CHROMA SHIFT PRESENCE SIGNAL IN VIDEO ENCODING

Abstract

A video coding system that handles at least one block of at least one image of a video comprises an encoding process and a decoding process that provide or use respectively video-related signaling information, wherein the signaling information comprises at least information representing the presence of chroma shift values, wherein when chroma is present and does not use separate color planes, the information representing the presence of chroma shift values ​​is established and the signaling information further comprises information representing chroma shift values, and wherein when chroma is not present or uses separate color planes, the information representing the presence of chroma shift values ​​is reset, and no further information representing chroma shift values ​​is signaled.

Description

CHROMA SHIFT PRESENCE SIGNALING IN VIDEO ENCODING Rwn Ln / zznz / E / YiAi FIELD OF INVENTION At least one of the present modalities generally relates to signaling syntax for video encoding and decoding and more particularly to chroma shift values. BACKGROUND OF THE INVENTION To achieve high compression efficiency, image and video coding schemes typically use prediction and transform to leverage spatial and temporal redundancy in the video content. Generally, intraprediction or interprediction is used to exploit intra- or inter-frame correlation. The differences between the original and predicted blocks, often referred to as prediction errors or prediction residuals, are then transformed, quantized, and encoded by entropy. To reconstruct the video, the compressed data is decoded using the reverse processes of entropy coding, quantization, transformation, and prediction. SUMMARY OF THE INVENTION One or more of the present modalities provides a video encoding system that handles at least one block Ref.337254 of at least one image of a video comprising an encoding process and a decoding process respectively implemented in an encoding apparatus and a decoding apparatus, which provide or use respectively video-related signaling information, wherein the signaling information comprises at least information representing the presence of chroma shift values, wherein when chroma is present and does not use separate color planes, the information representing the presence of chroma shift values ​​is established and the signaling information further comprises information representing chroma shift values ​​and wherein when chroma is not present or uses separate color planes, the information representing the presence of chroma shift values ​​is reset and no further information representing chroma shift values ​​is signaled. According to a first aspect of at least one modality, a video coding method comprises, for at least one block of at least one image of a video, encoding the at least one block and corresponding signaling information comprising at least one information representative of the presence of chroma shift values, wherein when chroma is present and does not use separate color planes, the information representative of the presence is established Rwn Ln / zznz / E / YiAi chroma shift values ​​and signaling information further comprises representative information of chroma shift values ​​and where, when chroma is not present or uses separate color planes, the representative information of the presence of chroma shift values ​​is reset, and no further representative information of chroma shift values ​​is signaled. According to a second aspect of at least one modality, a video decoding method comprises, for at least one block of at least one image of a video, obtaining signaling information comprising at least one representative information of the presence of chroma shift values, provided that the representative information of the presence of chroma shift values ​​is established, obtaining representative information of chroma shift values ​​from the signaling information, and decoding the at least one block based on the obtained signaling information. According to a third aspect of at least one modality, an apparatus comprises an encoder for encoding image data for at least one block in an image or video, wherein the encoder is configured to encode the at least one block and corresponding signaling information comprising at least one information representative of the presence of chroma shift values, wherein when chroma is present and does not use separate color planes, the information representative of the presence of chroma shift values ​​is established and the signaling information further comprises information representative of chroma shift values, and wherein when chroma is not present or uses separate color planes, the information representative of the presence of chroma shift values ​​is reset, and no further information representative of chroma shift values ​​is signaled. According to a fourth aspect of at least one modality, an apparatus comprises a decoder for decoding image data for at least one block in an image or video, wherein the decoder is configured to obtain signaling information comprising at least one representative information of the presence of chroma shift values, provided that the representative information of the presence of chroma shift values ​​is established, obtain representative information of chroma shift values ​​from the signaling information, and decode the at least one block based on the obtained signaling information. According to a fifth aspect of at least one modality, a bit stream comprises at least one block and corresponding signaling information comprising at least one information representing the presence of chroma shift values, wherein when chroma is present and does not use separate color planes, the information representing the presence of chroma shift values ​​is established and the signaling information further comprises information representing chroma shift values, and wherein when chroma is not present or uses separate color planes, the information representing the presence of chroma shift values ​​is reset, and no further information representing chroma shift values ​​is signaled. According to a sixth aspect of at least one modality, a computer program is presented that comprises program code instructions executable by a processor; the computer program implements the stages of a method according to at least the first or second aspect. According to a seventh aspect of at least one modality, a computer program product is presented that is stored on a non-transient, computer-readable medium and comprises program code instructions executable by a processor; the computer program product implements the steps of a method according to at least the first or second aspect. BRIEF DESCRIPTION OF THE FIGURES Figure 1 illustrates a block diagram of an example Rwn Ln / zznz / E / YiAi of 100 video encoder. Figure 2 illustrates a block diagram of an example 200 video decoder. Figure 3 illustrates a block diagram of an example of a system in which various aspects and modalities are implemented. Figure 4A illustrates an example of a flowchart for coding according to an illustrative modality. Figure 4B illustrates an example of a flowchart for decoding according to an illustrative modality. Figure 5 shows a high-level representation of an end-to-end workflow support content delivery of video encoded according to an example of the present principles. Figure 6A illustrates an example flowchart for coding according to a second example modality. Figure 6B illustrates an example flowchart for decoding according to a second example modality. DETAILED DESCRIPTION OF THE INVENTION Figure 1 illustrates the block diagram of an example video encoder 100. Examples of video encoders comprise a High Efficiency Video Coding (HEVC) encoder compliant with the HEVC standard, or an HEVC encoder in which improvements are made to the HEVC standard, or an encoder employing HEVC-like technologies such as a Joint Scan Model (JEM) encoder being developed by the Joint Video Scan Team (JVET) for the Versatile Video Coding (VVC) standard, or other encoders. Before encoding, the video sequence may undergo pre-coding processing (101). This is done, for example, by applying a color transformation to the