Method and device for transmitting loop filter parameters in image or video processing system

Abstract

The image or video processing method and apparatus include: receiving input data associated with a current picture or a current slice in the current picture; determining whether the current picture is a monochrome picture, conditionally transmitting or parsing chroma deblocking parameters, depending on whether the current picture is a monochrome picture; and encoding or decoding the current picture or the current slice. When the current picture is not a monochrome picture, the chroma deblocking parameters are used in a deblocking filtering operation applied to the chroma components of the current picture or the current slice. A syntax element is used to indicate the acquisition of the chroma deblocking parameters, and, based on the value of the syntax element, the chroma deblocking parameters are allowed to be explicitly transmitted in a syntax structure or parsed from a syntax structure, or the chroma deblocking parameters are implicitly inferred.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Patent Application No. 62 / 981,583, filed on February 26, 2020, entitled “Methods and Apparatus of Signalling Loop Filter Parameters for Image and Video Coding.” The entire contents of this U.S. Provisional Patent Application are incorporated herein by reference. Technical Field

[0003] The present invention relates to a method and apparatus for image or video data processing for image or video encoding or decoding, and in particular to loop filter parameter signaling for an image or video processing system. Background Art

[0004] The High-Efficiency Video Coding (HEVC) standard is the latest video codec developed by the Video Codec Experts Group of the Joint Collaborative Team on Video Coding (JCT-VC), part of the ITU-T study group. The HEVC standard relies on a block-based coding structure that divides each slice into multiple Coding Tree Units (CTUs). A CTU consists of an NxN block of luminance (luma) samples and two corresponding blocks of chrominance (chroma) samples. Figure 1An example of a picture being divided into multiple CTUs is shown. In HEVC, although the maximum size of the luma transform block is 64x64, the maximum allowed size of the luma block in a CTU is specified to be equal to 128x128. The CTUs in a slice are processed according to raster scan order. Each CTU is further recursively divided into one or more coding units (CUs) according to the quadtree (QT) partitioning method to accommodate various local features. Each CTU can be a single CU or divided into four smaller units of equal size, which are split nodes of the codec tree. If the units are leaf nodes of the codec tree, the units become CUs, otherwise the quadtree partitioning procedure iteratively partitions each unit until the size of the node reaches the minimum allowed CU size specified in the sequence parameter set (SPS).

[0005] Prediction decisions are made at the CU level, where each CU is coded or decoded using either interpicture (temporal) prediction or intrapicture (spatial) prediction. Once the CU hierarchy tree is partitioned, each CU is further partitioned into one or more prediction units (PUs) based on the PU partition type used for prediction in HEVC. PUs serve as the basic representation blocks for shared prediction information, as the same prediction process is applied to all pixels in a PU, and prediction-related information is transmitted to the decoder on a PU basis. After obtaining the residual signal generated by the prediction process based on the PU partition type, the data of the residual signal belonging to the CU is further partitioned into one or more transform units (TUs) based on another QT block partition structure to convert the residual signal into transform coefficients for compact data representation. TUs are the basic representation blocks used for integer transform and quantization of the residual signal. For each TU, a transform matrix with the same size as the TU is applied to the residual signal to generate transform coefficients, and these transform coefficients are quantized on a TU basis and transmitted to the decoder.

[0006] The terms Coding Tree Block (CTB), Coding Block (CB), Prediction Block (PB), and Transform Block (TB) are defined as a two-dimensional (2-D) sample array that specifies one color component associated with a CTU, CU, PU, and TU, respectively. For example, a CTU consists of one luma CTB, two chroma CTBs, and their associated syntax elements. In HEVC systems, the same quadtree block partitioning structure is generally applied to both luma and chroma components unless the minimum size of the chroma block is reached.

