; wherein Scal (x,y) is a scaling function (for example, defined as Scal (x,y)= ⌊x*a-by⌋, wherein ⌊. ⌋ is a floor operation, wherein a is preferably a constant larger than or equal to 2, and wherein b is preferably a constant larger than or equal to 1, and wherein the scaling function is preferably implemented using a shift-to-the -right bit shift operation, wherein y determines whether and by how many bits a shift-to-the-right of x is performed). By using such an approach, interval size information, which may be defined by a result of the scaling function or scaling operation, may be obtained in a particularly memory-efficient manner. For example, the “BaseTabLPS” lookup table may be particularly small, since its first dimension μ is typically smaller than a range of values of the table index ^^ associated with the probability information, and since its second dimension λ may be equal to the number of possible different interval sizes described by the interval size information. Furthermore, the scaling function may be implemented in a particularly efficient manner, FH240412PEP-2025112831.DOCX since the number of different scaling factors, defined by the floor-operation of the quotient of ^^ and μ, is relatively small. For example, if the range of the division between ^^ and μ is between 0 and a maximum value smaller than 2, only two different scaling operations may be performed. For example, only two, three or four different scaling options may exist (depending on the quotient between ^^ and μ), and these scaling options may be implemented efficiently using multiplications with only a few predetermined values or even using mere shift operations. In a preferred embodiment of the arithmetic encoder, elements of the two-dimensional lookup-table (RangTabLPS) are defined on the basis of a probability table (probTabLPS), wherein the probability table describes interval sizes for a set of a plurality of probability values (for example, represented by indices i) and for a given (reference) coding interval size, and wherein elements of the two-dimensional lookup-table for a probability value which is not in the set of a plurality of probability values and / or for a coding interval size which is different from the given coding interval size are derived from the probability table using a scaling. Using such an approach, it can be exploited that different interval sizes are often related with each other by a scaling, which is dependent on a difference between associated probability values and / or on a difference between associated coding interval sizes. Wording it differently, if the two dimensional lookup table does not comprise an element which fits the currently considered probability value and / or the currently considered coding interval size, an appropriate interval size can still be obtained, wherein another element of the two dimensional lookup table is scaled accordingly (for example, in dependence on the currently considered probability value and / or in dependence on the currently considered coding interval size). In a preferred embodiment of the arithmetic encoder, elements of the two-dimensional lookup-table are obtained using a (multiplicative) first scaling of a selected element (probTabLPS[i%µ]) of the probability table in dependence on the coding interval size (R), and using a second scaling of a result of the first scaling in dependence on whether an element associated with a current probability value (designated by index i) is included in the set of probability values or not (e.g. in dependence on whether the current probability value lies within a range of probability values covered by the probability table or not). FH240412PEP-2025112831.DOCX Accordingly, elements of the two dimensional lookup table can be obtained “on the fly” using an appropriate entry of the probability table and using an appropriate scaling, wherein the “probability table”, which is evaluated, is typically significantly smaller than the two dimensional lookup table. In other words, on the basis of the two indices addressing an element of the two dimensional lookup table, an appropriate element of the probability table is selected and scaled. However, in many situations, such a concept provides an improved tradeoff between memory demand and computational complexity. In a preferred embodiment of the arithmetic encoder, a division residual (i%µ) of a division between a probability index (e.g. i; e.g. representing the current probability value) and a first size value (e.g. µ; wherein the size value, for example, describes an extension of the probability table) determines which element of the probability table is scaled in the first scaling; and / or an integer division result (⌊i / µ⌋) of a division between the probability index (i) and the first size value determines a scaling factor (2-⌊ i / µ ⌋) used in the second scaling; and / or the coding interval size determines a multiplicative scaling factor (Qr2(R)) of the first scaling. Using such a concept, a small probability table, which only represents an interval size in a (comparatively small) part of a two dimensional grid of probability indices and coding interval size indices, can be used, which saves memory space. An appropriate interval size information can then be obtained by the above-mentioned selection of an element of the probability table and also by the above-mentioned two-times scaling of the selected element of the probability table. In a preferred embodiment, the arithmetic encoder is configured to obtain an element ^^^^^^^^^^^^^^^^^^^^^^[^^][^^]of the two-dimensional lookup-table according to ^^^^^^^^^^^^^^^^^^^^^^[^^][^^] = ^^^^^^^^(⌊^^^^^^^^^^^^^^^^^^^^[^^ % ^^] ∙ ^^^^2(^^)⌋, ⌊^^ / ^^⌋)wherein i is a table index associated with a probability information; wherein j is a table index associated with an interval size information; wherein % is a division residual operation; wherein / is a division operation; wherein probTabLPS[] is the probability table; wherein µ is a number of elements of the probability table (wherein a range of values of I is typically larger than µ); wherein R is an interval size (or a current coding interval size); wherein Qr2(R) is a scaling factor which is dependent on R; wherein Scal (x,y) is a scaling function (for example, defined as Scal (x,y)= ⌊x*a-by⌋, wherein ⌊. ⌋ is a floor operation, wherein a is FH240412PEP-2025112831.DOCX preferably a constant larger than or equal to 2, and wherein b is preferably a constant larger than or equal to 1, and wherein the scaling function is preferably implemented using a shift- to-the -right bit shift operation, wherein y determines whether and by how many bits a shift- to-the-right of x is performed). By using such a concept for obtaining an appropriate element of the two dimensional lookup table, which may represent the interval size information or which may be equal to the interval size information, a very good tradeoff between memory requirements and computational complexity can be obtained. The table “probTabLPS” may, for example, be a one- dimensional table, wherein a number of elements of said table may be smaller than a number of different possible values of the table index ^^. However, by scaling the product of the selected element of the probability table probTabLPS and of the scaling factor Qr2(R), which is dependent on the interval size R, a good accuracy can be reached and possible rounding errors can be kept reasonably small. Furthermore, since the scaling operates on integer values, which are obtained by a “floor” operator, an efficient scaling concept can be used which may be defined, for example, by an integer multiplication or an integer division or a bit shift operation. Thus, the computational load is really small. In a preferred embodiment, the arithmetic encoder is configured to obtain an element ^^^^^^^^^^^^^^^^^^^^^^[^^][^^] of the two-dimensional lookup-table according to ^^^^^^^^^^^^^^^^^^^^^^[^^][^^] = ^^^^^^^^(⌊^^^^^^^^^^^^^^^^^^^^[^^ % ^^] ∙ ^^^^2(^^)⌋, ⌊^^ / ^^⌋)wherein i is a table index associated with a probability information; wherein j is a table index associated with an interval size information; wherein % is a division residual operation; wherein / is a division operation; wherein probTabLPS[] is the probability table; wherein µ is a number of elements of the probability table (wherein a range of values of I is typically larger than µ); wherein R is an interval size (or a current coding interval size); wherein Qr2(R) is a scaling factor which is dependent on R; wherein Scal (x,y) is a scaling function (for example, defined as Scal (x,y)= ⌊x*a-by⌋, wherein ⌊. ⌋ is a floor operation, wherein a is preferably a constant larger than or equal to 2, and wherein b is preferably a constant larger than or equal to 1, and wherein the scaling function is preferably implemented using a shift- to-the -right bit shift operation, wherein y determines whether and by how many bits a shift- to-the-right of x is performed). FH240412PEP-2025112831.DOCX This approach for obtaining an interval size information is also particularly efficient, and has been found to bring along high-quality results for the interval size information (which is obtained as a result of the first scaling and the second scaling). In a preferred embodiment of the arithmetic encoder, wherein a division residual ( ⌊i%µ⌋ ) of a division between a probability index (e.g. i; e.g. representing the current probability value) and a first size value (e.g. µ; wherein the size value, for example, describes an extension of the probability table) determines which element of the probability table is scaled in the first scaling; and / or wherein an integer division result ( ⌊i / µ⌋) of a division between the probability index (i) and the first size value determines a scaling factor (2-⌊ i / µ ⌋) used in the first scaling; and / or wherein the coding interval size (R) determines a multiplicative scaling factor (Qr2(R)) of the second scaling. By selecting an element of the probability table (which may be a one-dimensional probability table) in dependence on the above-mentioned division residual, the fact that interval sizes are substantially similar, except for a scaling, in different ranges of the probability index can be exploited. Accordingly, the probability table only reflects values in a single range of probability indices, and interval size values for other ranges of the probability index are obtained using the first scaling. The second scaling adapts the values represented by the probability table, or the values obtained on the basis thereof using the first scaling, to a coding interval size, in order to thereby obtain an appropriate interval size information. Consequently, a good tradeoff between memory consumption, computational complexity and accuracy can be obtained, wherein, for example, the division residual and the integer division result may be obtained in a computationally very simple manner if the first size value is chosen appropriately (for example, to be a potency of two). In a preferred embodiment, the arithmetic encoder is configured to obtain an element ^^^^^^^^^^^^^^^^^^^^^^[^^][^^]of the two-dimensional lookup-table according to ^^^^^^^^^^^^^^^^^^^^^^[^^][^^] = ⌊^^^^^^^^(^^^^^^^^^^^^^^^^^^^^[^^ % ^^], ⌊^^ / ^^⌋) ∙ ^^^^2(^^)⌋wherein i is a table index associated with a probability information; wherein j is a table index associated with an interval size information; wherein % is a division residual operation; wherein / is a division operation (e.g. providing an integer result); wherein probTabLPS[] is the probability table; wherein µ is a number of elements of the probability table (wherein a FH240412PEP-2025112831.DOCX range of values of I is typically larger than µ); wherein R is an interval size; wherein Qr2(R) is a scaling factor which is dependent on R; wherein Scal (x,y) is a scaling function (for example, defined as Scal (x,y)= ⌊x*a-by⌋, wherein ⌊. ⌋ is a floor operation, wherein a is preferably a constant larger than or equal to 2, and wherein b is preferably a constant larger than or equal to 1, and wherein the scaling function is preferably implemented using a shift- to-the -right bit shift operation, wherein y determines whether and by how many bits a shift- to-the-right of x is performed). This computational rule implements the before-mentioned concepts in a very efficient manner. In a preferred embodiment of the arithmetic encoder, the two-dimensional look-up table is representable as a dyadic product between a first one-dimensional vector (forming a one- dimensional look-up table) entries of which comprise probability values for different value intervals of a value domain for the first and second state variable values, or the scaledand / or rounded version ( ⌊sk* ak ⌋; ⌊|^^^^| ∙ ^^^^⌋) thereof, and a second one-dimensional vector(^^^^2(^^)) entries of which comprise quantization levels for the coding interval size information. Such a two-dimensional lookup table is well-usable for an efficient derivation of the interval size information on the basis of the state variable values and on the basis of a coding interval size information. A lookup within the two dimensional lookup table corresponds to a mapping of a state variable value onto a probability value and also to a multiplication of the obtained probability value with a coding interval size. Thus, it is very easily possible to obtain the interval size information, which may be equal to the selected entry of the two dimensional lookup table, wherein a respective element of the two dimensional lookup table may be selected in dependence on the respective state variable value and independence on the coding interval size information (wherein the respective state variable value may determine a first index of the element of the two dimensional lookup table, and wherein the coding interval size information may determine the second index). In a preferred embodiment, the arithmetic encoder is configured to compute from the first and second state variable values, or the scaled and / or rounded version ( ⌊sk* ak⌋ ) thereof, first and second subinterval width values (R*pk), respectively, by mapping the first and second state variable values (sk), or a scaled and / or rounded version thereof ( ⌊sk2* ak2⌋ ) using a one-dimensional look-up table (LUT4) entries of which comprise probability values FH240412PEP-2025112831.DOCX for different value intervals of a value domain for the first and second state variable values, or the scaled and / or rounded version ( ⌊sk* ak⌋ ) thereof, onto a first and second probability value, and quantizing a coding interval size information (e.g. R) describing a size of a coding interval of the arithmetic encoding before an encoding of a symbol onto a quantization level; determine products (either by look-up of precomputed products, or by multiplication) between the first and second probability value, on the one hand, and the quantization level, and obtaining a combined subinterval width value using the first subinterval width value and the second subinterval width value (for example, using a weighted summation or using a weighted averaging). It has been found that using such an approach is also very efficient under certain circumstances. By deriving a first subinterval width value on the basis of the first state value only (but without considering the second state value) and by computing a second subinterval width value on the basis of the second state variable value only (but without considering the first state variable value), a substantially separate handling of the state variable values, which are obtained using different adaptation time constants, is maintained through most of the processing. Only in a final stage, the first subinterval width a value and the second subinterval width value are combined, to obtain a combined subinterval width value which brings along a high precision and avoids degradations which would, under some circumstances, occur if the first state variable value and the second state variable value were combined at a too-early stage. In a preferred embodiment, the arithmetic encoder is configured to perform the quantizing the coding interval size information by applying a logical right shift onto the coding interval size information. This concept is particularly easy to implement, since a logical right shift requires only minimal computational resources. In a preferred embodiment, the arithmetic encoder is configured to perform the quantizingthe coding interval size information ^^ by ^^^^2(^^) = (⌊^^ ∙ 2−^^⌋ + ^^) ∙ 2−^^, where ^^, ^^ and ^^are parameters. It has been found that such a quantization can also be implemented very easily. Inparticular, the computational effort is very low if the parameters ^^, ^^ and ^^ are chosen to beinteger values (or integer values larger than 1). FH240412PEP-2025112831.DOCX In a preferred embodiment of the arithmetic encoder, the entries of the one-dimensional look-up table monotonically decrease at an increase of the first and second state variable values, or the scaled and / or rounded version ( ⌊sk* ak⌋ ) thereof. Using monotonically decreasing entries of the one dimensional lookup table has shown to bring along good results for the interval size information. In a preferred embodiment of the arithmetic encoder, wherein different value intervals of the value domain for the first and second state variable value, or the scaled and / or rounded version ( ⌊sk* ak⌋ ) thereof, are equally sized. Using such an equal sizing of the value intervals allows for a simple quantization. Furthermore, an equal sizing of the value intervals allows for an on-the-fly determination of elements of the look-up table with moderate effort. In a preferred embodiment of the arithmetic encoder, wherein different value intervals of the value domain for the first and second state variable value, or the scaled and / or rounded version ( ⌊sk* ak⌋ ) thereof, are equally sized. Using such a monotonic decrease of the entries of the one dimensional lookup table, it is possible to represent an exponential decay with good accuracy. An embodiment according to the invention creates an arithmetic encoder for encoding a plurality of symbols having symbol values (e.g. binary values), wherein the arithmetic encoder is configured to derive an interval size information (pk, R*pk) for an arithmetic encoding of one or more symbol values to be encoded on the basis of a plurality of state variable values (sik) (which are, for example, associated with a given context mode, indicated by index k), which represent statistics of a plurality of previously encoded symbol values (e.g. a sequence of binary values 0 and 1) with different adaptation time constants, wherein the arithmetic encoder is configured to derive a combined state variable value (sk) (which may, for example, be a weighted sum of state variable values) one the basis of the plurality of (individual) state variable values (sik), and wherein the arithmetic encoder is configured to map the combined state variable value (sk), or a scaled and / or rounded version thereof ( ⌊sk2* ak2⌋ ) using a look-up table, in order to obtain the interval size FH240412PEP-2025112831.DOCX information (e.g. pkor R*pk) describing an interval size for the arithmetic encoding of one or more symbols to be encoded. This embodiment according to the invention is based on the idea that a high efficiency in the determination of the interval size information is obtained if a combined state variable value is determined before a mapping is performed using a lookup table. Accordingly, it is no longer necessary to perform separate lookup-table lookups using the two (or more) state variable values. Rather, a single table lookup may be sufficient in order to determine the interval size information. In particular, it has been found that the combination of the first state variable value and of the second state variable value before performing the lookup- table lookup does not severely degrade the quality of the interval size information under many circumstances. In a preferred embodiment, the arithmetic encoder is configured to determine a weighted sum of state variable values, in order to obtain the combined state variable value. It has been found that the computation of a weighted sum of the state variable values is an efficient manner to determine the combined state variable value and is also well-suited to consider the different relevance of the two state variable values, which is caused by the different adaptation time constants used when deriving the state variable values. In a preferred embodiment, the arithmetic encoder is configured to determine a sum of rounded values ( ∙ ^^^^^^⌋), which are obtained by rounding products of state variable values (^^^^^^) and associated weight values (^^^^^^), in order to obtain the combined state variable value (sk). It has been found that performing a rounding of scaled values before performing a summation brings along a particularly meaningful result. Negligible contributions of one of the state variable values are eliminated by the rounding and do not affect the combined state variable value. Accordingly, highly reliable results can be obtained, and a combined state variable value typically takes an integer value, which is well-suited to serve as an index for selecting an element of a lookup table. In a preferred embodiment, the arithmetic encoder is configured to determine the combined state variable value sk according to FH240412PEP-2025112831.DOCX wherein sk2 are state variable values, wherein N is a number of state variable values considered, wherein ⌊ . ⌋ is a floor operator, wherein dki are weighting values associated with the state variable values (for example, weighting factors that control the influence of the individual state variable values onto the combined state variable value) (wherein dki are preferably integer-valued potencies of von 2, and wherein a ratio between two different dki is preferably an integer-valued potency of 2)[wherein a ratio between two different dkiis preferably larger than or equal to 8). This concept for the derivation of the combined state variable value brings along very meaningful combined state variable values, as explained before. In a preferred embodiment, the arithmetic encoder is configured to change the state variable value into a first direction (e.g. to become more positive) if a symbol to be encoded takes a first value (e.g. “1”), and to change the state variable value into a second direction (e.g. to become more negative) if a symbol to be encoded takes a second value (e.g. “0”) which is different from the first value (for example, such that the state variable value can take positive and negative values), and wherein the arithmetic encoder is configured to determine an entry of the lookup-table to be evaluated in dependence on an absolute value (sk if ski>0, - sk otherwise) of the combined state variable value (e.g in dependence on a scaled and rounded version of an absolute value of the combined state variable value). This concept for the determination of the state variable values (e.g., for the determination of the first state variable value and for the second state variable value) brings along the same advantages as in the case where a separate mapping of the first state variable value and of the second state variable value is used. In a preferred embodiment, the arithmetic encoder is configured to set a probability value(pk) to a value provided by the lookup table (e.g. to ^^^^^^2[⌊ ^^^^ ∙ ^^^^ ⌋] ) if the combined statevariable value takes a first sign (e.g. a positive sign), and wherein the arithmetic encoder is configured to set the probability value (pk) to a value obtained by subtracting a value FH240412PEP-2025112831.DOCXprovided by the lookup table (e.g. to ^^^^^^2[⌊− ^^^^ ∙ ^^^^ ⌋] ) from a predetermined value (e.g.1) if the combined state variable value takes a second sign (e.g. a negative sign). This concept for mapping the combined state variable value onto a probability value is efficient, since the size of the lookup table can be reduced. In particular, a number of elements of the lookup table can be reduced, since a same element of the lookup table is associated with a given positive combined state variable value and a negative version of the given (positive) combined state variable value. In other words, in the given concept, the absolute value of the combined state variable value determines which element of the lookup table is evaluated for the provision of the probability value. However, the sign of the combined state variable value is still considered in an appropriate and efficient manner by setting the probability value to the value provided by the lookup table or to a value obtained by subtracting a value provided by the lookup table from a predetermined value dependent on the sign. Accordingly, a meaningful probability value can be obtained on the basis of the combined state value with low computational complexity. In a preferred embodiment, the arithmetic encoder is configured to determine a combined probability value pk according to wherein LUT2 is a lookup-table containing probability values; wherein ⌊ . ⌋ is a floor operator; wherein skis a combined variable value; and wherein akis a weighting value associated with the combined state variable value (for example, a weighting value that adapts a number range of the i-th state variable value to a number of entries of the lookup-table). This concept for the determination of the combined probability value on the basis of the combined state variable value sk implements the idea outlined before in a computationally highly efficient manner. In a preferred embodiment, the arithmetic encoder is configured to determine a combined probability value pk according to FH240412PEP-2025112831.DOCX wherein LUT2 is a lookup-table containing probability values; wherein ⌊ . ⌋ is a floor operator; wherein skis a combined variable value; and wherein akis a weighting value associated with the combined state variable value (for example, a weighting value that adapts a number range of the i-th state variable value to a number of entries of the lookup-table). In this concept, there is no absolute value computation of the scaled combined state variable value sk. Rather, there is only a “floor” operation, which is applied to the scaled (“weighted”) combined state variable value which can, in some circumstance, be implemented with lower effort than an absolute value formation. A negation is only applied to an integer value, which is obtained by a downward-rounding (floor operator) of the weighted combined state variable value. However, negating an integer value is typically less complicated than negating a fractional value or a value in a floating point representation. Accordingly, the concept discussed here can be helpful to reduce a complexity under some circumstances. In a preferred embodiment, the arithmetic encoder is configured to map the combined state variable value, or the scaled and / or rounded version ( ⌊sk* ak⌋ ) thereof, onto a subinterval width value (R*pk) using a two-dimensional look-up table, entries of which are addressed in dependence on the combined state variable value (e.g. to determine a first lookup table entry coordinate) and in dependence on a coding interval size information (e.g. R) describing a size of a coding interval of the arithmetic encoding before an encoding of a symbol (e.g. to determine a second lookup table entry coordinate). Using this concept, a mapping of the combined state variable value onto a combined probability value and a multiplication of the combined probability value with a coding interval size can be combined into a single lookup table lookup operation. Accordingly, a two dimensional lookup table is needed, but a multiplication operation is saved. The entries of the two dimensional lookup table may be pre-computed, which keeps the combinational load at run time very low. Rather, a first table index may be determined on the basis of a combined state variable value, or a scaled and / or rounded version thereof, and a second table index may be determined on the basis of a coding interval size information (for example, using a rounding or a quantization). The first step index and the second state index may uniquely designate an element of the two dimensional lookup table, and the designated element of the two dimensional lookup table may be used as the sub interval FH240412PEP-2025112831.DOCX width value (or as the interval size information). Accordingly, a very efficient concept is obtained, which saves computational complexity in case that sufficient memory for the lookup table is available. In a preferred embodiment of the arithmetic encoder, the two-dimensional look-up table isrepresentable as a dyadic product between a first one-dimensional vector (^^^^^^4[… ];forming a one-dimensional look-up table) entries of which comprise probability values for different value intervals of a value domain for the combined state variable value, or thescaled and / or rounded version ( ⌊sk* ak ⌋; |^^^^| ∙ ^^^^) thereof, and a second one-dimensionalvector (^^^^2(^^)) entries of which comprise quantization levels for the coding interval size information. Such a two dimensional lookup table brings along very good results. In particular, all the elements of this two dimensional lookup table represent the multiplication of respective probability values associated with the combined state variable values and of a coding interval size. Thus, the two dimensional lookup table described herein eliminates the need for a multiplication, which can be considered as very resource efficient. In a preferred embodiment of the arithmetic encoder, elements of the two-dimensional lookup-table (RangTabLPS) are defined on the basis of a base lookup table (Base TabLPS), wherein a first group (or block; e.g. an “upper half”) of the elements of the two-dimensional lookup-table are identical to elements of the base lookup-table or are rounded versions of elements of the base lookup table, and wherein a second group, (or block; e.g. a “lower half”) of the elements of the two-dimensional lookup-table are scaled and rounded versions of elements of the base lookup-table. By defining the element of the two dimensional lookup table on the basis of a base lookup table, the two dimensional lookup table can be generated in a very simple manner. Furthermore, since the second group of elements of the two dimensional lookup table are scaled and rounded versions of the elements of the base lookup table (while the elements of the first group of elements of the two dimensional lookup table are identical to elements of the base lookup table or are rounded versions of elements of the base lookup table) an exponential evolution of the elements in a row or in a column of the two dimensional lookup table is well reflected. By using the concept that a second block of the elements of the two dimensional lookup table is substantially (except for rounding effects) a scaled version of a first block of elements of the two dimensional lookup table, it is possible to reflect an FH240412PEP-2025112831.DOCX appropriate characteristic for mapping the combined state variable value onto an interval size information. In a preferred embodiment of the arithmetic encoder, the second group of elements of the two-dimensional lookup-table are right-shifted versions of elements of the base-lookup table. This allows for a simple generation of the entries (elements) of the two-dimensional lookup- table. It has been found that a right-shifting element of the base-lookup table is a very efficient concept which combines a scaling and a rounding operation. In a preferred embodiment of the arithmetic encoder, a probability index (Qp2(pLPS) or i) determines whether an element of the first group of elements of the two-dimensional lookup table or an element of a second group of elements of the two-dimensional lookup table is evaluated, wherein a first range (for example, between 0 and µ-1) of probability indices (which are, for example, obtained by quantizing a probability value, e.g. pLPS) is associated with elements of the first group of elements, and wherein a second range (for example, larger than or equal to µ) of probability indices (which are, for example, obtained by quantizing a probability value, e.g. pLPS, e.g. using a quantization function Qp2(.)) is associated with elements of the second group of elements. By using a probability index, which may be derived directly from the combined state variable value (without using a probability value as an intermediate quantity) or which may be derived using a combined probability value which is based on a combined state variable value, a selection of an element of the two dimensional lookup table may be made very efficiently. Also, the probability index is used to switch between a usage of elements of the first group of elements and elements of the second group of elements, which allows for an efficient on- the-fly determination of elements of the two dimensional lookup table. In a preferred embodiment of the arithmetic encoder, a division residual (i%µ) of a division between the probability index (i) and a first size value (e.g. µ; wherein the size value, for example, describes an extension of the base lookup table in a first direction) and an interval size index (which may, for example, be obtained on the basis on an interval size information R, for example using a quantization operation Qr2(.); for example, j) determine which FH240412PEP-2025112831.DOCX element of the base lookup table is used to obtain the element of two-dimensional lookup table. In a preferred embodiment, the arithmetic encoder is configured to obtain an element of the two-dimensional lookup-table (RangTabLPS) according to RangeTabLPS[i][j]=Scal(BaseTabLPS[i%µ][j] , ⌊i / µ⌋) wherein BaseTabLPS is a base lookup table of dimension µ x λ; wherein i is a table index associated with a probability information; wherein j is a table index associated with an interval size information (e.g. describing a current coding interval size); wherein % is a division residual operation; wherein / is a division operation; wherein Scal (x,y) is a scaling function (for example, defined as Scal (x,y)= ⌊x*a-by⌋, wherein ⌊. ⌋ is a floor operation, wherein a is preferably a constant larger than or equal to 2, and wherein b is preferably a constant larger than or equal to 1, and wherein the scaling function is preferably implemented using a shift-to-the -right bit shift operation, wherein y determines whether and by how many bits a shift-to-the-right of x is performed). By evaluating said division residual to determine which element of the base lookup table is used to obtain the element of the two dimensional lookup table, an on-the-fly determination of the elements of the two dimensional lookup table can be performed with very high efficiency. In particular, the fact that the two dimensional lookup table comprises two or more groups of elements, which are based on the same elements of the base lookup table, can be reflected by the usage of the division residual for the determination which elements of the base lookup table is used to obtain the element of the two dimensional lookup table. In other words, a periodic relationship between elements of the two dimensional lookup table and elements of the base lookup table is well-reflected by the consideration of said division residual, since the division residual is also periodic with increasing probability index. In a preferred embodiment of the arithmetic encoder, elements of the two-dimensional lookup-table (RangTabLPS) are defined on the basis of a probability table (probTabLPS), wherein the probability table describes interval sizes for a set of a plurality of probability values (for example, represented by indices i) and for a given (reference) coding interval size, and wherein elements of the two-dimensional lookup-table for a probability value which is not in the set of a plurality of probability values and / or for a coding interval size which is FH240412PEP-2025112831.DOCX different from the given coding interval size are derived from the probability table using a scaling. This concept is based on the same considerations like the corresponding concept described for the case of a separate mapping of the state variable values. In a preferred embodiment of the arithmetic encoder, elements of the two-dimensional lookup-table (RangTabLPS) are defined on the basis of a probability table (probTabLPS), wherein the probability table describes interval sizes for a set of a plurality of probability values (for example, represented by indices i) and for a given (reference) coding interval size, and wherein elements of the two-dimensional lookup-table for a probability value which is not in the set of a plurality of probability values and / or for a coding interval size which is different from the given coding interval size are derived from the probability table using a scaling. It has been found that such an on-the-fly determination of an element of the two dimensional lookup table comprises a particularly high resource efficiency. Furthermore, it should be noted that the above comments made with respect to the corresponding algorithm used within the context of a separate mapping of the first state variable value and of the second state variable value also apply. By using a probability table, which is typically smaller (e.g., comprises less elements) than the two dimensional lookup table, as the basis for a determination of the elements of the two dimensional lookup table, a very high efficiency can be obtained. For example, the probability table may represent the mapping of different probability values and the different (quantized) coding interval sizes over a significant range, and may therefore help to avoid multiplications which go beyond a simple scaling (wherein a “simple” scaling may, for example, be implemented using shift operations). Elements of the two dimensional lookup table for one or more probability values which are not in the set of a plurality of probability values and for one or more coding interval sizes which are different from the given coding interval size are derived from the probability table using a scaling. Accordingly, it is sufficient to have a very small probability table, which may, for example, only comprise one row or one column. So, the number of elements of the probability table may even be smaller than the number of different possible probability values (i.e., smaller than the number of different possible probability indexes of the two dimensional lookup table). Furthermore, it should be noted that the scaling depends on the probability values and / or depends on the coding interval size. The scaling may, for example, FH240412PEP-2025112831.DOCX be performed using a very simple mechanism, like a bit-shift operation if the size of the probability table is chosen appropriately. Such “simple” scaling operations, which are based on bit-shift operations, require significantly less computational resources when compared to “normal” multiplications with arbitrary variable operands (which are, for example, different from potencies of two). In a preferred embodiment of the arithmetic encoder, elements of the two-dimensional lookup-table are obtained using a (multiplicative) first scaling of a selected element (probTabLPS[i%µ]) of the probability table in dependence on the coding interval size (R), and using a second scaling of a result of the first scaling in dependence on whether an element associated with a current probability value (designated by index i) is included in the set of probability values or not (e.g. in dependence on whether the current probability value lies within a range of probability values covered by the probability table or not). It has been found that such a computation of elements of the two dimensional lookup table is particularly efficient. Furthermore, reference is also made to the above discussion of the corresponding functionality provided in the context of a separate mapping of the first state variable value and of the second state variable value. In a preferred embodiment of the arithmetic encoder, a division residual (i%µ) of a division between a probability index (e.g. i; e.g. representing the current probability value) and a first size value (e.g. µ; wherein the size value, for example, describes an extension of the probability table) determines which element of the probability table is scaled in the first scaling; and / or wherein an integer division result (⌊i / µ⌋) of a division between the probability index (i) and the first size value determines a scaling factor (2-⌊ i / µ ⌋) used in the second scaling; and / or wherein the coding interval size determines a multiplicative scaling factor (Qr2(R)) of the first scaling. Regarding this functionality, reference is also made to the above discussion of the corresponding functionality provided in the context of a separate mapping of the first state variable value and of the second state variable value. In a preferred embodiment, the arithmetic encoder is configured to obtain an element ^^^^^^^^^^^^^^^^^^^^^^[^^][^^] of the two-dimensional lookup-table according to FH240412PEP-2025112831.DOCX^^^^^^^^^^^^^^^^^^^^^^[^^][^^] = ^^^^^^^^(⌊^^^^^^^^^^^^^^^^^^^^[^^ % ^^] ∙ ^^^^2(^^)⌋, ⌊^^ / ^^⌋)wherein i is a table index associated with a probability information; wherein j is a table index associated with an interval size information; wherein % is a division residual operation; wherein / is a division operation; wherein probTabLPS[] is the probability table; wherein µ is a number of elements of the probability table (wherein a range of values of I is typically larger than µ); wherein R is an interval size (or a current coding interval size);wherein Qr2(R) is a scaling factor which is dependent on R; wherein Scal (x,y) is a scaling function (for example, defined as Scal (x,y)= ⌊x*a-by⌋, wherein ⌊. ⌋ is a floor operation, wherein a is preferably a constant larger than or equal to 2, and wherein b is preferably a constant larger than or equal to 1, and wherein the scaling function is preferably implemented using a shift- to-the -right bit shift operation, wherein y determines whether and by how many bits a shift- to-the-right of x is performed). Regarding this functionality, reference is also made to the above discussion of the corresponding functionality provided in the context of a separate mapping of the first state variable value and of the second state variable value. In a preferred embodiment of the arithmetic encoder, elements of the two-dimensional lookup-table are obtained using a (multiplicative) first scaling of a selected element (probTabLPS[i%µ]) of the probability table in dependence on whether an element associated with a current probability value (designated by index i) is included in the set of probability values or not (e.g. in dependence on whether the current probability value lies within a range of probability values covered by the probability table or not) and using a second scaling of a result of the first scaling in dependence on the coding interval size (R). Regarding this functionality, reference is also made to the above discussion of the corresponding functionality provided in the context of a separate mapping of the first state variable value and of the second state variable value. In a preferred embodiment of the arithmetic encoder, a division residual ( ⌊i%µ⌋ ) of a division between a probability index (e.g. i; e.g. representing the current probability value) and a first size value (e.g. µ; wherein the size value, for example, describes an extension of the probability table) determines which element of the probability table is scaled in the first scaling; and / or wherein an integer division result (⌊i / µ⌋) of a division between the probability FH240412PEP-2025112831.DOCX index (i) and the first size value determines a scaling factor (2-⌊ i / µ ⌋) used in the first scaling; and / or wherein the coding interval size (R) determines a multiplicative scaling factor (Qr2(R)) of the second scaling. Regarding this functionality, reference is also made to the above discussion of the corresponding functionality provided in the context of a separate mapping of the first state variable value and of the second state variable value, wherein the combined state variable value or the combined probability value is used instead of the respective individual state variable value or the respective individual probability values. In a preferred embodiment, the arithmetic encoder is configured to obtain an element ^^^^^^^^^^^^^^^^^^^^^^[^^][^^] of the two-dimensional lookup-table according to ^^^^^^^^^^^^^^^^^^^^^^[^^][^^] = ⌊^^^^^^^^(^^^^^^^^^^^^^^^^^^^^[^^ % ^^], ⌊^^ / ^^⌋) ∙ ^^^^2(^^)⌋wherein i is a table index associated with a probability information; wherein j is a table index associated with an interval size information; wherein % is a division residual operation; wherein / is a division operation (e.g. providing an integer result); wherein probTabLPS[] is the probability table; wherein µ is a number of elements of the probability table (wherein a range of values of I is typically larger than µ); wherein R is an interval size; wherein Qr2(R) is a scaling factor which is dependent on R; wherein Scal (x,y) is a scaling function (for example, defined as Scal (x,y)= ⌊x*a-by⌋, wherein ⌊. ⌋ is a floor operation, wherein a is preferably a constant larger than or equal to 2, and wherein b is preferably a constant larger than or equal to 1, and wherein the scaling function is preferably implemented using a shift- to-the -right bit shift operation, wherein y determines