input color image (e.g., converting RGB 4:4:4 to YCbCr 4:2:0) or by remapping the input image components to obtain a signal distribution more resilient to compression (e.g., using histogram equalization of one of the color components). Metadata may be associated with the pre-processing and attached to the bitstream. In encoder 100, an image is encoded using the encoder elements as described below. The image to be encoded is partitioned (102) and processed into units, e.g., CU. Each unit is encoded using, e.g., an intra- or inter-mode. When a unit is encoded in an intra-mode, it performs intra-prediction (160). In an inter-mode, motion estimation (175) and compensation (170) are performed. The encoder decides (105) which intra- or inter-mode to use to encode the unit and indicates the intra- or inter-mode decision by, e.g., a prediction mode flag. Prediction residues are calculated, e.g., by subtracting (110) the predicted block from the original image block. Next, the prediction residues are transformed (125) and quantized (130). The quantized transformation coefficients, as well as the movement vectors and other syntax elements, are encoded by entropy (145) to output a bit stream. The encoder can either omit the transformation and apply quantization directly to the untransformed residue signal. Alternatively, the encoder can omit both the transformation and quantization; that is, the residue is encoded directly without applying either the transformation or quantization processes. The encoder decodes an encoded block to provide a reference for further predictions. The quantized transformation coefficients are dequantized (140) and inversely transformed (150) to decode the prediction residuals. By combining (155) the decoded prediction residuals and the predicted block, an image block is reconstructed. Loop filters (165) are applied to the reconstructed image to perform, for example, block effect / SAO (adaptive sample shift) filtering to reduce encoding artifacts. The filtered image is stored in a reference image buffer (180). Figure 2 illustrates a block diagram of an example video decoder 200. Examples of video decoders comprise a High Efficiency Video Coding (HEVC) decoder compliant with the HEVC standard, or an HEVC decoder in which improvements are made to the HEVC standard, or a decoder employing HEVC-like technologies such as a Joint Scan Model (JEM) decoder being developed by the Joint Video Scan Team (JVET) for the Versatile Video Coding (VVC) standard, or other decoders. In the example of the 200 decoder, a bit stream is decoded by the decoder elements as described below. The 200 video decoder typically performs a reciprocal decoding pass to the encoding pass, as described in Figure 1, which performs video decoding as part of encoding the video data. The 100 encoder also typically performs video decoding as part of encoding video data. In particular, the decoder input includes a video bitstream, which can be generated by the Rwn Ln / zznz / E / YiAi video encoder 100. The bit stream is first decoded by entropy (230) to obtain transform coefficients, motion vectors, image partitioning information, and other encoded information. The image partitioning information indicates the size of the CTUs and how a CTU is divided into CUs and possibly PUs where appropriate. The decoder can therefore partition (235) the image into CTUs, and each CTU into CUs, according to the decoded image partitioning information. The transform coefficients are dequantized (240), which includes at least one modality to adapt the chroma quantization parameter described below, and inversely transformed (250) to decode the prediction residues. By combining (255) the decoded prediction residues and the predicted block, an image block is reconstructed. The predicted block can be obtained (270) from intraprediction (260) or motion-compensated prediction (i.e., interprediction) (275). As described above, AMVP and fusion mode techniques can be used to derive motion vectors for motion compensation, which can use interpolation filters to compute interpolated values ​​for subinteger samples of a reference block. Looping filters (265) are applied to the reconstructed image. The filtered image is stored in a reference image buffer (280). The decoded image may further undergo post-decoding processing (285), for example, an inverse color transformation (e.g., conversion from YCbCr 4:2:0 to RGB 4:4:4) or an inverse remapping that performs the reverse of the remapping process carried out in the pre-coding processing (101). The post-decoding processing may use metadata derived in the pre-coding processing and signaled in the bitstream. Figure 3 illustrates a block diagram of an example system in which various aspects and modes are implemented. System 1000 can be realized as a device that includes the various components described below and is configured to perform one or more of the aspects described in this application. Examples of such devices include, but are not limited to, various electronic devices such as personal computers, laptops, smartphones, tablet computers, digital television multimedia set-top boxes, digital television receivers, personal video recording systems, connected home devices, encoders, transcoders, and servers. The elements of System 1000, individually or in combination, can be implemented on a single integrated circuit, multiple ICs, and / or discrete components.For example, in at least one mode, the processing and encoder / decoder elements of the 1000 system are distributed across multiple ICs and / or. Rwn Ln / zznz / E / YiAi discrete components. In various configurations, the 1000 system is communicatively coupled to other similar systems, or other electronic devices, by means of, for example, a communication bus or through dedicated input and / or output ports. In various configurations, the 1000 system is configured to implement one or more of the aspects described in this document. System 1000 includes at least one processor 1010 configured to execute instructions loaded into it to implement, for example, the various aspects described in this document. The processor 1010 may include embedded memory, an input / output interface, and various other circuit systems as known in the art. System 1000 includes at least one memory 1020 (e.g., a volatile memory device and / or a non-volatile memory device). System 1000 includes a storage device 1040, which may include non-volatile and / or volatile memory, including, but not limited to, EEPROM, ROM, PROM, RAM, DRAM, SRAM, flash memory, a magnetic disk drive, and / or an optical disk drive. The storage device 1040 may include, as non-limiting examples, an internal storage device, an attached storage device, and / or a network-accessible storage device. The 1000 system includes a 1030 encoder / decoder module configured, for example, to Rwn Ln / zznz / E / YiAi processes data to provide encoded or decoded video, and the 1030 encoder / decoder module may include its own processor and memory. The 1030 encoder / decoder module represents a module that may be included in a device to perform encoding and / or decoding functions. As is known, a device may include one or both encoding and decoding modules. Furthermore, the 1030 encoder / decoder module may be implemented as a separate element of the 1000 system or may be incorporated within the 1010 processor as a hardware and software combination, as is known to those skilled in the art. The program code to be loaded into processor 1010 or encoder / decoder 1030 to perform the various functions described herein may be stored in storage device 1040 and subsequently loaded into memory 1020 for execution by processor 1010. Depending on the configuration, one or more of the processor 1010, memory 1020, storage device 1040, and encoder / decoder module 1030 may store one or more of various elements during the execution of the processes described herein. Such stored elements may include, but are not limited to, the input video, the decoded video or portions of the decoded video, bit sequences, arrays, variables, and Rwn Ln / zznz / E / YiAi intermediate or final results of the processing of equations, formulas, operations and operational logic. In several configurations, the