[0007] Various partitionings of a picture: A picture is divided into one or more tile rows and one or more tile columns. A tile is a series of CTUs that covers a rectangular area of a picture. A slice consists of an integer number of complete tiles or an integer number of consecutive complete CTU rows in a tile of a picture. Raster-scan slice mode and rectangular slice mode are two slicing modes supported in video encoding and decoding. In raster-scan slice mode, a slice contains a sequence of complete slices in a raster scan of slices of a picture. In rectangular slice mode, a slice contains multiple complete tiles that together form a rectangular area of a picture, or multiple consecutive complete CTU rows that together form a tile of a rectangular area of a picture. Within the rectangular area corresponding to that slice, the tiles within the rectangular slice are scanned in tile raster scan order. A sub-picture contains one or more slices that together cover a rectangular area of a picture. Figure 2 An example of raster scan slice segmentation of a picture is shown, where the picture is divided into 12 tiles and 3 raster scan slices. Figure 2 As shown, there are 3 tile columns and 4 tile rows in the picture, and each tile consists of 18 CTUs. The first slice of the picture consists of the first 2 tiles, the second slice consists of five consecutive 5 tiles, and the third slice consists of the remaining 5 tiles. Figure 3 An example of rectangular slicing of a picture is shown, where the picture is divided into 24 tiles and 9 rectangular slices. In this example, there are 6 tile columns and 4 tile rows. Except for the fourth, fifth, and sixth rectangular slices, which each have 4 tiles, all other rectangular slices consist of 2 tiles. Figure 4An example of a picture being partitioned into tiles and rectangular slices is shown, where the picture is divided into 4 tiles and 4 rectangular slices. In this example, there are 2 tile columns and 2 tile rows, and each tile contains 54 CTUs. In this example, a slice can contain 2 tiles, or a tile can contain 2 slices. Figure 5 An example of subpicture partitioning of a picture is shown, where the picture is divided into 28 subpictures with different sizes.

[0008] High Level Syntax for Picture Header and Slice Header: Based on Versatile Video Coding (VVC) Draft 8 ， Table 1 lists the picture parameter set RBSP syntax signaled in the picture parameter set (PPS).

[0009] Table 1

[0010]

[0011]

[0012]

[0013]

[0014] Tables 2 and 3 show the syntax of the Picture Header (PH) and Slice Header (SH), respectively, in VVC Draft 8. If the Access Unit Delimiter (AUD) precedes the SPS and PPS, some picture-level syntax elements in the SH cannot be moved to the AUD. Setting the PH can solve this problem.

[0015] Table 2

[0016]

[0017]

[0018]

[0019]

[0020] Table 3

[0021]

[0022]

[0023]

[0024] Summary of the Invention

[0025] An embodiment of an image or video processing method for an image or video encoding or decoding system receives input data associated with a current picture or a current slice within the current picture; determines whether the current picture is a monochrome picture; conditionally transmits or parses chrominance (chroma) deblocking parameters for the current picture or current slice based on whether the current picture is a monochrome picture; and encodes or decodes the current picture or current slice. When the current picture is not a monochrome picture, the chrominance deblocking parameters are used in a deblocking filtering operation applied to the chroma components of the current picture or current slice. Embodiments of the image or video encoding or decoding system transmit or parse the chrominance deblocking parameters for the current picture or current slice only when the current picture is not a monochrome picture, and skips transmitting or parsing the chrominance deblocking parameters for the current picture or current slice when the current picture is a monochrome picture. In some embodiments, when the current picture is a monochrome picture, the deblocking filtering operation is applied only to the luminance (luma) component. Some examples of chroma deblocking parameters include deblocking offsets beta and tC for chroma components Cb and Cr.

[0026] In some embodiments, the current picture is determined to be a monochrome picture based on the value of a Picture Parameter Set (PPS)-level chroma tool offset present flag transmitted in a PPS associated with the current picture. For example, when the PPS-level chroma tool offset present flag is equal to 0, chroma deblocking parameters are not transmitted in the PPS or parsed from the PPS. In one embodiment, the PPS-level chroma tool offset present flag is set to 0 when the syntax element ChromaArrayType transmitted in a corresponding Sequence Parameter Set (SPS) is equal to 0. In some other embodiments, the current picture is determined to be a monochrome picture based on the value of the syntax element ChromaArrayType transmitted in the SPS. For example, when the syntax element ChromaArrayType is equal to 0, chroma deblocking parameters are not transmitted in the picture header (PH) associated with the current picture, while when the syntax element ChromaArrayType is not equal to 0, chroma deblocking parameters are allowed to be transmitted in the PH. In another example, when the syntax element ChromaArrayType is equal to 0, chroma deblocking parameters are not transmitted in a slice header (SH) associated with the current slice, and when the syntax element ChramArrayType is not equal to 0, chroma deblocking parameters are allowed to be transmitted in the SH.