whether and by how many bits a shift- to-the-right of x is performed). Regarding this functionality, reference is also made to the above discussion of the corresponding functionality provided in the context of a separate mapping of the first state variable value and of the second state variable value, wherein the combined state variable value takes the place of the individual state variable values and wherein the combined probability value takes the place of the individual probability values. In a preferred embodiment, the arithmetic encoder is configured to compute from the combined state variable value, or the scaled and / or rounded version ( ⌊sk* ak⌋ ) thereof, a subinterval width value (R*pk) by mapping the combined state variable value (sk), or a scaled FH240412PEP-2025112831.DOCXand / or rounded version thereof ( ⌊sk* ak ⌋; ⌊|^^^^| ∙ ^^^^⌋) using a one-dimensional look-up table(LUT4) entries of which comprise probability values for different value intervals of a value domain for the combined state variable value, or the scaled and / or rounded version ( ⌊sk* ak⌋; ⌊|^^^^| ∙ ^^^^⌋) thereof, onto a combined probability value, and quantizing a coding intervalsize information (e.g. R) describing a size of a coding interval of the arithmetic encoding before an encoding of a symbol onto a quantization level; a product (either by look-up of precomputed products, or by multiplication) between the combined probability value and the quantization level. Regarding this functionality, reference is also made to the above discussion of the corresponding functionality provided in the context of a separate mapping of the first state variable value and of the second state variable value, wherein the combined state variable value takes the place of the individual state variable values, and wherein the combined probability value takes the place of the individual probability values. In a preferred embodiment, the arithmetic encoder is configured to perform the quantizing the coding interval size information by applying a logical right shift onto the coding interval size information. Regarding this functionality, reference is also made to the above discussion of the corresponding functionality provided in the context of a separate mapping of the first state variable value and of the second state variable value. In a preferred embodiment, the arithmetic encoder is configured to perform the quantizingthe coding interval size information ^^ by ^^^^2(^^) = (⌊^^ ∙ 2−^^⌋ + ^^) ∙ 2−^^, where ^^, ^^ and ^^are parameters. Regarding this functionality, reference is also made to the above discussion of the corresponding functionality provided in the context of a separate mapping of the first state variable value and of the second state variable value. In a preferred embodiment of the arithmetic encoder, the entries of the one-dimensional look-up table monotonically decrease at an increase of the combined state variable value, or the scaled and / or rounded version ( ⌊sk* ak⌋ ) thereof. FH240412PEP-2025112831.DOCX Regarding this functionality, reference is also made to the above discussion of the corresponding functionality provided in the context of a separate mapping of the first state variable value and of the second state variable value. In a preferred embodiment of the arithmetic encoder, different value intervals of the value domain for the combined state variable value, or the scaled and / or rounded version ( ⌊sk* ak⌋ ) thereof, are equally sized. Regarding this functionality, reference is also made to the above discussion of the corresponding functionality provided in the context of a separate mapping of the first state variable value and of the second state variable value. In a preferred embodiment of the arithmetic encoder, the entries of the one-dimensional look-up table monotonically decrease with decreasing rate at an increase of the combined state variable value, or the scaled and / or rounded version ( ⌊sk* ak⌋ ) thereof. Regarding this functionality, reference is also made to the above discussion of the corresponding functionality provided in the context of a separate mapping of the first state variable value and of the second state variable value. In a preferred embodiment of the arithmetic encoder, the lookup-table defines (for example, within a tolerance of + / -10% or + / -20%) an exponential decay (e.g. down from 0.5). It has been found that an exponential decay well reflects an appropriate relationship for a derivation of an interval size information on the basis of state variable values. Also, an exponential decay can be represented very efficiently using a lookup table, wherein even an on-the-fly determination of elements of the lookup table is possible with small effort. In a preferred embodiment, the arithmetic encoder is configured to update the plurality of variable state values ^^^^^^according to wherein z is a predetermined (constant) offset value; wherein are one or more weighting values; wherein ^^^^^^ are one or more weighting values, wherein A is ^^[^^ + ^̂^] = ^^^^^^^^^^^^ +FH240412PEP-2025112831.DOCX or deviates therefrom merely for one or more extreme values of its argument by zero setting or magnitude reduction to avoid the updated ^^^^^^leaving a predetermined value range, (e.g. consider that ^^^^^^has a value domain larger than ^^^^^^∙ ^^^^^^; that is, ^^^^^^is quasi quantized onto ^^^^^^ ∙ for extreme values of ^^^^^^ ∙ ^^^^^^, ^^^^^^may be modified by an unamended A according to above formula to leave its value domain; to avoid this, the entries corresponding to these extreme values might be reduced or zeroed), where ^^^^^^^^^^^^, ^̂^, ^̂^^^, and ^̂^^^are predetermined parameters (examples are set out above). It has been found that such an update of the state variables can be done with high computational efficiency, wherein the mapping table may be precomputed. For example, it can be achieved that the state variable values ^^^^^^remain with a predetermined range (for example, between a predetermined minimum value and a predetermined maximum value). Moreover, using an appropriate choice of the mapping table A, it can be achieved that the state variable values are well adapted for a description of statistics of previously processed (e.g., encoded or decoded) symbols. Also, it should be noted that an adaptation time constant of the respective state variable values can be adapted by an appropriate choice of the weighting values m and n. Thus, the algorithm described here can be efficiently used for the update of the state variable values ^^^^^^.In a preferred embodiment, the arithmetic encoder is configured to derive ^^[^^ + by table look-up or computationally. Thus, different concepts are possible to derive the updated state variable values. An embodiment according to the invention creates an arithmetic encoder for encoding a plurality of symbols having symbol values (e.g. binary values), wherein the arithmetic encoder is configured to determine one or more state variable values (s1k, s2k), which represent statistics of a plurality of previously encoded symbol values (e.g. a sequence of binary values 0 and 1) (for example, in the case of a plurality of state variable values, statistics with different adaptation time constants), and wherein the arithmetic encoder is configured to derive an interval size information (pk, R*pk) for an arithmetic encoding of one or more symbol values to be encoded on the basis of the one or more state variable values (sik) (which are, for example, associated with a given context mode, indicated by index k), which represent statistics of a plurality of previously encoded symbol values (e.g. a sequence of binary values 0 and 1) (for example, in the case of a plurality of state variable FH240412PEP-2025112831.DOCX values, statistics with different adaptation time constants), wherein the arithmetic encoder is configured to update a first state variable value (sk1) in dependence on a symbol to be encoded and using a look-up table (A) (for example, after encoding the symbol to be encoded). This embodiment according to the invention is based on the finding that an update of a state variable value, which is used for a derivation of an interval size information for an arithmetic coding (e.g., an encoding or a decoding) can be performed with particularly good results using a lookup table, because the usage of a lookup table allows for an update of the state variable value which is particularly well-adapted to characteristics of a signal to be encoded or to be decoded. For example, it is easily possible to represent a fine-tuned relationship between an “old” state variable value and an updated state variable value using a lookup table, while there is no need to perform extensive computations (like, for example, an evaluation of a trigonometric function or of an exponential function or of a logarithmic function, or the like). Thus, an implementation of an update of a state variable value using a lookup table helps to keep a computational complexity reasonably small. Ideally, only multiplications (or simple multiplications, e.g. bit shift operations), rounding operations and additions are used beside the lookup table lookup in order to obtain the updated state variable value on the basis of the “old” state variable value. For example, the currently processed symbol (for example, a symbol to be encoded or a decoded symbol) decides which part of a, for example, lookup-table based mapping rules is evaluated in order to obtain the updated state variable value. To conclude, the provision of an updated state variable value using a lookup table has been found to provide both a high flexibility and a low computational complexity. In a preferred embodiment, the arithmetic encoder is configured to update a second state variable value (sk2) in dependence on a symbol to be encoded and using the look-up table (A) (for example, after encoding the symbol to be encoded). It has been found that it is advantageous to update a second state variable value using the same lookup table which is used to update the first state variable value. Possible differences, for example, with respect to the adaptation time constants of the first state variable value and the second state variable value, can be considered, for example, using one or more scaling factors, which may, for example, be applied in the selection of an element of the lookup table and / or for a scaling of a selected element of the lookup table. FH240412PEP-2025112831.DOCX To conclude, even if only a single lookup table is used for the derivation of two or more state variable values, the two or more state variable values can be adapted to represent different statistic characteristics of the handled symbol values (i.e., of the previously encoded symbol values or of the decoded symbol values). In a preferred embodiment, the arithmetic encoder is configured update the first state variable value and the second state variable values using different adaptation time constants. By updating the first state variable value and the second state variable value using different adaptation time constants, different statistic characteristics of the previously handled symbols can be reflected by the state variable values. It has been found that the availability of state variable values representing statistics of the handled symbols with different adaptation time constants is very helpful for an accurate adjustment of an interval size for the arithmetic coding (encoding / decoding) of the symbols. Also, it has been found that lookup-table-based update of the state variable values provides a very high reliability and a low computational complexity. In a preferred embodiment, the arithmetic encoder is configured to selectively increase or decrease a previous state variable value by a value determined using the look-up table in dependence on whether a symbol to be encoded takes a first value or a second value which is different from the first value. By using such an approach, the state variable value can be adapted recursively, wherein the handled symbol (for example, a symbol to be encoded, or a previously encoded symbol, or a previously decoded symbol) determines the direction (increase or decrease) of the change of the state variable value. On the other hand, the size of the adaptation (i.e., of the increase or decrease) is determined by the selected lookup table entry, wherein a scaling may apply. Consequently, there is an efficient mechanism for the update of the state variable value, which provides a high degree of flexibility and still is very resource-efficient. In a preferred embodiment, the arithmetic encoder is configured to increase a previous state variable value by a comparatively larger value in case that the previous state variable value is negative when compared to a case that the previous state variable value is positive if a symbol to be encoded takes a first value; and wherein the arithmetic encoder is configured to decrease a previous state variable value by a comparatively larger value in case that the FH240412PEP-2025112831.DOCX previous state variable value is positive when compared to a case that the previous state variable value is negative if a symbol to be encoded takes a second value which is different from the first value (which is reached, for example, by an appropriate choice of the lookup- table). Using such an approach, it can be reached that a state variable value develops towards a maximum positive value in an exponential manner, and develops towards a minimum value in an exponential manner. This approximation towards the (positive) maximum value and towards the (negative) minimum value may be in an approximately asymptotic manner. In other words, the further the current state variable value is away from the (positive) maximum value, the larger the (increase) step towards the (positive) maximum value, and the further the current state variable value is away from the (negative) minimum value, the larger the (decrease) step towards the (negative) minimum value. Thus, an exponential asymptotic behavior can be approximated using this concept. However, it has been found that such a concept is very well-suited for the update of the state variable values. In particular, it has been found that such an approach is well suited for an “infinite impulse response” approach for the determination of the state variable value. In a preferred embodiment, the arithmetic encoder is configured to determine an index of an entry of the lookup table to be evaluated when updating the first state variable value in dependence on a sum of a predetermined (e.g. fixed) offset value (z) and a previously computed first state variable value ( ^^1^^), or a scaled and / or rounded version ( ⌊ ) thereof, if a symbol to be encoded takes a first value; and wherein the arithmetic encoder is configured to determine an index of an entry of the lookup table to be evaluated when updating the first state variable value in dependence on a sum of a predetermined (e.g. fixed) offset value (z) and a in inversed (multiplied by -1) version ( −^^1^^) of a previously computed first state variable value, or a scaled and / or rounded version ( thereof (e.g. of the inversed version of the previously computed first state variable value), if a symbol to be encoded takes a second value. Using such approach, an appropriate entry of the lookup table can be selected with moderate effort, taking into consideration a currently handled symbol. Both the previously computed state variable value and the handled (encoded or decoded) symbol determine the selection of an entry of the lookup table, and may consequently determine by how much the updated state variable value is increased or decreased when compared to the previously computed state variable value. The offset value may, for example, ensure that FH240412PEP-2025112831.DOCX the sum of the offset value and of the scaled (and possibly inversed, depending on the handled symbol) previously computed state variable value results in a valid lookup table index since valid lookup table indices are typically non-negative. Using such a concept, it is easily possible to select an appropriate lookup table index and to efficiently provide the updated state variable value. In a preferred embodiment, the arithmetic encoder is configured to determine an index of an entry of the lookup table to be evaluated when updating the second state variable value in dependence on a sum of a predetermined (e.g. fixed) offset value (z) and a previously computed second state variable value ( ^^2^^), or a scaled and / or rounded version ( ⌊ ^^^^2 ∙) thereof, if a symbol to be encoded takes a first value; and wherein the arithmetic encoder is configured to determine an index of an entry of the lookup table to be evaluated when updating the second state variable value in dependence on a sum of a predetermined (e.g. fixed) offset value (z) and a in inversed (multiplied by -1) version ( −^^2^^) of a previously computed second state variable value, or a scaled and / or rounded version ( ) thereof (e.g. of the inversed version of the previously computed second state variable value), if a symbol to be encoded takes a second value. This concept for the update of the second state variable value is substantially identical to the concept for the update of the first state variable value, wherein, for example, the same lookup table may be evaluated to save memory resources, and wherein, for example, a different scaling value when compared to the update of the first state variable value may be used, to thereby obtain a modified state variable value update characteristic. For example, different adaptation time constants for the first state variable value and for the state variable value may be obtained by using different scaling values for the determination of the updated first state variable value and the updated second state variable value. In a preferred embodiment, the arithmetic encoder is configured to apply a first scaling value (mk1), to scale the previously computed first state variable value (sk1), when determining an index of an entry of the lookup table to be evaluated when updating the first state variable value, and wherein the arithmetic encoder is configured to apply a second scaling value (mk2), to scale the previously computed second state variable value (sk2), when determining an index of an entry of the lookup table to be evaluated when updating the second state variable value, wherein the first scaling value is different from the second scaling value (and wherein the first and the second scaling values are preferably integer potencies of 2, and wherein a ratio between the first scaling value and the second scaling value is preferably FH240412PEP-2025112831.DOCX an integer potency if 2, and wherein the first scaling value and the second scaling value preferably differ by a factor of at least 8). By using different scaling values when determining an index of an entry of a lookup table to be evaluated when updating the first state variable value and when determining an index of an entry of the lookup table to be evaluated when updating the second state variable value, different adaptation time constants can be implemented efficiently, wherein the fundamental state variable value update algorithm and the used lookup table may be identical and wherein the only significant difference may be the choice of the scaling values. This allows for a very resource-saving implementation. In a preferred embodiment, the arithmetic encoder is configured to scale a value returned by an evaluation of the lookup table using a first scaling value (e.g. nk1) when updating the first state variable value, wherein the arithmetic encoder is configured to scale a value returned by an evaluation of the lookup table using a second scaling value (e.g. nk2) when updating the second state variable value, wherein the first scaling value is different from the second scaling value. The described different scaling of the value returned by the evaluation of the lookup table (e.g. of the selected lookup table entry) allows for an efficient implementation of different adaptation time constants when updating the first state variable value and the second state variable value. Furthermore, such scaling allows to use the same lookup table for the update of the first state variable value and for the update of the second state variable value, which helps to save memory resources. In a preferred embodiment, the arithmetic encoder is configured to determine one or more updated state variable values ^^^^^^according to wherein A is a lookup table (for example, comprising integer values), wherein z is a predetermined (constant) offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^are one or more weighting values. FH240412PEP-2025112831.DOCX It has been found that such an update mechanism for the state variable value can be implemented with high computational efficiency and provides reliable results. In the following, some embodiments will be described which can be used individually and in combination with any of the other embodiments disclosed herein. For example the embodiments described in the following can be uses in arithmetic encoders and in arithmetic decoders. Moreover, the embodiments can optionally be combined with embodiments defined in the claims, wherein aspects described here can optionally be introduced into any of the embodiments defined in the claims individually or taken in combination. Similarly, features defined in the claims may optionally be introduced into the following embodiments individually or taken in combinations. In a preferred embodiment, for example, one or more hypotheses ^^^^^^(for example, one or more state variable values) are used for each context model. Furthermore, for example, a counter ^^^^^^^^^^^^is maintained and initialized with a predetermined value ^^^^^^^^^^^^^^^^^^, forexample ^^^^^^^^^^^^^^^^^^ = 63 before encoding or decoding the first bin associated with contextmodel ^^. For example, after the encoding or decoding of a bin with context model ^^, the context model is updated as follows: If, for example, ^^^^^^^^^^^^is greater than 0, the update equation uses larger values for ^^^^^^for at least one hypothesis than if, for example, ^^^^^^^^^^^^is equal to 0. For example, after updatinga context model, ^^^^^^^^^^^^ is set to ^^^^^^(0, ^^^^^^^^^^^^ − 1). In other words, the counter is, forexample, reduced by 1 after updating a context model, for example, until it reaches 0. For example, this technique ensures that each context model (or at least one of the context models) uses a faster adaptation for the first few bins than for the remaining bins. In can, for example, improve the compression efficiency, for example, if context models are initialized with equal probability. An exemplary configuration (in accordance with a preferred embodiment) is as follows (wherein it should be noted that, optionally, one or more of the parameters, including the matrix A, could be changed): 1) The number of hypotheses per context model is, for example, 2. 2) For example, ^^ = {157, 143, 129, 115, 101, 87, 73, 59, 45, 35, 29, 23, 17, 13, 9, 5,4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 0}3) For example, ^^ = 16FH240412PEP-2025112831.DOCX 4) For example, let ^^^^^^^^^^^^^^^^^^^^be the number of bits sufficient to represent state ^^^^^^as a signed integer in 2's complement representation. 5) For example, ^^^^ 5−^^^^ = 2 ^^^^^^^^^^^^^^^^^^6) For example, let ^^^^^^^^^^^^^^^^^^^^^^be an adaptation rate parameter associated with hypothesis ^^^^^^. Another preferred embodiment is, for example, based on the previous exemplary configuration with the following further conditions (wherein it should be noted that, optionally, one or more of the parameters could be changed): 1) For example, ^^^^^^^^^^^^^^^^^^ = 632) For example, ^^^^^^^^^^^^^^^^^^0 = 10 Another preferred embodiment is, for example, based on the previous preferredembodiment with the following modifications. If, for example, ^^^^^^^^^^^^ > 0, then only is updated as described and ^^1^^is, for example, derived from the just updated ^^0^^, for example, according to ∙ 2^^^^^^^^^^^^^^^^^^1−^^^^^^^^^^^^^^^^^^0. For example (but not necessarily), theprocessing for countk=0 may remain unchanged with respect to the previously described embodiment. In a preferred embodiment, a combined state ^^^^is, for example, derived as follows: First, the number of bits necessary to represent ^^^^as signed integer in 2's complementrepresentation shall be ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ = 1 + ^^^^^^(^^^^^^^^^^^^^^^^^^0, ^^^^^^^^^^^^^^^^^^1).Then, for example, The combined state variable shall, for example, be converted into a LPS (less probable symbol) probability value (for example, represented as unsigned integer), for example, by employing a lookup table ProbLPSmapping, for example, with 2^^^^^^^^^^^^^^^^^^^^^^elements. FH240412PEP-2025112831.DOCX For example, the LPS probability in integer representation ^^^^^^^^^^^^^^^^^^^^ associated with the combined state ^^^^is then given as^^^^^^^^^^^^^^^^^^^^ = ProbLPSmapping[abs(^^^^ >> (stateBitsCombined − probLPSbits − 1))].For example, the probability ^^^^^^^^associated with ^^^^^^^^^^^^^^^^^^^^ is given as^^^^^^^^ = ^^^^^^^^^^^^^^^^^^^^ / 2^^^^^^^^^^^^^^^^+1where, for example, ^^^^^^^^^^^^^^^^ is the number of bits necessary to store elements of ProbLPSmapping as unsigned integers. The arithmetic coder may, for example, need to calculate the width of the two subintervals associated with the encoding or decoding a particular bin. For example, the width of the less probable symbols (or symbol) is denoted rangeLPS and it is, for example, derived as rangeLPS = (^^^^^^^^^^ ∙ ^^^^^^^^^^^^^^^^^^^^) >> (^^^^^^^^^^^^^^^^ + 1)Alternatively, a version of this equation with a more accurate rounding can, for example, be employed which is given as rangeLPS = (^^^^^^^^^^ ∙ ^^^^^^^^^^^^^^^^^^^^ + (1 << ^^^^^^^^^^^^^^^^)) >> (^^^^^^^^^^^^^^^^ + 1)For example, in order to ensure that rangeLPS is greater than 0, the following step may, for example, apply rangeLPS = max(1, rangeLPS)Next, as an example, the elements in lookup table ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ are derived. For example, the ^^-th element of ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ is calculated as follows (wherein round(.) is a rounding operation). ^^^^^^^^^^^^^^^^ = 212−^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ = 0.5 ∙ ^^^^∙^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ = round (^^^^^^^^^^^^^^^^^^ ∙ 2^^^^^^^^^^^^^^^^+1)^^^^^^^^^^^^^^^^^^^^^^^^^^^^[^^] = max(1, min( (1 << ^^^^^^^^^^^^^^^^) − 1, ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^)FH240412PEP-2025112831.DOCX Note that ^^ is a constant that controls the mapping of states to probabilities. An exemplary value for ^^ is 0.9989407902.For example, the last equation ensures that ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ is clipped to (1 <<^^^^^^^^^^^^^^^^) − 1. This ensures, for example, that ^^^^^^^^^^^^^^^^ bits are sufficient to storeelements of ^^^^^^^^^^^^^^^^^^^^^^^^^^^^. For example, without this clipping, it can happen that tableelements of ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ require ^^^^^^^^^^^^^^^^ + 1 bits.For example, in a preferred embodiment, ^^^^^^^^^^^^^^^^ is set to 11 and ^^^^^^^^^^^^^^^^^^^^^^ is set to 8.Thus, as an example, the look-up table ^^^^^^^^^^^^^^^^^^^^^^^^^^^^[ ] is:^^^^^^^^^^^^^^^^^^^^^^^^^^^^[ ]= [2047, 2014, 1980, 1946, 1914, 1882, 1850, 1819, 1788, 1758, 1729, 1700, 1671, 1643,1615, 1588, 1561, 1535, 1509, 1484, 1459, 1434, 1410, 1387, 1363, 1340, 1318, 1296,1274, 1252, 1231, 1211, 1190, 1170, 1151, 1131, 1112, 1094, 1075, 1057, 1039, 1022,1005, 988, 971, 955, 939, 923,908, 892, 877, 863, 848, 834, 820, 806, 792, 779, 766, 753,740, 728, 716, 704,692, 680, 669, 658, 647, 636, 625, 614, 604, 594, 584, 574, 564,555, 546, 537, 527, 519, 510, 501, 493, 485, 476, 468, 461, 453, 445, 438, 430, 423,416, 409, 402, 395, 389, 382, 376, 369, 363, 357, 351, 345, 339, 334, 328, 323,317,312,307, 301, 296, 291, 286, 282, 277, 272, 268, 263, 259, 254, 250, 246, 242, 238,234, 230, 226, 222, 218, 215, 211, 208, 204, 201, 197, 194, 191, 187, 184, 181,178, 175, 172, 169, 167, 164, 161, 158, 156, 153, 150, 148, 145, 143, 141, 138,136, 134, 131, 129, 127, 125, 123, 121, 119, 117, 115, 113, 111, 109, 107, 105,104, 102 100, 98, 97, 95, 94, 92, 90, 89, 87, 86, 85, 83, 82, 80,79, 78, 76, 75, 74, 73, 71, 70, 69, 68, 67, 66, 64, 63, 62, 61, 60, 59, 58, 57, 56, 55, 54, 53, 53, 52, 51, 50, 49, 48, 47, 47, 46, 45, 44, 44, 43, 42, 41, 41, 40, 39, 39, 38, 37, 37, 36, 36, 35, 34, 34, 33, 33, 32, 32, 31, 31, 30, 30, 29, 29, 28, 28, 27] To conclude, an aspect of the invention is related to a fast start for context models. Here, for example, the first 63 bins of a context model are adapted with a faster adaptation rate than the remaining (residual) bins. To further conclude, a second aspect of the invention is related to a clipping of a table for converting the state (e.g. a state variable value or a combined state variable value) into a probability (e.g. into an integer value representing a probability) in order to save one bit per FH240412PEP-2025112831.DOCX entry in the table. If, for example, the probability is multiplied with 2^11 (e.g.211) (or with 212) and saved in the table rounded to integer, a table entry of 2048 results for the maximum possible LPS (less-probably-symbol) probability (e.g. for a probability of 0.5). This would just not fit into 11 bits. Here, for example, the suggested clipping, for example, to 2047 becomes effective. For example, this falsifies the value by a minimal amount, but one saves 1 bit per value in the table representation. In a preferred embodiment, the arithmetic encoder is configured to determine one or more updated state variable values ^^^^^^according to wherein A is a lookup table (for example, comprising integer values), wherein z is a predetermined (constant) offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^are one or more weighting values. It has been found that such a mechanism for the update of the state variable value can also be very advantageous in some situations. In particular, it is not necessary to invert a floating point value, which may be computationally inefficient in some implementations, using such an approach. Thus, the present concept may bring along a very good resource efficiency in some circumstances. In a preferred embodiment, the arithmetic encoder is configured to determine one or more updated state variable values ^^^^^^according to wherein A is a lookup table (for example, comprising integer values), wherein z is a predetermined (constant) offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^are one or more weighting values. It has been found that this concept also brings along a particularly high computational efficiency and a good accuracy in some implementation environments. FH240412PEP-2025112831.DOCX In a preferred embodiment, the arithmetic encoder is configured to determine one or more updated state variable values ^^^^^^according to wherein A is a lookup table (for example, comprising integer values), wherein z is a predetermined (constant) offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^are one or more weighting values. It has been found that this concept also brings along advantages in terms of computational efficiency and reliability in some circumstances. In a preferred embodiment of the arithmetic encoder, the entries of A decrease monotonically with increasing lookup table index. Using such an approach, it can be reached that an approximation of the state variable value towards a maximum value or towards a minimum value is monotonous and / or continuous and / or asymptotic. For example, it can be reached that state variables which are far away from a respective maximum value or minimum value are modified towards the maximum value or towards the minimum value comparatively fast, while state variable values which are closer to the respective maximum value or minimum value are changed toward said maximum value or minimum value comparatively slower. Thus, the above-mentioned choice of the entries of the lookup table allows for a smooth approximation of the maximum values or minimum values, which has been found to be very helpful for the derivation of interval size information on the basis of the one more state variable values.In a preferred embodiment of the arithmetic encoder, A is ^^[^^ + ^̂^] = ^^^^^^^^^^^^ +∑^̂^ ^^=1 max(0, ^̂^^^ − ^̂^) <<^̂^^^or deviates therefrom merely for one or more extreme values of its argument by zero setting or magnitude reduction to avoid the updated ^^^^^^leaving a predetermined value range, (e.g. consider that ^^^^^^has a value domain larger than ^^^^^^∙ ^^^^^^; that is, ^^^^^^is quasi quantized onto for extreme values of may be modified by an unamended A according to above formula to leave its value domain; to avoid this, the entries corresponding to these extreme values might be reduced or zeroed), where ^^^^^^^^^^^^, ^̂^, ^̂^^^, and ^̂^^^are predetermined parameters (examples are set out above). FH240412PEP-2025112831.DOCX It has been found that such a choice of the lookup table Α brings along a particularly advantageous behavior of the state variable values which are updated using said lookup table A. In a preferred embodiment of the arithmetic encoder, a last entry of the lookup table (which is addressed when the first state variable value reaches a predetermined range of values which extends up to a maximum allowable value, or when the first state variable value exceeds a predetermined threshold value) is equal to zero. By using a last entry of the lookup table, which is equal to 0, it can easily be avoided that the updated state variable value exceeds a maximum value and / or a minimum value. In a preferred embodiment, the arithmetic encoder is configured to apply a clipping operation to the updated state variable values, to keep the updated and clipped state variable values within a predetermined range of values. Using such a mechanism, it can easily be prevented that a state variable value exceeds the predetermined range between a minimum value and a maximum value. Accordingly, it can be ensured that the state variable value takes “reasonable” values. In a preferred embodiment, the arithmetic encoder is configured to apply a clipping operation according to ^^^^^^ = ^^^^^^(^^^^^^(^^ ^^ ^^^^ , ℎ^^ ), ^^^^^^) to the updated state variable values, wherein ^^^^^^is a maximum allowed value for ^^^^^^, and wherein ℎ^^^^is a minimum allowed value for ^^^^^^. It has been found that such a clipping operation can be implemented in an efficient manner and avoids invalid state variable values. In a preferred embodiment, the arithmetic encoder is configured to apply different scaling values for different context models (for example, such that at least one of the scaling values differs between two different context models). FH240412PEP-2025112831.DOCX Using different scaling values for different context models, the different statistic characteristics of the different context models (which may be associated with different types of information and / or types of bit stream syntax elements) can be considered. By using different scaling values for the different context models, the update procedure for the state variable values can easily be adapted to different context models without fundamentally changing the underlying algorithm. Thus, appropriate scaling values can be obtained in a very efficient manner. In a preferred embodiment, the arithmetic encoder is configured to obtain the interval size information as defined in one of the above embodiments. It has been found that the concept for the update of the state variable values can be well- used in combination with the above-mentioned concept for the derivation of the interval size information. An embodiment according to the invention creates an arithmetic encoder for encoding a plurality of symbols having symbol values (e.g. binary values), wherein the arithmetic encoder is configured to derive an interval size value (RLPS) for an arithmetic encoding of one or more symbol values to be encoded on the basis of one or more state variable values (sik) (which are, for example, associated with a given context mode, indicated by index k), which represent statistics of a plurality of previously encoded symbol values (e.g. a sequence of binary values 0 and 1) (e.g. with different adaptation time constants) wherein the arithmetic encoder is configured to determine the interval size value (RLPS) using a base lookup table (Base TabLPS), (a dimension of which in terms of probability indices is smaller than a number of possible probability indices i), wherein the arithmetic encoder is configured to determine the interval size value (RLPS) such that a determined interval size value is identical to an element of the base lookup table or is a rounded version of an element of the base lookup table if a probability index (i), which is obtained on the basis of the one or more state variable values (for example, as i=Qp(pLPS)), is within a first range (e.g. smaller than µ), and such that a determined interval size value is obtained using a scaling and rounding of an element of the base lookup table if the probability index is within a second range (e.g. larger than or equal to µ); and wherein the arithmetic encoder is configured to perform the arithmetic encoding of one or more symbols using the interval size value (RLPS). This embodiment according to the invention is based on the idea that a determination of an interval size value in an arithmetic encoder can be performed using a “base lookup table”, FH240412PEP-2025112831.DOCX a dimension of which is smaller than a number of different interval size values associated with a given current coding interval size by re-using elements of said base lookup table, one time without a scaling and one time with a scaling. Accordingly, it can be exploited that interval size values for the arithmetic coding (encoding / decoding), which are associated with different ranges of state variable values, substantially differ by a scaling (for example, except for some rounding effect). Accordingly, a comparatively small “base lookup table” can be used, entries of which are used multiple times for different probability indices (wherein the probability indices may be derived on the basis of respective state variable values). To conclude, the concept described here allows for a highly efficient determination of the interval size values on the basis of one or more state variable values. In a preferred embodiment, the arithmetic encoder is configured to determine the interval size value, such that the determined interval size value (RLPS) is a right-shifted version of an element of the base-lookup table if the probability index is within the second range. This concept is based on the idea that a right-shifting operation is computationally very efficient, and also provides for reliable interval size values if the probability index is within the second range (while, preferably, no shift operation is applied to elements of the base lookup table if the probability index is within the first range). Consequently, interval size values provided for “corresponding” probability indices within the first range and within the second range mainly differ by a bit-shifting (except for a possible rounding). This is typically true over a range of probability index values, or even over the complete “first range” (which typically comprises more than two different values). Furthermore, it should be noted that the right-shift operation typically corresponds to a division by a potency of two. In a preferred embodiment, the probability index (Qp2(pLPS)) determines whether an element of the lookup table is provided as the interval size value (RLPS), or whether an element of the lookup table is scaled and rounded to obtain the interval size value (RLPS). Since the probability index (or, more specifically, the question whether the probability index is within the first range or within the second range) decides whether a scaling (and optionally a rounding) is applied to obtain the interval size value on the basis of an element of the lookup table (base lookup table), the algorithm can be kept very simple. For example, the check whether the probability index lies within the first range or within the second range can FH240412PEP-2025112831.DOCX easily be performed by a division of the probability index by a predetermined value, or by a comparison of the probability index with one or more threshold values. Accordingly, it can easily be decided, on the basis of the probability index, whether the scaling (and the optional rounding) should be performed or not. Thus, the concept for the derivation of the interval size value is very efficient. In a preferred embodiment of the arithmetic encoder, a division residual (i%µ) of a division between the probability index (i) and a first size value (e.g. µ; wherein the size value, for example, describes an extension of the base lookup table in a first direction) and an interval size index (which may, for example, be obtained on the basis on an interval size information or total interval size information R, for example using a quantization operation Qr2(.)) determine which element of the base lookup table is used to obtain the interval size value. By selecting an entry of the base lookup table in dependence on the division residual and also in dependence on the interval size index, a two dimensional base lookup table can easily be evaluated, wherein the elements of the two dimensional base lookup table may incorporate a multiplication with an interval size value (which may be represented by the interval size index). Thus, it is possible to save a multiplication with an interval size value by having a two dimension base lookup table (wherein the division residual may be used as a first table index and wherein the interval size index may serve as a second table index). Furthermore, usage of the division residual as the first table index is well-adapted to the fact that elements of the base lookup table are selected cyclically with increasing probability index (because subsequent ranges of the probability index select a common range of the base lookup table). To conclude, the above-mentioned implementation allows for a very simple access of an element of the base lookup table and helps to avoid a multiplication with an interval size value due to the two-dimensional nature of the base lookup table. In a preferred embodiment, the arithmetic encoder is configured to obtain the interval size value RXPS (e.g. RLPS) according to RXPS=Scal(BaseTabLPS[i%µ][j] , ⌊ i / µ ⌋) wherein BaseTabLPS is a base lookup table of dimension µ x λ; wherein i is a table index associated with a probability information; wherein j is a table index associated with an interval size information (e.g. the total interval size information R); wherein % is a division residual operation; wherein / is a division operation; wherein Scal (x,y) is a scaling function FH240412PEP-2025112831.DOCX (for example, defined as Scal (x,y)= ⌊x*a-by⌋, wherein ⌊. ⌋ is a floor operation, wherein a is preferably a constant larger than or equal to 2, and wherein b is preferably a constant larger than or equal to 1, and wherein the scaling function is preferable implemented using a shift- to-the -right bit shift operation, wherein y determines whether and by how many bits a shift- to-the-right of x is performed). It has been found that such a concept for the determination of the interval size value, which constitutes the interval size information, is highly computationally efficient and allows for the usage of a comparatively small base lookup table. In particular, multiplication operations can be avoided. Furthermore, the divisional residual operation and the division operation may also be implemented in a very computationally efficient manner, for example, if the dimension μ is a potency of 2. Thus, the described concept for the derivation of the interval size value allows for a computationally very efficient implementation. In a preferred embodiment, the arithmetic encoder is configured to derive an interval size value (RLPS) for an arithmetic encoding of one or more symbol values to be encoded on the basis of one or more state variable values (sik) (which are, for example, associated with a given context mode, indicated by index k), which represent statistics of a plurality of previously encoded symbol values (e.g. a sequence of binary values 0 and 1) (e.g. with different adaptation time constants); wherein the arithmetic encoder is configured to determine the interval size value (RLPS) using a probability table (Prob TabLPS), (a dimension of which in terms of probability indices is smaller than a number of possible probability indices i) on the basis of a (current) probability value derived from the one or more state variable values and on the basis of a (current) coding interval size (R), wherein the probability table describes interval sizes (interval size values) for a set of a plurality of probability values (for example, for probability indices between 0 and µ-1) and for a (single) given (reference) coding interval size, and wherein the arithmetic encoder is configured to scale an element of the probability table (Prob_TabLPS) (for example, an element selected in dependence on the current probability value), to obtain the interval size value[RLPS) if a current probability value is not in the set of a plurality of probability values (for example, is a probability index