memory within the processor 1010 and / or the encoder / decoder module 1030 is used to store instructions and to provide working memory for processing required during encoding or decoding. In other configurations, however, memory external to the processing device (for example, the processing device may be the processor 1010 or the encoder / decoder module 1030) is used for one or more of these functions. The external memory may be memory 1020 and / or storage device 1040, for example, dynamic volatile memory and / or non-volatile flash memory. In several configurations, external non-volatile flash memory is used to store the television's operating system.In at least one mode, a fast external dynamic volatile memory such as RAM is used as working memory for video encoding and decoding operations, such as MPEG-2, HEVC, or WC. Input to the elements of system 1000 can be provided through various input devices as indicated in block 1130. Such input devices include, but are not limited to, (i) an RF portion that receives a transmitted RF signal, for example, through the air by means of a broadcaster Rwn Ln / zznz / E / YiAi (ii) a composite input terminal, (iii) a USB input terminal, and / or (iv) an HDMI input terminal. In various configurations, the input devices of block 1130 have associated input processing elements as known in the art. For example, the RF portion may be associated with elements necessary to (i) select a desired frequency (also referred to as selecting a signal, or band-limiting a signal to a frequency band), (ii) downconvert the selected signal, (iii) band-limit again to a narrower frequency band to select (for example) a signal frequency band, which may be called a channel in certain configurations, (iv) demodulate the downconverted and band-limited signal, (v) perform error correction, and (vi) demultiplex to select the desired data packet stream.The RF portion of various modes includes one or more elements to perform these functions, for example, frequency selectors, signal selectors, band limiters, channel selectors, filters, downconverters, demodulators, error correctors, and demultiplexers. The RF portion may include a tuner that performs several of these functions, including, for example, downconverting the received signal to a lower frequency (e.g., an intermediate frequency or a frequency close to 5Hz). Rwn Ln / zznz / E / YiAi baseband) or baseband. In one digital television decoder mode, the RF portion and its associated input processing element receive an RF signal transmitted through a wired medium (e.g., cable) and performs frequency selection by filtering, downconversion, and further filtering to a desired frequency band. Various modes rearrange the order of the elements described above (and others), remove some of these elements, and / or add other elements that perform similar or different functions. Adding elements may include inserting elements between existing elements, such as, for example, inserting amplifiers and an analog-to-digital converter. In various modes, the RF portion includes an antenna. Furthermore, the USB and / or HDMI terminals may include respective interface processors for connecting the 1000 system to other electronic devices via USB and / or HDMI connections. It should be understood that various aspects of input processing, such as Reed-Solomon error correction, may be implemented, for example, within a separate input processing IC or within the 1010 processor as required. Similarly, aspects of USB or HDMI interface processing may be implemented within separate interface ICs or within the 1010 processor as required. The demodulated, error-corrected, and demultiplexed stream is provided for various processing elements, including, for example, the 1010 processor and the 1030 encoder / decoder, which operate in conjunction with the memory and storage elements to process the data stream as required for presentation on an output device. Various elements of the 1000 system can be provided within an integrated housing. Within the integrated housing, the various elements can be interconnected and transmit data between them using a suitable connection arrangement, for example, an internal bus as known in the art, which includes the I2C bus, wiring, and printed circuit boards. The 1000 system includes a 1050 communication interface that enables communication with other devices via the 1060 communication channel. The 1050 communication interface may include, but is not limited to, a transceiver configured to transmit and receive data over the 1060 communication channel. The 1050 communication interface may also include, but is not limited to, a modem or network card, and the 1060 communication channel may be implemented, for example, within a wired and / or wireless medium. Data is transmitted to the 1000 system in various modes using a Wi-Fi network such as IEEE 802.11. The signal Rwn Ln / zznz / E / YiAi Wi-Fi in these modes is received through the 1060 communication channel and the 1050 communication interface, which are adapted for Wi-Fi communication. The 1060 communication channel in these modes typically connects to an access point or router that provides access to external networks, including the internet, to enable streaming applications and other free-to-air communications. Other modes provide data transmitted to the 1000 system using a digital television set-top box that supplies the data through the HDMI connection of input block 1130. Still other modes provide data transmitted to the 1000 system using the RF connection of input block 1130. The 1000 system can provide an output signal to various output devices, including a display 1100, speakers 1110, and other peripheral devices 1120. Other peripheral devices 1120 include, in various configurations, one or more of a standalone DVR, a disc player, a stereo system, a lighting system, and other devices that provide a function based on the output of the 1000 system. In various configurations, control signals are communicated between the 1000 system and the display 1100, speakers 1110, or other peripheral devices 1120 using signaling such as AV.Link, CEC, or other communication protocols that allow device-to-device control with or without user intervention. The output devices can be communicatively coupled. Rwn Ln / zznz / E / YiAi to the 1000 system via dedicated connections through the respective 1070, 1080, and 1090 interfaces. Alternatively, the output devices can be connected to the 1000 system using the 1060 communication channel via the 1050 communication interface. The 1100 display and 1110 speakers can be integrated into a single unit with the other 1000 system components in an electronic device such as a television. In various configurations, the 1070 display interface includes a display controller, such as a sync controller chip (T-Con). The display 1100 and speaker 1110 may alternatively be separate from one or more of the other components, for example, if the RF portion of input 1130 is part of a separate digital television decoder. In various configurations where the display 1100 and speakers 1110 are external components, the output signal may be provided by means of dedicated output connections, including, for example, HDMI ports, USB ports, or COMP outputs. The implementations described herein may be implemented, for example, in a method or process, a device, a computer program, a data stream, or a signal. Even if described only in the context of a single implementation form (for example, described only as a method), the implementation of the The described features can also be implemented in other forms (e.g., a device or a program). A device can be implemented in, for example, suitable hardware, software, and firmware. Methods can be implemented in, for example, a device such as a processor, which refers to processing devices in general, including, for example, a computer, a microprocessor, an integrated circuit, or a programmable logic device. Processors also include communication devices such as, for example, computers, cell phones, personal digital assistants (PDAs), and other devices that facilitate the communication of information between end users. As mentioned earlier, anti-blocking filters are loop filters (165) applied to the reconstructed image to reduce encoding artifacts. These filters require parameters. The following syntax elements are described in the example video encoding system as specified by Draft WC 8. However, other video encoding systems or other versions of WC may use similar mechanisms to signal and use anti-blocking filters. In such an example, the unlocking parameters can be encoded either in the Picture Parameter Set (PPS), in the Segment Header (SH), or in the Rwn Ln / zznz / E / YiAi image header (PH, for its English acronyms) . This is controlled by a PPS flag called deblocking_filter_override_enabled_flag. If this flag is equal to one, the parameters are encoded well in PH or SH, otherwise, they are encoded in PPS. This is illustrated through Table 1: Rwn Ln / zznz / E / YiAi Table 1 pic_parameter_set_rbsp( ) { Descriptor deblocking_filter_control_present_flag u(l) if(deblocking filter control present flag) { deblocking_filter_override_enabled_flag u(l) pps_deblocking_filter_disabled_flag u(l) if(!pps deblocking filter disabled flag {) pps_beta_offset_div2 se (v) pps_tc_offset_div2 se (v) pp s_cb_b et a_o ffse t_div2 se (v) pp s_cb_t c_o ffs et_div2 se (v) pps or beta offset div2 se (v) pp s_c r_offset_div2 se (v)}} if(deblocking_filter_override_enabled_flag) dbf info in ph flag u(l) The semantics of the flags are as follows: - deblocking_filter_override_enabled_flag equal to 1 specifies the presence of ph_deblocking filter_override flag in PHs that refer to the PPS or slice_deblocking_filter_override_flag in segment headers that refer to the PPS. - deblocking_filter_override_enabled_flag equal to 0 specifies the absence of ph_deblocking_filter_override_flag in PHs that refer to the PPS or slice deblocking filter override flag in slice headers that refer to the PPS. - when it is not present, it is inferred that the value of deblocking_filter_override_enabled_flag is equal to 0. If override is allowed, dbf_info_in_ph_flag specifies whether the parameters are PH or SH encoded. More specifically: - dbf_info_in_ph_flag equal to 1 specifies that filter information against block effect is present in the PH syntax structure and is not present in segment headers that refer to the PPS that do not contain a PH syntax structure. - dbf_info_ln_ph_flag equal to 0 specifies that filter information against block effect is not present in the PH syntax structure and may be present in segment headers that refer to the PPS that do not contain a PH syntax structure. - when it is not present, it is inferred that the value of dbf_info_ín_ph_flag is equal to 0. Rwn Ln / zznz / E / YiAi In the image header, the parameters are encoded as illustrated in Table 2. Table 2 Rwn Ln / zznz / E / YiAi picture_header_structure( ) { Descritor if(deblocking_filter_override_enabled_flag && dbf_info_in_ph_flag) { ph_deblocking_filter_override_flag u(l) if(ph deblocking filter override flag) { ph_deblocking_filter_disabled_flag u(l) if(!ph deblocking filter disabled flag) { ph_be t a_o f f s e t_div2 se (v) ph_t c_o f f s e t_div2 se (v) ph_cb_be ta_o f f s e t_div2 se (v) ph_cb_tc_o f f se t_div2 se (v) ph_cr_be ta_offset_div2 se (v) ph_cr_tc_o f f se t_di v2 se (v)}}} En la cabecera de segmento, los parámetros se codifican como se ilustra en la Tabla 3. Tabla 3 slice_header( ) { Descritor if(deblocking_filter_override_enabled_flag && !dbf_info_in_ph_flag) slice_deblocking_filter_override_flag u(l) if(slice deblocking filter override flag) { slice_deblocking_filter_disabled_flag u(l) if(!slice_deblocking_filter_disabled_flag) { s1ice_beta_offset_div2 se (v) s1i ce_tc_o ffse t_div2 se (v) s1ice_cb_beta_offset_div2 se (v) s1ice_cb_tc_offset_div2 se (v) s1ice_cr_beta_offset_div2 se (v) s1ice_cr_tc_offset_div2 se (v)}} Rwn Ln / zznz / E / YiAi At all three levels (PPS, PH, and HS), the encoded unlock parameters can be beta offset div2, tc_offset_div2, cb_beta_offset_div2, cb_tc_offset_div2, or beta offset div2, and cr te offset div2. These represent the beta and te offsets used for unlocking and can be encoded for luminance and chroma components (cb and cr). Unlike many other syntaxes in video encoding systems, chroma parameters can be encoded independently of the chroma format. Specifically, the yuv400 chroma format is one where only luminance components exist. That is, not all the syntax and code related to chroma are used. Similarly, there is an encoding mode where the separable encoding of color components is called yuv444. In this case, the chroma components are treated as independent luminance components. The configuration corresponds to the SPS separate_colour_plane_flag, which is coded as illustrated in Table 4. Rwn Ln / zznz / E / YiAi Table 4 seq_parameter_set_rbsp( ) { chroma_format_idc descriptor u(2) if(chroma format idc = = 3) separate_colour_j>lane_flag u (1) In this table, a chroma_format_idc value equal to 3 indicates a chroma format of 444. Therefore, there are two configurations where chroma-related syntax will not be used. A variable called ChromaArrayType can be used to distinguish this case and can be calculated as follows: When separate_colour_plane_flag is equal to 0, ChromaArrayType is set to chroma_format_idc; otherwise, ChromaArrayType is set to 0. As a result, if ChromaArrayType is equal to zero, no saturation-related syntax will be used. However, the filter parameters for chroma-related block effects are encoded independently of the ChromaArrayType value. That is, even if chroma is not used, the following four syntax elements are encoded: cb_beta offset div2, cb_tc offset div2, cr_beta_offset_div2, and cr_tc_offset_div2. Therefore, such signaling is redundant and costs some bits that are never used. Furthermore, this makes it more difficult for the encoder designer to set irrelevant values. The modalities described from here on have been designed with the above in mind. In at least one modality, a video coding system that handles at least one block of at least one image from a video comprises an encoding process and a decoding process that respectively provide or use video-related signaling information, wherein the signaling information comprises chroma anti-block filter parameters when the information representing the presence of the anti-block filter is true, the information representing the disabling of the anti-block filter is false, and the information representing the chrominance type is true. In other words, the presence of chroma anti-block filter parameters is subject to testing by a set of syntax elements.This allows for improved coding efficiency by reducing the overall size of the information required, since these parameters are present in the bit stream only when needed. Figure 4A shows an example flowchart for the encoding process according to an illustrative modality. Such a process is implemented, for example, in the video encoder 100 described above. In this process, in step 401, the encoder checks the flag indicating that the blocking filter control parameters are present. If so, in the Yes branch, the encoder checks, in step 402, the flag indicating that the blocking filter is disabled. If not, in the No branch, the encoder checks, in step 403, the chroma type. This test determines whether yuv400 or yuv444 are used; in other words, whether only luminance components (without chroma) are used, or whether the luminance and chrominance are encoded separately on different planes.If this is the case, in the No Chroma or Separate Planes branch, the encoder specifies, in step 404, the blocking filter parameters to be applied to the chrominance samples. In other words, the blocking filter parameters are added to the signaling information to be encoded. In all other cases (the No branch in step 401 or 403, the Yes branch in step 402), no blocking filter parameters will be specified for the chrominance. Finally, in step 405, the block is encoded with the signaling information. The process iterates over the others. Rwn Ln / zznz / E / YiAi blocks in stage 406 until providing the encoded bit stream in stage 407. The person skilled in the art will recognize that the whole encoding process comprises other stages not represented here as they are not related to the modality. Figure 4B illustrates an example flowchart for the decoding