[0027] An embodiment of an image or video processing method for an image or video encoding or decoding system receives input video data associated with a current picture or a current slice within the current picture, determines a syntax element indicating derivation of chroma deblocking parameters for the current picture or the current slice, derives the chroma deblocking parameters, applies a deblocking filtering operation to chroma components of the current picture or the current slice using the chroma deblocking parameters, and encodes or decodes the current picture or the current slice. Depending on the value of the syntax element, the chroma deblocking parameters for the current picture or the current slice may be explicitly transmitted or parsed, or implicitly inferred. In some embodiments, when the current picture is not a monochrome picture, the value of the syntax element may be inferred as a number greater than 0 for the current picture or the current slice within the current picture. For example, the syntax element may be transmitted in a PPS or PH associated with the current picture or in a SH associated with the current slice.

[0028] An embodiment of an image or video processing method determines whether to allow chroma deblocking parameters to be explicitly transmitted in a PPS, PH, or SH syntax structure or to parse the chroma deblocking parameters therefrom, or to implicitly infer the chroma deblocking parameters, based on the value of a syntax element transmitted in the PPS, PH, or SH. For example, when the chroma deblocking parameters are not explicitly transmitted, the chroma deblocking parameters are implicitly inferred to be 0, or are implicitly inferred from corresponding luma deblocking parameters, or are implicitly inferred from another syntax structure.

[0029] In some embodiments, the syntax element is transmitted in or parsed from a PPS associated with the current picture, and when the value of the syntax element is equal to a first value, chroma deblocking parameters are allowed to be explicitly transmitted in or parsed from the PPS. When the value of the syntax element is equal to a second value different from the first value, the chroma deblocking parameters are not present in the PPS. In some other embodiments, the chroma deblocking parameters in the PPS are implicitly inferred to be equal to the corresponding luma deblocking parameters in the PPS.

[0030] In some other embodiments, when the value of the syntax element is equal to a first value, chroma deblocking parameters for the current picture or current slice are allowed to be explicitly transmitted in the PH or SH, or to be parsed from the PH or SH. When the value of the syntax element is equal to a second value different from the first value, the chroma deblocking parameters are not present in the PH or SH. In examples where the syntax element is transmitted in the PH associated with the current picture, when the value of the syntax element is equal to the first value and the chroma deblocking parameters are not present in the PH, the chroma deblocking parameters for the current picture are implicitly inferred to be equal to the chroma deblocking parameters transmitted in the PPS associated with the current picture, and when the value of the syntax element is equal to the second value different from the first value, the chroma deblocking parameters for the current picture may be implicitly inferred to be equal to the corresponding luma deblocking parameters transmitted in the PH associated with the current picture. In an example where the syntax element is transmitted in the SH associated with the current slice, when the value of the syntax element is equal to a first value and the chroma deblocking parameters are not present in the SH, the chroma deblocking parameters for the current slice may be equal to the chroma deblocking parameters transmitted in the PH associated with the current picture, and, when the value of the syntax element is equal to a second value different from the first value, the chroma deblocking parameters for the current slice may be implicitly inferred to be equal to the corresponding luma deblocking parameters transmitted in the SH associated with the current slice.

[0031] Aspects of the present invention also provide an apparatus for an image or video encoding or decoding system. Some embodiments of the apparatus receive input data associated with a current picture or a current slice within the current picture; determine whether the current picture is a monochrome picture; conditionally transmit or parse chroma deblocking parameters for the current picture or current slice, depending on whether the current picture is a monochrome picture; and encode or decode the current picture or current slice. When the current picture is not a monochrome picture, the chroma deblocking parameters are used in a deblocking filtering operation applied to chroma components of the current picture or current slice. Some other embodiments of the apparatus receive input data associated with the current picture or current slice within the current picture; determine a syntax element for indicating chroma deblocking parameters for the current picture or current slice; based on the value of the syntax element, explicitly transmit or parse the chroma deblocking parameters for the current picture or current slice, or implicitly infer the chroma deblocking parameters for the current picture or current slice; apply a deblocking filtering operation to the chroma components of the current picture or current slice using the chroma deblocking parameters; and encode or decode the current picture or current slice. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Various embodiments of the present invention, presented as examples, will be described in detail with reference to the following drawings, in which like reference numerals represent like components, and in which:

[0033] Figure 1 An example of dividing a video picture into multiple CTUs is shown.

[0034] Figure 2 An example of applying raster scan slice partitioning to divide a picture into 12 tiles and 3 raster scan slices is shown.

[0035] Figure 3 An example of applying rectangular slice partitioning to divide a picture into 24 tiles and 9 rectangular slices is shown.

[0036] Figure 4 An example of dividing a picture into 4 tiles and 4 rectangular slices is shown.

[0037] Figure 5 An example of dividing a picture into 28 sub-pictures is shown.