associated with the current probability value is larger than or equal to µ) and / or if a current coding interval size (R) is different from the given (reference) coding interval size; and wherein the arithmetic encoder is configured to perform the arithmetic encoding of one or more symbols using the interval size value (RLPS). FH240412PEP-2025112831.DOCX This concept is based on the idea that interval size values associated with different (non- overlapping) ranges of probability values (or probability indexes) are substantially (except for possible rounding effect) related by a scaling operation. It should also be noted that the scaling operation may, for example, be implemented in a computationally efficient manner, for example, using bit-shift operations, if the size of the lookup table (probability table) is chosen appropriately. Consequently, it is possible to derive the interval size value, which is used for the arithmetic coding (encoding or decoding) with small computational effort and also using only a small-size lookup table, which saves memory. In a preferred embodiment, the arithmetic encoder is configured to obtain an interval size value using a (multiplicative) first scaling of a selected element (probTabLPS[i%µ]) of the probability table in dependence on the (current) coding interval size (R), and using a second scaling of a result of the first scaling in dependence on whether an element associated with a current probability value (designated by index i) is included in the set of a plurality of probability values or not (e.g. in dependence on whether the current probability value lies within a range of probability values covered by the probability table or not). By using a two-step multiplication or scaling, to obtain the interval size information, allows the usage of a small probability table. For example, the probability table may only “directly” cover a single coding interval size and a given, comparatively small range of probability values (which may be represented by the “set of a plurality of probability values”). Accordingly, for any other coding interval sizes, and for any probability values which are not included in the set of a plurality of probability values which are “directly” covered by the probability table, a scaling is performed, such that meaningful and reliable interval size values are obtained. In a preferred embodiment of the arithmetic encoder, a division residual (i%µ) of a division between a probability index (e.g. i; e.g. representing the current probability value) and a first size value (e.g. µ; wherein the size value, for example, describes an extension of the probability table) determines which element of the probability table is scaled in the first scaling; and / or wherein an integer division result ( ⌊i / µ⌋ ) of a division between the probability index (i) and the first size value determines a scaling factor (2-⌊ i / µ ⌋) used in the second scaling; and / or wherein the coding interval size (R) determines a multiplicative scaling factor (Qr2(R)) of the first scaling. FH240412PEP-2025112831.DOCX Using a division residual to determine which element of the probability is scaled helps to exploit the fact that entries of the probability table are periodically reused with increasing probability index (e.g., in a cyclic manner). Usage of a division residual expresses this fact. Also, a division residual can, in some circumstances, be computed with very high computational efficiency, particularly if the division is made by a potency of two. Moreover, by determining the scaling factor on the basis of the integer division result allows to easily allocate scaling factors to different (adjacent) ranges of probability index values. Furthermore, the integer division result can, under some circumstances, be computed in a computationally highly efficient manner, in particular, if the division is made by a potency of two. Moreover, determining a multiplicative scaling factor in dependence on the coding interval size reflects the fact that the interval size value scales with the coding interval size. Accordingly, the interval size value can be obtained with high efficiency and accuracy. In a preferred embodiment, the arithmetic encoder is configured to obtain the interval size value RXPS (e.g. RLPS) according to RXPS = ^^^^^^^^(⌊^^^^^^^^^^^^^^^^^^^^[^^ % ^^] ∙ ^^^^2(^^)⌋, ⌊^^ / ^^⌋)wherein i is a table index associated with a probability information; wherein j is a table index associated with an interval size information; wherein % is a division residual operation; wherein / is a division operation; wherein probTabLPS[] is the probability table; wherein µ is a number of elements of the probability table (wherin a range of values of i is typically larger than µ); wherein R is an interval size (e.g. a current coding interval size); wherein Qr2(R) is a scaling factor which is dependent on R; wherein Scal (x,y) is a scaling function (for example, defined as Scal (x,y)= ⌊x*a-by⌋, wherein ⌊. ⌋ is a floor operation, wherein a is preferably a constant larger than or equal to 2, and wherein b is preferably a constant larger than or equal to 1, and wherein the scaling function is preferably implemented using a shift- to-the -right bit shift operation, wherein y determines whether and by how many bits a shift- to-the-right of x is performed). Such an algorithm for the determination of the interval size value has been found to be computationally efficient and to provide good quality results. The probability table can be FH240412PEP-2025112831.DOCX comparatively small, and the scaling function can be implemented in a computationally efficient manner, for example, using one or more bit shift operations. In a preferred embodiment, the arithmetic encoder is configured to obtain an interval size value using a (multiplicative) first scaling of a selected element (probTabLPS[i%µ]) of the probability table in dependence on whether an element associated with a current probability value (designated by index i) is included in the probability value or not (e.g. in dependence on whether the current probability value lies within a range of probability values covered by the probability table or not), and using a second scaling of a result of the first scaling in dependence on the coding interval size (R). In this concept, a processing order of the first scaling and of the second scaling is reversed when compared to the above-mentioned concept. However, the fundamental considerations remain the same. In a preferred embodiment, a division residual (i%µ) of a division between a probability index (e.g. i; e.g. representing the current probability value) and a first size value (e.g. µ; wherein the size value, for example, describes an extension of the probability table) determines which element of the probability table is scaled in the first scaling; and / or wherein an integer division result ( ⌊i / µ⌋ ) of a division between the probability index (i) and the first size value determines a scaling factor (e.g.2-⌊ i / µ ⌋ or a-b⌊ i / µ ⌋) used in the first scaling; and / or wherein the (current) coding interval size (R) determines a multiplicative scaling factor (Qr2(R)) of the second scaling. In this concept, the order of the first scaling and of the second scaling is reversed when compared to the above-mentioned concept. However, the fundamental considerations remain unchanged. In a preferred embodiment, the arithmetic encoder is configured to obtain the interval size value RXPS. (e.g. RLPS) according to RXPS = ⌊^^^^^^^^(^^^^^^^^^^^^^^^^^^^^[^^ % ^^], ⌊^^ / ^^⌋) ∙ ^^^^2(^^)⌋wherein i is a table index associated with a probability information; wherein j is a table index associated with an (current) interval size information; wherein % is a division residual FH240412PEP-2025112831.DOCX operation; wherein / is a division operation (e.g. providing an integer result); wherein probTabLPS[] is the probability table; wherein µ is a number of elements of the probability table (wherein a range of values of i is typically larger than µ); wherein R is an interval size (e.g. a current coding interval size); wherein Qr2(R) is a scaling factor which is dependent on R; wherein Scal (x,y) is a scaling function (for example, defined as Scal (x,y)= ⌊x*a-by⌋, wherein ⌊. ⌋ is a floor operation, wherein a is preferably a constant larger than or equal to 2, and wherein b is preferably a constant larger than or equal to 1, and wherein the scaling function is preferably implemented using a shift-to-the -right bit shift operation, wherein y determines whether and by how many bits a shift-to-the-right of x is performed). In this concept, the scaling order of the first scaling and of the second scaling is reversed when compared to the above-mentioned implementation. However, the fundamental underlying ideas remain unchanged. In the following, a number of embodiments will be described which are related to an arithmetic decoding. However, the ideas, considerations and details underlying these ideas, which are related to an arithmetic decoding, are substantially identical to the ideas, considerations and details underlying concepts for arithmetic encoding. Accordingly, the above explanations also apply in an analogous manner. However, symbol values to be encoded correspond to symbol values to be decoded or to previously decoded symbols, and previously encoded symbol values correspond to previously decoded symbol values. Moreover, a correspondence between encoding features and decoding features is apparent for the person skilled in the art and also apparent from a comparison of the claim wording. An embodiment according to the invention creates an arithmetic decoder for decoding a plurality of symbols having symbol values (e.g. binary values), wherein the arithmetic decoder is configured to derive an interval size value (RLPS) for an arithmetic decoding of one or more symbol values to be decoded on the basis of one or more state variable values (sik) (which are, for example, associated with a given context mode, indicated by index k), which represent statistics of a plurality of previously decoded symbol values (e.g. a sequence of binary values 0 and 1) (e.g. with different adaptation time constants), wherein the arithmetic decoder is configured to determine the interval size value (RLPS) using a base lookup table (Base TabLPS), (a dimension of which in terms of probability indices is smaller than a number of possible probability indices i), wherein the arithmetic decoder is configured to determine the interval size value (RLPS) such that a determined interval size value is identical to an element of the base lookup table or is a rounded version of an element of the FH240412PEP-2025112831.DOCX base lookup table if a probability index (i), which is obtained on the basis of the one or more state variable values (for example, as i=Qp(pLPS)), is within a first range (e.g. smaller than µ), and such that a determined interval size value is obtained using a scaling and rounding of an element of the base lookup table if the probability index is within a second range (e.g. larger than or equal to µ); and wherein the arithmetic decoder is configured to perform the arithmetic decoding of one or more symbols using the interval size value (RLPS). In a preferred embodiment, the arithmetic decoder is configured to determine the interval size value, such that the determined interval size value (RLPS) is a right-shifted version of an element of the base-lookup table if the probability index is within the second range. In a preferred embodiment of the arithmetic decoder, the probability index (Qp2(pLPS)) determines whether an element of the lookup table is provided as the interval size value (RLPS), or whether an element of the lookup table is scaled and rounded to obtain the interval size value (RLPS). In a preferred embodiment of the arithmetic decoder, a division residual (i%µ) of a division between the probability index (i) and a first size value (e.g. µ; wherein the size value, for example, describes an extension of the base lookup table in a first direction) and an interval size index (which may, for example, be obtained on the basis on an interval size information or total interval size information R, for example using a quantization operation Qr2(.)) determine which element of the base lookup table is used to obtain the interval size value. In a preferred embodiment, the arithmetic decoder is configured to obtain the interval size value RXPS (e.g. RLPS) according to RXPS=Scal(BaseTabLPS[i%µ][j) , ⌊ i / µ ⌋) wherein BaseTabLPS is a base lookup table of dimension µ x λ; wherein i is a table index associated with a probability information; wherein j is a table index associated with an interval size information (e.g. the total interval size information R); wherein % is a division residual operation; wherein / is a division operation; wherein Scal (x,y) is a scaling function (for example, defined as Scal (x,y)= ⌊x*a-by⌋, wherein ⌊. ⌋ is a floor operation, wherein a is preferably a constant larger than or equal to 2, and wherein b is preferably a constant larger than or equal to 1, and wherein the scaling function is perferable implemented using a shift- FH240412PEP-2025112831.DOCX to-the -right bit shift operation, wherein y determines whether and by how many bits a shift- to-the-right of x is performed). An embodiment according to the invention creates an arithmetic decoder for decoding a plurality of symbols having symbol values (e.g. binary values), wherein the arithmetic decoder is configured to derive an interval size value (RLPS) for an arithmetic decoding of one or more symbol values to be decoded on the basis of one or more state variable values (sik) (which are, for example, associated with a given context mode, indicated by index k), which represent statistics of a plurality of previously decoded symbol values (e.g. a sequence of binary values 0 and 1) (e.g. with different adaptation time constants); wherein the arithmetic decoder is configured to determine the interval size value (RLPS) using a probability table (Prob TabLPS), (a dimension of which in terms of probability indices is smaller than a number of possible probability indices i) on the basis of a (current) probability value derived from the one or more state variable values and on the basis of a (current) coding interval size (R), wherein the probability table describes interval sizes (interval size values) for a set of a plurality of probability values (for example, for probability indices between 0 and µ-1) and for a (single) given (reference) coding interval size, and wherein the arithmetic decoder is configured to scale an element of the probability table (Prob_TabLPS) (for example, an element selected in dependence on the current probability value), to obtain the interval size value[RLPS) if a current probability value is not in the set of a plurality of probability values (for example, is a probability index associated with the current probability value is larger than or equal to µ) and / or if a current coding interval size (R) is different from the given (reference) coding interval size; and wherein the arithmetic decoder is configured to perform the arithmetic decoding of one or more symbols using the interval size value (RLPS). In a preferred embodiment, the arithmetic decoder is configured to obtain an interval size value using a (multiplicative) first scaling of a selected element (probTabLPS[i%µ]) of the probability table in dependence on the (current) coding interval size (R), and using a second scaling of a result of the first scaling in dependence on whether an element associated with a current probability value (designated by index i) is included in the set of a plurality of probability values or not (e.g. in dependence on whether the current probability value lies within a range of probability values covered by the probability table or not). In a preferred embodiment of the arithmetic decoder, a division residual (i%µ) of a division between a probability index (e.g. i; e.g. representing the current probability value) and a first FH240412PEP-2025112831.DOCX size value (e.g. µ; wherein the size value, for example, describes an extension of the probability table) determines which element of the probability table is scaled in the first scaling; and / or wherein an integer division result ( ⌊i / µ⌋ ) of a division between the probability index (i) and the first size value determines a scaling factor (2-⌊ i / µ ⌋) used in the second scaling; and / or wherein the coding interval size (R) determines a multiplicative scaling factor (Qr2(R)) of the first scaling. In a preferred embodiment, the arithmetic decoder is configured to obtain the interval size value RXPS (e.g. RLPS) according to RXPS = ^^^^^^^^(⌊^^^^^^^^^^^^^^^^^^^^[^^ % ^^] ∙ ^^^^2(^^)⌋, ⌊^^ / ^^⌋)wherein i is a table index associated with a probability information; wherein j is a table index associated with an interval size information; wherein % is a division residual operation; wherein / is a division operation; wherein probTabLPS[] is the probability table; wherein µ is a number of elements of the probability table (wherin a range of values of i is typically larger than µ); wherein R is an interval size (e.g. a current coding interval size); wherein Qr2(R) is a scaling factor which is dependent on R; wherein Scal (x,y) is a scaling function (for example, defined as Scal (x,y)= ⌊x*a-by⌋, wherein ⌊. ⌋ is a floor operation, wherein a is preferably a constant larger than or equal to 2, and wherein b is preferably a constant larger than or equal to 1, and wherein the scaling function is preferably implemented using a shift- to-the -right bit shift operation, wherein y determines whether and by how many bits a shift- to-the-right of x is performed). In a preferred embodiment, the arithmetic decoder is configured to obtain an interval size value using a (multiplicative) first scaling of a selected element (probTabLPS[i%µ]) of the probability table in dependence on whether an element associated with a current probability value (designated by index i) is included in the probability value or not (e.g. in dependence on whether the current probability value lies within a range of probability values covered by the probability table or not), and using a second scaling of a result of the first scaling in dependence on the coding interval size (R). In a preferred embodiment of the arithmetic decoder, a division residual (i%µ) of a division between a probability index (e.g. i; e.g. representing the current probability value) and a first size value (e.g. µ; wherein the size value, for example, describes an extension of the probability table) determines which element of the probability table is scaled in the first FH240412PEP-2025112831.DOCX scaling; and / or wherein an integer division result ( ⌊i / µ⌋ ) of a division between the probability index (i) and the first size value determines a scaling factor (e.g.2-⌊ i / µ ⌋or a-b⌊ i / µ ⌋) used in the first scaling; and / or wherein the (current) coding interval size (R) determines a multiplicative scaling factor (Qr2(R)) of the second scaling. In a preferred embodiment, the arithmetic decoder is configured to obtain the interval size value RXPS (e.g. RLPS) according to RXPS = ⌊^^^^^^^^(^^^^^^^^^^^^^^^^^^^^[^^ % ^^], ⌊^^ / ^^⌋) ∙ ^^^^2(^^)⌋wherein i is a table index associated with a probability information; wherein j is a table index associated with an (current) interval size information; wherein % is a division residual operation; wherein / is a division operation (e.g. providing an integer result); wherein probTabLPS[] is the probability table; wherein µ is a number of elements of the probability table (wherein a range of values of i is typically larger than µ); wherein R is an interval size (e.g. a current coding interval size); wherein Qr2(R) is a scaling factor which is dependent on R; wherein Scal (x,y) is a scaling function (for example, defined as Scal (x,y)= ⌊x*a-by⌋, wherein ⌊. ⌋ is a floor operation, wherein a is preferably a constant larger than or equal to 2, and wherein b is preferably a constant larger than or equal to 1, and wherein the scaling function is preferably implemented using a shift-to-the -right bit shift operation, wherein y determines whether and by how many bits a shift-to-the-right of x is performed). In the following, some further embodiments which are related to an arithmetic encoding will be discussed. An embodiment according to the invention creates an arithmetic encoder for encoding a plurality of symbols having symbol values (e.g. binary values), wherein the arithmetic encoder is configured to determine one state variable value (sk), which represents a statistic of a plurality of previously encoded symbol values, and wherein the arithmetic encoder is configured to compute from the combined state variable value, or the scaled and / or rounded version ( ⌊sk* ak⌋ ) thereof, a subinterval width value (^^^^^^^^) for an arithmetic encoding of a symbol value to be encoded by mapping the one state variable value (sk), or a scaled and / orrounded version thereof ( ⌊sk* ak ⌋; ⌊|^^^^| ∙ ^^^^⌋) using a one-dimensional look-up table(^^^^^^^^^^^^^^^^^^^^[^^^^2(… )]) entries of which comprise probability values for different valueFH240412PEP-2025112831.DOCX intervals of a value domain for the combined state variable value, or the scaled and / orrounded version ( ⌊sk* ak ⌋; ⌊|^^^^| ∙ ^^^^⌋) thereof, onto a probability value, and quantizing acoding interval size information (e.g. R) describing a size of a coding interval of the arithmetic encoding before the arithmetic encoding of the symbol value to be encoded onto a quantization level (^^^^2(^^)); determine a product (either by look-up of precomputed products, or by multiplication) between the probability value and the quantization level, wherein the arithmetic encoder is configured to perform a state variable value update in dependence on the symbol value to be encoded. This embodiment is based on the finding that a very simple, one dimensional lookup table can be used for the determination of a subinterval width value on the basis of a combined state variable value. The coding interval size is considered by the quantization of the coding interval size information, and by the determination of a product between the probability value and the quantization value (or quantization level). Accordingly, reliable results are obtained with moderate effort. In a preferred embodiment, the arithmetic encoder is configured to derive as the one state variable value (sk) a combined state variable value (which may, for example, be a weighted sum of state variable values) one the basis of a plurality of state variable values (sik) (e.g. a sequence of binary values 0 and 1) (for example, in the case of a plurality of state variable values, statistics with different adaptation time constants), which represent statistics of the plurality of previously encoded symbol values (e.g. a sequence of binary values 0 and 1) with different adaptation time constants. It has been found that using a combined state variable value as the one state variable value brings along particularly good results. The consideration of different adaptation time constants allows for the consideration of both short time statistics and longtime statistics, which makes the subinterval width value particularly reliable. In a preferred embodiment, the arithmetic encoder is configured to determine a weighted sum of state variable values, in order to obtain the combined state variable value. Such a computation of the combined state variable value allows for a consideration of the different impact of short term statistics and long term statistics onto the combined state variable value while keeping a computation effort reasonably small. FH240412PEP-2025112831.DOCX In a preferred embodiment, the arithmetic encoder is configured to determine a sum of rounded values ( ∙ ^^^^^^⌋), which are obtained by rounding products of state variable values and associated weight values in order to obtain the combined state variable value (sk). Applying a rounding operation before the summation reduces the computational effort and also eliminates an impact of very small products of a state variable value and an associated weight value. Thus, a reliability is increased. In a preferred embodiment, the arithmetic encoder is configured to determine the combined state variable value skaccording to wherein sk2 are state variable values, wherein N is a number of state variable values considered, wherein ⌊ . ⌋ is a floor operator, wherein dki are weighting values associated with the state variable values (for example, weighting factors that control the influence of the individual state variable values onto the combined state variable value) (wherein dki are preferably integer-valued potencies of von 2, and wherein a ratio between two different dki is preferably an integer-valued potency of 2)[wherein a ratio between two different dki is preferably larger than or equal to 8). It has been found that such a derivation of the combined state variable value is particularly advantageous. Reference is also made to the above explanation of the corresponding concept for the determination of the combined state variable value. In a preferred embodiment, the arithmetic encoder is configured to, in performing the state variable value update, update the plurality of state variable values ^^^^^^according to wherein z is a predetermined (constant) offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^ are one or more weighting values, wherein A is ^^[^^ + ^̂^] = ^^^^^^^^^^^^ +FH240412PEP-2025112831.DOCX or deviates therefrom merely for one or more extreme values of its argument by zero setting or magnitude reduction to avoid the updated ^^^^^^leaving a predetermined value range, (e.g. consider that ^^^^^^has a value domain larger than ^^^^^^∙ ^^^^^^; that is, ^^^^^^is quasi quantized onto for extreme values of ^^^^^^ ∙ ^^^^^^, ^^^^^^may be modified by an unamended A according to above formula to leave its value domain; to avoid this, the entries corresponding to these extreme values might be reduced or zeroed); where ^^^^^^^^^^^^, ^̂^, ^̂^^^, and ^̂^^^are predetermined parameters (examples are set out above). It has been found that such an update of the state variable values is particularly advantageous. Reference is also made to the above explanations with respect to this concept for the update of the state variables.In a preferred embodiment, the arithmetic encoder is configured to derive ^^[^^ + by table look-up or computationally. Regarding this concept, reference is made to the above explanations. In a preferred embodiment, the arithmetic encoder is configured to determine one or more updated state variable values ^^^^^^according to wherein A is a lookup table (for example, comprising integer values), wherein z is a predetermined (constant) offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^are one or more weighting values. Regarding advantages of this concept for the update of one or more state variable values, reference is made to the above explanations. In a preferred embodiment, the arithmetic encoder is configured to determine one or more updated state variable values ^^^^^^according to FH240412PEP-2025112831.DOCX wherein A is a lookup table (for example, comprising integer values), wherein z is a predetermined (constant) offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^are one or more weighting values. Regarding advantages of this concept for the update of the one or more state variable values, reference is made to the above explanations. In a preferred embodiment, the arithmetic encoder is configured to determine one or more updated state variable values ^^^^^^according to wherein A is a lookup table (for example, comprising integer values), wherein z is a predetermined (constant) offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^are one or more weighting values. Regarding advantages of this concept for the update of one or more state variable values, reference is made to the above explanations. In a preferred embodiment, the arithmetic encoder is configured to perform the quantizing the coding interval size information by applying a logical right shift onto the coding interval size information. A logical right shift of the coding interval size information is computationally highly efficient. In a preferred embodiment, the arithmetic encoder is configured to perform the quantizingthe coding interval size information ^^ by ^^^^2(^^) = (⌊^^ ∙ 2−^^⌋ + ^^) ∙ 2−^^, where ^^, ^^ and ^^are parameters. Regarding advantages of this quantization of the coding interval size information, reference is made to the above discussion. FH240412PEP-2025112831.DOCX In a preferred embodiment of the arithmetic encoder, the entries of the one-dimensional look-up table monotonically decrease at an increase of the one state variable value, or the scaled and / or rounded version ( ⌊sk* ak⌋ ) thereof. Regarding advantages of this structure of the one-dimensional lookup table, reference is made to the above discussion. In a preferred embodiment of the arithmetic encoder, different value intervals of the value domain for the one state variable value, or the scaled and / or rounded version ( ⌊sk* ak⌋ ) thereof, are equally sized. Regarding advantages of this concept, reference is made to the above discussion. In a preferred embodiment of the arithmetic encoder, the entries of the one-dimensional look-up table monotonically decrease with decreasing rate at an increase of the one state variable value, or the scaled and / or rounded version ( ⌊sk* ak⌋ ) thereof. Regarding advantages of this concept, reference is made to the above discussion. In the following, concepts for an arithmetic decoding will be described which correspond to the above-discussed concepts for the arithmetic encoding. Accordingly, the same explanations also apply, and the same details described above can optionally be used. However, it should be noted that an arithmetic encoder corresponds to an arithmetic decoder. Moreover, previously encoded symbol values typically correspond to previously decoded symbol values, and symbol values to be encoded may typically correspond to previously decoded symbol values (or to symbol values to be decoded). However, regarding the correspondence of features, reference is also made to a comparison on the corresponding claims defining related (or corresponding) concepts. An embodiment according to the invention creates an arithmetic decoder for decoding a plurality of symbols having symbol values (e.g. binary values), wherein the arithmetic decoder is configured to derive an interval size information (pk, R*pk) for an arithmetic decoding of one or more symbol values to be decoded on the basis of a plurality of state variable values (sik) (which are, for example, associated with a given context model, indicated by index k), which represent statistics of a plurality of previously decoded symbol values (e.g. a sequence of binary values 0 and 1)[for example, an estimate of a probabilities FH240412PEP-2025112831.DOCX that one or more symbols to be decoded comprises certain symbol values) with different adaptation time constants, wherein the arithmetic decoder is configured to map a first state variable value (sk1), or a scaled and / or rounded version ( ⌊sk1* ak1⌋ ) thereof, using a lookup- table (LUT1) and to map a second state variable value (sk2), or a scaled and / or rounded version ( ⌊sk2* ak2⌋ ) thereof using the lookup-table (LUT1), in order to obtain the interval size information (e.g. pk or R*pk) describing an interval size for the arithmetic decoding of one or more symbols to be decoded. In a preferred embodiment, the arithmetic decoder is configured to map the first state variable value, or the scaled and / or rounded version ( ⌊sk1* ak1 ⌋ ) thereof, onto a first probability value (pk1) using the look-up table, and wherein the arithmetic decoder is configured to map the second state variable value, or the scaled and / or rounded version ( ⌊sk2* ak2⌋ ) thereof, onto a second probability value (pk2) using the look-up table, and wherein the arithmetic decoder is configured to obtain a combined probability value (pk) using the first probability value and the second probability value (for example, using a weighted summation or using a weighted averaging). In a preferred embodiment, the arithmetic decoder is configured to change the state variable value into a first direction (e.g. to become more positive) if a decoded symbol takes a first value (e.g. “1”), and to change the state variable value into a second direction (e.g. to become more negative) if a decoded symbol takes a second value (e.g. “0”) which is different from the first value (for example, such that the state variable value can take positive and negative values), wherein the arithmetic decoder is configured to determine an entry of the lookup-table to be evaluated in dependence on an absolute value (skiif ski>0, -skiotherwise) of a respective state variable value (e.g in dependence on a scaled and rounded version of an absolute value of the state variable value). In a preferred embodiment, the arithmetic decoder is configured to set a first probability value (pk1) to a value provided by the lookup table ) if the first state variable value takes a first sign (e.g. a positive sign), and wherein the arithmetic decoder is configured to set the first probability value (pk1) to a value obtained by subtracting a valueprovided by the lookup table (e.g. to 1 ) from a predetermined value (e.g.1) if the first state variable value takes a second sign (e.g. a negative sign). In a preferred embodiment, the arithmetic decoder is configured to determine two or more probability values pki according to FH240412PEP-2025112831.DOCX wherein LUT1 is a lookup-table containing probability values; wherein ⌊ . ⌋ is a floor operator; wherein ski is an i-th state variable value; and wherein aki is a weighting value associated with the i-th state variable value (for example, a weighting value that adapts a number range of the i-th state variable value to a number of entries of the lookup-table). In a preferred embodiment, the arithmetic decoder is configured to determine two or more probability values pki according to wherein LUT1 is a lookup-table containing probability values; wherein ⌊ . ⌋ is a floor operator; wherein skiis an i-th state variable value; and wherein akiis a weighting value associated with the i-th state variable value (for example, a weighting value that adapts a number range of the i-th state variable value to a number of entries of the lookup-table). In a preferred embodiment, the arithmetic decoder is configured to obtain a combined probability value pkon the basis of a plurality of probability values pki according to wherein N is a number of probability values considered (and may be equal to a number of state variable values considered); and wherein bkiis a weighting value (for example, a weighting factor that controls an influence of individual state variable values onto the combined probability value)[wherein bki are preferably integer-valued potencies of von 2, and wherein a ratio between two different bkiis preferably an integer-valued potency of 2) In a preferred embodiment, the arithmetic decoder is configured to map the first state variable value, or the scaled and / or rounded version ( ⌊sk1* ak1⌋ ) thereof, onto a first subinterval width value (R*pk1) using a two-dimensional look-up table, entries of which are FH240412PEP-2025112831.DOCX addressed in dependence on the first state variable value (e.g. to determine a first lookup table entry coordinate) and in dependence on a coding interval size information (e.g. R) describing a size of a coding interval of the arithmetic decoding before a decoding of a symbol (e.g. to determine a second lookup table entry coordinate), wherein the arithmetic decoder is configured to map the second state variable value, or the scaled and / or rounded version ( ⌊sk1* ak1⌋ ) thereof, onto a second subinterval width value (R*pk2) using the two-dimensional look-up table, entries of which are addressed in dependence on the second state variable value (e.g. to determine a first lookup table entry coordinate) and in dependence on a coding interval size information (e.g. R) describing a size of a coding interval of the arithmetic decoding before a decoding of a symbol (e.g. to determine a second lookup table entry coordinate); wherein the arithmetic decoder is configured to obtain a combined subinterval width value using the first subinterval width value and the second subinterval width value (for example, using a weighted summation or using a weighted averaging). In a preferred embodiment of the arithmetic decoder, the two-dimensional look-up table is representable as a dyadic product between a first one-dimensional vector (forming a one- dimensional look-up table) entries of which comprise probability values for different value intervals of a value domain for the first and second state variable values, or the scaledand / or rounded version ( ⌊sk* ak ⌋; |^^^^| ∙ ^^^^) thereof, and a second one-dimensional vector(^^^^2(^^)) entries of which comprise quantization levels for the coding interval size information. In a preferred embodiment of the arithmetic decoder, elements of the two-dimensional lookup-table (RangTabLPS) are defined on the basis of a base lookup table (Base TabLPS), wherein a first group (or block; e.g. an “upper half”) of the elements of the two-dimensional lookup-table are identical to elements of the base lookup-table or are rounded versions of elements of the base lookup table, and wherein a second group, (or block; e.g. a “lower half”) of the elements of the two-dimensional lookup-table are scaled and rounded versions of elements of the base lookup-table. In a preferred embodiment of the arithmetic decoder, the second group of elements of the two-dimensional lookup-table are right-shifted versions of elements of the base-lookup table. FH240412PEP-2025112831.DOCX In a preferred embodiment of the arithmetic decoder, a probability index (Qp2(pLPS) or i) determines whether an element of the first group of elements of the two-dimensional lookup table or an element of a second group of elements of the two-dimensional lookup table is evaluated, wherein a first range (for example, between 0 and µ-1) of probability indices (which are, for example, obtained by quantizing a probability value, e.g. pLPS) is associated with elements of the first group of elements, and wherein a second range (for example, larger than or equal to µ) of probability indices (which are, for example, obtained by quantizing a probability value, e.g. pLPS, e.g. using a quantization function Qp2(.)) is associated with elements of the second group of elements. In a preferred embodiment of the arithmetic decoder, a division residual (i%µ) of a division between the probability index (i) and a first size value (e.g. µ; wherein the size value, for example, describes an extension of the base lookup table in a first direction) and an interval size index (which may, for example, be obtained on the basis on an interval size information R, for example using a quantization operation Qr2(.); for example, j) determine which element of the base lookup table is used to obtain the element of two-dimensional lookup table. In a preferred embodiment, the arithmetic decoder is configured to obtain an element of the two-dimensional lookup-table (RangTabLPS) according to RangeTabLPS[i][j]=Scal(BaseTabLPS[i%µ][j) , ⌊i / µ⌋) wherein BaseTabLPS is a base lookup table of dimension µ x λ; wherein i is a table index associated with a probability information; wherein j is a table index associated with an interval size information (e.g. describing a current coding interval size); wherein % is a division residual operation; wherein / is a division operation; wherein Scal (x,y) is a scaling function (for example, defined as Scal (x,y)= ⌊x*a-by⌋, wherein ⌊. ⌋ is a floor operation, wherein a is preferably a constant larger than or equal to 2, and wherein b is preferably a constant larger than or equal to 1, and wherein the scaling function is preferably implemented using a shift-to-the -right bit shift operation, wherein y determines whether and by how many bits a shift-to-the-right of x is performed). In a preferred embodiment of the arithmetic decoder, elements of the two-dimensional lookup-table (RangTabLPS) are defined on the basis of a probability table (probTabLPS), wherein the probability table describes interval sizes for a set of a plurality of probability FH240412PEP-2025112831.DOCX values (for example, represented by indices i) and for a given (reference) coding interval size, and wherein elements of the two-dimensional lookup-table for a probability value which is not in the set of a plurality of probability values and / or for a coding interval size which is different from the given coding interval size are derived from the probability table using a scaling. In a preferred embodiment of the arithmetic decoder, elements of the two-dimensional lookup-table are obtained using a (multiplicative) first scaling of a selected element (probTabLPS[i%µ]) of the probability table in dependence on the coding interval size (R), and using a second scaling of a result of the first scaling in dependence on whether an element associated with a current probability value (designated by index i) is included in the set of probability values or not (e.g. in dependence on whether the current probability value lies within a range of probability values covered by the probability table or not). In a preferred embodiment of the arithmetic decoder, a division residual (i%µ) of a division between a probability index (e.g. i; e.g. representing the current probability value) and a first size value (e.g. µ; wherein the size value, for example, describes an extension of the probability table) determines which element of the probability table is scaled in the first scaling; and / or wherein an integer division result (⌊i / µ⌋) of a division between the probability index (i) and the first size value determines a scaling factor (2-⌊ i / µ ⌋) used in the second scaling; and / or wherein the coding interval size determines a multiplicative scaling factor (Qr2(R)) of the first scaling. In a preferred embodiment, the arithmetic decoder is configured to obtain an element ^^^^^^^^^^^^^^^^^^^^^^[^^][^^]of the two-dimensional lookup-table according to ^^^^^^^^^^^^^^^^^^^^^^[^^][^^] = ^^^^^^^^(⌊^^^^^^^^^^^^^^^^^^^^[^^ % ^^] ∙ ^^^^2(^^)⌋, ⌊^^ / ^^⌋)wherein i is a table index associated with a probability information; wherein j is a table index associated with an interval size information; wherein % is a division residual operation; wherein / is a division operation; wherein probTabLPS[] is the probability table; wherein µ is a number of elements of the probability table (wherein a range of values of I is typically larger than µ); wherein R is an interval size (or a current coding interval size); wherein Qr2(R) is a scaling factor which is dependent on R; wherein Scal (x,y) is a scaling function (for example, defined as Scal (x,y)= ⌊x*a-by⌋, wherein ⌊. ⌋ is a floor operation, wherein a is preferably a constant larger than or equal to 2, and wherein b is preferably a constant larger FH240412PEP-2025112831.DOCX than or equal to 1, and wherein the scaling function is preferably implemented using a shift- to-the -right bit shift operation, wherein y determines whether and by how many bits a shift- to-the-right of x is performed). In a preferred embodiment of the arithmetic decoder, elements of the two-dimensional lookup-table are obtained using a (multiplicative) first scaling of a selected element (probTabLPS[i%µ]) of the probability table in dependence on whether an element associated with a current probability value (designated by index i) is included in the set of probability values or not (e.g. in dependence on whether the current probability value lies within a range of probability values covered by the probability table or not) and using a second scaling of a result of the first scaling in dependence on the coding interval size (R). In a preferred embodiment of the arithmetic decoder, a division residual ( ⌊i%µ⌋ ) of a division between a probability index (e.g. i; e.g. representing the current probability value) and a first size value (e.g. µ; wherein the size value, for example, describes an extension of the probability table) determines which element of the probability table is scaled in the first scaling; and / or wherein an integer division result (⌊i / µ⌋) of a division between the probability index (i) and the first size value determines a scaling factor (2-⌊ i / µ ⌋) used in the first scaling; and / or wherein the coding interval size (R) determines a multiplicative scaling factor (Qr2(R)) of the second scaling. In a preferred embodiment, the arithmetic decoder is configured to obtain an element ^^^^^^^^^^^^^^^^^^^^^^[^^][^^]of the two-dimensional lookup-table according to ^^^^^^^^^^^^^^^^^^^^^^[^^][^^] = ⌊^^^^^^^^(^^^^^^^^^^^^^^^^^^^^[^^ % ^^], ⌊^^ / ^^⌋) ∙ ^^^^2(^^)⌋wherein i is a table index associated with a probability information; wherein j is a table index associated with an interval size information; wherein % is a division residual operation; wherein / is a division operation (e.g. providing an integer result); wherein probTabLPS[] is the probability table; wherein µ is a number of elements of the probability table (wherein a range of values of I is typically larger than µ); wherein R is an interval size; wherein Qr2(R) is a scaling factor which is dependent on R; wherein Scal (x,y) is a scaling