process according to an illustrative modality. Such a process is implemented, for example, in the video decoder 200 but also in the video encoder 100, both devices described above. The process is described with respect to the decoder. In this process, in step 411, the decoder checks the flag indicating that the blocking filter control parameters are present. If so, in the Yes branch, the decoder checks, in step 412, the flag indicating that the blocking filter is disabled. If not, in the No branch, the decoder checks, in step 413, the chroma type.Similarly, for the encoding process, this test determines whether yuv400 or yuv444 are used; in other words, whether only luminance components (without chroma) are used, or whether luminance and chrominance are encoded separately on different planes. If so, in the "No Chroma" or "Separate Planes" branch, the decoder obtains, in step 414, the blocking filter parameters to be applied to the chrominance samples. In all other cases (the "No" branch of step 411 or 413, the "Yes" branch of step 412), no blocking filter parameters are specified for chrominance, and therefore, suitable blocking filter parameters are inferred in step 415. Finally, in step 405, the block is decoded, and the blocking filter is applied with the obtained or inferred parameters.The person who is an expert in the technique will recognize that the entire coding process includes other stages not represented here since they are not related to the modality. The process in Figures 4A and 4B resolves the redundancy problem because the encoding of chroma unlock parameters is conditioned by the chroma format. In an illustrative implementation using the WC 8 draft syntax, this can be done by testing the value of the ChromaArrayType syntax element. When ChromaArrayType is zero, the following parameters should not be encoded at the PPS, PH, or SH level: beta_offset_div2, tc_offset_div2, cb_beta_offset_div2, cb_tc_offset_div2, cr_beta_offset_div2, and cr_tc_offset_div2. Table 5 shows an illustrative modality according to an implementation applied to WC syntax, where the ChromaArrayType syntax element is tested at the image parameter set level. Rwn Ln / zznz / E / YiAi Rwn Ln / zznz / E / YiAi Table 5 pic_parameter_set_rbsp( ) { Descritor deblocking filter control present flag u(l) if(deblocking_filter_control_present_flag) { deblocking_filter_override_enabled—flag u(l) pps_deblocking_filter_disabled_flag u(l) if(!pps_deblocking_filter_disabled_flag) { pps_beta_offset_div2 if (v) pps_tc_offset_div2 if (v) if(ChromaArrayType != 0) { pps_cb_beta_offset_div2 if (v) pps cbtc offset div2 if (v) pps_cr_beta_offset_div2 if (v) pps cr te offset div2 if (v)}}} if(deblocking_filter_override_enabled_flag) db f_i nf o_i n_ph_flag u (1) Table 6 shows an illustrative way of understanding with an implementation applied to the VVC syntax, where the ChromaArrayType syntax element is applied at the image level. Rwn Ln / zznz / E / YiAi Table 6 picture_header_structure( ) { Descritor if (deblocking_fi1ter_override_enabled_flag && dbf_info_in_ph_flag) { ph_deblocking_filter_override_flag u(l) if(ph_deblocking_filter_override_flag) { ph_deblocking_filter_disabled_flag u(l) if(!ph_deblocking_filter_disabled_flag) { ph_beta_offset_div2 se (v) ph_tc_of fset_div2 se (v) if(ChromaArrayType != 0){ ph_cb_beta_offset_div2 se (v) ph_cb_t c_o f f s e t_div2 se (v) ph_cr_beta_offset_div2 se (v) ph_cr_tc_offset_div2 se (v)}}}} La Tabla 7 muestra una modalidad ilustrativa de acuerdo con una implementación aplicada a la sintaxis VVC, donde el elemento de sintaxis ChromaArrayType se prueba en el nivel de cabecera de segmento. Tabla 7 slice_header( ) { Descritor if(deblocking filter override enabled flag && !dbf_info_in_ph_flag) slice_deblocking_filter_override_flag u(l) if(slice_deblocking_filter_override_flag) { slice_deblocking_filter_disabled_flag u(l) if(!slice_deblocking_filter_disabled_flag) { slice_beta_offset_div2 se (v) slice_tc_offset_div2 se (v) if(ChromaArrayType != 0){ slice cb beta offset div2 se (v) slice cb te offset div2 se (v) slice cr beta offset div2 se (v) slice cr te offset div2 se (v)}}} This mechanism simplifies the encoder design already Rwn Ln / zznz / E / YiAi, when using a yuv400 or yuv444 chroma format with separable color formatting, eliminates the need to specify mock values ​​for unused parameters. It also improves encoding efficiency because some bits are saved at the PPS, PH, or SH level. This is particularly useful when dealing with large datasets or internet traffic. In a second approach, it is proposed to reduce the interaction between SPS and PPS. In fact, ChromaArrayType depends on the SPS syntax elements chroma_format_idc and separate_color plane_flag. Therefore, it may be preferable to avoid using this value within PPS. For this reason, the PPS flag pps_chroma_tool_offsets_present_flag can be used. This flag is intended to enable / disable all chroma QP offsetting. In addition to the syntax elements illustrated in Table 1, the image parameter set also includes the elements illustrated in Table 8. Rwn Ln / zznz / E / YiAi Table 8 pic_parameter_set_rbsp( ) { Descritor pps_chroma_tool_offsets_present_flag u (1) if (pps chroma tool offsets present flag) { pps_cb_gp_offset se (v) pps_cr_qp_offset se (v) pps_j oint_cbcr_qp_offset_present_flag u(l) if(pps_j oint_cbcr_qp_offset_present_flag) pps_j oint_cbcr_qp_offset_value se (v) pps_slice_chroma_qp_offsets_present_flag u(l) pp s_cu_chroma_qp_of f s e t_li s t_enabled_flag u(l)} deblocking_filter_control_present_flag u(l) if(deblocking_filter_control_present_flag) { deblocking_filter_override_enabled_flag u(l) pps_deblocking_filter_disabled_flag u(l) if(!pps deblocking filter disabled flag) { pps_beta_offset_div2 se (v) pps_tc_offset_div2 se (v) pps_cb_beta_offset_div2 se (v) pps_cb_tc_offset_div2 se (v) pps_cr_beta_offset_div2 se (v) pps_cr_tc_offset_div2 se (v)}} La semántica de estos elementos de sintaxis es la siguiente: - pps_chroma_tool_offsets_present_flag equal to 1 specifies that the syntax elements related to chroma tool offsets are present in the PPS RBSP syntax structure. - pps_chroma_tool_offsets_present_flag equal to 0 specifies that the syntax elements related to chroma tool offsets are not present in the PPS RBSP syntax structure. - When ChromaArrayType is equal to 0, the value of pps_chroma_tool_offsets_present_flag should be equal to 0. Therefore, in this second mode, the same flag is used to check if chroma components are available, as illustrated in Table 9. Rwn Ln / zznz / E / YiAi Table 9 pic_parameter_set_rbsp( ) { Descritor deblocking_filter_control_present_flag u(l) if(deblocking_filter_control_present_flag) { deblocking_filter_override_enabled_flag u(l) pps_deblocking_filter_disabled_flag u(l) if(!pps_deblocking_filter_disabled_flag) { pps_beta_offset_div2 se (v) pps_tc_offset_div2 se (v) if(pps_chroma_tool_offsets_present_flag { pps_cb_beta_offset_div2 se (v) pps cb te offset div2 se (v) pps_cr_beta_offset_div2 se (v) pps_cr_tc_offset_div2 se (v)}}} if(deblocking_filter_override_enabled_flag) dbf info in ph flag u(l) Rwn Ln / zznz / E / YiAi Desde el punto de vista editorial, se propone cambiar el nombre de la bandera pps_chroma_tool_offsets_present_flag a pps_chroma_tool_offsets_dbf_present_flag. Esto se ilustra en la Tabla 9.1 a continuación. Tabla 9.1 pic_parameter_set_rbsp( ) { Descriptor deblocking_filter_control_present_flag u(l) if(deblocking filter control present flag) { deblocking filter override enabled flag u (1) pps_deblocking_filter_disabled_flag u(l) if(!pps_deblocking_filter_disabled_flag_di_offset is (v) pps_tc_offset_div2 is (v) if(pps_chroma_tool_offsets_dbf_present_flag { pps_cb_beta_offset_div2 is (v) pps_cb is offset_div2 is (v) pps_cr_beta_offset_div2 is (v) pps cr is offset div2 is (v)}}} if(deblocking_filter_override_enabled_flag) db f_i nf o_i n_ph_flag u(l) The semantics of this syntax element is as follows: Rwn Ln / zznz / E / YiAi - pps chroma tool offsets dbf present flag equal to 1 specifies that syntax items related to chroma tool offsets and filter parameters against block effect are present in PPS's RBSP syntax structure. - pps_chroma_tool_offsets_dbp_present_flag equal to 0 specifies that syntax elements related to chroma tool offsets and filter parameters against block effect are not present in the PPS RBSP syntax structure. - When ChromaArrayType is equal to 0, the value of pps chroma tool offsets dbf present flag should be equal to 0. In at least one variant, it is proposed to avoid any dependence of the PPS on SPS and to decouple the control of the chroma keying tool and the filter parameters against chroma blocking. This can be implemented by inserting a specific flag in the PPS, dedicated to signaling that the filter parameters against chroma blocking are present in the PPS in question. This can take the form of the syntax element pps_chroma_deblocking_filter_parms_present_flag and the modified PPS syntax table illustrated in Table 10. Rwn Ln / zznz / E / YiAi Tabla 10 pic_parameter_set_rbsp( ) { Descritor deblocking_filter_control_present_flag u(l) if(deblocking filter control present flag) { deblocking filter override enabled flag u(l) pps_deblocking_f ilter_disabled_flag u(l) if(!pps_deblocking_filter_disabled_flag) { pps beta offset div2 se (v) pps_tc_offset_div2 se (v) pps_chroma_deblocking_filter_params_present_fla g u(l) if (pps chroma deblocking filter params present flag) { pps_cb_beta_of f set_div2 se (v) pps_cb_tc_offset_div2 se (v) pps cr beta offset div2 se (v) pp s_c r_t c_o f f s e t_div2 se (v)}}} if(deblocking_filter_override_enabled_flag) dbf_info_in_ph_flag u(l) The advantage of this variant is that the signaling of the filter parameters against chroma block effects in the PPS is decoupled from the signaling of the chroma QP offset parameters, which can depend on `pps_chroma tool offsets present_flag` as specified in draft WC 8, for example. The semantics of the new syntax element of the PPS level flag are as follows: - pps_chroma_deblocking_filter_params_present_flag equal to 1 specifies that chroma decoded image parameters are present in the PPS RBSP syntax structure. - pps_chroma_deblocking_filter_params_present_flag equal to 0 specifies that chroma decoded image parameters are not present in the PPS RBSP syntax structure. - When ChromaArrayType is equal to 0, the value of pps_chroma_deblocking_filter_params_present_flag should be equal to 0. In at least one variant, a PPS level flag is introduced to indicate that chroma is available. For example, it is called `pps_chroma_available_flag`, and it essentially repeats the information that `ChromaArrayType` is not 0 at a PPS level. If this new flag is zero or false, both the chroma unlock flag and the chroma shift flag must be zero. It is a bitstream conformance requirement that the value of `pps_chroma_available_flag` must be zero when `ChromaArrayType` is zero and the value of the `pps_chroma_available_flag` is zero. Rwn Ln / zznz / E / YiAi must be one when chromaArrayType is one. According to a first aspect of this modality, the parameters of the filter against chroma block effect should not be present in the PPS, as illustrated in Table 11. According to a further aspect, the syntax items related to PPS chroma QP shifts, which starts with pps_chroma_tool_offsets_present_flag, will not be present in the PPS if the pps_chroma_available_flag flag is equal to zero or false. Table 11 pic_parameter_set_rbsp( ) { Descriptor pps chroma available flag u(l) if (pps chroma available flag) { pps_chroma_tool_offsets_present_flag u(l) if(pps_chroma_tool_offsets_present_flag) { pps_cb_set_qp_se pps_offset_se_qp_c (v) pps_j oint_cbcr_qp_offset_present_flag u(l) if (pps joint cbcr qp offset present flag) pps joint cbcr qp offset valued if (v) pps_slice_chroma_qp_offsets_present_flag u(l) pp s_chroma_chroma_qp_f_f_f_li t_enabled_flag u(l)}} deblocking filter control present flag u(l) if(deblocking_filter_control_present_flag) { deblocking filter override enabled flag u(l) pps_deblocking_filter_disabled_flag u(l) if(!pps_deblocking_filter_disabled_flag) { pps_beta_offset_div2 se (v) pps_tc_offset_div2 se (v) if(pps_chroma_available_flag) { pps_cb_beta_offset_div2 se (v) pps_cb_tc_offset_div2 se (v) pps cr beta offset div2 se (v) pps cr te offset div2 se (v)}}} if(deblocking_filter_override_enabled_flag) dbf info in ph flag u (1) Rwn Ln / zznz / E / YiAi According to one variant of this mode, the pps_chroma_deblocking_filter_params_present_flag flag will be set as described in the previous mode of Table 10 if the pps_chroma_available_flag flag is true. The presence of chroma blocking filtering parameters in the PPS then depends on the value of the pps_chroma_deblocking_filter_params_present_flag flag. If it is not present in the bitstream, the pps_chroma_deblocking_filter_params_present_flag flag should be set to 0. Rwn ίη / ζζηζ / Ε / γίΛΐ Table 12 pic_parameter_set_rbsp( ) { Descritor pps chroma available flag u(D if(pps_chroma_available_flag) { pps_chroma_t°°l_fsets_Present_flag u(l) if(pps_chroma_tool_offsets_present_flag) { pp s_cb_qp_o f f s et se (v) pp s_c r_qp_o f f s et se (v) pps_joint_cbcr_qp_offset_present_flag u(l) if(pps_j oint_cbcr_qp_offset_present_flag) pps_joint_cbcr_qp_offset_value se (v) pps_slice_chroma_qp_offsets_presentaflag u(l) pps_cu_chroma_qp_of f set_li st_enabled_flag u(l)}} deblocking_filter_control_present_flag u(l) if(deblocking_filter_control_present_flag) { deblocking_filter_override_enabled—flag u(l) pps_deblocking_filter_disabled_flag u(l) if(!pps deblocking filter disabled flag) { pps_beta_offset_div2 se (v) pp s_t c_o f f s e t_div2 se (v) if(pps_chroma_available_flag) { pps chroma deblocking filter params present flag u(D if(pps_chroma_deblocking_filter_params_present _flag) { pp s_cb_b e t a_o f f s e t_div2 se (v) pps cb te offset div2 se (v) pps_cr_beta_offset_div2 se (v) pp s_c r_tc_o f f s et_div2 se (v)}}}} if(deblocking filter override enabled flag) dbf info in ph flag u(l) Rwn Ln / zznz / E / YiAi Figure 5 shows a high-level representation of an end-to-end workflow support content delivery of encoded video according to an example of the present principles. The encoder device 100 is configured to implement a method for encoding an image or video bitstream according to at least one modality described above, and the decoder device 200 is configured to implement a method for decoding an image or video bitstream according to at least one modality described above. The two remote devices 100 and 200 communicate over a distribution network 500 that is configured at least to provide the encoded image or video bitstream from device 100 to device 200. The device 100 that is configured to implement an encoding method belongs to a set of devices comprising a mobile device, a communication device, a gaming device, a tablet (or tablet), a computer device such as a laptop computer, a camera, a video camera, an encoding chip, a still image server, and a video server (e.g., a broadcast server, a video-on-demand server, or a web server). The device 200 that is configured to implement a decoding method as described herein belongs to a set of devices comprising a mobile device, a communication device, a gaming device, a multimedia adaptation unit, a television set (or TV), a tablet (or tablet), a computer device such as a laptop computer, a display, a virtual reality headset, and a decoding chip. According to one example, the network is a broadcast network, adapted to distribute images or video images from device 100 to a plurality of decoding devices, including device 200. Networks based on DVB and ATSC are examples of such broadcast networks. According to another example, the network is a broadband network adapted to deliver images or video images from device 100 to a plurality of devices. Rwn Ln / zznz / E / YiAi decoding that includes the Internet, GSM networks or TV networks broadband networks. In the preferred mode, device 200. IP-over-IP networks are examples of such an end-to-end workflow Rwn Ln / zznz / E / YiAi to the end uses a broadcast server for device 100, a television or multimedia adaptation unit for device 200 and a DVB terrestrial broadcast network. In an alternative approach, the NET distribution network is replaced by a packaged physical medium on which the encoded image or video bitstream is stored. Packaged physical media include optical media, such as Blu-ray and UHD Blu-ray discs, as well as memory-based packaging media. This description has outlined various pieces of