function (for example, defined as Scal (x,y)= ⌊x*a-by⌋, wherein ⌊. ⌋ is a floor operation, wherein a is preferably a constant larger than or equal to 2, and wherein b is preferably a constant larger than or equal to 1, and wherein the scaling function is preferably implemented using a shift- FH240412PEP-2025112831.DOCX to-the -right bit shift operation, wherein y determines whether and by how many bits a shift- to-the-right of x is performed). In a preferred embodiment, the arithmetic decoder is configured to compute from the first and second state variable values, or the scaled and / or rounded version ( ⌊sk* ak⌋ ) thereof, first and second subinterval width values (R*pk), respectively, by mapping the first and second state variable values (sk), or a scaled and / or rounded version thereof ( ⌊sk2* ak2⌋ ) using a one-dimensional look-up table (LUT4) entries of which comprise probability values for different value intervals of a value domain for the first and second state variable values, or the scaled and / or rounded version ( ⌊sk* ak⌋ ) thereof, onto a first and second probability value, and quantizing a coding interval size information (e.g. R) describing a size of a coding interval of the arithmetic encoding before an encoding of a symbol onto a quantization level; determine products (either by look-up of precomputed products, or by multiplication) between the first and second probability value, on the one hand, and the quantization level, and obtaining a combined subinterval width value using the first subinterval width value and the second subinterval width value (for example, using a weighted summation or using a weighted averaging). In a preferred embodiment, the arithmetic decoder is configured to perform the quantizing the coding interval size information by applying a logical right shift onto the coding interval size information. In a preferred embodiment, the arithmetic decoder is configured to perform the quantizingthe coding interval size information ^^ by ^^^^2(^^) = (⌊^^ ∙ 2−^^⌋ + ^^) ∙ 2−^^, where ^^, ^^ and ^^are parameters. In a preferred embodiment of the arithmetic decoder, the entries of the one-dimensional look-up table monotonically decrease at an increase of the first and second state variable values, or the scaled and / or rounded version ( ⌊sk* ak⌋ ) thereof. In a preferred embodiment of the arithmetic decoder, different value intervals of the value domain for the first and second state variable value, or the scaled and / or rounded version ( ⌊sk* ak⌋ ) thereof, are equally sized. FH240412PEP-2025112831.DOCX In a preferred embodiment of the arithmetic decoder, the entries of the one-dimensional look-up table monotonically decrease with decreasing rate at an increase of the first and second state variable values, or the scaled and / or rounded version ( ⌊sk* ak⌋ ) thereof. An embodiment according to the invention creates an arithmetic decoder for decoding a plurality of symbols having symbol values (e.g. binary values), wherein the arithmetic decoder is configured to derive an interval size information (pk, R*pk) for an arithmetic decoding of one or more symbol values to be decoded on the basis of a plurality of state variable values (sik) (which are, for example, associated with a given context mode, indicated by index k), which represent statistics of a plurality of previously decoded symbol values (e.g. a sequence of binary values 0 and 1) (for example, an estimate of a probabilities that one or more symbols to be decoded comprises certain symbol values) with different adaptation time constants, wherein the arithmetic decoder is configured to derive a combined state variable value (sk) (which may, for example, be a weighted sum of state variable values) one the basis of the plurality of (individual) state variable values (sik), and wherein the arithmetic decoder is configured to map the combined state variable value (sk), or a scaled and / or rounded version thereof ( ⌊sk2* ak2⌋ ) using a look-up table, in order to obtain the interval size information (e.g. pk or R*pk) describing an interval size for the arithmetic decoding of one or more symbols to be decoded. In a preferred embodiment, the arithmetic decoder is configured to determine a weighted sum of state variable values, in order to obtain the combined state variable value. In a preferred embodiment, the arithmetic decoder is configured to determine a sum of rounded values ( which are obtained by rounding products of state variable values and associated weight values (^^^^^^), in order to obtain the combined state variable value (sk). In a preferred embodiment, the arithmetic decoder is configured to determine the combined state variable value skaccording to FH240412PEP-2025112831.DOCX wherein sk2are state variable values, wherein N is a number of state variable values considered, wherein ⌊ . ⌋ is a floor operator, wherein dkiare weighting values associated with the state variable values (for example, weighting factors that control the influence of the individual state variable values onto the combined state variable value) (wherein dki are preferably integer-valued potencies of von 2, and wherein a ratio between two different dki is preferably an integer-valued potency of 2)[wherein a ratio between two different dkiis preferably larger than or equal to 8). In a preferred embodiment, the arithmetic decoder is configured to change the state variable value into a first direction (e.g. to become more positive) if a decoded symbol takes a first value (e.g. “1”), and to change the state variable value into a second direction (e.g. to become more negative) if a decoded symbol takes a second value (e.g. “0”) which is different from the first value (for example, such that the state variable value can take positive and negative values), and wherein the arithmetic decoder is configured to determine an entry of the lookup-table to be evaluated in dependence on an absolute value (skif ski>0, - skotherwise) of the combined state variable value (e.g in dependence on a scaled and rounded version of an absolute value of the combined state variable value). In a preferred embodiment, the arithmetic decoder is configured to set a probability value(pk) to a value provided by the lookup table (e.g. to ^^^^^^2[⌊ ^^^^ ∙ ^^^^ ⌋] ) if the combined statevariable value takes a first sign (e.g. a positive sign), and wherein the arithmetic decoder is configured to set the probability value (pk) to a value obtained by subtracting a valueprovided by the lookup table (e.g. to ^^^^^^2[⌊− ^^^^ ∙ ^^^^ ⌋] ) from a predetermined value (e.g.1) if the combined state variable value takes a second sign (e.g. a negative sign). In a preferred embodiment, the arithmetic decoder is configured to determine a combined probability value pkaccording to wherein LUT2 is a lookup-table containing probability values; wherein ⌊ . ⌋ is a floor operator; wherein skis a combined variable value; and wherein akis a weighting value associated with the combined state variable value (for example, a weighting value that adapts a number range of the i-th state variable value to a number of entries of the lookup-table). FH240412PEP-2025112831.DOCX In a preferred embodiment, the arithmetic decoder is configured to determine a combined probability value pkaccording to wherein LUT2 is a lookup-table containing probability values; wherein ⌊ . ⌋ is a floor operator; wherein skis a combined variable value; and wherein akis a weighting value associated with the combined state variable value (for example, a weighting value that adapts a number range of the i-th state variable value to a number of entries of the lookup-table). In a preferred embodiment, the arithmetic decoder is configured to map the combined state variable value, or the scaled and / or rounded version ( ⌊sk* ak⌋ ) thereof, onto a subinterval width value (R*pk) using a two-dimensional look-up table, entries of which are addressed in dependence on the combined state variable value (e.g. to determine a first lookup table entry coordinate) and in dependence on a coding interval size information (e.g. R) describing a size of a coding interval of the arithmetic decoding before a decoding of a symbol (e.g. to determine a second lookup table entry coordinate). In a preferred embodiment of the arithmetic decoder, the two-dimensional look-up table isrepresentable as a dyadic product between a first one-dimensional vector (^^^^^^4[… ];forming a one-dimensional look-up table) entries of which comprise probability values for different value intervals of a value domain for the combined state variable value, or thescaled and / or rounded version ( ⌊sk* ak ⌋; ⌊|^^^^| ∙ ^^^^⌋) thereof, and a second one-dimensionalvector (^^^^2(^^)) entries of which comprise quantization levels for the coding interval size information. In a preferred embodiment of the arithmetic decoder, elements of the two-dimensional lookup-table (RangTabLPS) are defined on the basis of a base lookup table (Base TabLPS), wherein a first group (or block; e.g. an “upper half”) of the elements of the two-dimensional lookup-table are identical to elements of the base lookup-table or are rounded versions of elements of the base lookup table, and wherein a second group, (or block; e.g. a “lower half”) of the elements of the two-dimensional lookup-table are scaled and rounded versions of elements of the base lookup-table. FH240412PEP-2025112831.DOCX In a preferred embodiment of the arithmetic decoder, the second group of elements of the two-dimensional lookup-table are right-shifted versions of elements of the base-lookup table. In a preferred embodiment of the arithmetic decoder, a probability index (Qp2(pLPS) or i) determines whether an element of the first group of elements of the two-dimensional lookup table or an element of a second group of elements of the two-dimensional lookup table is evaluated, wherein a first range (for example, between 0 and µ-1) of probability indices (which are, for example, obtained by quantizing a probability value, e.g. pLPS) is associated with elements of the first group of elements, and wherein a second range (for example, larger than or equal to µ) of probability indices (which are, for example, obtained by quantizing a probability value, e.g. pLPS, e.g. using a quantization function Qp2(.)) is associated with elements of the second group of elements. In a preferred embodiment of the arithmetic decoder, a division residual (i%µ) of a division between the probability index (i) and a first size value (e.g. µ; wherein the size value, for example, describes an extension of the base lookup table in a first direction) and an interval size index (which may, for example, be obtained on the basis on an interval size information R, for example using a quantization operation Qr2(.); for example, j) determine which element of the base lookup table is used to obtain the element of two-dimensional lookup table. In a preferred embodiment, the arithmetic decoder is configured to obtain an element of the two-dimensional lookup-table (RangTabLPS) according to RangeTabLPS[i][j]=Scal(BaseTabLPS[i%µ][j) , ⌊i / µ⌋) wherein BaseTabLPS is a base lookup table of dimension µ x λ; wherein i is a table index associated with a probability information; wherein j is a table index associated with an interval size information (e.g. describing a current coding interval size); wherein % is a division residual operation; wherein / is a division operation; wherein Scal (x,y) is a scaling function (for example, defined as Scal (x,y)= ⌊x*a-by⌋, wherein ⌊. ⌋ is a floor operation, wherein a is preferably a constant larger than or equal to 2, and wherein b is preferably a constant larger than or equal to 1, and wherein the scaling function is preferably implemented using a shift-to-the -right bit shift operation, wherein y determines whether and by how many bits a shift-to-the-right of x is performed). FH240412PEP-2025112831.DOCX In a preferred embodiment of the arithmetic decoder, elements of the two-dimensional lookup-table (RangTabLPS) are defined on the basis of a probability table (probTabLPS), wherein the probability table describes interval sizes for a set of a plurality of probability values (for example, represented by indices i) and for a given (reference) coding interval size, and wherein elements of the two-dimensional lookup-table for a probability value which is not in the set of a plurality of probability values and / or for a coding interval size which is different from the given coding interval size are derived from the probability table using a scaling. In a preferred embodiment of the arithmetic decoder, elements of the two-dimensional lookup-table are obtained using a (multiplicative) first scaling of a selected element (probTabLPS[i%µ]) of the probability table in dependence on the coding interval size (R), and using a second scaling of a result of the first scaling in dependence on whether an element associated with a current probability value (designated by index i) is included in the set of probability values or not (e.g. in dependence on whether the current probability value lies within a range of probability values covered by the probability table or not). In a preferred embodiment of the arithmetic decoder, a division residual (i%µ) of a division between a probability index (e.g. i; e.g. representing the current probability value) and a first size value (e.g. µ; wherein the size value, for example, describes an extension of the probability table) determines which element of the probability table is scaled in the first scaling; and / or wherein an integer division result (⌊i / µ⌋) of a division between the probability index (i) and the first size value determines a scaling factor (2-⌊ i / µ ⌋) used in the second scaling; and / or wherein the coding interval size determines a multiplicative scaling factor (Qr2(R)) of the first scaling. In a preferred embodiment, the arithmetic decoder is configured to obtain an element ^^^^^^^^^^^^^^^^^^^^^^[^^][^^] of the two-dimensional lookup-table according to ^^^^^^^^^^^^^^^^^^^^^^[^^][^^] = ^^^^^^^^(⌊^^^^^^^^^^^^^^^^^^^^[^^ % ^^] ∙ ^^^^2(^^)⌋, ⌊^^ / ^^⌋)wherein i is a table index associated with a probability information; wherein j is a table index associated with an interval size information; wherein % is a division residual operation; wherein / is a division operation; wherein probTabLPS[] is the probability table; wherein µ is a number of elements of the probability table (wherein a range of values of I is typically FH240412PEP-2025112831.DOCX larger than µ); wherein R is an interval size (or a current coding interval size); wherein Qr2(R) is a scaling factor which is dependent on R; wherein Scal (x,y) is a scaling function (for example, defined as Scal (x,y)= ⌊x*a-by⌋, wherein ⌊. ⌋ is a floor operation, wherein a is preferably a constant larger than or equal to 2, and wherein b is preferably a constant larger than or equal to 1, and wherein the scaling function is preferably implemented using a shift- to-the -right bit shift operation, wherein y determines whether and by how many bits a shift- to-the-right of x is performed). In a preferred embodiment of the arithmetic decoder, elements of the two-dimensional lookup-table are obtained using a (multiplicative) first scaling of a selected element (probTabLPS[i%µ]) of the probability table in dependence on whether an element associated with a current probability value (designated by index i) is included in the set of probability values or not (e.g. in dependence on whether the current probability value lies within a range of probability values covered by the probability table or not) and using a second scaling of a result of the first scaling in dependence on the coding interval size (R). In a preferred embodiment of the arithmetic decoder, a division residual ( ⌊i%µ⌋ ) of a division between a probability index (e.g. i; e.g. representing the current probability value) and a first size value (e.g. µ; wherein the size value, for example, describes an extension of the probability table) determines which element of the probability table is scaled in the first scaling; and / or wherein an integer division result ( ⌊i / µ⌋ ) of a division between the probability index (i) and the first size value determines a scaling factor (2-⌊ i / µ ⌋) used in the first scaling; and / or wherein the coding interval size (R) determines a multiplicative scaling factor (Qr2(R)) of the second scaling. In a preferred embodiment, the arithmetic decoder is configured to obtain an element ^^^^^^^^^^^^^^^^^^^^^^[^^][^^] of the two-dimensional lookup-table according to ^^^^^^^^^^^^^^^^^^^^^^[^^][^^] = ⌊^^^^^^^^(^^^^^^^^^^^^^^^^^^^^[^^ % ^^], ⌊^^ / ^^⌋) ∙ ^^^^2(^^)⌋wherein i is a table index associated with a probability information; wherein j is a table index associated with an interval size information; wherein % is a division residual operation; wherein / is a division operation (e.g. providing an integer result); wherein probTabLPS[] is the probability table; wherein µ is a number of elements of the probability table (wherein a range of values of I is typically larger than µ); wherein R is an interval size; wherein Qr2(R) FH240412PEP-2025112831.DOCX is a scaling factor which is dependent on R; wherein Scal (x,y) is a scaling function (for example, defined as Scal (x,y)= ⌊x*a-by⌋, wherein ⌊. ⌋ is a floor operation, wherein a is preferably a constant larger than or equal to 2, and wherein b is preferably a constant larger than or equal to 1, and wherein the scaling function is preferably implemented using a shift- to-the -right bit shift operation, wherein y determines whether and by how many bits a shift- to-the-right of x is performed). In a preferred embodiment, the arithmetic decoder is configured to compute from the combined state variable value, or the scaled and / or rounded version ( ⌊sk* ak⌋ ) thereof, a subinterval width value (R*pk) by mapping the combined state variable value (sk), or a scaledand / or rounded version thereof ( ⌊sk* ak ⌋; ⌊|^^^^| ∙ ^^^^⌋) using a one-dimensional look-up table(LUT4) entries of which comprise probability values for different value intervals of a value domain for the combined state variable value, or the scaled and / or rounded version ( ⌊sk* ak⌋; ⌊|^^^^| ∙ ^^^^⌋) thereof, onto a combined probability value, and quantizing a coding intervalsize information (e.g. R) describing a size of a coding interval of the arithmetic encoding before an encoding of a symbol onto a quantization level; determine a product (either by look-up of precomputed products, or by multiplication) between the combined probability value and the quantization level. In a preferred embodiment, the arithmetic decoder is configured to perform the quantizing the coding interval size information by applying a logical right shift onto the coding interval size information. In a preferred embodiment, the arithmetic decoder is configured to perform the quantizingthe coding interval size information ^^ by ^^^^2(^^) = (⌊^^ ∙ 2−^^⌋ + ^^) ∙ 2−^^, where ^^, ^^ and ^^are parameters. In a preferred embodiment of the arithmetic decoder, the entries of the one-dimensional look-up table monotonically decrease at an increase of the combined state variable value, or the scaled and / or rounded version ( ⌊sk* ak⌋ ) thereof. In a preferred embodiment of the arithmetic decoder, different value intervals of the value domain for the combined state variable value, or the scaled and / or rounded version ( ⌊sk* ak⌋ ) thereof, are equally sized. FH240412PEP-2025112831.DOCX In a preferred embodiment of the arithmetic decoder, the entries of the one-dimensional look-up table monotonically decrease with decreasing rate at an increase of the combined state variable value, or the scaled and / or rounded version ( ⌊sk* ak⌋ ) thereof. In a preferred embodiment of the arithmetic decoder, the lookup-table defines (for example, within a tolerance of + / -10% or + / -20%) an exponential decay (e.g. down from 0.5). In a preferred embodiment, the arithmetic decoder is configured to update the plurality of variable state values ^^^^^^according to wherein z is a predetermined (constant) offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^ are one or more weighting values, wherein A is^^[^^ + ^̂^] = ^^^^^^^^^^^^ +∑^̂^ ^^=1 max(0, ^̂^^^ − ^̂^) <<^̂^^^or deviates therefrom merely for one or more extreme values of its argument by zero setting or magnitude reduction to avoid the updated ^^^^^^leaving a predetermined value range, (e.g. consider that ^^^^^^has a value domain larger than ^^^^^^∙ ^^^^^^ ^^^^; that is, ^^^^^^is quasi quantized onto ^^^^ ∙ ^^^^^^; for extreme values of ^^^^ ∙ ^^^^^^, ^^^^^^may be modified by an unamended A according to above formula to leave its value domain; to avoid this, the entries corresponding to these extreme values might be reduced or zeroed); where ^^^^^^^^^^^^, ^̂^, ^̂^^^, and ^̂^^^are predetermined parameters (examples are set out above).In a preferred embodiment, the arithmetic decoder is configured to derive ^^[^^ + by table look-up or computationally. An embodiment according to the invention creates an arithmetic decoder for decoding a plurality of symbols having symbol values (e.g. binary values), wherein the arithmetic decoder is configured to determine one or more state variable values (s1k, s2k), which represent statistics of a plurality of previously decoded symbol values (e.g. a sequence of binary values 0 and 1) (for example, an estimate of a probabilities that one or more symbols to be decoded comprises certain symbol values) (for example, in the case that a plurality of state variable values are determined, statistics with different adaptation time constants), and wherein the arithmetic decoder is configured to derive an interval size information (pk, R*pk) for an arithmetic decoding of one or more symbol values to be decoded on the basis FH240412PEP-2025112831.DOCX of the one or more state variable values (sik) (which are, for example, associated with a given context mode, indicated by index k), which represent statistics of a plurality of previously decoded symbol values (e.g. a sequence of binary values 0 and 1) (for example, in the case that a plurality of state variable values are determined, statistics with different adaptation time constants), wherein the arithmetic decoder is configured to update a first state variable value (sk1) in dependence on a decoded symbol and using a look-up table (A) (for example, after decoding the symbol to be decoded). In a preferred embodiment, the arithmetic decoder is configured to update a second state variable value (sk2) in dependence on a decoded symbol and using the look-up table (A) (for example, after decoding the symbol to be decoded). In a preferred embodiment, the arithmetic decoder is configured update the first state variable value and the second state variable values using different adaptation time constants. In a preferred embodiment, the arithmetic decoder is configured to selectively increase or decrease a previous state variable value by a value determined using the look-up table in dependence on whether a decoded symbol takes a first value or a second value which is different from the first value. In a preferred embodiment, the arithmetic decoder is configured to increase a previous state variable value by a comparatively larger value in case that the previous state variable value is negative when compared to a case that the previous state variable value is positive if a decoded symbol takes a first value; and wherein the arithmetic decoder is configured to decrease a previous state variable value by a comparatively larger value in case that the previous state variable value is positive when compared to a case that the previous state variable value is negative if a decoded symbol takes a second value which is different from the first value (which is reached, for example, by an appropriate choice of the lookup-table). In a preferred embodiment, the arithmetic decoder is configured to determine an index of an entry of the lookup table to be evaluated when updating the first state variable value in dependence on a sum of a predetermined (e.g. fixed) offset value (z) and a previously computed first state variable value ( ^^1^^), or a scaled and / or rounded version ( ⌊ ) thereof, if a decoded symbol takes a first value; and wherein the arithmetic decoder is configured to determine an index of an entry of the lookup table to be evaluated when FH240412PEP-2025112831.DOCX updating the first state variable value in dependence on a sum of a predetermined (e.g. fixed) offset value (z) and a in inversed (multiplied by -1) version ( −^^1^^) of a previously computed first state variable value, or a scaled and / or rounded version ( thereof (e.g. of the inversed version of the previously computed first state variable value), if a decoded symbol takes a second value. In a preferred embodiment, the arithmetic decoder is configured to determine an index of an entry of the lookup table to be evaluated when updating the second state variable value in dependence on a sum of a predetermined (e.g. fixed) offset value (z) and a previously computed second state variable value ( ^^2^^), or a scaled and / or rounded version ( ⌊ ^^^^2 ∙) thereof, if a decoded symbol takes a first value; and wherein the arithmetic decoder is configured to determine an index of an entry of the lookup table to be evaluated when updating the second state variable value in dependence on a sum of a predetermined (e.g. fixed) offset value (z) and a in inversed (multiplied by -1) version ( −^^2^^) of a previously computed second state variable value, or a scaled and / or rounded version ( ) thereof (e.g. of the inversed version of the previously computed second state variable value), if a decoded symbol takes a second value. In a preferred embodiment, the arithmetic decoder is configured to apply a first scaling value (mk1), to scale the previously computed first state variable value (sk1), when determining an index of an entry of the lookup table to be evaluated when updating the first state variable value, and wherein the arithmetic decoder is configured to apply a second scaling value (mk2), to scale the previously computed second state variable value (sk2), when determining an index of an entry of the lookup table to be evaluated when updating the second state variable value, wherein the first scaling value is different from the second scaling value (and wherein the first and the second scaling values are preferably integer potencies of 2, and wherein a ratio between the first scaling value and the second scaling value is preferably an integer potency if 2, and wherein the first scaling value and the second scaling value preferably differ by a factor of at least 8). In a preferred embodiment, the arithmetic decoder is configured to scale a value returned by an evaluation of the lookup table using a first scaling value (e.g. nk1) when updating the first state variable value, FH240412PEP-2025112831.DOCX wherein the arithmetic decoder is configured to scale a value returned by an evaluation of the lookup table using a second scaling value (e.g. nk2) when updating the second state variable value, wherein the first scaling value is different from the second scaling value. In a preferred embodiment, the arithmetic decoder is configured to determine one or more updated state variable values ^^^^^^according to wherein A is a lookup table (for example, comprising integer values), wherein z is a predetermined (constant) offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^are one or more weighting values. In a preferred embodiment, the arithmetic decoder is configured to determine one or more updated state variable values ^^^^^^according to wherein A is a lookup table (for example, comprising integer values), wherein z is a predetermined (constant) offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^are one or more weighting values. In a preferred embodiment, the arithmetic decoder is configured to determine one or more updated state variable values ^^^^^^according to wherein A is a lookup table (for example, comprising integer values), wherein z is a predetermined (constant) offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^are one or more weighting values. FH240412PEP-2025112831.DOCX In a preferred embodiment, the arithmetic decoder is configured to determine one or more updated state variable values ^^^^^^according to wherein A is a lookup table (for example, comprising integer values), wherein z is a predetermined (constant) offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^are one or more weighting values. In a preferred embodiment of the arithmetic decoder, the entries of A decrease monotonically with increasing lookup table index.In a preferred embodiment of the arithmetic decoder, A is ^^[^^ + ^̂^] = ^^^^^^^^^^^^ +∑^̂^ ^^=1 max(0, ^̂^^^ − ^̂^) <<^̂^^^or deviates therefrom merely for one or more extreme values of its argument by zero setting or magnitude reduction to avoid the updated ^^^^^^leaving a predetermined value range, (e.g. consider that ^^^^^^has a value domain larger than ^^^^^^∙ ^^^^^^; that is, ^^^^^^is quasi quantized onto for extreme values of may be modified by an unamended A according to above formula to leave its value domain; to avoid this, the entries corresponding to these extreme values might be reduced or zeroed); where ^^^^^^^^^^^^, ^̂^, ^̂^^^, and ^̂^^^are predetermined parameters (examples are set out above). In a preferred embodiment of the arithmetic decoder, a last entry of the lookup table (which is addressed when the first state variable value reaches a predetermined range of values which extends up to a maximum allowable value, or when the first state variable value exceeds a predetermined threshold value) is equal to zero. In a preferred embodiment, the arithmetic decoder is configured to apply a clipping operation to the updated state variable values, to keep the updated and clipped state variable values within a predetermined range of values. In a preferred embodiment, the arithmetic decoder is configured to apply a clipping operation according to FH240412PEP-2025112831.DOCX ^^^^^^ = ^^^^^^(^^^^^^(^^ ^^^^ , ℎ ^^^^ ), ^^^^^^) to the updated state variable values, wherein ^^^^^^is a maximum allowed value for ^^^^^^, and wherein ℎ^^^^is a minimum allowed value for ^^^^^^. In a preferred embodiment, the arithmetic decoder is configured to apply different scaling values for different context models (for example, such that at least one of the scaling values differs between two different context models). In a preferred embodiment, the arithmetic decoder is configured to obtain the interval size information as defined in one of the above embodiments. An embodiment according to the invention creates an arithmetic decoder for decoding a plurality of symbols having symbol values (e.g. binary values), wherein the arithmetic decoder is configured to determine one state variable value (sk), which represent a statistic of a plurality of previously decoded symbol values, and wherein the arithmetic decoder is configured to compute from the combined state variable value, or the scaled and / or rounded version ( ⌊sk* ak⌋ ) thereof, a subinterval width value (^^^^^^^^) for an arithmetic decoding of a symbol value to be decoded by mapping the one state variable value (sk), or a scaled and / orrounded version thereof ( ⌊sk* ak ⌋; ⌊|^^^^| ∙ ^^^^⌋) using a one-dimensional look-up table(^^^^^^^^^^^^^^^^^^^^[^^^^2(… )]) entries of which comprise probability values for different valueintervals of a value domain for the combined state variable value, or the scaled and / orrounded version ( ⌊sk* ak ⌋; ⌊|^^^^| ∙ ^^^^⌋) thereof, onto a combined probability value, andquantizing a coding interval size information (e.g. R) describing a size of a coding interval of the arithmetic encoding before the arithmetic decoding of the symbol value to be encoded onto a quantization level (^^^^2(^^)); determine a product (either by look-up of precomputed products, or by multiplication) between the probability value and the quantization level, wherein the arithmetic decoder is configured to perform a state variable value update in dependence on the symbol to be decoded (actually decoded). In a preferred embodiment, the arithmetic decoder is configured to derive as the one state variable value (sk) a combined state variable value (which may, for example, be a weighted sum of state variable values) one the basis of a plurality of state variable values (sik) (e.g. a sequence of binary values 0 and 1) (for example, in the case of a plurality of state variable values, statistics with different adaptation time constants), which represent statistics of the FH240412PEP-2025112831.DOCX plurality of previously decoded symbol values (e.g. a sequence of binary values 0 and 1) with different adaptation time constants. In a preferred embodiment, the arithmetic decoder is configured to determine a weighted sum of state variable values, in order to obtain the combined state variable value. In a preferred embodiment, the arithmetic decoder is configured to determine a sum of rounded values ( ∙ ^^^^^^⌋), which are obtained by rounding products of state variable values and associated weight values in order to obtain the combined state variable value (sk). In a preferred embodiment, the arithmetic decoder is configured to determine the combined state variable value skaccording to wherein sk2 are state variable values, wherein N is a number of state variable values considered, wherein ⌊ . ⌋ is a floor operator, wherein dki are weighting values associated with the state variable values (for example, weighting factors that control the influence of the individual state variable values onto the combined state variable value) (wherein dki are preferably integer-valued potencies of von 2, and wherein a ratio between two different dki is preferably an integer-valued potency of 2)[wherein a ratio between two different dki is preferably larger than or equal to 8). In a preferred embodiment, he arithmetic decoder is configured to, in performing the state variable value update, update the plurality of state variable values ^^^^^^according to wherein z is a predetermined (constant) offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^ are one or more weighting values, wherein A is ^^[^^ + ^̂^] = ^^^^^^^^^^^^ + or deviates therefrom merely for one or more extreme values of its argument by zero setting or magnitude reduction to avoid the updated ^^^^^^leaving a FH240412PEP-2025112831.DOCX predetermined value range, (e.g. consider that ^^^^^^has a value domain larger than ^^^^^^∙ ^^^^^^; that is, ^^^^^^is quasi quantized onto ^^^^^^ ∙ ^^^^^^; for extreme values of ^^^^^^ ∙ ^^^^^^, ^^^^^^may be modified by an unamended A according to above formula to leave its value domain; to avoid this, the entries corresponding to these extreme values might be reduced or zeroed); where ^^^^^^^^^^^^, ^̂^, ^̂^^^, and ^̂^^^are predetermined parameters (examples are set out above).In a preferred embodiment, the arithmetic decoder is configured to derive ^^[^^ + by table look-up or computationally. In a preferred embodiment, the arithmetic decoder is configured to determine one or more updated state variable values ^^^^^^according to wherein A is a lookup table (for example, comprising integer values), wherein z is a predetermined (constant) offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^are one or more weighting values. In a preferred embodiment, the arithmetic decoder is configured to determine one or more updated state variable values ^^^^^^according to wherein A is a lookup table (for example, comprising integer values), wherein z is a predetermined (constant) offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^are one or more weighting values. In a preferred embodiment, the arithmetic decoder is configured to determine one or more updated state variable values ^^^^^^according to FH240412PEP-2025112831.DOCX wherein A is a lookup table (for example, comprising integer values), wherein z is a predetermined (constant) offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^are one or more weighting values. In a preferred embodiment, the arithmetic decoder is configured to perform the quantizing the coding interval size information by applying a logical right shift onto the coding interval size information. In a preferred embodiment, the arithmetic decoder is configured to perform the quantizingthe coding interval size information ^^ by ^^^^2(^^) = (⌊^^ ∙ 2−^^⌋ + ^^) ∙ 2−^^, where ^^, ^^ and ^^are parameters. In a preferred embodiment of the arithmetic decoder, the entries of the one-dimensional look-up table monotonically decrease at an increase of the one state variable value, or the scaled and / or rounded version ( ⌊sk* ak⌋ ) thereof. In a preferred embodiment of the arithmetic decoder, different value intervals of the value domain for the one state variable value, or the scaled and / or rounded version ( ⌊sk* ak⌋ ) thereof, are equally sized. In a preferred embodiment of the arithmetic decoder, the entries of the one-dimensional look-up table monotonically decrease with decreasing rate at an increase of the one state variable value, or the scaled and / or rounded version ( ⌊sk* ak⌋ ) thereof. An embodiment according to the invention creates a video encoder, wherein the video encoder is configured to encode a plurality of video frames, wherein the video encoder comprises an arithmetic encoder for providing an encoded binary sequence on the basis of a sequence of binary values representing a video content, according to one of the above embodiments. It should be noted that the arithmetic encoder discussed herein is well-suited for usage within a video encoder. In this case, the symbols to be encoded and / or the previously encoded symbols may be symbols of a video bit stream. For example, the symbols to be encoded and / or the previously encoded symbols may represent bits of a side information or control information and / or bits of encoded transform coefficients representing a video content. In other words, the symbols to be encoded and / or the previously encoded symbols FH240412PEP-2025112831.DOCX may represent any of the information which is included into the bit stream for representing a video content. However, it should be noted that the state variable values may be determined individually for different “contexts”, i.e., for different types of information. For example, only the bits associated with a given type of information (for example, a specific type of side information) may contribute to a given state variable value or to a given set of state variable values which is used to obtain a given combined state variable value. Thus, the interval size information may also be derived individually for different contexts, i.e., for the encoding of symbol values which are associated with different types of information (e.g., side information). An embodiment according to the invention creates a video decoder, wherein the video decoder is configured to decode a plurality of video frames, wherein the video decoder comprises an arithmetic decoder (120;220) for providing a decoded binary sequence (for example, on the basis of decoded symbol values) on the basis of an encoded representation (211) of the binary sequence, according to one of the above embodiments. The video decoder is based on the same considerations as the video encoder. Accordingly, the above explanations also apply, wherein encoded symbols or symbols to be encoded correspond to decoded symbols. Moreover, it should be noted that further embodiments according to the invention create respective methods and computer programs. An embodiment according to the invention creates a method for encoding a plurality of symbols having symbol values (e.g. binary values), wherein the method comprises deriving an interval size information (pk, R*pk) for an arithmetic encoding of one or more symbol values to be encoded on the basis of a plurality of state variable values (sik) (which are, for example, associated with a given context mode, indicated by index k), which represent statistics of a plurality of previously encoded symbol values (e.g. a sequence of binary values 0 and 1) with different adaptation time constants, wherein the method comprises mapping a first state variable value (sk1), or a scaled and / or rounded version ( ⌊sk1* ak1 ⌋ ) thereof, using a lookup-table (LUT1) and mapping a second state variable value (sk2), or a scaled and / or rounded version ( ⌊sk2* ak2⌋ ) thereof using the lookup-table (LUT1), in order to obtain the interval size information (e.g. pkor R*pk) describing an interval size for the arithmetic encoding of one or more symbols to be encoded. FH240412PEP-2025112831.DOCX An embodiment according to the invention creates a method for encoding a plurality of symbols having symbol values (e.g. binary values), wherein the method comprises deriving an interval size information (pk, R*pk) for an arithmetic encoding of one or more symbol values to be encoded on the basis of a plurality of state variable values (sik) (which are, for example, associated with a given context mode, indicated by index k), which represent statistics of a plurality of previously encoded symbol values (e.g. a sequence of binary values 0 and 1) with different adaptation time constants, wherein the method comprises deriving a combined state variable value (sk) (which may, for example, be a weighted sum of state variable values) one the basis of the plurality of (individual) state variable values (sik), and wherein the method comprises mapping the combined state variable value (sk), or a scaled and / or rounded version thereof ( ⌊sk2* ak2⌋ ) using a look-up table, in order to obtain the interval size information (e.g. pkor R*pk) describing an interval size for the arithmetic encoding of one or more symbols to be encoded. An embodiment according to the invention creates a method for encoding a plurality of symbols having symbol values (e.g. binary values), wherein the method comprises determining one or more state variable values (s1k, s2k), which represent statistics of a plurality of previously encoded symbol values (e.g. a sequence of binary values 0 and 1) (for example, in the case of a plurality of state variable values, statistics with different adaptation time constants), and wherein the method comprises deriving an interval size information (pk, R*pk) for an arithmetic encoding of one or more symbol values to be encoded on the basis of the one or more state variable values (sik) (which are, for example, associated with a given context mode, indicated by index k), which represent statistics of a plurality of previously encoded symbol values (e.g. a sequence of binary values 0 and 1) (for example, in the case of a plurality of state variable values, statistics with different adaptation time constants), wherein the method comprises updating a first state variable value (sk1) in dependence on a symbol to be encoded and using a look-up table (A) (for example, after encoding the symbol to be encoded). An embodiment according to the invention creates a method for decoding a plurality of symbols having symbol values (e.g. binary values), wherein the method comprises deriving an interval size information (pk, R*pk) for an arithmetic decoding of one or more symbol values to be decoded on the basis of a plurality of state variable values (sik) (which are, for example, associated with a given context model, indicated by index k), which represent statistics of a plurality of previously decoded symbol values (e.g. a sequence of binary values 0 and 1) (for example, an estimate of a probabilities that one or more symbols to be FH240412PEP-2025112831.DOCX decoded comprises certain symbol values) ) with different adaptation time constants, wherein the method comprises mapping a first state variable value (sk1), or a scaled and / or rounded version ( ⌊sk1* ak1⌋ ) thereof, using a lookup-table (LUT1) and mapping a second state variable value (sk2), or a scaled and / or rounded version ( ⌊sk2* ak2⌋ ) thereof using the lookup-table (LUT1), in order to obtain the interval size information (e.g. pk or R*pk) describing an interval size for the arithmetic decoding of one or more symbols to be decoded. An embodiment according to the invention creates a method for decoding a plurality of symbols having symbol values (e.g. binary values), wherein the method comprises deriving an interval size information (pk, R*pk) for an arithmetic decoding of one or more symbol values to be decoded on the basis of a plurality of state variable values (sik) (which are, for example, associated with a given context mode, indicated by index k), which represent statistics of a plurality of previously decoded symbol values (e.g. a sequence of binary values 0 and 1) (for example, an estimate of a probabilities that one or more symbols to be decoded comprises certain symbol values) with different adaptation time constants, wherein the method comprises deriving a combined state variable value (sk) (which may, for example, be a weighted sum of state variable values) one the basis of the plurality of (individual) state variable values (sik), and wherein the method comprises mapping the combined state variable value (sk), or a scaled and / or rounded version thereof ( ⌊sk2* ak2⌋ ) using a look-up table, in order to obtain the interval size information (e.g. pk or R*pk) describing an interval size for the arithmetic decoding of one or more symbols to be decoded. An embodiment according to the invention creates a method for decoding a plurality of symbols having symbol values (e.g. binary values), wherein the method comprises