information, such as syntax, that can be transmitted or stored. This information can be packaged or arranged in a variety of ways, including common methods in video standards such as placing the information in an SPS, a PPS, a NAL unit, a header (e.g., an NAL unit header or a segment header), or an SEI message. Other methods are also available, including common methods for application-level or system-level standards, such as placing the information in one or more of the following: * SDP (Session Description Protocol), a format for describing multimedia communication sessions for the purposes of session announcement and session invitation, for example, as described in RFC and used in conjunction with RTP (Real-Time Transport Protocol) streaming. • MPEG DASH MPD (Dynamic Adaptive Streaming over HTTP, Media Presentation Description) descriptors, for example, as used in DASH and streamed over HTTP, a descriptor is associated with a representation or collection of representations to provide additional features to the content representation. • RTP (Real-Time Transport Protocol) header extensions, for example, as used during RTP transmission. • ISO base media file format, for example, as used in OMAF and using boxes which are object-oriented building blocks defined by a unique type identifier and length also known as atoms in some specifications. • HLS (HTTP Live Stream) manifest transmitted over HTTP. A manifest can be associated, for example, with a version or collection of versions of content to provide features of that version or collection of versions. Figure 6A shows an example of a flowchart for Rwn Ln / zznz / E / YiAi describes the encoding process according to the second illustrative mode. More specifically, it represents an illustrative flowchart for implementing the variant mode corresponding to Table 9 above. Such process 600 is implemented, for example, in the video encoder 100 described above. In this process, in step 602, the encoder checks for the use of chroma and separate color planes. If chroma is used and separate color planes are not, then chroma offset values ​​are required in step 604. This is signaled by a suitable flag (for example, pps_chroma_tool_offsets_present_flag, as in Table 9), and the chroma offset values ​​are indicated, for example, by inserting the elements related to the cb and cr offsets illustrated in Table 9.If this is not the case, in the branch without chroma or separate planes, then no additional signaling related to chroma shift values ​​is indicated. The block is then encoded, in stage 608, with the appropriate signaling information. The process iterates over other blocks in stages 602, 604, and 606 until the encoded bit stream is obtained in stage 608. A person skilled in the art will recognize that the entire encoding process comprises other stages not represented here, as they are unrelated to modality. Figure 6B shows an example of a flowchart for the decoding process according to the second modality Rwn Ln / zznz / E / YiAi is an example. More specifically, it represents an illustrative flowchart for implementing the variant mode corresponding to Table 9 above. Such process 650 is implemented, for example, in the video decoder 200 described above. In this process, in step 652, the decoder checks a flag indicating the presence of chroma offset values ​​(e.g., pps abroma tool offsets present flag, as in Table 9). If this is the case, in step 654, the chroma offset values ​​are obtained, for example, by analyzing the subsequent elements as illustrated in Table 9. If this is not the case, in the branch without chroma or separate planes, no additional signaling related to chroma offset values ​​is obtained. The block is then decoded in step 656 based on the appropriate signaling information.The process iterates over other blocks in stages 652, 654, and 656 until the bit stream has been processed. A person skilled in the technique will recognize that the entire encoding process comprises other stages not depicted here, as they are unrelated to the modality. The reference to a modality or a modality, or to an implementation or an implementation, as well as other variations thereof, means that an aspect, structure, particular characteristic, etc., described in relation to the modality is included in at least one modality. Therefore, Rwn Ln / zznz / E / YiAi The occurrences of the phrase in the modality or in a modality or in the implementation or in an implementation, as well as any other variations, appearing in various places throughout this description do not all necessarily refer to the same modality. Furthermore, this application or its claims may relate to determining various pieces of information. Determining information may include one or more of, for example, estimating information, calculating information, predicting information, or retrieving information from memory. Furthermore, this application or its claims may relate to accessing various pieces of information. Accessing information may include one or more of, for example, receiving information, retrieving information (for example, from memory), storing information, moving information, copying information, calculating information, predicting information, or estimating information.Furthermore, this application or its claims may refer to receiving various pieces of information. "Receiving," like "accessing," is intended to be a broad term. Receiving information may include one or more actions, such as accessing information or retrieving information (e.g., from memory or optical storage). Moreover, receiving is typically involved, in one way or another, during operations such as storing information. Rwn Ln / zznz / E / YiAi process information, transmit information, move information, copy information, delete information, calculate information, determine information, predict information, or estimate information. Furthermore, luma and luminance are used differently and should be understood to have the same meaning. Similarly, chroma and chrominance are used differently and should be understood to have the same meaning. It should be noted that the use of any of the following: / , and / or, and at least one of, for example, in the cases of A / B, A and / or B and at least one of A and B, is intended to encompass the selection of the first listed option (A) only, or the selection of the second listed option (B) only, or the selection of both options (A and B). As a further example, in the cases of A, B and / or C and at least one of A, B and C, such a phrase is intended to encompass the selection of the first listed option (A) only, or the selection of the second listed option (B) only, or the selection of the third listed option (C) only, or the selection of the first and second listed options (A and B) only, or the selection of the first and third listed options (A and C) only, or the selection of the second and third listed options (B and C) only, or the selection of all three options (A and B and C). This can extend, as will become evident to a Rwn Ln / zznz / E / YiAi expert in this and related techniques, for as many elements as are listed. As will be evident to someone skilled in the art, implementations can produce a variety of formatted signals to carry information that can, for example, be stored or transmitted. The information might include, for example, instructions for performing a method, or data produced by one of the described implementations. For instance, a signal might be formatted to carry the bit sequence of a described modality. Such a signal might be formatted, for example, as an electromagnetic wave (e.g., using a portion of the radio frequency spectrum) or as a baseband signal. The format might include, for example, encoding a data stream and modulating a carrier with the encoded data stream. The information carried by the signal might be, for example, analog or digital. The signal might be transmitted over a variety of different wired or wireless links, as is known.The signal can be stored on a processor-readable medium. It is hereby stated that, as of this date, the best method known to the applicant for putting the aforementioned invention into practice is the one that is clear from the present description of the invention.