determining one or more state variable values (s1k, s2k), which represent statistics of a plurality of previously decoded symbol values (e.g. a sequence of binary values 0 and 1) (for example, an estimate of a probabilities that one or more symbols to be decoded comprises certain symbol values) (for example, in the case that a plurality of state variable values are determined, statistics with different adaptation time constants), and wherein the method comprises deriving an interval size information (pk, R*pk) for an arithmetic decoding of one or more symbol values to be decoded on the basis of the one or more state variable values (sik) (which are, for example, associated with a given context mode, indicated by index k), which represent statistics of a plurality of previously decoded symbol values (e.g. a sequence of binary values 0 and 1) (for example, in the case that a plurality of state FH240412PEP-2025112831.DOCX variable values are determined, statistics with different adaptation time constants), wherein the method comprises updating a first state variable value (sk1) in dependence on a decoded symbol and using a look-up table (A). Embodiments according to the invention create Methods performed by encoder and decoder according to one of the above embodiments. An embodiment according to the invention creates a computer program for performing the method according to one of the above embodiments when the computer program runs on a computer. An embodiment according to the invention creates a method for encoding a plurality of symbols having symbol values (e.g. binary values), wherein the method comprises deriving an interval size value (RLPS) for an arithmetic encoding of one or more symbol values to be encoded on the basis of one or more state variable values (sik) (which are, for example, associated with a given context mode, indicated by index k), which represent statistics of a plurality of previously encoded symbol values (e.g. a sequence of binary values 0 and 1) (e.g. with different adaptation time constants); wherein the method comprises determining the interval size value (RLPS) using a base lookup table (Base TabLPS), (a dimension of which in terms of probability indices is smaller than a number of possible probability indices i), wherein the method comprises determining the interval size value (RLPS) such that a determined interval size value is identical to an element of the base lookup table or is a rounded version of an element of the base lookup table if a probability index (i), which is obtained on the basis of the one or more state variable values (for example, as i=Qp(pLPS)), is within a first range (e.g. smaller than µ), and such that a determined interval size value is obtained using a scaling and rounding of an element of the base lookup table if the probability index is within a second range (e.g. larger than or equal to µ); and wherein the method comprises performing the arithmetic encoding of one or more symbols using the interval size value (RLPS). An embodiment according to the invention creates a method for encoding a plurality of symbols having symbol values (e.g. binary values), wherein the method comprises deriving an interval size value (RLPS) for an arithmetic encoding of one or more symbol values to be encoded on the basis of one or more state variable values (sik) (which are, for example, associated with a given context mode, indicated by index k), which represent statistics of a plurality of previously encoded symbol values (e.g. a sequence of binary values 0 and 1) FH240412PEP-2025112831.DOCX (e.g. with different adaptation time constants); wherein the method comprises determining the interval size value (RLPS) using a probability table (Prob TabLPS), (a dimension of which in terms of probability indices is smaller than a number of possible probability indices i) on the basis of a (current) probability value derived from the one or more state variable values and on the basis of a (current) coding interval size (R), wherein the probability table describes interval sizes (interval size values) for a set of a plurality of probability values (for example, for probability indices between 0 and µ-1) and for a (single) given (reference) coding interval size, and wherein the method comprises scaling an element of the probability table (Prob_TabLPS) (for example, an element selected in dependence on the current probability value), to obtain the interval size value[RLPS) if a current probability value is not in the set of a plurality of probability values (for example, is a probability index associated with the current probability value is larger than or equal to µ) and / or if a current coding interval size (R) is different from the given (reference) coding interval size; and wherein the method comprises performing the arithmetic encoding of one or more symbols using the interval size value (RLPS). An embodiment according to the invention creates a method for decoding a plurality of symbols having symbol values (e.g. binary values), wherein the method comprises deriving an interval size value (RLPS) for an arithmetic decoding of one or more symbol values to be decoded on the basis of one or more state variable values (sik) (which are, for example, associated with a given context mode, indicated by index k), which represent statistics of a plurality of previously decoded symbol values (e.g. a sequence of binary values 0 and 1) (e.g. with different adaptation time constants); wherein the method comprises determining the interval size value (RLPS) using a base lookup table (Base TabLPS), (a dimension of which in terms of probability indices is smaller than a number of possible probability indices i), wherein the method comprises determining the interval size value (RLPS) such that a determined interval size value is identical to an element of the base lookup table or is a rounded version of an element of the base lookup table if a probability index (i), which is obtained on the basis of the one or more state variable values (for example, as i=Qp(pLPS)), is within a first range (e.g. smaller than µ), and such that a determined interval size value is obtained using a scaling and rounding of an element of the base lookup table if the probability index is within a second range (e.g. larger than or equal to µ); and wherein the method comprises performing the arithmetic decoding of one or more symbols using the interval size value (RLPS). FH240412PEP-2025112831.DOCX An embodiment according to the invention creates a method for decoding a plurality of symbols having symbol values (e.g. binary values), wherein the method comprises deriving an interval size value (RLPS) for an arithmetic decoding of one or more symbol values to be decoded on the basis of one or more state variable values (sik) (which are, for example, associated with a given context mode, indicated by index k), which represent statistics of a plurality of previously decoded symbol values (e.g. a sequence of binary values 0 and 1) (e.g. with different adaptation time constants); wherein the method comprises determining the interval size value (RLPS) using a probability table (Prob TabLPS), (a dimension of which in terms of probability indices is smaller than a number of possible probability indices i) on the basis of a (current) probability value derived from the one or more state variable values and on the basis of a (current) coding interval size (R), wherein the probability table describes interval sizes (interval size values) for a set of a plurality of probability values (for example, for probability indices between 0 and µ-1) and for a (single) given (reference) coding interval size, and wherein the method comprises scaling an element of the probability table (Prob_TabLPS) (for example, an element selected in dependence on the current probability value), to obtain the interval size value[RLPS) if a current probability value is not in the set of a plurality of probability values (for example, is a probability index associated with the current probability value is larger than or equal to µ) and / or if a current coding interval size (R) is different from the given (reference) coding interval size; and wherein the method comprises performing the arithmetic decoding of one or more symbols using the interval size value (RLPS). An embodiment according to the invention creates a computer program for performing the method according to one of the above embodiments when the computer program runs on a computer. The above-mentioned methods are based on the same considerations as the above- discussed apparatuses. However, it should be noted that the methods can optionally be supplemented by any of the features, functionalities and the details described herein, also with respect to the apparatuses. The methods can optionally be supplemented by said features, functionalities and the details both individually and taken in combination. The same is also true for the computer programs. In the following, further embodiments according to the invention are discussed. These embodiments are structured according to a first, second and third aspect. However, this separation into aspects is to be understood merely as a help for facilitating understanding FH240412PEP-2025112831.DOCX the respective embodiments. Features, functionalities and details of an of the embodiments of the first, second or third aspect may be used in combination or as an alternative to any of the features, functionalities and details of any of the other two aspects, both individually and taken in combination. Furthermore, in the following embodiments comprising decoders and encoders are discussed. It is to be noted that features, functionalities and details disclosed in the context of a decoder are to be understood as well as corresponding features, functionalities and details of a corresponding encoder and vice versa. Furthermore, technical advantages, effects and any other explanation provided with respect to a decoder applies in a similar or corresponding manner to a corresponding encoder and vice versa. Furthermore, any of features, functionalities and details of the following embodiments according to the first, second or third aspect may be used in combination with or as an alternative to any of the features, functionalities and details of any of the other embodiments disclosed herein, both individually or taken in combination. Hence, any feature, functionality and / or detail of any of the following embodiments may be supplemented by any other feature, functionality and / or detail of any of the other embodiments disclosed herein, both individually or taken in combination. Embodiments according to a first aspect comprise an arithmetic decoder for decoding a plurality of symbols having symbol values (e.g. symbols of medical data; e.g. symbols describing EKG signals or EEG signals; e.g. symbols representing audio signals or video signals), wherein the arithmetic decoder is configured to determine one or more state variable values (e.g. s1k, s2k), which represent statistics of a plurality of previously decoded symbol values, and wherein the arithmetic decoder is configured to derive an interval size information (e.g. pk, R*pk;) for an arithmetic decoding of one or more symbol values to be decoded on the basis of one or more state variable values which represent statistics of a plurality of previously decoded symbol values (e.g. on the basis of a plurality of state variable values (e.g. sik), which represent statistics of a plurality of previously decoded symbol values with different adaptation time constants) (wherein, for example, the arithmetic decoder is configured to map the one or more state variable values, in order to obtain the interval size information describing an interval size for the arithmetic decoding of FH240412PEP-2025112831.DOCX one or more symbols to be decoded) (wherein, for example, the arithmetic decoder is configured to map a combined state variable value, or a scaled and / or rounded version thereof, using a lookup-table (e.g. LUT1 or ProbLPSmapping) in order to obtain the interval size information describing an interval size for the arithmetic decoding of one or more symbols to be decoded). Furthermore, the arithmetic decoder is configured to selectively increase an adaptation speed of one or more of the state variable values (e.g. of a single one of the one more state variable values, or of all of the one or more state variable values) (e.g. a speed at which the one or more state variable values are adapted to a probability of decoded symbol values) (e.g. of one or more of the one or more state variable values) for a predetermined number of bins following an initialization of the one or more state variable values (e.g. until a predetermined number of bins, following an initialization of the one or more state variable values were decoded); and / or the arithmetic decoder is configured to selectively reduce an adaptation speed of one or more of the state variable values (e.g. of a single one of the one more state variable values, or of all of the one or more state variable values) (e.g. a speed at which the one or more state variable values are adapted to a probability of decoded symbol values) (e.g. of one or more of the one or more state variable values) when a predetermined number of bins following an initialization of one or more state variable values has passed (e.g. has been used for an adaptation of one or more of the state variable values using a comparatively higher adaptation speed) (e.g. until a predetermined number of bins, following an initialization of the one or more state variable values were decoded); and / or the arithmetic decoder is configured to use a first, comparatively higher (e.g. faster) adaptation speed for adapting one or more of the state variable values (e.g. one or more of the one or more state variable values) to a probability (e.g. to an actual rate of occurrence) of decoded symbol values for a first group of bins following an initialization of the one or more state variable values, and to use a second, comparatively lower adaptation speed (e.g. lower that the first adaptation speed) for adapting one or more of the state variable values (e.g. one or more of the one or more state variable values) to a probability (e.g. to an actual rate of occurrence) of decoded symbol values for a second group of bins following the first group of bins (e.g. for the remaining bins following the first group of bins). Hence, embodiments may, for example, enable a fast (or at least comparatively faster) adaptation of state variable values and therefore, for example, as well of context models, for a period of time after initialization. For example, after an initialization of such a context model, for example, by initializing the one or more state variable values (which may FH240412PEP-2025112831.DOCX represent a current state of the context model) and, for example, by initializing an adaptation parameter value (e.g. which may define a characteristic of a state transition rule of the context model; e.g. a scaling value, e.g. ^^^^^^) of the context model, the adaptation parameter value (e.g. the scaling value) may be adapted, for increasing an adaptation speed of the one or more state variable values, for the predetermined number of bins following the initialization. An adaptation parameter may, for example, be a predetermined parameter, which is, for example in principle, independent from the bins which are coded (but a value of which may, for example in addition, be chosen based on characteristics of the bins which are coded (e.g. encoded or decoded)). An adaptation parameter value may hence define (or be used to define) an extent or a strength of a change of state variable values in response to a bin which is coded. Hence, given a same bin value and same one or more initial state variable values, the adapted, e.g. new, adaptation parameter value may cause a larger change of the one or more state variable values compared to a change of the one or more state variable values based on the initialization value of the adaptation parameter. It was recognized that such an increased adaptation speed right after initialization enables an improved coding efficiency as the context model can be adapted quicker to the statistics of the bins which are coded (wherein the increased adaptation speed may be effective when it is useful, e.g. for a certain (e.g. predetermined) number of bins following the initialization) Accordingly, an appropriate state of the context, which fits the coded bins, can be reached with a relatively quick adaptation rate (e.g. within a relatively short adaptation time), wherein the relatively quick adaptation rate may, for example, be used for a limited time only, after the initialization, while a relatively slower adaptation rate of the state of the context (which may, for example, prevent excessive fluctuations of the state of the context) can be used later (e.g. for coded bins having a sufficient (e.g. temporal or “logic”) distance (e.g. in terms of a bin count) from the initialization. Accordingly, a good coding result can be achieved even if the initial state value (which may, for example, be set in the initialization) does not fit the statistics of the coded symbols well. Alternatively or in addition, the initialization value of the adaptation parameter may, for example, already enable a high adaptation rate of the state variable values. Accordingly, for example given such an initialization value, after coding the predetermined number of bins using such an adaptation parameter value, the coder (e.g. decoder or respectively FH240412PEP-2025112831.DOCX encoder) may reduce the adaptation speed, e.g. by choosing a different adaptation parameter value which enables or causes a reduced adaptation speed. Hence, again, an increased adaptation speed right after an initialization can be enabled, so that the context model can be adapted quicker to the statistics of the bins which are coded, but thereafter a slower (e.g. more fine-grained or fine-tuned) context adaptation or respectively state variable adaptation can be enabled by the slower adaptation rate. Here, it is to be noted that such a reduction in adaptation speed is not limited to an “aggressive” initialization value of the adaptation parameter (providing a large adaptation rate). The reduction in adaptation speed can also be applied to converge from a mere relatively faster context adaptation phase to a relatively slower context adaptation phase. An effect thereof, e.g. faster convergence at the beginning and a slower (e.g. more precise) adaptation to statistics of the bins thereafter, may, in principle, be the same. Furthermore, it was recognized that such a faster adaptation episode as well as a respective change to a slower adaptation episode of the state variable values or respectively of the context model may, for example, be controlled based on a simple count of coded bins. Hence, the switching may, for example, be managed based on counting whether the predetermined number of bins was already coded or respectively used for updating the state variable values. The faster and slower context adaptation phases may, for example, as well both be limited by respective bin counts, so that the fast adaptation rate is applied until a first group of bins is coded or processed and so that the slower adaptation rate is applied until a second group of bins is coded or processed. Hence, one or even both adaptation phases may, for example, have predetermined lifetimes. Thereafter, for example, a default or just any different suitable adaptation rate may be applied (or the second adaptation rate and respective adaptation parameter values may be maintained), e.g. by a respective choice of an adaptation parameter value (e.g. even returning to default or initialized adaptation parameter values). Here, it is to be noted that for the sake of comprehensibility, some of the above explanations were directed to a context model adaptation using adaptation parameter values. However, embodiments are not limited to this exact approach. A decoder (or respectively encoder) according to embodiments may be configured to manipulate any means, which influence FH240412PEP-2025112831.DOCX an adaptation rate of state variable values. This may, for example, include a change of the underlying state transition rules of a respective context model. Hence, not only a parametrization of such a state transition rule may be amended, but the rule itself as well. According to embodiments of the first aspect, the arithmetic decoder is configured to selectively modify a scaling value (e.g. nik) (e.g. as an example of an adaptation parameter value or as a processed version of an adaptation parameter information, e.g. ^^^^^^^^^^^^^^^^^^^^^^, e.g. according to ^^^^^^ = which adjusts a magnitude of a change of one or more of the state variable values, which occurs in response to an decoded symbol, in dependence on a counting of bins processed since an initialization of the one or more state variable values. A scaling enables an efficient adaptation of the adaptation speed of the state variable values. According to embodiments of the first aspect, the arithmetic decoder is configured todetermine an increment value (e.g. ⌊^^[^^ + ⌊ ), by which one or more of the state variable values (e.g. ^^^^^^) are incremented in case that a symbol to be decoded takesa first symbol value (e.g. “1”), in dependence on a scaling value (^^. ^^ ^^^^^^); wherein thearithmetic decoder is configured to determine a decrement value (e.g. ⌊^^[^^ + ∙), by which one or more of the state variable values (e.g. ^^^^^^) are decremented in case that a symbol to be decoded takes a second symbol value (e.g. “0”), in dependence on the scaling value (e.g. ^^^^^^); and wherein the arithmetic decoder is configured to gradually or step-wisely reduce the scaling value in dependence on a number of bins processed since an initialization of the one or more state variable values. For example, an adaptation speed may hence be adapted gradually or step-wisely by amending the scaling value. Furthermore, a scaling of increment or decrement values enables an efficient adaptation of the adaptation speed of the state variable values. According to embodiments of the first aspect, the arithmetic decoder is configured to set thescaling value (^^. ^^ to a first value for a first plurality of bins (e.g. for 63 bins) following an initialization of the one or more state variable values (e.g. ^^^^^^), and the arithmetic decoderis configured to set the scaling value (^^. ^^ ^^^^^^) to a second value, which is smaller than the first value, for a second plurality of bins following the first plurality of bins. FH240412PEP-2025112831.DOCX Optionally, the scaling value may be constant for predefined numbers of bins which are coded, e.g. hence a first value may be used for the first plurality of bins and a second value for the second plurality of bins. This may hence keep the complexity of the adaptation speed customization low, as only few parameter changes may have to be performed. According to embodiments of the first aspect, the arithmetic decoder is configured to update a first state variable value (e.g. sk0, e.g. sk1) (e.g. of the one or more state variable values) in dependence on a symbol to be decoded and using a look-up table (A) and the arithmeticdecoder is configured to scale a table value (e.g. ) obtained using the look-up table using a scaling value (e.g. using a first scaling value, e.g. )(^^^^^^), in order to obtain an increment value by which the first state variable value is incremented or a decrement value by which the first state variable value is decremented. According to embodiments of the first aspect, the arithmetic decoder is configured to update a second state variable value (e.g. sk2) (e.g. of the one or more state variable values) in dependence on a symbol to be decoded and using a look-up table (A); wherein thearithmetic decoder is configured to scale a table value (e.g. ^^[^^ + ⌊ or ∙ ^^^^^^⌋]) obtained using the look-up table using a scaling value (e.g. using asecond scaling value) (^^. ^^ ^^^^^^), in order to obtain an increment value by which the second state variable value is incremented or a decrement value by which the second state variable value is decremented. It was recognized that that an interval size information can be obtained with particularly good reliability if lookup-table-based mappings are applied to state variable values. Furthermore, embodiments may comprise a change of adaptation speed of a plurality of state variable values, e.g. comprising an application of different scaling values to increment or decrement values depending on a number of bins coded. According to embodiments of the first aspect, the arithmetic decoder is configured update the first state variable value and the second state variable value using different adaptation time constants at least for the second group of bins. FH240412PEP-2025112831.DOCX Hence, for example, after a first context adaptation phase in which larger increments or decrements for the state variable values are to be performed, thereafter, a more fine- grained context adaptation may be desired. Therefore, individual state variables may, for example, be subject to individual transitions rules, leading to different adaptation speeds, in order to increase coding efficiency. For example, the transition rules may as well be similar or even the same but may have a different updating parametrization for the different state variables. According to embodiments of the first aspect, the arithmetic decoder is configured to selectively increase or decrease a previous state variable value (e.g. of the one or more state variable values) by a value determined using the look-up table in dependence on whether a symbol to be decoded takes a first value (e.g. “1”) or a second value (e.g. “0”) which is different from the first value. According to embodiments of the first aspect, a magnitude of the increase or decrease is dependent on a number of bins processed since an initialization of the one or more state variable values. According to embodiments of the first aspect, the arithmetic decoder is configured to increase a previous state variable value by a comparatively larger value in case that the previous state variable value is negative when compared to a case that the previous state variable value is positive if a symbol to be decoded takes a first value; and the arithmetic decoder is configured to decrease a previous state variable value by a comparatively larger value in case that the previous state variable value is positive when compared to a case that the previous state variable value is negative if a symbol to be decoded takes a second value which is different from the first value. This approach may increase an efficiency of the adaptation of the state variable values. According to embodiments of the first aspect, the arithmetic decoder is configured to determine an index of an entry of the lookup table to be evaluated when updating the first state variable value in dependence on a sum of a predetermined offset value (e.g. z) and a previously computed first state variable value (e.g. ^^1^^), or a scaled and / or rounded version (e.g. thereof, if a symbol to be decoded takes a first value; and the arithmetic decoder is configured to determine an index of an entry of the lookup table to be evaluated when updating the first state variable value in dependence on a sum of a predetermined FH240412PEP-2025112831.DOCX offset value (e.g. z) and a in inversed version (e.g. −^^1^^) of a previously computed first state variable value, or a scaled and / or rounded version (e.g. thereof, if a symbol to be decoded takes a second value. This approach may enable an efficient updating of state variable values. According to embodiments of the first aspect, the arithmetic decoder is configured to determine an index of an entry of the lookup table to be evaluated when updating the second state variable value in dependence on a sum of a predetermined offset value (z) and a previously computed second state variable value ( ^^2^^), or a scaled and / or rounded version ( ⌊ ) thereof, if a symbol to be decoded takes a first value; and the arithmetic decoder is configured to determine an index of an entry of the lookup table to be evaluated when updating the second state variable value in dependence on a sum of a predetermined offset value (z) and a in inversed version ( −^^2^^) of a previously computed second state variable value, or a scaled and / or rounded version ( ) thereof, if a symbol to be decoded takes a second value. This approach may enable an efficient updating of state variable values. According to embodiments of the first aspect, the arithmetic decoder is configured to apply a first scaling value (e.g. as an example of an adaptation parameter value, e.g. mk0, e.g. mk1), to scale the previously computed first state variable value (e.g. sk0, e.g. sk1), when determining an index of an entry of the lookup table to be evaluated when updating the first state variable value, and the arithmetic decoder is configured to apply a second scaling value (e.g. as an example of an adaptation parameter value, e.g. mk1, e.g. mk2), to scale the previously computed second state variable value (e.g. sk1, sk2), when determining an index of an entry of the lookup table to be evaluated when updating the second state variable value, wherein the first scaling value is different from the second scaling value. It was recognized that a same lookup table, for the updates of both the first and second state variable value may be used, enabling a simple but efficient updating. Furthermore, using different scalings for different state variable values for evaluation of the lookup table may allow for an improved adaptation of a respective context model to the statistics of the bins to be coded. FH240412PEP-2025112831.DOCX According to embodiments of the first aspect, the arithmetic decoder is configured to scale a value returned by an evaluation of the lookup table using a first scaling value when updating the first state variable value, wherein the arithmetic decoder is configured to scale a value returned by an evaluation of the lookup table using a second scaling value when updating the second state variable value, wherein the first scaling value is different from the second scaling value. It was recognized that a same lookup table may be used for the updates of both the first and second state variable value, enabling a simple but efficient updating. Furthermore, using a different scaling, respective results of the lookup table mapping may allow for an improved adaptation of a respective context model to the statistics of the bins to be coded. Hence, a scaling of a table index information, as well as of a table entry information may, for example, be performed individually for respective state variable value updates. According to embodiments of the first aspect, the arithmetic decoder is configured to determine one or more updated state variable values ^^^^^^according to wherein A is a lookup table, wherein z is a predetermined offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^are one or more weighting values. This approach may enable an efficient updating of state variable values. According to embodiments of the first aspect, a number of state variables (e.g. per context model) is equal to 2; wherein ^^ = {157, 143, 129, 115, 101, 87, 73, 59, 45, 35, 29, 23, 17, 13, 9, 5,4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 0};wherein z=16; wherein ^^^^^^^^^^^^^^^^^^^^is a number (e.g. a minimum number) of bits sufficient to represent state ^^^^^^(e.g. all possible values of ^^^^^^) as a signed integer in 2's complement representation; wherein ^^^^ 5−^^^^^^^^^^^^^^^^^^^^ = 2 ^^; wherein ^^^^^^^^^^^^^^^^^^^^^^is an adaptation rate FH240412PEP-2025112831.DOCX parameter associated with state variable (e.g. “hypothesis”) ^^^^^^(wherein, for example, ^^^^^^^^^^^^^^^^^^^^^^takes a first, comparatively smaller value for a first group of bins following an initialization of the one or more state variable value, and wherein, for example, ^^^^^^^^^^^^^^^^^^^^^^takes a second, comparatively larger value for a second group of bins following the first group of bins) and wherein This approach may enable an efficient updating of state variable values. According to embodiments of the first aspect, the arithmetic decoder is configured to initialize a counter with a predetermined value (e.g. countInit; e.g countinit=63) before decoding a first bin (e.g. symbol) associated with a given context model (e.g. a context model having context model index k); and the arithmetic decoder is configured to update the counter after decoding a respective bin associated with the given context model (e.g. by step-wisely decrementing the counter by one (e.g. per decoded bin) in response to a decoding of a respective bin associated with the given context model, until the counter hasreached a value of zero) (e.g. by setting ^^^^^^^^^^^^ to ^^^^^^(0, ^^^^^^^^^^^^ − 1) in response to adecoding of a respective bin associated with the given context model). It was recognized that a use of a counter enables an efficient managing of adaptation speed changes. Hence, using said counter, it can be derived efficiently, whether a predetermined number of bins was coded.According to embodiments of the first aspect, countInit=63; ^^^^^^^^^^^^^^^^^^0 = 10; ^^^^^^^^^^^^^^^^^^1 =13; ^^^^^^^^^^^^^^^^^^^^ 1, ^^^^ ^^^^^^^^^^^^ > 0 1, ^^^^ ^^^^^^^^^^^^ > 00 = {2, ^^^^ℎ^^^^^^^^^^^^. ; and ^^^^^^^^^^^^^^^^^^^^1 = {5, ^^^^ℎ^^^^^^^^^^^^. . The above setting of counter and adaptation rate changes enables a fast context adaptation after initialization and a subsequent fine-grained context adaptation thereafter. A transition after 63 coded bins was found to be particularly advantageous. According to embodiments of the first aspect, the arithmetic decoder is configured to determine one or more updated state variable values ^^^^^^according to FH240412PEP-2025112831.DOCX wherein A is a lookup table, wherein z is a predetermined offset value; wherein are one or more weighting values; wherein ^^^^^^are one or more weighting values. It was recognized that the above formula enables an efficient implementation of state variable value transitions. According to embodiments of the first aspect, the arithmetic decoder is configured to determine one or more updated state variable values ^^^^^^according to wherein A is a lookup table, wherein z is a predetermined offset value; wherein ^^^^^^are one or more weighting values and wherein ^^^^^^are one or more weighting values. It was recognized that the above formula enables another efficient implementation of state variable value transitions. According to embodiments of the first aspect, the arithmetic decoder is configured to determine one or more updated state variable values ^^^^^^according to wherein A is a lookup table, wherein z is a predetermined offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^are one or more weighting values. It was recognized that the above formula enables as well an efficient implementation of state transitions. According to embodiments of the first aspect, the entries of A decrease monotonically with increasing lookup table index. FH240412PEP-2025112831.DOCX It was recognized that such a structure of A enables an efficient adaptation of the state variable values to statistics of the bins which are coded. For example, using monotonically decreasing entries of the lookup table has shown to bring along good results for the interval size information. According to embodiments of the first aspect, A is or deviates therefrom merely for one or more extreme values of its argument by zero setting or magnitude reduction to avoid the updated ^^^^^^leaving a predetermined value range, where ^^^^^^^^^^^^, ^̂^, ^̂^^^, and ^̂^^^are predetermined parameters. It was found that the above formula enables an efficient state variable value updating, using the entries of A. According to embodiments of the first aspect, a last entry of the lookup table is equal to zero. This may, for example, allow maintaining a specific state, e.g. in case the state variable values do already represent respective statistics of bins to be coded well. For example, by using a last entry of the lookup table, which is equal to 0, it can easily be avoided that the updated state variable value exceeds a maximum value and / or a minimum value. According to embodiments of the first aspect, the arithmetic decoder is configured to apply a clipping operation to the updated state variable values, to keep the updated and clipped state variable values within a predetermined range of values. Using such a mechanism, it can easily be prevented that a state variable value exceeds the predetermined range between a minimum value and a maximum value. Accordingly, it can be ensured that the state variable value takes “reasonable” values. FH240412PEP-2025112831.DOCX According to embodiments of the first aspect, the arithmetic decoder is configured to apply a clipping operation according to ^^^^^^ = ^^^^^^(^^^^^^(^^ ^^ ^^^^ , ℎ^^ ), ^^^^^^) to the updated state variable values, wherein ^^^^^^is a maximum allowed value for ^^^^^^, and wherein ℎ^^^^is a minimum allowed value for ^^^^^^. It has been found that such a clipping operation can be implemented in an efficient manner and avoids invalid state variable values. According to embodiments of the first aspect, the arithmetic decoder is configured to apply different scaling values for different context models. Using different scaling values for different context models, the different statistic characteristics of the different context models (which may be associated with different types of information and / or types of bit stream syntax elements) can be considered. By using different scaling values for the different context models, the update procedure for the state variable values can easily be adapted to different context models without fundamentally changing the underlying algorithm. Thus, appropriate scaling values can be obtained in a very efficient manner. According to embodiments of the first aspect, the arithmetic decoder is configured to obtain the interval size information as defined in one of embodiments 119 to 155 (as discussed later). According to embodiments of the first aspect, the arithmetic decoder is configured to update a first state variable value (e.g. sk0) in dependence on a symbol to be decoded (for example, using a look-up table (e.g. A)); the arithmetic decoder is configured to derive a second state variable value (e.g. sk1) on the basis of the first state variable value for a first group of bins following an initialization of the two or more state variable values (e.g. for a predetermined number of bins following an initialization of the one or more state variable values), and the arithmetic decoder is configured to update the second state variable value (e.g. sk1) in dependence on a symbol to be decoded for a second group of bins following the first group of bins (e.g. when a predetermined number of bins following an initialization of one or more state variable values has passed); (wherein, for example, deriving the second state variable FH240412PEP-2025112831.DOCX value on the basis of the first state variable value for the first group of bins following the initialization of the two or more state variable values has the effect that adaptation speed for adapting the first state variable value and the second state variable value to a probability (e.g. to an actual rate of occurrence) of decoded symbol values is comparatively high for the first group of bins following an initialization of the state variable values, and that the adaptation of the first state variable value and of the second state variable value is highly efficient for the first group of bins following the initialization of the state variable values). For the advantages of this approach reference is made to the explanations regarding the following decoder according to the second aspect. Furthermore, a combination of the approach according to the first aspect and according to the second aspect enables to combine the advantages of the changing adaptation speeds for context adaptation with the advantages of reduced complexity by scaling one state variable value based on another. Hence, the combination of these approaches may combine advantages and mitigate drawbacks of one another. FH240412PEP-2025112831.DOCX Embodiments according to a second aspect comprise an arithmetic decoder for decoding a plurality of symbols having symbol values (e.g. symbols of medical data; e.g. symbols describing EKG signals or EEG signals; e.g. symbols representing audio signals or video signals), wherein the arithmetic decoder is configured to determine a plurality of (e.g. two or more) state variable values (e.g. s0k, s1k), which represent statistics of a plurality of previously decoded symbol values, and wherein the arithmetic decoder is configured to derive an interval size information (e.g. pk, R*pk) for an arithmetic decoding of one or more symbol values to be decoded on the basis of the two or more state variable values (e.g. sik), which represent statistics of a plurality of previously decoded symbol values, wherein the arithmetic decoder is configured to update a first state variable value (e.g. sk0) in dependence on a symbol to be decoded (for example, using a look-up table (e.g. A)); wherein the arithmetic decoder is configured to derive a second state variable value (e.g. sk1) on the basis of the first state variable value for a first group of bins following an initialization of the one or more state variable values (e.g. for a predetermined number of bins following an initialization of the one or more state variable values), and wherein the arithmetic decoder is configured to update the second state variable value (sk1) in dependence on a symbol to be decoded for a second group of bins following the first group of bins (e.g. when a predetermined number of bins following an initialization of one or more state variable values has passed). It was recognized that a coupling of an updating of state variable values (which may, for example, be related to a common context model; which may, for example, be used jointly; which may, for example, be combined or coupled; which may, for example, comprise different update speeds in a normal operation mode; and / or which may, for example, not evolve precisely in parallel in a normal operation mode) to derive an interval size information for a predetermined number of bins (e.g. the first group of bins; e.g. a special operation mode) after initialization enables improving the coding efficiency. It was recognized that this approach enables improving an initial adaptation of a respective context model to statistics of the bins to be coded (wherein a state of the context model may be represented by (e.g. at least inter alia) the first and second state variable value). After such an improved adaptation phase, an updating of the second state variable value may be performed (e.g. in a normal operation mode) based on the bins to be coded, e.g. separate from the updating of the first state variable value but, for example, using a similar update rule like for updating of the first state variable value (but with different update parameters). FH240412PEP-2025112831.DOCX For example, for the update of the first state variable value, sophisticated, e.g. even computationally expensive, but effective update mechanics may be implemented. By coupling the updating of the second state variable value to the first state variable value, the benefits of such a sophisticated update may be translated to the second state variable value, but with significantly reduced effort, e.g. by way of providing the second state variable value based on a scaling of the first state variable value, but, for example without a complex evaluation of state update rules (e.g. as done for the first state variable). Moreover, a computational complexity is reduced even if a relatively simple rule is used for the updating of the first state variable value. Also, common time constants apply for the update of the first state variable value and for the update of the second state variable value to the time period following the initialization of the state variables, which may, for example, speed up reaching a state in which the state variable values represent bin probabilities with good accuracy. For example, the first state variable may be subject to a faster adaptation rate than the second state variable value, so that upon coupling the second state variable value to the first state variable value, a faster adaptation of the second state variable value may be achieved (e.g. after initialization). Furthermore, as discussed before, such a change of adaptation modes may, for example, be controlled by a simple count of bins to be coded, hence allowing for an efficient implementation. According to embodiments of the second aspect, the arithmetic decoder is configured to scale the first state variable value, in order to derive the second state variable value from the first state variable value for a first group of bins following an initialization of the one or more state variable values (e.g. such that the second state variable value is a scaled version of the first state variable value for the first group of bins following the initialization of the one or more state variable values, e.g. such that the second state variable value follows the first state variable value in a substantially proportional manner for the first group of bins following the initialization of the one or more state variable values, and such that the second state variable value is determined independently from the first state variable value for the second group of bins). It was recognized that a scaling enables an efficient coupling of the updating of the first and second state variable values. Hence, an efficient updating of the second state variable value may be achieved. FH240412PEP-2025112831.DOCX According to embodiments of the second aspect, the arithmetic decoder is configured update the first state variable value and the second state variable value using different adaptation time constants for the second group of bins. By updating the first state variable value and the second state variable value using different adaptation time constants, different statistic characteristics of the previously handled symbols can be reflected by the state variable values. It has been found that the availability of state variable values representing statistics of the handled symbols with different adaptation time constants is very helpful for an accurate adjustment of an interval size for the arithmetic coding (encoding / decoding) of the symbols. According to embodiments of the second aspect, the arithmetic decoder is configured to update the second state variable value with a longer adaptation time constant than the first state variable value for the second group of bins (wherein, for example, the adaptation time constant for the first state variable is defined by adaptRate0k, and wherein, for example, the adaptation time constant for the second state variable is defined by adaptRate1k). It was recognized that choosing a longer adaptation time constant for the second state variable value updating for the second group of bins is particularly efficient in combination with the scaled updating of the second state variable value on the basis of the first state variable value for the first group of bins. It was recognized that such a transition into an updating with such different adaptation time constants for the first and second state variable values is particularly advantageous. According to embodiments of the second aspect, the arithmetic decoder is configured to scale the first state variable value with a scaling value which is a potency of two for the first group of bins, in order to obtain the second state variable value (wherein, for example, the scaling value is a potency of two, wherein an exponent of the potency is determined by a difference between a number of bits used for a representation of the second state variable value and a number of bits used for a representation of the first state variable value). This allows for an efficient implementation of the updating of the state variable values. FH240412PEP-2025112831.DOCX According to embodiments of the second aspect, the arithmetic decoder is configured to obtain the second state variable value s1kon the basis of the first state variable value s0kaccording to ^^^^ ^^ ^^^^^^^^^^^^^^^^^^ −^^^^1 = ^^0 ∙ 2 1 ^^^^^^^^^^^^^^0for the first group of bins; wherein stateBits1is a number of bits used for a representation of the second state variable value, and wherein stateBits0is a number of bits used for a representation of the first state variable value. It was recognized that the above relationship enables an efficient coupling of an updating of the first and second state variable value. According to embodiments of the second aspect, the arithmetic decoder is configured to combine the first state variable value and the second state variable value using a weighted summation, in order to obtain a combined state variable value (wherein, for example, the first state variable value is weighted using scaling factor determined by a potency of 2, wherein an exponent of the potency of 2 is determined by a difference between the number of bits used for the representation of the second state variable value and a number of bits used for a representation of the first state variable value, and wherein, for example, the second state variable value is left unchanged; or wherein, for example, the second state variable value is weighted using scaling factor determined by a potency of 2, wherein an exponent of the potency of 2 is determined by a difference between the number of bits used for the representation of the first state variable value and a number of bits used for a representation of the second state variable value, and wherein, for example, the first state variable value is left unchanged), and wherein the arithmetic decoder is configured to derive the interval size information in dependence on the combined state variable values. It was recognized that a combining of state variable values enables an improved determination of the interval size information. For example, in particular in case the state variable values combined are based on different adaptation rates, the merging of such different information is advantageous for the determination of the interval size information. According to embodiments of the second aspect, the arithmetic decoder is configured to obtain a combined state variable value sk according to FH240412PEP-2025112831.DOCX wherein s0kis the first state variable value; wherein s1kis the second state variable value; wherein stateBits0 is a number of bits used to represent the first state variable value; wherein stateBits1 is a number of bits used to represent the second state variable value; and wherein ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ = 1 + ^^^^^^(^^^^^^^^^^^^^^^^^^0, ^^^^^^^^^^^^^^^^^^1);wherein max(.) is a maximum operator. It was recognized that the above approach enables an efficient merging of information of the first and second state variable values in order to determine the interval size information. For example, the combined state variable may be be converted into a LPS (less probable symbol) probability value (represented as unsigned integer) using a lookup table. FH240412PEP-2025112831.DOCX Embodiments according to a third aspect comprise an arithmetic decoder for decoding a plurality of symbols having symbol values (e.g. symbols of medical data; e.g. symbols describing EKG signals or EEG signals; e.g. symbols representing audio signals or video signals), wherein the arithmetic decoder is configured to derive an interval size value (e.g. rangeLPS; RLPS) (e.g. an interval size information defining an interval size associated with a symbol; e.g. an interval size information defining an interval size associated with a less probable symbol) (e.g. a width of an interval, e.g. an arithmetic coding interval, associated with a let probably symbol) for an arithmetic decoding of one or more symbol values to be decoded on the basis of one or more state variable values (e.g. sik), which represent statistics of a plurality of previously decoded symbol values, wherein the arithmetic decoder is configured to determine the interval size value (e.g. rangeLPS) using a probability table (e.g. ProbLPSMapping()), which represents probability values in an integer representation, wherein the arithmetic decoder is configured to select an entry (e.g. probLPSint) of the probability table in dependence on the one or more state variable values (e.g. using a combined state variable value, e.g. sk, which is obtained using a combination of two or more individual state variable values, e.g. s0k, s1k), and wherein the arithmetic decoder is configured to determine the interval size value (e.g. rangeLPS) in dependence on the selected entry. Furthermore, the probability table represents a probability of 0.5 using a table value 2probPrec-1, the probability table represents other probability values probExact (e.g. in a range 0<=probExact<0.5) using table values (e.g. integer table values or positive integer table values) which are equal to probExact*2probPrec+1except for a rounding effect; and probPrec is a number of bits used to represent respective entries of the probability table. It was recognized that representing a probability of 0.5 using a table value 2probPrec-1, e.g. instead of 2probPrec, representing other probability values probExact using table values which are equal to probExact*2probPrec+1(e.g. except for a rounding effect) enables saving 1 bit per table entry in the probability table. This can be explained in more detail with the following example: Consider the case that probPrec = 11, with probPrec being the number of bits used to represent respective entries of the probability table. If a probability is multiplied with 2probPrec= 211, the result is rounded to an integer value and stored in the table, then this would result in a table entry of 2048 for the highest possible LPS probability. However, this would no longer “fit” into a table entry comprising probPrec = 11 bit. Hence, representing a probability of 0.5 using a table value FH240412PEP-2025112831.DOCX 2probPrec-1 and other probability values probExact using table values which are equal to probExact*2probPrec+1brings along a clipping of the table entries (e.g. to 2047 for the above example). This may change or distort the probability values minimally, but saves one bit per value in the table. Hence, an improved compromise between an accuracy and bit demand for the probability table may be achieved. In particular, in parallelized architectures, wherein a plurality of probability tables may be processed in parallel, the bit savings for each instance of the probability table may provide significant benefits, e.g. in particular for devices with low memory capabilities. According to embodiments of the third aspect, the probability table represents (e.g. in subsequent entries having table entry indices from 0 to a predetermined maximum value) probability values probExact(i) according to ^^^^^^^^^^^^^^^^^^ = 0.5 ∙ ^^^^∙^^^^^^^^^^^^^^^^using table entries^^^^^^^^^^^^^^^^^^^^^^^^^^^^[^^] = max(1, min( (1 << ^^^^^^^^^^^^^^^^) − 1, ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^),wherein ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ = round (^^^^^^^^^^^^^^^^^^ ∙ 2^^^^^^^^^^^^^^^^+1), wherein exponent is apredetermined values (e.g. a potency of 2; e.g. ^^^^^^^^^^^^^^^^ = 212−^^^^^^^^^^^^^^^^^^^^^^, wherein, forexample, the probability table comprises 2probLPSbitsentries), wherein i is a table entry index between 0 (e.g. inclusive) and a predetermined maximum value; wherein α is a constant (e.g.0.9989407902), wherein probPrec is the number of bits used to represent respective entries of the probability table; wherein min(.) is a minimum operator; wherein max (.) is a maximum operator; wherein << is a bit shift operator (e.g. shift to the left by a specified number of bits); wherein round (.) is a rounding operation. According to embodiments of the third aspect, in the probability table a table entry representing a probability of 0.5 is clipped down to 2probPrec-1 (e.g. to reduce a number of bits required for a representation of the table entry)(wherein, for example, a “fair” table entry representing the probability of 0.5 would be 2probPrec). FH240412PEP-2025112831.DOCX According to embodiments of the third aspect, the probability table (e.g. ProbLPS mapping) takes the form ProbLPSmapping[]= [2047,2014,1980,1946,1914,1882,1850,1819,1788,1758,1729,1700,1671,1643, 1615,1588,1561,1535,1509,1484,1459,1434,1410,1387,1363,1340,1318,1296, 1274,1252,1231,1211,1190,1170,1151,1131,1112,1094,1075,1057,1039,1022, 1005,988,971,955,939,923,908,892,877,863,848,834,820,806,792,779,766,753, 740,728,716,704,692,680,669,658,647,636,625,614,604,594,584,574,564, 555,546,537,527,519,510,501,493,485,476,468,461,453,445,438,430,423, 416,409,402,395,389,382,376,369,363,357,351,345,339,334,328,323,317, 312,307,301,296,291,286,282,277,272,268,263,259,254,250,246,242,238, 234,230,226,222,218,215,211,208,204,201,197,194,191,187,184,181, 178,175,172,169,167,164,161,158,156,153,150,148,145,143,141,138, 136,134,131,129,127,125,123,121,119,117,115,113,111,109,107,105, 104,102 100, 98, 97, 95, 94, 92, 90, 89, 87, 86, 85, 83, 82, 80, 79, 78, 76, 75, 74, 73, 71, 70, 69, 68, 67, 66, 64, 63, 62, 61, 60, 59, 58, 57, 56, 55, 54, 53, 53, 52, 51, 50, 49, 48, 47, 47, 46, 45, 44, 44, 43, 42, 41, 41, 40, 39, 39, 38, 37, 37, 36, 36, 35, 34, 34, 33, 33, 32, 32, 31, 31, 30, 30, 29, 29, 28, 28, 27] (wherein, for example, probPrec is set to 11 and probLPSbits is set to 8). It was recognized that the above ProbLPSmapping[] enables an improved compromise between an accuracy and bit demand. According to embodiments of the third aspect, the arithmetic decoder is configured to determine the interval size value in dependence on a coding interval size (e.g. range; R), and the arithmetic decoder is configured to perform the arithmetic decoding of one or more symbols using the interval size value (e.g. RLPS). According to embodiments of the third aspect, the arithmetic decoder is configured to multiply an element (e.g. an entry) of the probability table (e.g. Prob_TabLPS) with a coding interval size (e.g. range), in order to obtain the interval size value (e.g. rangeLPS). It was recognized that this enables an efficient determination of the interval size value. FH240412PEP-2025112831.DOCX According to embodiments of the third aspect, the arithmetic decoder is configured to apply a bit shift operation discarding one or more least significant bits (e.g. >> (probPrec+1)) to a product between a selected element (e.g. an entry) of the probability table (e.g. probLPSint) and a coding interval size (e.g. range), in order to obtain the interval size value (e.g. rangeLPS). Hence, this determination of the interval size value has been found to be computationally efficient and to provide good quality results. The probability table can be comparatively small, and the scaling function can be implemented in a computationally efficient manner, using bit shift operations. According to embodiments of the third aspect, the arithmetic decoder is configured to obtain a combined state variable value (e.g. sk), and the arithmetic decoder is configured to select an entry of the probability table (e.g. ProbLPS mapping with 2probLPSbitsentries) in dependence on the combined state variable value (e.g. in dependence on an absolute value of the combined state variable value or in dependence on an absolute value of a more significant portion (e.g. comprising one or more more-significant bits) of the combined state variable value while a less significant portion (e.g. comprising one or more less significant bits) of the combined state variable value is neglected). It was recognized that a combining of state variable values enables an improved determination of the interval size information. For example, in particular in case the state variable values combined are based on different adaptation rates, the merging of such different information is advantageous for the determination of the interval size information. According to embodiments of the third aspect, the arithmetic decoder is configured to obtain a selected entry probLPSint of the probability table ProbLPSmapping according to ^^^^^^^^^^^^^^^^^^^^ = ProbLPSmapping[abs(^^^^ >> (stateBitsCombined − probLPSbits − 1))]wherein sk is a combined state variable value; wherein abs (.) is an absolute value operator; wherein >> is a bit-shift-to-the-right operator; wherein stateBitsCombined is a number of bits necessary to represent sk (e.g. to represent all possible values of sk) as signed integer in 2’s complement representation. FH240412PEP-2025112831.DOCX It was found that the above table entry selections is particularly efficient. According to embodiments of the third aspect, the arithmetic decoder is configured to obtain an interval size value rangeLPS (e.g. describing a size of an interval associated with a less probable symbol) usingrangeLPS = (^^^^^^^^^^ ∙ ^^^^^^^^^^^^^^^^^^^^) >> (^^^^^^^^^^^^^^^^ + 1)or using rangeLPS = (^^^^^^^^^^ ∙ ^^^^^^^^^^^^^^^^^^^^ + (1 << ^^^^^^^^^^^^^^^^)) >> (^^^^^^^^^^^^^^^^ + 1)wherein range is a coding interval size (e.g. a total coding interval size), wherein probLPSint is an entry (e.g. a selected entry) of the probability table (e.g. of the probability table ProbLPSmapping) (e.g. selected in dependence on the combined state variable value), wherein probPrec is a number of bits necessary to store elements of the probability table (e.g. ProbLPSmapping) as unsigned integers. Hence, the width of the less probable symbols, rangeLPS, can be derived using different rounding approaches, for example enabling a scaling of the accuracy depending on the rounding chosen. According to embodiments of the third aspect, the arithmetic decoder is configured toenforce that the interval size value is larger than zero (e.g. using an operation rangeLPS =max(1, rangeLPS)).According to embodiments of the third aspect, the arithmetic decoder is configured to determine the one or more state variable values and / or the combined state variable value according to one of claims 49 to 84. FH240412PEP-2025112831.DOCX Embodiments according to the first aspect comprise an arithmetic encoder for encoding a plurality of symbols having symbol values (e.g. symbols of medical data; e.g. symbols describing EKG signals or EEG signals; e.g. symbols representing audio signals or video signals), wherein the arithmetic encoder is configured to determine one or more state variable values (e.g. s1k, s2k), which represent statistics of a plurality of previously encoded symbol values, and wherein the arithmetic encoder is configured to derive an interval size information (e.g. pk, R*pk;) for an arithmetic encoding of one or more symbol values to be encoded on the basis of one or more state variable values which represent statistics of a plurality of previously encoded symbol values (e.g. on the basis of a plurality of state variable values (e.g. sik), which represent statistics of a plurality of previously encoded symbol values with different adaptation time constants) (wherein, for example, the arithmetic encoder is configured to map the one or more state variable values, in order to obtain the interval size information describing an interval size for the arithmetic encoding of one or more symbols to be encoded) (wherein, for example, the arithmetic encoder is configured to map a combined state variable value, or a scaled and / or rounded version thereof, using a lookup-table (e.g. LUT1 or ProbLPSmapping) in order to obtain the interval size information describing an interval size for the arithmetic encoding of one or more symbols to be encoded). Furthermore, the arithmetic encoder is configured to selectively increase an adaptation speed of one or more of the state variable values (e.g. of a single one of the one more state variable values, or of all of the one or more state variable values) (e.g. a speed at which the one or more state variable values are adapted to a probability of encoded symbol values) for a predetermined number of bins following an initialization of the one or more state variable values; and / or the arithmetic encoder is configured to selectively reduce an adaptation speed of one or more of the state variable values (e.g. of a single one of the one more state variable values, or of all of the one or more state variable values) (e.g. a speed at which the one or more state variable values are adapted to a probability of encoded symbol values) when a predetermined number of bins following an initialization of one or more state variable values has passed (e.g. has been used for an adaptation of one or more of the state variable values using a comparatively higher adaptation speed); and / or the arithmetic encoder is configured to use a first, comparatively higher (e.g. faster) adaptation speed for adapting one or more of the state variable values to a probability (e.g. to an actual rate of occurrence) of encoded symbol values for a first group of bins following an initialization of the one or more state variable values, and to use a second, comparatively FH240412PEP-2025112831.DOCX lower adaptation speed (e.g. lower that the first adaptation speed) for adapting one or more of the state variable values to a probability (e.g. to an actual rate of occurrence) of encoded symbol values for a second group of bins following the first group of bins (e.g. for the remaining bins following the first group of bins). According to embodiments of the first aspect, the arithmetic encoder is configured to selectively modify a scaling value (e.g. nik), which adjusts a magnitude of a change of one or more of the state variable values, which occurs in response to an encoded symbol, in dependence on a counting of bins processed since an initialization of the one or more state variable values. According to embodiments of the first aspect, the arithmetic encoder is configured todetermine an increment value (e.g. ⌊^^[^^ + ⌊ ), by which one or more of the state variable values (e.g. ^^^^^^) are incremented in case that a symbol to be encoded takesa first symbol value (e.g. “1”), in dependence on a scaling value (^^. ^^ ^^^^^^); the arithmeticencoder is configured to determine a decrement value (e.g. ⌊^^[^^ + ⌊ − ^^ ^^ ^^^^ ∙ ^^^^ ⌋] ∙ ^^^^^^⌋ ), by which one or more of the state variable values (e.g. ^^^^^^) are decremented in case that a symbol to be encoded takes a second symbol value (e.g. “0”), in dependence on the scaling value (e.g. ^^^^^^); and the arithmetic encoder is configured to gradually or step-wisely reduce the scaling value in dependence on a number of bins processed since an initialization of the one or more state variable values. According to embodiments of the first aspect, the arithmetic encoder is configured to set thescaling value (^^. ^^ ^^^^^^) to a first value for a first plurality of bins (e.g. for 63 bins) following an initialization of the one or more state variable values (e.g. ^^^^^^), and the arithmetic encoderis configured to set the scaling value (^^. ^^ ^^^^^^) to a second value, which is smaller than the first value, for a second plurality of bins following the first plurality of bins. According to embodiments of the first aspect, the arithmetic encoder is configured to update a first state variable value (e.g. sk1) in dependence on a symbol to be encoded and using a look-up table (e.g. A); the arithmetic encoder is configured to scale a table value (e.g.^^[^^ + ) obtained using the look-up table using a scaling value (e.g. using a first scaling value)(e.g. ^^^^^^), in order to obtain an increment value by which the first state variable value is incremented or a decrement value by which the first state variable value is decremented. FH240412PEP-2025112831.DOCX According to embodiments of the first aspect, the arithmetic encoder is configured to update a second state variable value (e.g. sk2) in dependence on a symbol to be encoded and using a look-up table (e.g. A); and the arithmetic encoder is configured to scale a table value (e.g.^^[^^ + ) obtained using the look-up table using a scaling value (e.g. using a second scaling value, e.g. ) ^^^^^^), in order to obtain an increment value by which the second state variable value is incremented or a decrement value by which the second state variable value is decremented. According to embodiments of the first aspect, the arithmetic encoder is configured update the first state variable value and the second state variable value using different adaptation time constants at least for the second group of bins. According to embodiments of the first aspect, the arithmetic encoder is configured to selectively increase or decrease a previous state variable value by a value determined using the look-up table in dependence on whether a symbol to be encoded takes a first value (e.g. “1”) or a second value (e.g. “0”) which is different from the first value. According to embodiments of the first aspect, a magnitude of the increase or decrease is dependent on a number of bins processed since an initialization of the one or more state variable values. According to embodiments of the first aspect, the arithmetic encoder is configured to increase a previous state variable value by a comparatively larger value in case that the previous state variable value is negative when compared to a case that the previous state variable value is positive if a symbol to be encoded takes a first value; and the arithmetic encoder is configured to decrease a previous state variable value by a comparatively larger value in case that the previous state variable value is positive when compared to a case that the previous state variable value is negative if a symbol to be encoded takes a second value which is different from the first value. According to embodiments of the first aspect, the arithmetic encoder is configured to determine an index of an entry of the lookup table to be evaluated when updating the first state variable value in dependence on a sum of a predetermined offset value (e.g. z) and a previously computed first state variable value (e.g. ^^1^^), or a scaled and / or rounded version (e.g. thereof, if a symbol to be encoded takes a first value; and the FH240412PEP-2025112831.DOCX arithmetic encoder is configured to determine an index of an entry of the lookup table to be evaluated when updating the first state variable value in dependence on a sum of a predetermined offset value (e.g. z) and a in inversed version (e.g. −^^1^^) of a previously computed first state variable value, or a scaled and / or rounded version (e.g. thereof, if a symbol to be encoded takes a second value. According to embodiments of the first aspect, the arithmetic encoder is configured to determine an index of an entry of the lookup table to be evaluated when updating the second state variable value in dependence on a sum of a predetermined offset value (e.g. z) and a previously computed second state variable value (e.g. ^^2^^), or a scaled and / or rounded version (e.g. ⌊ ^^^^2 ) thereof, if a symbol to be encoded takes a first value; and the arithmetic encoder is configured to determine an index of an entry of the lookup table to be evaluated when updating the second state variable value in dependence on a sum of a predetermined offset value (e.g. z) and a in inversed version (e.g. −^^2^^) of a previously computed second state variable value, or a scaled and / or rounded version ) thereof, if a symbol to be encoded takes a second value. According to embodiments of the first aspect, the arithmetic encoder is configured to apply a first scaling value (e.g. mk1), to scale the previously computed first state variable value (e.g. sk1), when determining an index of an entry of the lookup table to be evaluated when updating the first state variable value, and the arithmetic encoder is configured to apply a second scaling value (e.g. mk2), to scale the previously computed second state variable value (e.g. sk2), when determining an index of an entry of the lookup table to be evaluated when updating the second state variable value, wherein the first scaling value is different from the second scaling value. According to embodiments of the first aspect, the arithmetic encoder is configured to scale a value returned by an evaluation of the lookup table using a first scaling value when updating the first state variable value and the arithmetic encoder is configured to scale a value returned by an evaluation of the lookup table using a second scaling value when updating the second state variable value, wherein the first scaling value is different from the second scaling value. According to embodiments of the first aspect, the arithmetic encoder is configured to determine one or more updated state variable values ^^^^^^according to FH240412PEP-2025112831.DOCX wherein A is a lookup table, wherein z is a predetermined offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^are one or more weighting values. According to embodiments of the first aspect, a number of state variables (e.g. per context model) is equal to 2; wherein ^^ = {157, 143, 129, 115, 101, 87, 73, 59, 45, 35, 29, 23, 17, 13, 9, 5,4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 0};wherein z=16; wherein ^^^^^^^^^^^^^^^^^^^^is a number (e.g. a minimum number) of bits sufficient to represent state ^^^^^^(e.g. all possible values of ^^^^^^) as a signed integer in 2's complement representation; wherein ^^^^^^ = 25−^^^^^^^^^^^^^^^^^^^^; wherein ^^^^^^^^^^^^^^^^^^^^^^is an adaptation rate parameter associated with state variable (e.g. “hypothesis”) (wherein, for example, ^^^^^^^^^^^^^^^^^^^^^^takes a comparatively smaller value for a first group of bins following an initialization of the one or more state variable value, and wherein, for example, ^^^^^^^^^^^^^^^^^^^^^^takes a second, comparatively larger value for a second group of bins following the first group of bins); According to embodiments of the first aspect, the arithmetic encoder is configured to initialize a counter with a predetermined value (e.g. countInit; e.g countinit=63) before encoding a first bin (e.g. symbol) associated with a given context model (e.g. a context model having context model index k); and the arithmetic encoder is configured to update the counter after encoding a respective bin associated with the given context model (e.g. by step-wisely decrementing the counter by one (e.g. per encoded bin) in response to an encoding of a respective bin associated with the given context model, until the counter hasreached a value of zero) (e.g. by setting ^^^^^^^^^^^^ to ^^^^^^(0, ^^^^^^^^^^^^ − 1) in response to anencoding of a respective bin associated with the given context model). FH240412PEP-2025112831.DOCXAccording to embodiments of the first aspect, countInit=63; ^^^^^^^^^^^^^^^^^^0 = 10; ^^^^^^^^^^^^^^^^^^1 =13; ^^^^^^^^^^^^^^^^^^^^ 1, ^^^^ ^^^^^^^^^^ > 0 1, ^^^^ ^^^0 = { ^^2, ^^^^ℎ^^^^^^^^^^^^. ; and ^^^^^^^^^^^^^^^^^^^^1 = { ^^^^^^^^^ > 05, ^^^^ℎ^^^^^^^^^^^^. . According to embodiments of the first aspect, the arithmetic encoder is configured to determine one or more updated state variable values ^^^^^^according to wherein A is a lookup table, wherein z is a predetermined offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^are one or more weighting values. According to embodiments of the first aspect, the arithmetic encoder is configured to determine one or more updated state variable values ^^^^^^according to wherein A is a lookup table, wherein z is a predetermined offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^are one or more weighting values. According to embodiments of the first aspect, the arithmetic encoder is configured to determine one or more updated state variable values ^^^^^^according to wherein A is a lookup table, wherein z is a predetermined offset value; FH240412PEP-2025112831.DOCX wherein ^^^^^^are one or more weighting values; wherein ^^^^^^are one or more weighting values. According to embodiments of the first aspect, the entries of A decrease monotonically with increasing lookup table index. According to embodiments of the first aspect, A is or deviates therefrom merely for one or more extreme values of its argument by zero setting or magnitude reduction to avoid the updated ^^^^^^leaving a predetermined value range, where ^^^^^^^^^^^^, ^̂^, ^̂^^^, and ^̂^^^are predetermined parameters. According to embodiments of the first aspect, a last entry of the lookup table is equal to zero. According to embodiments of the first aspect, the arithmetic encoder is configured to apply a clipping operation to the updated state variable values, to keep the updated and clipped state variable values within a predetermined range of values. According to embodiments of the first aspect, the arithmetic encoder is configured to apply a clipping operation according to ^^^^^^ = ^^^^^^(^^^^^^(^^ ^^ ^^^^ , ℎ^^ ), ^^^^^^) to the updated state variable values, wherein ^^^^^^is a maximum allowed value for ^^^^^^, and wherein ℎ^^^^is a minimum allowed value for ^^^^^^. According to embodiments of the first aspect, the arithmetic encoder is configured to apply different scaling values for different context models. According to embodiments of the first aspect, the arithmetic encoder is configured to obtain the interval size information as defined in one of embodiments 1 to 55 (as discussed later). FH240412PEP-2025112831.DOCX According to embodiments of the first aspect, the arithmetic encoder is configured to update a first state variable value (sk0) in dependence on a symbol to be encoded (for example, using a look-up table (A)); the arithmetic encoder is configured to derive a second state variable value (sk1) on the basis of the first state variable value for a first group of bins following an initialization of the two or more state variable values (e.g. for a predetermined number of bins following an initialization of the one or more state variable values), and the arithmetic encoder is configured to update the second state variable value (sk1) in dependence on a symbol to be encoded for a second group of bins following the first group of bins (e.g. when a predetermined number of bins following an initialization of one or more state variable values has passed) (wherein, for example, deriving the second state variable value on the basis of the first state variable value for the first group of bins following the initialization of the two or more state variable values has the effect that adaptation speed for adapting the first state variable value and the second state variable value to a probability (e.g. to an actual rate of occurrence) of encoded symbol values is comparatively high for the first group of bins following an initialization of the state variable values, and that the adaptation of the first state variable value and of the second state variable value is highly efficient for the first group of bins following the initialization of the state variable values) FH240412PEP-2025112831.DOCX Embodiments according to the second aspect comprise an arithmetic encoder for encoding a plurality of symbols having symbol values (e.g. symbols of medical data; e.g. symbols describing EKG signals or EEG signals; e.g. symbols representing audio signals or video signals), wherein the arithmetic encoder is configured to determine a plurality of (two or more) state variable values (e.g. s0k, s1k), which represent statistics of a plurality of previously encoded symbol values, and wherein the arithmetic encoder is configured to derive an interval size information (e.g. pk, R*pk) for an arithmetic encoding of one or more symbol values to be encoded on the basis of the two or more state variable values (e.g. sik), which represent statistics of a plurality of previously encoded symbol values. Furthermore, the arithmetic encoder is configured to update a first state variable value (e.g. sk0) in dependence on a symbol to be encoded (for example, using a look-up table (e.g. A)); the arithmetic encoder is configured to derive a second state variable value (sk1) on the basis of the first state variable value for a first group of bins following an initialization of the one or more state variable values (e.g. for a predetermined number of bins following an initialization of the one or more state variable values), and the arithmetic encoder is configured to update the second state variable value (e.g. sk1) in dependence on a symbol to be encoded for a second group of bins following the first group of bins (e.g. when a predetermined number of bins following an initialization of one or more state variable values has passed). According to embodiments of the second aspect, the arithmetic encoder is configured to scale the first state variable value, in order to derive the second state variable value from the first state variable value for a first group of bins following an initialization of the one or more state variable values (e.g. such that the second state variable value is a scaled version of the first state variable value for the first group of bins following the initialization of the one or more state variable values, e.g. such that the second state variable value follows the first state variable value in a substantially proportional manner for the first group of bins following the initialization of the one or more state variable values, and such that the second state variable value is determined independently from the first state variable value for the second group of bins). According to embodiments of the second aspect, the arithmetic encoder is configured update the first state variable value and the second state variable value using different adaptation time constants for the second group of bins. FH240412PEP-2025112831.DOCX According to embodiments of the second aspect, the arithmetic encoder is configured to update the second state variable value with a longer adaptation time constant than the first state variable value for the second group of bins (wherein, for example, the adaptation time constant for the first state variable is defined by adaptRate0k, and wherein, for example, the adaptation time constant for the second state variable is defined by adaptRate1k). According to embodiments of the second aspect, the arithmetic encoder is configured to scale the first state variable value with a scaling value which is a potency of two for the first group of bins, in order to obtain the second state variable value (wherein, for example, the scaling value is a potency of two, wherein an exponent of the potency is determined by a difference between a number of bits used for a representation of the second state variable value and a number of bits used for a representation of the first state variable value). According to embodiments of the second aspect, the arithmetic encoder is configured to obtain the second state variable value s1kon the basis of the first state variable value s0kaccording to ^^^^ ^^ ^^^^^^^^^^^^^^^^^^ −^^^^^^^^^^^^^^1 = ^^0 ∙ 2 1 ^^^^0for the first group of bins; wherein stateBits1 is a number of bits used for a representation of the second state variable value, and wherein stateBits0 is a number of bits used for a representation of the first state variable value. According to embodiments of the second aspect, the arithmetic encoder is configured to combine the first state variable value and the second state variable value using a weighted summation, in order to obtain a combined state variable value (wherein, for example, the first state variable value is weighted using scaling factor determined by a potency of 2, wherein an exponent of the potency of 2 is determined by a difference between the number of bits used for the representation of the second state variable value and a number of bits used for a representation of the first state variable value, and wherein, for example, the second state variable value is left unchanged; or wherein, for example, the second state variable value is weighted using scaling factor determined by a potency of 2, wherein an exponent of the potency of 2 is determined by a difference between the number of bits used for the representation of the first state variable value and a number of bits used for a representation of the second state variable value, and wherein, for example, the first state FH240412PEP-2025112831.DOCX variable value is left unchanged). Furthermore, the arithmetic encoder is configured to derive the interval size information in dependence on the combined state variable values. According to embodiments of the second aspect, the arithmetic encoder is configured to obtain a combined state variable value skaccording to wherein s0kis the first state variable value; wherein s1kis the second state variable value; wherein stateBits0 is a number of bits used to represent the first state variable value; wherein stateBits1 is a number of bits used to represent the second state variable value; and wherein ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ = 1 + ^^^^^^(^^^^^^^^^^^^^^^^^^0, ^^^^^^^^^^^^^^^^^^1);wherein max(.) is a maximum operator. FH240412PEP-2025112831.DOCX Embodiments according to the third aspect comprise an arithmetic encoder for encoding a plurality of symbols having symbol values (e.g. symbols of medical data; e.g. symbols describing EKG signals or EEG signals; e.g. symbols representing audio signals or video signals), wherein the arithmetic encoder is configured to derive an interval size value (e.g. rangeLPS; RLPS) (e.g. an interval size information defining an interval size associated with a symbol; e.g. an interval size information defining an interval size associated with a less probable symbol) (e.g. a width of an interval, e.g. an arithmetic coding interval, associated with a let probably symbol) for an arithmetic encoding of one or more symbol values to be encoded on the basis of one or more state variable values (e.g. sik), which represent statistics of a plurality of previously encoded symbol values and wherein the arithmetic encoder is configured to determine the interval size value (e.g. rangeLPS) using a probability table (e.g. ProbLPSMapping()), which represents probability values in an integer representation. Furthermore, the arithmetic encoder is configured to select an entry (e.g. probLPSint) of the probability table in dependence on the one or more state variable values (e.g. using a combined state variable value, e.g. sk, which is obtained using a combination of two or more individual state variable values, e.g. s0k, s1k), and the arithmetic encoder is configured to determine the interval size value (e.g. rangeLPS) in dependence on the selected entry; wherein the probability table represents a probability of 0.5 using a table value 2probPrec-1, and wherein the probability table represents other probability values probExact (e.g. in a range 0<=probExact<0.5) using table values (e.g. integer table values or positive integer table values) which are equal to probExact*2probPrec+1except for a rounding effect; wherein probPrec is a number of bits used to represent respective entries of the probability table. According to embodiments of the second aspect, the probability table represents (e.g. in subsequent entries having table entry indices from 0 to a predetermined maximum value) probability values probExact(i) according to ^^^^^^^^^^^^^^^^^^ = 0.5 ∙ ^^^^∙^^^^^^^^^^^^^^^^using table entries^^^^^^^^^^^^^^^^^^^^^^^^^^^^[^^] = max(1, min( (1 << ^^^^^^^^^^^^^^^^) − 1, ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^),wherein FH240412PEP-2025112831.DOCX^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ = round (^^^^^^^^^^^^^^^^^^ ∙ 2^^^^^^^^^^^^^^^^+1)wherein exponent is a predetermined values (e.g. a potency of 2; e.g. ^^^^^^^^^^^^^^^^ =212−^^^^^^^^^^^^^^^^^^^^^^, wherein, for example, the probability table comprises 2probLPSbitsentries), wherein i is a table entry index between 0 (e.g. inclusive) and a predetermined maximum value; wherein α is a constant (e.g.0.9989407902), probPrec is the number of bits used to represent respective entries of the probability table; wherein min(.) is a minimum operator; wherein max (.) is a maximum operator; wherein << is a bit shift operator (e.g. shift to the left by a specified number of bits); and wherein round (.) is a rounding operation. According to embodiments of the second aspect, in the probability table a table entry representing a probability of 0.5 is clipped down to 2probPrec-1 (e.g. to reduce a number of bits required for a representation of the table entry)(wherein, for example, a “fair” table entry representing the probability of 0.5 would be 2probPrec). According to embodiments of the second aspect, the probability table (e.g. ProbLPS mapping) takes the form ProbLPSmapping[]= [2047,2014,1980,1946,1914,1882,1850,1819,1788,1758,1729,1700,1671,1643, 1615,1588,1561,1535,1509,1484,1459,1434,1410,1387,1363,1340,1318,1296, 1274,1252,1231,1211,1190,1170,1151,1131,1112,1094,1075,1057,1039,1022, 1005,988,971,955,939,923,908,892,877,863,848,834,820,806,792,779,766,753, 740,728,716,704,692,680,669,658,647,636,625,614,604,594,584,574,564, 555,546,537,527,519,510,501,493,485,476,468,461,453,445,438,430,423, 416,409,402,395,389,382,376,369,363,357,351,345,339,334,328,323,317, 312,307,301,296,291,286,282,277,272,268,263,259,254,250,246,242,238, 234,230,226,222,218,215,211,208,204,201,197,194,191,187,184,181, 178,175,172,169,167,164,161,158,156,153,150,148,145,143,141,138, 136,134,131,129,127,125,123,121,119,117,115,113,111,109,107,105, 104,102 100, 98, 97, 95, 94, 92, 90, 89, 87, 86, 85, 83, 82, 80, 79, 78, 76, 75, 74, 73, 71, 70, 69, 68, 67, 66, 64, 63, 62, 61, 60, 59, 58, 57, 56, 55, 54, 53, 53, 52, 51, 50, 49, 48, 47, 47, 46, 45, 44, 44, 43, 42, 41, 41, 40, 39, 39, 38, 37, 37, 36, 36, 35, 34, 34, 33, 33, 32, 32, 31, 31, 30, 30, 29, 29, 28, 28, 27] FH240412PEP-2025112831.DOCX (wherein, for example, probPrec is set to 11 and probLPSbits is set to 8). According to embodiments of the second aspect, the arithmetic encoder is configured to determine the interval size value in dependence on a coding interval size (e.g. range; R), and the arithmetic encoder is configured to perform the arithmetic encoding of one or more symbols using the interval size value (RLPS). According to embodiments of the second aspect, the arithmetic encoder is configured to multiply an element (e.g. an entry) of the probability table (e.g. Prob_TabLPS) with a coding interval size (e.g. range), in order to obtain the interval size value (e.g. rangeLPS). According to embodiments of the second aspect, the arithmetic encoder is configured to apply a bit shift operation discarding one or more least significant bits (e.g. >> (probPrec+1)) to a product between a selected element (e.g. an entry) of the probability table (e.g. probLPSint) and a coding interval size (e.g. range), in order to obtain the interval size value (e.g. rangeLPS). According to embodiments of t...