Claims

1. A video coding method characterized in that it comprises, for at least one block of at least one image of a video, encoding the block and corresponding signaling information comprising at least one information representative of the presence of chroma shift values, wherein when chroma is present and separate color planes are not used, the information representative of the presence of chroma shift values ​​is set to a first value and the signaling information further comprises information representative of chroma shift values.

2. The video coding method according to claim 1, characterized in that when chroma is not present or separate color planes are used, the representative information of the presence of chroma shift values ​​is set to a second value and no additional representative information of chroma shift values ​​is indicated.

3. The video coding method according to claim 1, characterized in that the chroma shift values ​​are parameters of a filter against Rwn Ln / zznz / E / YiAi block effect.

4. The video coding method according to claim 1, characterized in that the representative information of the presence of chroma shift values ​​is indicated in a set of image parameters.

5. The video coding method according to claim 1, characterized in that the representative information of the presence of chroma shift values ​​is indicated at an image level.

6. A video decoding method characterized in that it comprises, for at least one block of at least one image of a video: obtaining signaling information comprising at least one information representative of a presence of chroma shift values, wherein the information representative of the presence of chroma shift values ​​is set to a first value; obtaining information representative of chroma shift values ​​from the signaling information, and decoding the at least one block based on the obtained signaling information and chroma shift values.

7. The video decoding method according to claim 6, characterized in that the chroma shift values ​​are parameters of a block effect filter.

8. The video decoding method according to claim 6, characterized in that the representative information of the presence of chroma shift values ​​is indicated in a set of image parameters.

9. The video decoding method according to claim 6, characterized in that the information representing the presence of chroma shift values ​​is indicated at an image level.

10. A video coding apparatus characterized in that it comprises an encoder configured to, for at least one block of at least one image of a video, encode the at least one block and corresponding signaling information comprising at least one information representing the presence of chroma shift values, wherein when chroma is present and separate color planes are not used, the information representing the presence of chroma shift values ​​is set to a first value and the signaling information further comprises information representing chroma shift values.

11. A video decoding apparatus characterized in that it comprises an encoder configured for, for at least one block of at least one image of a video: obtaining signaling information comprising at least one information representative of a presence of Rwn Ln / zznz / E / YiAi chroma shift values, wherein the information representative of the presence of chroma shift values ​​is set to a first value; obtaining information representative of chroma shift values ​​from the signaling information, and decoding the at least one block based on the obtained signaling information and chroma shift values.

12. The video decoding method according to claim 11, characterized in that the chroma shift values ​​are parameters of a block effect filter.

13. The video decoding method according to claim 11, characterized in that the representative information of the presence of chroma shift values ​​is indicated in a set of image parameters.

14. The video decoding method according to claim 11, characterized in that the information representing the presence of chroma shift values ​​is indicated at an image level.

15. The video decoding apparatus according to claim 10, characterized in that it belongs to a set of devices comprising a mobile device, a communication device, a gaming device, a tablet, a tablet computer, a computer device such as a laptop computer, a still image camera, a video camera, an encoding chip, a still image server, a video server, a broadcast server, a video on demand server, and a web server.

16. The video decoding apparatus according to claim 11, characterized in that it belongs to a set of devices comprising a mobile device, a communication device, a gaming device, an integrated digital connection box, a television set, a television, a tablet, a tablet computer, a computer device, a laptop computer, a display, a display headset, and a decoding chip.

17. A computer program, characterized in that it comprises program code instructions for implementing the steps of a method in accordance with at least one of claims 1 or 6 when executed on a processor.

18. A non-transient, computer-readable medium, characterized in that it comprises program code instructions executable by a processor to implement the steps of a method in accordance with at least one of claims 1 or 6.

Images