Claims

Claims 1. An arithmetic encoder (34;400) for encoding a plurality of symbols (24’’, 410) having symbol values, wherein the arithmetic encoder is configured to determine one or more state variable values (s1k, s2k; 642,644; 710;810;910;1010a,1010b;1082a,1082b;1110;1210;1310; 1410;1510;1632,1642;1732,1742,1812,1820,1912,1914,1922,1924,2010), which represent statistics of a plurality of previously encoded symbol values, and wherein the arithmetic encoder is configured to derive an interval size information (pk, R*pk;, rangeLPS; 432;534;620;720;820;820;1020;1084;1120;1320;1420;1520;1662;1762,2020) for an arithmetic encoding of one or more symbol values to be encoded on the basis of one or more state variable values which represent statistics of a plurality of previously encoded symbol values wherein the arithmetic encoder is configured to selectively increase an adaptation speed of one or more of the state variable values for a predetermined number of bins following an initialization of the one or more state variable values; and / or wherein the arithmetic encoder is configured to selectively reduce an adaptation speed of one or more of the state variable values when a predetermined number of bins following an initialization of one or more state variable values has passed; and / or wherein the arithmetic encoder is configured to use a first, comparatively higher adaptation speed for adapting one or more of the state variable values to a probability of encoded symbol values for a first group of bins following an initialization of the one or more state variable values, and to use a second, comparatively lower adaptation speed for adapting one or more of the state variable values to a probability of encoded symbol values for a second group of bins following the first group of bins.

2. The arithmetic encoder according to claim 1, wherein the arithmetic encoder is configured to selectively modify a scaling value, which adjusts a magnitude of a change of one or more of the state variable values, which occurs in response to an encoded symbol, in dependence on a counting of bins processed since an initialization of the one or more state variable values. FH240412PEP-2025112831.DOCX3. The arithmetic encoder according to claim 1 or 2, wherein the arithmetic encoder is configured to determine an increment value, by which one or more of the state variable values are incremented in case that a symbol to be encoded takes a first symbol value, in dependence on a scaling value; wherein the arithmetic encoder is configured to determine a decrement value, by which one or more of the state variable values are decremented in case that a symbol to be encoded takes a second symbol value, in dependence on the scaling value; and wherein the arithmetic encoder is configured to gradually or step-wisely reduce the scaling value in dependence on a number of bins processed since an initialization of the one or more state variable values.

4. The arithmetic encoder according to one of claims 1 to 3, wherein the arithmetic encoder is configured to set the scaling value to a first value for a first plurality of bins following an initialization of the one or more state variable values, and wherein the arithmetic encoder is configured to set the scaling value to a second value, which is smaller than the first value, for a second plurality of bins following the first plurality of bins.

5. The arithmetic encoder according to one of claims 1 to 4, wherein the arithmetic encoder is configured to update a first state variable value (sk1) in dependence on a symbol to be encoded and using a look-up table (A); wherein the arithmetic encoder is configured to scale a table value obtained using the look- up table using a scaling value, in order to obtain an increment value by which the first state variable value is incremented or a decrement value by which the first state variable value is decremented.

6. The arithmetic encoder according to one of claims 1 to 5, wherein the arithmetic encoder is configured to update a second state variable value (sk2) in dependence on a symbol to be encoded and using a look-up table (A); FH240412PEP-2025112831.DOCXwherein the arithmetic encoder is configured to scale a table value obtained using the look- up table using a scaling value, in order to obtain an increment value by which the second state variable value is incremented or a decrement value by which the second state variable value is decremented.

7. The arithmetic encoder according to one of claims 1 to 6, wherein the arithmetic encoder is configured update the first state variable value and the second state variable value using different adaptation time constants at least for the second group of bins.

8. The arithmetic encoder according to one of claims 1 to 7, wherein the arithmetic encoder is configured to selectively increase or decrease a previous state variable value by a value determined using the look-up table in dependence on whether a symbol to be encoded takes a first value or a second value which is different from the first value.

9. The arithmetic encoder according to one of claims 1 to 8, wherein a magnitude of the increase or decrease is dependent on a number of bins processed since an initialization of the one or more state variable values.

10. The arithmetic encoder according to one of claims 1 to 9, wherein the arithmetic encoder is configured to increase a previous state variable value by a comparatively larger value in case that the previous state variable value is negative when compared to a case that the previous state variable value is positive if a symbol to be encoded takes a first value; and wherein the arithmetic encoder is configured to decrease a previous state variable value by a comparatively larger value in case that the previous state variable value is positive when compared to a case that the previous state variable value is negative if a symbol to be encoded takes a second value which is different from the first value.

11. The arithmetic encoder according to one of claims 1 to 10, wherein the arithmetic encoder is configured to determine an index of an entry of the lookup table to be evaluated when updating the first state variable value in dependence on a sum of a predetermined offset value (z) and a previously computed first state variable value ( ^^1^^), or a scaled and / or rounded version thereof, if a symbol to be encoded takes a first value; and FH240412PEP-2025112831.DOCXwherein the arithmetic encoder is configured to determine an index of an entry of the lookup table to be evaluated when updating the first state variable value in dependence on a sum of a predetermined offset value (z) and a in inversed version ( −^^1^^) of a previously computed first state variable value, or a scaled and / or rounded version thereof, if a symbol to be encoded takes a second value.

12. The arithmetic encoder according to one of claims 1 to 11, wherein the arithmetic encoder is configured to determine an index of an entry of the lookup table to be evaluated when updating the second state variable value in dependence on a sum of a predetermined offset value (z) and a previously computed second state variable value ( ^^2^^), or a scaled and / or rounded version thereof, if a symbol to be encoded takes a first value; and wherein the arithmetic encoder is configured to determine an index of an entry of the lookup table to be evaluated when updating the second state variable value in dependence on a sum of a predetermined offset value (z) and a in inversed version ( −^^2^^) of a previously computed second state variable value, or a scaled and / or rounded version thereof, if a symbol to be encoded takes a second value.

13. The arithmetic encoder according to one of claims 1 to 12, wherein the arithmetic encoder is configured to apply a first scaling value (mk1), to scale the previously computed first state variable value (sk1), when determining an index of an entry of the lookup table to be evaluated when updating the first state variable value, and wherein the arithmetic encoder is configured to apply a second scaling value (mk2), to scale the previously computed second state variable value (sk2), when determining an index of an entry of the lookup table to be evaluated when updating the second state variable value, wherein the first scaling value is different from the second scaling value.

14. The arithmetic encoder according to one of claims 1 to 13, wherein the arithmetic encoder is configured to scale a value returned by an evaluation of the lookup table using a first scaling value when updating the first state variable value, FH240412PEP-2025112831.DOCXwherein the arithmetic encoder is configured to scale a value returned by an evaluation of the lookup table using a second scaling value when updating the second state variable value, wherein the first scaling value is different from the second scaling value.

15. The arithmetic encoder according to one of claims 1 to 14, wherein the arithmetic encoder is configured to determine one or more updated state variable values ^^^^^^according towherein A is a lookup table, wherein z is a predetermined offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^are one or more weighting values.

16. The arithmetic encoder according to one of claims 1 to 15, wherein a number of state variables is equal to 2;wherein ^^ = {157, 143, 129, 115, 101, 87, 73, 59, 45, 35, 29, 23, 17, 13, 9, 5,4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 0};wherein z=16; wherein ^^^^^^^^^^^^^^^^^^^^is a number of bits sufficient to represent state ^^^^^^as a signed integer in 2's complement representation; wherein ^^^^ 5−^^^^^^^^^^^^^^^^^^ = 2 ^^^^;wherein ^^^^^^^^^^^^^^^^^^^^^^is an adaptation rate parameter associated with state variable ^^^^^^; wherein17. The arithmetic encoder according to one of claims 1 to 16, wherein the arithmetic encoder is configured to initialize a counter with a predetermined value before encoding a first bin associated with a given context model; and FH240412PEP-2025112831.DOCXwherein the arithmetic encoder is configured to update the counter after encoding a respective bin associated with the given context model.

18. The arithmetic encoder according to one of claims 1 to 17, wherein countInit=63;wherein ^^^^^^^^^^^^^^^^^^0 = 10;wherein ^^^^^^^^^^^^^^^^^^1 = 13;19. The arithmetic encoder according to one of claims 1 to 18, wherein the arithmetic encoder is configured to determine one or more updated state variable values ^^^^^^according towherein A is a lookup table, wherein z is a predetermined offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^are one or more weighting values.

20. The arithmetic encoder according to one of claims 1 to 19, wherein the arithmetic encoder is configured to determine one or more updated state variable values ^^^^^^according towherein A is a lookup table, FH240412PEP-2025112831.DOCXwherein z is a predetermined offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^are one or more weighting values.

21. The arithmetic encoder according to one of claims 1 to 20, wherein the arithmetic encoder is configured to determine one or more updated state variable values ^^^^^^according towherein A is a lookup table, wherein z is a predetermined offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^are one or more weighting values.

22. The arithmetic encoder according to one of claims 1 to 21, wherein the entries of A decrease monotonically with increasing lookup table index.

23. The arithmetic encoder according to one of claims 1 to 22, wherein A isor deviates therefrom merely for one or more extreme values of its argument by zero setting or magnitude reduction to avoid the updated ^^^^^^leaving a predetermined value range, where ^^^^^^^^^^^^, ^̂^, ^̂^^^, and ^̂^^^are predetermined parameters.

24. The arithmetic encoder according to one of claims 1 to 23, wherein a last entry of the lookup table is equal to zero. FH240412PEP-2025112831.DOCX25. The arithmetic encoder according to one of claims 1 to 24, wherein the arithmetic encoder is configured to apply a clipping operation to the updated state variable values, to keep the updated and clipped state variable values within a predetermined range of values.

26. The arithmetic encoder according to one of claims 1 to 25, wherein the arithmetic encoder is configured to apply a clipping operation according to ^^^^^^ = ^^^^^^(^^^^^^(^^ ^^^^ , ℎ ^^^^ ), ^^^^^^) to the updated state variable values, wherein ^^^^^^is a maximum allowed value for ^^^^^^, and wherein ℎ^^^^is a minimum allowed value for ^^^^^^.

27. The arithmetic encoder according to one of claims 1 to 26, wherein the arithmetic encoder is configured to apply different scaling values for different context models.

28. The arithmetic encoder according to one of claims 1 to 27, wherein the arithmetic encoder is configured to update a first state variable value (sk0) in dependence on a symbol to be encoded; wherein the arithmetic encoder is configured to derive a second state variable value (sk1) on the basis of the first state variable value for a first group of bins following an initialization of the two or more state variable values, and wherein the arithmetic encoder is configured to update the second state variable value (sk1) in dependence on a symbol to be encoded for a second group of bins following the first group of bins FH240412PEP-2025112831.DOCX29. An arithmetic encoder (34;400) for encoding a plurality of symbols (24’’, 410) having symbol values , wherein the arithmetic encoder is configured to determine a plurality of state variable values (s0k, s1k; 642,644; 710;810;910;1010a,1010b;1082a,1082b;1110;1210;1310; 1410;1510;1632,1642;1732,1742,1812,1820,1912,1914,1922,1924,2010), which represent statistics of a plurality of previously encoded symbol values, and wherein the arithmetic encoder is configured to derive an interval size information (pk, R*pk, rangeLPS; 432;534;620;720;820;820;1020;1084;1120;1320;1420;1520;1662;1762,2020) for an arithmetic encoding of one or more symbol values to be encoded on the basis of the two or more state variable values (sik), which represent statistics of a plurality of previously encoded symbol values, wherein the arithmetic encoder is configured to update a first state variable value (sk0, 1912, 1922) in dependence on a symbol to be encoded; wherein the arithmetic encoder is configured to derive a second state variable value (sk1, 1914, 1924) on the basis of the first state variable value for a first group of bins following an initialization of the one or more state variable values, and wherein the arithmetic encoder is configured to update the second state variable value (sk1) in dependence on a symbol to be encoded for a second group of bins following the first group of bins.

30. The arithmetic encoder according to claim 29, wherein the arithmetic encoder is configured to scale the first state variable value, in order to derive the second state variable value from the first state variable value for a first group of bins following an initialization of the one or more state variable values .

31. The arithmetic encoder according to claim 29 or 30, wherein the arithmetic encoder is configured update the first state variable value and the second state variable value using different adaptation time constants for the second group of bins. FH240412PEP-2025112831.DOCX32. The arithmetic encoder according to one of claims 29 to 31, wherein the arithmetic encoder is configured to update the second state variable value with a longer adaptation time constant than the first state variable value for the second group of bins.

33. The arithmetic encoder according to one of claims 29 to 32, wherein the arithmetic encoder is configured to scale the first state variable value with a scaling value which is a potency of two for the first group of bins, in order to obtain the second state variable value 34. The arithmetic encoder according to one of claims 29 to 33, wherein the arithmetic encoder is configured to obtain the second state variable value s1kon the basis of the first state variable value s0kaccording tofor the first group of bins; wherein stateBits1is a number of bits used for a representation of the second state variable value, and wherein stateBits0 is a number of bits used for a representation of the first state variable value.

35. The arithmetic encoder according to one of claims 29 to 34, wherein the arithmetic encoder is configured to combine the first state variable value and the second state variable value using a weighted summation, in order to obtain a combined state variable value, and wherein the arithmetic encoder is configured to derive the interval size information in dependence on the combined state variable values.

36. The arithmetic encoder according to one of claims 29 to 35, wherein the arithmetic encoder is configured to obtain a combined state variable value sk according toFH240412PEP-2025112831.DOCXwherein s0kis the first state variable value; wherein s1kis the second state variable value; wherein stateBits0is a number of bits used to represent the first state variable value; wherein stateBits1is a number of bits used to represent the second state variable value; and wherein ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ = 1 + ^^^^^^(^^^^^^^^^^^^^^^^^^0, ^^^^^^^^^^^^^^^^^^1);wherein max(.) is a maximum operator. FH240412PEP-2025112831.DOCX37. An arithmetic encoder (34;400) for encoding a plurality of symbols (24’’, 410) having symbol values , wherein the arithmetic encoder is configured to derive an interval size value (rangeLPS; RLPS; 432;534;620;720;820;820;1020;1084;1120;1320;1420;1520;1662;1762,2020) for an arithmetic encoding of one or more symbol values to be encoded on the basis of one or more state variable values (sik; 642,644; 710;810;910;1010a,1010b;1082a,1082b;1110; 1210;1310;1410;1510;1632,1642;1732,1742,1812,1820,1912,1914,1922,1924,2010), which represent statistics of a plurality of previously encoded symbol values, wherein the arithmetic encoder is configured to determine the interval size value (rangeLPS,2020) using a probability table (ProbLPSMapping[],2050), which represents probability values in an integer representation, wherein the arithmetic encoder is configured to select an entry of the probability table in dependence on the one or more state variable values, and wherein the arithmetic encoder is configured to determine the interval size value in dependence on the selected entry; wherein the probability table represents a probability of 0.5 using a table value 2probPrec-1, and wherein the probability table represents other probability values probExact using table values which are equal to probExact*2probPrec+1except for a rounding effect; wherein probPrec is a number of bits used to represent respective entries of the probability table.

38. The arithmetic encoder according to claim 37, wherein the probability table represents probability values probExact(i) according to ^^^^^^^^^^^^^^^^^^ = 0.5 ∙ ^^^^∙^^^^^^^^^^^^^^^^using table entries FH240412PEP-2025112831.DOCX^^^^^^^^^^^^^^^^^^^^^^^^^^^^[^^] = max(1, min( (1 << ^^^^^^^^^^^^^^^^) − 1, ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^),wherein^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ = round (^^^^^^^^^^^^^^^^^^ ∙ 2^^^^^^^^^^^^^^^^+1)wherein exponent is a predetermined values wherein i is a table entry index between 0 and a predetermined maximum value; wherein α is a constant, probPrec is the number of bits used to represent respective entries of the probability table; wherein min(.) is a minimum operator; wherein max (.) is a maximum operator; wherein << is a bit shift operator; wherein round (.) is a rounding operation.

39. The arithmetic encoder according to claim 37 or 38, wherein in the probability table a table entry representing a probability of 0.5 is clipped down to 2probPrec-1.

41. The arithmetic encoder according to one of claims 37 to 39, wherein the probability table takes the form ProbLPSmapping[]= [2047,2014,1980,1946,1914,1882,1850,1819,1788,1758,1729,1700,1671,1643, 1615,1588,1561,1535,1509,1484,1459,1434,1410,1387,1363,1340,1318,1296, 1274,1252,1231,1211,1190,1170,1151,1131,1112,1094,1075,1057,1039,1022, 1005,988,971,955,939,923,908,892,877,863,848,834,820,806,792,779,766,753, 740,728,716,704,692,680,669,658,647,636,625,614,604,594,584,574,564, 555,546,537,527,519,510,501,493,485,476,468,461,453,445,438,430,423, 416,409,402,395,389,382,376,369,363,357,351,345,339,334,328,323,317, FH240412PEP-2025112831.DOCX312,307,301,296,291,286,282,277,272,268,263,259,254,250,246,242,238, 234,230,226,222,218,215,211,208,204,201,197,194,191,187,184,181, 178,175,172,169,167,164,161,158,156,153,150,148,145,143,141,138, 136,134,131,129,127,125,123,121,119,117,115,113,111,109,107,105, 104,102 100, 98, 97, 95, 94, 92, 90, 89, 87, 86, 85, 83, 82, 80, 79, 78, 76, 75, 74, 73, 71, 70, 69, 68, 67, 66, 64, 63, 62, 61, 60, 59, 58, 57, 56, 55, 54, 53, 53, 52, 51, 50, 49, 48, 47, 47, 46, 45, 44, 44, 43, 42, 41, 41, 40, 39, 39, 38, 37, 37, 36, 36, 35, 34, 34, 33, 33, 32, 32, 31, 31, 30, 30, 29, 29, 28, 28, 27].

41. The arithmetic encoder according to one of claims 37 to 40, wherein the arithmetic encoder is configured to determine the interval size value in dependence on a coding interval size (range; R;434;532;712;812;1362;1460;1512), and wherein the arithmetic encoder is configured to perform the arithmetic encoding of one or more symbols using the interval size value (RLPS).

42. The arithmetic encoder according to one of claims 37 to 41, wherein the arithmetic encoder is configured to multiply an element of the probability table (Prob_TabLPS) with a coding interval size, in order to obtain the interval size value (rangeLPS).

43. The arithmetic encoder according to one of claims 37 to 42, wherein the arithmetic encoder is configured to apply a bit shift operation discarding one or more least significant bits to a product between a selected element of the probability table and a coding interval size, in order to obtain the interval size value (rangeLPS).

44. The arithmetic encoder according to one of claims 37 to 43, wherein the arithmetic encoder is configured to obtain a combined state variable value, and wherein the arithmetic encoder is configured to select an entry of the probability table in dependence on the combined state variable value.

45. The arithmetic encoder according to one of claims 37 to 44, wherein the arithmetic encoder is configured to obtain a selected entry probLPSint of the probability table ProbLPSmapping according to FH240412PEP-2025112831.DOCX^^^^^^^^^^^^^^^^^^^^ = ProbLPSmapping[abs(^^^^ >> (stateBitsCombined − probLPSbits − 1))]wherein sk is a combined state variable value; wherein abs (.) is an absolute value operator; wherein >> is a bit-shift-to-the-right operator; wherein stateBitsCombined is a number of bits necessary to represent skas signed integer in 2’s complement representation.

46. The arithmetic encoder according to one of claims 37 to 45,wherein the arithmetic decoder is configured to obtain an interval size value rangeLPS usingrangeLPS = (^^^^^^^^^^ ∙ ^^^^^^^^^^^^^^^^^^^^) >> (^^^^^^^^^^^^^^^^ + 1)or using rangeLPS = (^^^^^^^^^^ ∙ ^^^^^^^^^^^^^^^^^^^^ + (1 << ^^^^^^^^^^^^^^^^)) >> (^^^^^^^^^^^^^^^^ + 1)wherein range is a coding interval size, wherein probLPSint is an entry of the probability table, wherein probPrec is a number of bits necessary to store elements of the probability table as unsigned integers.

47. The arithmetic encoder according to one of claims 37 to 46, wherein the arithmetic encoder is configured to enforce that the interval size value is larger than zero.

48. The arithmetic encoder according to one of claims 37 to 47, wherein the arithmetic encoder is configured to determine the one or more state variable values and / or the combined state variable value according to one of claims 1 to 37. FH240412PEP-2025112831.DOCX49. An arithmetic decoder (34;400) for decoding a plurality of symbols (24’’, 410) having symbol values , wherein the arithmetic decoder is configured to determine one or more state variable values (s0k, s1k, s2k; 642,644; 710;810;910;1010a,1010b;1082a,1082b;1110;1210;1310; 1410;1510;1632,1642;1732,1742,1820,1922,1924,2010), which represent statistics of a plurality of previously decoded symbol values, and wherein the arithmetic decoder is configured to derive an interval size information (pk, R*pk;,rangeLPS; 432;534;620;720;820;820;1020;1084;1120;1320;1420;1520;1662;1762,2020) for an arithmetic decoding of one or more symbol values to be decoded on the basis of one or more state variable values which represent statistics of a plurality of previously decoded symbol values wherein the arithmetic decoder is configured to selectively increase an adaptation speed of one or more of the state variable values for a predetermined number of bins following an initialization of the one or more state variable values; and / or wherein the arithmetic decoder is configured to selectively reduce an adaptation speed of one or more of the state variable values when a predetermined number of bins following an initialization of one or more state variable values has passed; and / or wherein the arithmetic decoder is configured to use a first, comparatively higher adaptation speed for adapting one or more of the state variable values to a probability of decoded symbol values for a first group of bins following an initialization of the one or more state variable values, and to use a second, comparatively lower adaptation speed for adapting one or more of the state variable values to a probability of decoded symbol values for a second group of bins following the first group of bins.

50. The arithmetic decoder according to claim 49, wherein the arithmetic decoder is configured to selectively modify a scaling value, which adjusts a magnitude of a change of one or more of the state variable values, which occurs in response to an decoded symbol, in dependence on a counting of bins processed since an initialization of the one or more state variable values. FH240412PEP-2025112831.DOCX51. The arithmetic decoder according to claim 49 or 50, wherein the arithmetic decoder is configured to determine an increment value, by which one or more of the state variable values are incremented in case that a symbol to be decoded takes a first symbol value, in dependence on a scaling value; wherein the arithmetic decoder is configured to determine a decrement value, by which one or more of the state variable values are decremented in case that a symbol to be decoded takes a second symbol value, in dependence on the scaling value; and wherein the arithmetic decoder is configured to gradually or step-wisely reduce the scaling value in dependence on a number of bins processed since an initialization of the one or more state variable values.

52. The arithmetic decoder according to one of claims 49 to 51, wherein the arithmetic decoder is configured to set the scaling value to a first value for a first plurality of bins following an initialization of the one or more state variable values, and wherein the arithmetic decoder is configured to set the scaling value to a second value, which is smaller than the first value, for a second plurality of bins following the first plurality of bins.

53. The arithmetic decoder according to one of claims 49 to 52, wherein the arithmetic decoder is configured to update a first state variable value (sk1) in dependence on a symbol to be decoded and using a look-up table (A); wherein the arithmetic decoder is configured to scale a table value obtained using the look- up table using a scaling value, in order to obtain an increment value by which the first state variable value is incremented or a decrement value by which the first state variable value is decremented.

54. The arithmetic decoder according to one of claims 49 to 53, wherein the arithmetic decoder is configured to update a second state variable value (sk2) in dependence on a symbol to be decoded and using a look-up table (A); wherein the arithmetic decoder is configured to scale a table value obtained using the look- up table using a scaling value, in order to obtain an increment value by which the second FH240412PEP-2025112831.DOCXstate variable value is incremented or a decrement value by which the second state variable value is decremented.

55. The arithmetic decoder according to one of claims 49 to 54, wherein the arithmetic decoder is configured update the first state variable value and the second state variable value using different adaptation time constants at least for the second group of bins.

56. The arithmetic decoder according to one of claims 49 to 55, wherein the arithmetic decoder is configured to selectively increase or decrease a previous state variable value by a value determined using the look-up table in dependence on whether a symbol to be decoded takes a first value or a second value which is different from the first value.

57. The arithmetic decoder according to one of claims 49 to 56, wherein a magnitude of the increase or decrease is dependent on a number of bins processed since an initialization of the one or more state variable values.

58. The arithmetic decoder according to one of claims 49 to 57, wherein the arithmetic decoder is configured to increase a previous state variable value by a comparatively larger value in case that the previous state variable value is negative when compared to a case that the previous state variable value is positive if a symbol to be decoded takes a first value; and wherein the arithmetic decoder is configured to decrease a previous state variable value by a comparatively larger value in case that the previous state variable value is positive when compared to a case that the previous state variable value is negative if a symbol to be decoded takes a second value which is different from the first value.

59. The arithmetic decoder according to one of claims 49 to 58, wherein the arithmetic decoder is configured to determine an index of an entry of the lookup table to be evaluated when updating the first state variable value in dependence on a sum of a predetermined offset value (z) and a previously computed first state variable value ( ^^1^^), or a scaled and / or rounded version ( ⌊) thereof, if a symbol to be decoded takes a first value; and FH240412PEP-2025112831.DOCXwherein the arithmetic decoder is configured to determine an index of an entry of the lookup table to be evaluated when updating the first state variable value in dependence on a sum of a predetermined offset value (z) and a in inversed version ( −^^1^^) of a previously computed first state variable value, or a scaled and / or rounded versionthereof, if a symbol to be decoded takes a second value.

60. The arithmetic decoder according to one of claims 49 to 59, wherein the arithmetic decoder is configured to determine an index of an entry of the lookup table to be evaluated when updating the second state variable value in dependence on a sum of a predetermined offset value (z) and a previously computed second state variable value ( ^^2^^), or a scaled and / or rounded version thereof, if a symbol to be decoded takes a first value; and wherein the arithmetic decoder is configured to determine an index of an entry of the lookup table to be evaluated when updating the second state variable value in dependence on a sum of a predetermined offset value (z) and a in inversed version ( −^^2^^) of a previously computed second state variable value, or a scaled and / or rounded version thereof, if a symbol to be decoded takes a second value.

61. The arithmetic decoder according to one of claims 49 to 60, wherein the arithmetic decoder is configured to apply a first scaling value (mk1), to scale the previously computed first state variable value (sk1), when determining an index of an entry of the lookup table to be evaluated when updating the first state variable value, and wherein the arithmetic decoder is configured to apply a second scaling value (mk2), to scale the previously computed second state variable value (sk2), when determining an index of an entry of the lookup table to be evaluated when updating the second state variable value, wherein the first scaling value is different from the second scaling value.

62. The arithmetic decoder according to one of claims 49 to 61, wherein the arithmetic decoder is configured to scale a value returned by an evaluation of the lookup table using a first scaling value when updating the first state variable value, FH240412PEP-2025112831.DOCXwherein the arithmetic decoder is configured to scale a value returned by an evaluation of the lookup table using a second scaling value when updating the second state variable value, wherein the first scaling value is different from the second scaling value.

63. The arithmetic decoder according to one of claims 49 to 62, wherein the arithmetic decoder is configured to determine one or more updated state variable values ^^^^^^according towherein A is a lookup table, wherein z is a predetermined offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^are one or more weighting values.

64. The arithmetic decoder according to one of claims 49 to 63, wherein a number of state variables is equal to 2;wherein ^^ = {157, 143, 129, 115, 101, 87, 73, 59, 45, 35, 29, 23, 17, 13, 9, 5,4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 0};wherein z=16; wherein ^^^^^^^^^^^^^^^^^^^^is a number of bits sufficient to represent state ^^^^^^as a signed integer in 2's complement representation; wherein ^^^^ 5−^^^^^^^^^^^^^^^^^^ = 2 ^^^^;wherein ^^^^^^^^^^^^^^^^^^^^^^is an adaptation rate parameter associated with state variable ^^^^^^; wherein65. The arithmetic decoder according to one of claims 49 to 64, wherein the arithmetic decoder is configured to initialize a counter with a predetermined value before decoding a first bin associated with a given context model; and FH240412PEP-2025112831.DOCXwherein the arithmetic decoder is configured to update the counter after decoding a respective bin associated with the given context model.

66. The arithmetic decoder according to one of claims 49 to 65, wherein countInit=63;wherein ^^^^^^^^^^^^^^^^^^0 = 10;wherein ^^^^^^^^^^^^^^^^^^1 = 13;67. The arithmetic decoder according to one of claims 49 to 66, wherein the arithmetic decoder is configured to determine one or more updated state variable values ^^^^^^according towherein A is a lookup table, wherein z is a predetermined offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^are one or more weighting values.

68. The arithmetic decoder according to one of claims 49 to 67, wherein the arithmetic decoder is configured to determine one or more updated state variable values ^^^^^^according towherein A is a lookup table, FH240412PEP-2025112831.DOCXwherein z is a predetermined offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^are one or more weighting values.

69. The arithmetic decoder according to one of claims 49 to 68, wherein the arithmetic decoder is configured to determine one or more updated state variable values ^^^^^^according towherein A is a lookup table, wherein z is a predetermined offset value; wherein ^^^^^^are one or more weighting values; wherein ^^^^^^are one or more weighting values.

70. The arithmetic decoder according to one of claims 49 to 69, wherein the entries of A decrease monotonically with increasing lookup table index.

71. The arithmetic decoder according to one of claims 49 to 70, wherein A isor deviates therefrom merely for one or more extreme values of its argument by zero setting or magnitude reduction to avoid the updated ^^^^^^leaving a predetermined value range, where ^^^^^^^^^^^^, ^̂^, ^̂^^^, and ^̂^^^are predetermined parameters.

72. The arithmetic decoder according to one of claims 49 to 71, wherein a last entry of the lookup table is equal to zero. FH240412PEP-2025112831.DOCX73. The arithmetic decoder according to one of claims 49 to 72, wherein the arithmetic decoder is configured to apply a clipping operation to the updated state variable values, to keep the updated and clipped state variable values within a predetermined range of values.

74. The arithmetic decoder according to one of claims 49 to 73, wherein the arithmetic decoder is configured to apply a clipping operation according to ^^^^^^ = ^^^^^^(^^^^^^(^^ ^^^^ , ℎ ^^^^ ), ^^^^^^) to the updated state variable values, wherein ^^^^^^is a maximum allowed value for ^^^^^^, and wherein ℎ^^^^is a minimum allowed value for ^^^^^^.

75. The arithmetic decoder according to one of claims 49 to 74, wherein the arithmetic decoder is configured to apply different scaling values for different context models.

76. The arithmetic decoder according to one of claims 49 to 75, wherein the arithmetic decoder is configured to update a first state variable value (sk0) in dependence on a symbol to be decoded; wherein the arithmetic decoder is configured to derive a second state variable value (sk1) on the basis of the first state variable value for a first group of bins following an initialization of the two or more state variable values, and wherein the arithmetic decoder is configured to update the second state variable value (sk1) in dependence on a symbol to be decoded for a second group of bins following the first group of bins. FH240412PEP-2025112831.DOCX77. An arithmetic decoder (34;400) for decoding a plurality of symbols (24’’, 410) having symbol values , wherein the arithmetic decoder is configured to determine a plurality of state variable values (s0k, s1k; 642,644; 710;810;910;1010a,1010b;1082a,1082b;1110;1210;1310; 1410;1510;1632,1642;1732,1742,1820,1922,1924,2010), which represent statistics of a plurality of previously decoded symbol values, and wherein the arithmetic decoder is configured to derive an interval size information (pk, R*pk,rangeLPS; 432;534;620;720;820;820;1020;1084;1120;1320;1420;1520;1662;1762,2020) for an arithmetic decoding of one or more symbol values to be decoded on the basis of the two or more state variable values (sik), which represent statistics of a plurality of previously decoded symbol values, wherein the arithmetic decoder is configured to update a first state variable value (sk0, 1912, 1922) in dependence on a symbol to be decoded; wherein the arithmetic decoder is configured to derive a second state variable value (sk1, 1924) on the basis of the first state variable value (sk0, 1912, 1922) for a first group of bins following an initialization of the one or more state variable values, and wherein the arithmetic decoder is configured to update the second state variable value (sk1, 1914, 1924) in dependence on a symbol to be decoded for a second group of bins following the first group of bins.

78. The arithmetic decoder according to claim 77, wherein the arithmetic decoder is configured to scale the first state variable value, in order to derive the second state variable value from the first state variable value for a first group of bins following an initialization of the one or more state variable values.

79. The arithmetic decoder according to claim 77 or 78, wherein the arithmetic decoder is configured update the first state variable value and the second state variable value using different adaptation time constants for the second group of bins. FH240412PEP-2025112831.DOCX80. The arithmetic decoder according to one of claims 77 to 79, wherein the arithmetic decoder is configured to update the second state variable value with a longer adaptation time constant than the first state variable value for the second group of bins.

81. The arithmetic decoder according to one of claims 77 to 80, wherein the arithmetic decoder is configured to scale the first state variable value with a scaling value which is a potency of two for the first group of bins, in order to obtain the second state variable value.

82. The arithmetic decoder according to one of claims 77 to 81, wherein the arithmetic decoder is configured to obtain the second state variable value s1kon the basis of the first state variable value s0kaccording tofor the first group of bins; wherein stateBits1is a number of bits used for a representation of the second state variable value, and wherein stateBits0 is a number of bits used for a representation of the first state variable value.

83. The arithmetic decoder according to one of claims 77 to 82, wherein the arithmetic decoder is configured to combine the first state variable value and the second state variable value using a weighted summation, in order to obtain a combined state variable value , and wherein the arithmetic decoder is configured to derive the interval size information in dependence on the combined state variable values.

84. The arithmetic decoder according to one of claims 77 to 83, wherein the arithmetic decoder is configured to obtain a combined state variable value sk according toFH240412PEP-2025112831.DOCXwherein s0kis the first state variable value; wherein s1kis the second state variable value; wherein stateBits0is a number of bits used to represent the first state variable value; wherein stateBits1is a number of bits used to represent the second state variable value; and wherein ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ = 1 + ^^^^^^(^^^^^^^^^^^^^^^^^^0, ^^^^^^^^^^^^^^^^^^1);wherein max(.) is a maximum operator. FH240412PEP-2025112831.DOCX85. An arithmetic decoder (34;400) for decoding a plurality of symbols (24’’, 410) having symbol values , wherein the arithmetic decoder is configured to derive an interval size value (rangeLPS; RLPS; 432;534;620;720;820;820;1020;1084;1120;1320;1420;1520;1662;1762,2020) for an arithmetic decoding of one or more symbol values to be decoded on the basis of one or more state variable values (sik; 642,644; 710;810;910;1010a,1010b;1082a,1082b;1110; 1210;1310;1410;1510;1632,1642;1732,1742,1820,1922,1924,2010), which represent statistics of a plurality of previously decoded symbol values, wherein the arithmetic decoder is configured to determine the interval size value (rangeLPS,2020) using a probability table (ProbLPSMapping[],2050), which represents probability values in an integer representation, wherein the arithmetic decoder is configured to select an entry of the probability table in dependence on the one or more state variable values (sik, 1820,1922,1924,2010), and wherein the arithmetic decoder is configured to determine the interval size value in dependence on the selected entry; wherein the probability table represents a probability of 0.5 using a table value 2probPrec-1, and wherein the probability table represents other probability values probExact using table values which are equal to probExact*2probPrec+1except for a rounding effect; wherein probPrec is a number of bits used to represent respective entries of the probability table.

86. The arithmetic decoder according to claim 85, wherein the probability table represents probability values probExact(i) according to ^^^^^^^^^^^^^^^^^^ = 0.5 ∙ ^^^^∙^^^^^^^^^^^^^^^^using table entries FH240412PEP-2025112831.DOCX^^^^^^^^^^^^^^^^^^^^^^^^^^^^[^^] = max(1, min( (1 << ^^^^^^^^^^^^^^^^) − 1, ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^),wherein^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ = round (^^^^^^^^^^^^^^^^^^ ∙ 2^^^^^^^^^^^^^^^^+1)wherein exponent is a predetermined values wherein i is a table entry index between 0 and a predetermined maximum value; wherein α is a constant, probPrec is the number of bits used to represent respective entries of the probability table; wherein min(.) is a minimum operator; wherein max (.) is a maximum operator; wherein << is a bit shift operator; wherein round (.) is a rounding operation.

87. The arithmetic decoder according to claim 85 or 86, wherein in the probability table a table entry representing a probability of 0.5 is clipped down to 2probPrec-1.

88. The arithmetic decoder according to one of claims 85 to 87, wherein the probability table takes the form ProbLPSmapping[]=[2047,2014,1980,1946,1914,1882,1850,1819,1788,1758,1729,1700,1 671,1643, 1615,1588,1561,1535,1509,1484,1459,1434,1410,1387,1363,1340,1318,1296, 1274,1252,1231,1211,1190,1170,1151,1131,1112,1094,1075,1057,1039,1022, 1005,988,971,955,939,923,908,892,877,863,848,834,820,806,792,779,766,753, 740,728,716,704,692,680,669,658,647,636,625,614,604,594,584,574,564, 555,546,537,527,519,510,501,493,485,476,468,461,453,445,438,430,423, 416,409,402,395,389,382,376,369,363,357,351,345,339,334,328,323,317, FH240412PEP-2025112831.DOCX312,307,301,296,291,286,282,277,272,268,263,259,254,250,246,242,238, 234,230,226,222,218,215,211,208,204,201,197,194,191,187,184,181, 178,175,172,169,167,164,161,158,156,153,150,148,145,143,141,138, 136,134,131,129,127,125,123,121,119,117,115,113,111,109,107,105, 104,102 100, 98, 97, 95, 94, 92, 90, 89, 87, 86, 85, 83, 82, 80, 79, 78, 76, 75, 74, 73, 71, 70, 69, 68, 67, 66, 64, 63, 62, 61, 60, 59, 58, 57, 56, 55, 54, 53, 53, 52, 51, 50, 49, 48, 47, 47, 46, 45, 44, 44, 43, 42, 41, 41, 40, 39, 39, 38, 37, 37, 36, 36, 35, 34, 34, 33, 33, 32, 32, 31, 31, 30, 30, 29, 29, 28, 28, 27].

89. The arithmetic decoder according to one of claims 85 to 78, wherein the arithmetic decoder is configured to determine the interval size value in dependence on a coding interval size (range; R;434;532;712;812;1362;1460;1512), and wherein the arithmetic decoder is configured to perform the arithmetic decoding of one or more symbols using the interval size value (RLPS).

90. The arithmetic decoder according to one of claims 85 to 89, wherein the arithmetic decoder is configured to multiply an element of the probability table (Prob_TabLPS) with a coding interval size, in order to obtain the interval size value (rangeLPS).

91. The arithmetic decoder according to one of claims 85 to 90, wherein the arithmetic decoder is configured to apply a bit shift operation discarding one or more least significant bits to a product between a selected element of the probability table and a coding interval size, in order to obtain the interval size value (rangeLPS).

92. The arithmetic decoder according to one of claims 85 to 91, wherein the arithmetic decoder is configured to obtain a combined state variable value, and wherein the arithmetic decoder is configured to select an entry of the probability table in dependence on the combined state variable value.

93. The arithmetic decoder according to one of claims 85 to 92, wherein the arithmetic decoder is configured to obtain a selected entry probLPSint of the probability table ProbLPSmapping according to FH240412PEP-2025112831.DOCX^^^^^^^^^^^^^^^^^^^^ = ProbLPSmapping[abs(^^^^ >> (stateBitsCombined − probLPSbits − 1))]wherein sk is a combined state variable value; wherein abs (.) is an absolute value operator; wherien >> is a bit-shift-to-the-right operator; wherein stateBitsCombined is a number of bits necessary to represent skas signed integer in 2’s complement representation.

94. The arithmetic decoder according to one of claims 85 to 93, wherein the arithmetic decoder is configured to obtain an interval size value rangeLPS usingrangeLPS = (^^^^^^^^^^ ∙ ^^^^^^^^^^^^^^^^^^^^) >> (^^^^^^^^^^^^^^^^ + 1)or using rangeLPS = (^^^^^^^^^^ ∙ ^^^^^^^^^^^^^^^^^^^^ + (1 << ^^^^^^^^^^^^^^^^)) >> (^^^^^^^^^^^^^^^^ + 1)wherein range is a coding interval size, wherein probLPSint is an entry of the probability table, wherein probPrec is a number of bits necessary to store elements of the probability table as unsigned integers.

95. The arithmetic decoder according to one of claims 85 to 93, wherein the arithmetic decoder is configured to enforce that the interval size value is larger than zero.

96. The arithmetic decoder according to one of claims 85 to 94, wherein the arithmetic decoder is configured to determine the one or more state variable values and / or the combined state variable value according to one of claims 49 to 84. FH240412PEP-2025112831.DOCX97. Method for encoding a plurality of symbols (24’’, 410) having symbol values , wherein the method comprises determining one or more state variable values (s1k, s2k; 642,644; 710;810;910;1010a,1010b;1082a,1082b;1110;1210;1310; 1410;1510;1632,1642;1732,1742,1820,1922,1924,2010), which represent statistics of a plurality of previously encoded symbol values, and wherein the method comprises deriving an interval size information (pk, R*pk;,rangeLPS; 432;534;620;720;820;820;1020;1084;1120;1320;1420;1520;1662;1762,2020) for an arithmetic encoding of one or more symbol values to be encoded on the basis of one or more state variable values which represent statistics of a plurality of previously encoded symbol values wherein the method comprises selectively increasing an adaptation speed of one or more of the state variable values for a predetermined number of bins following an initialization of the one or more state variable values; and / or wherein the method comprises selectively reducing an adaptation speed of one or more of the state variable values when a predetermined number of bins following an initialization of one or more state variable values has passed; and / or wherein the method comprises using a first, comparatively higher adaptation speed for adapting one or more of the state variable values to a probability of encoded symbol values for a first group of bins following an initialization of the one or more state variable values, and to use a second, comparatively lower adaptation speed for adapting one or more of the state variable values to a probability of encoded symbol values for a second group of bins following the first group of bins.

98. Method for encoding a plurality of symbols (24’’, 410) having symbol values, wherein the method comprises determining a plurality of state variable values (s0k, s1k; 642,644; 710;810;910;1010a,1010b;1082a,1082b;1110;1210;1310; 1410;1510;1632,1642;1732,1742,1820,1922,1924,2010), which represent statistics of a plurality of previously encoded symbol values, and FH240412PEP-2025112831.DOCXwherein the method comprises deriving an interval size information (pk, R*pk,rangeLPS; 432;534;620;720;820;820;1020;1084;1120;1320;1420;1520;1662;1762,2020) for an arithmetic encoding of one or more symbol values to be encoded on the basis of the two or more state variable values (sik), which represent statistics of a plurality of previously encoded symbol values, wherein the method comprises updating a first state variable value (sk0) in dependence on a symbol to be encoded; wherein the method comprises deriving a second state variable value (sk1) on the basis of the first state variable value for a first group of bins following an initialization of the one or more state variable values, and wherein the method comprises updating the second state variable value (sk1) in dependence on a symbol to be encoded for a second group of bins following the first group of bins.

99. Method for encoding a plurality of symbols (24’’, 410) having symbol values, wherein the method comprises deriving an interval size value (rangeLPS; RLPS; 432;534;620;720;820;820;1020;1084;1120;1320;1420;1520;1662;1762) for an arithmetic encoding of one or more symbol values to be encoded on the basis of one or more state variable values (sik; 642,644; 710;810;910;1010a,1010b;1082a,1082b;1110; 1210;1310;1410;1510;1632,1642;1732,1742,1820,1922,1924,2010), which represent statistics of a plurality of previously encoded symbol values, wherein the method comprises determining the interval size value (rangeLPS,2020) using a probability table (ProbLPSMapping[],2050), which represents probability values in an integer representation, wherein the method comprises selecting an entry of the probability table in dependence on the one or more state variable values, and wherein the method comprises determining the interval size value in dependence on the selected entry; FH240412PEP-2025112831.DOCXwherein the probability table represents a probability of 0.5 using a table value 2probPrec-1, and wherein the probability table represents other probability values probExact using table values which are equal to probExact*2probPrec+1except for a rounding effect; wherein probPrec is a number of bits used to represent respective entries of the probability table.

100. Method for decoding a plurality of symbols (24’’, 410) having symbol values , wherein the method comprises determining one or more state variable values (s1k, s2k; 642,644; 710;810;910;1010a,1010b;1082a,1082b;1110;1210;1310; 1410;1510;1632,1642;1732,1742,1820,1922,1924,2010), which represent statistics of a plurality of previously decoded symbol values, and wherein the method comprises deriving an interval size information (pk, R*pk;,rangeLPS; 432;534;620;720;820;820;1020;1084;1120;1320;1420;1520;1662;1762,2020) for an arithmetic decoding of one or more symbol values to be decoded on the basis of one or more state variable values which represent statistics of a plurality of previously decoded symbol values wherein the method comprises selectively increasing an adaptation speed of one or more of the state variable values for a predetermined number of bins following an initialization of the one or more state variable values; and / or wherein the method comprises selectively reducing an adaptation speed of one or more of the state variable values when a predetermined number of bins following an initialization of one or more state variable values has passed; and / or wherein the method comprises using a first, comparatively higher adaptation speed for adapting one or more of the state variable values to a probability of decoded symbol values for a first group of bins following an initialization of the one or more state variable values, and to use a second, comparatively lower adaptation speed for adapting one or more of the state variable values to a probability of decoded symbol values for a second group of bins following the first group of bins. FH240412PEP-2025112831.DOCX101. Method for decoding a plurality of symbols (24’’, 410) having symbol values, wherein the method comprises determining a plurality of state variable values (s0k, s1k; 642,644; 710;810;910;1010a,1010b;1082a,1082b;1110;1210;1310; 1410;1510;1632,1642;1732,1742,1820,1922,1924,2010), which represent statistics of a plurality of previously decoded symbol values, and wherein the method comprises deriving an interval size information (pk, R*pk,rangeLPS; 432;534;620;720;820;820;1020;1084;1120;1320;1420;1520;1662;1762,2020) for an arithmetic decoding of one or more symbol values to be decoded on the basis of the two or more state variable values (sik), which represent statistics of a plurality of previously decoded symbol values, wherein the method comprises updating a first state variable value (sk0) in dependence on a symbol to be decoded; wherein the method comprises deriving a second state variable value (sk1) on the basis of the first state variable value for a first group of bins following an initialization of the one or more state variable values, and wherein the method comprises updating the second state variable value (sk1) in dependence on a symbol to be decoded for a second group of bins following the first group of bins.

102. Method for decoding a plurality of symbols (24’’, 410) having symbol values, wherein the method comprises deriving an interval size value (rangeLPS; RLPS; 432;534;620;720;820;820;1020;1084;1120;1320;1420;1520;1662;1762,2020) for an arithmetic decoding of one or more symbol values to be decoded on the basis of one or more state variable values (sik; 642,644; 710;810;910;1010a,1010b;1082a,1082b;1110; 1210;1310;1410;1510;1632,1642;1732,1742,1820,1922,1924,2010), which represent statistics of a plurality of previously decoded symbol values, wherein the method comprises determining the interval size value (rangeLPS,2020) using a probability table (ProbLPSMapping[],2050s), which represents probability values in an integer representation, FH240412PEP-2025112831.DOCXwherein the method comprises selecting an entry of the probability table in dependence on the one or more state variable values, and wherein the method comprises determining the interval size value in dependence on the selected entry; wherein the probability table represents a probability of 0.5 using a table value 2probPrec-1, and wherein the probability table represents other probability values probExact using table values which are equal to probExact*2probPrec+1except for a rounding effect; wherein probPrec is a number of bits used to represent respective entries of the probability table.

103. A computer program for performing the method according to one of claims 97 to 102, when the computer program runs on a computer. FH240412PEP-2025112831.DOCX

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