[0038] Figure 6 The present invention is a flowchart illustrating processing image or video data by conditionally transmitting or parsing chroma deblocking parameters according to an embodiment of the present invention.

[0039] Figure 7 3 is a flow chart of processing image or video data by conditionally inferring chroma deblocking parameters according to an embodiment of the present invention.

[0040] Figure 8 An exemplary system block diagram of a video encoding system combined with a video processing method according to an embodiment of the present invention is shown.

[0041] Figure 9 An exemplary system block diagram of a video decoding system combined with a video processing method is shown according to an embodiment of the present invention. DETAILED DESCRIPTION

[0042] It will be readily understood that the components of the present invention, as generally described and illustrated in the figures herein, may be arranged and designed in a variety of different configurations. Accordingly, the following more detailed description of the embodiments of the systems and methods of the present invention, as illustrated in the figures, is not intended to limit the scope of the claimed invention, but is merely representative of the illustrated embodiments of the invention.

[0043] Throughout this specification, references to "an embodiment," "some embodiments," or similar language mean that a particular feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment of the present invention. Therefore, the phrases "in one embodiment" or "in some embodiments" appearing throughout this specification do not necessarily all refer to the same embodiment, which may be implemented alone or in combination with one or more other embodiments. In addition, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. However, those skilled in the relevant art will recognize that the present invention may be implemented without one or more specific details, or without other specific methods, components, etc. In other cases, well-known structures or operations are not shown or described in detail to avoid confusing aspects of the present invention.

[0044] Conditionally Signaling Chroma Deblocking Parameters: Embodiments of the present invention reduce signaling overhead by conditionally transmitting loop filter parameters for chroma components. For example, chroma deblocking parameters are conditionally transmitted or parsed. Some examples of chroma deblocking parameters include deblocking offset beta (β) and tC for chroma components in image or video data. In some preferred embodiments, when the current picture is a monochrome picture, the chroma deblocking parameters for the current picture are not transmitted or parsed. For example, the transmission of chroma deblocking parameters in a Picture Parameter Set (PPS) depends on the PPS-level chroma tool offset presence flag pps_chroma_tool_offsets_present_flag being transmitted in the PPS. Table 4 is an exemplary PPS syntax table showing such an example of conditionally transmitting chroma deblocking parameters in a PPS. In the exemplary PPS syntax table shown in Table 4, chroma deblocking parameters include pps_cb_beta_offset_div2, pps_cb_tc_offset_div2, pps_cr_beta_offset_div2, and pps_cr_tc_offset_div2, and these chroma deblocking parameters are allowed to be transmitted in the PPS when the PPS-level chroma tool offset present flag pps_chroma_tool_offsets_present_flag is equal to 1. This PPS-level chroma tool offset present flag pps_chroma_tool_offsets_present_flag indicates whether the picture associated with the PPS is a monochrome picture. For example, when the PPS-level chroma tool offset present flag is equal to 0, the picture associated with the PPS is a monochrome picture. In one embodiment, when the picture is not a monochrome picture, the value of the PPS-level chroma tool offset present flag can be inferred to be a number greater than 0. The PPS-level chroma tool offsets present flag equal to 1 indicates that the syntax elements associated with chroma tool offsets are allowed to be present in the PPS RBSP syntax structure, while the flag equal to 0 indicates that the syntax elements associated with chroma tool offsets are not present in the PPS RBSP syntax structure. When the syntax element ChromaArrayType is equal to 0, the value of this flag pps_chroma_tool_offsets_present_flag shall be equal to 0.The syntax element ChromaArrayType is transmitted in the corresponding sequence parameter set (SPS), which indicates whether the picture associated with the SPS is a monochrome picture. In this embodiment, when the syntax element ChromaArrayType is equal to 0, the picture associated with the SPS is a monochrome picture.

[0045] Table 4

[0046]

[0047]

[0048] In some other examples, the transmission of chroma deblocking parameters in a picture header (PH) or slice header (SH) depends on the syntax element ChromaArrayType transmitted in a sequence parameter set (SPS). Tables 5 and 6 are exemplary picture header syntax tables and slice header syntax tables, respectively, illustrating examples of conditionally transmitting chroma deblocking parameters in the PH and SH. As shown in Table 5, when the syntax element ChromaArrayType is not equal to 0, the chroma deblocking parameters ph_cb_beta_offset_div2, ph_cb_tc_offset_div2, ph_cr_beta_offset_div2, and ph_cr_tc_offset_div2 are allowed to be transmitted in the PH. The syntax element ChromaArrayType transmitted in the SPS is equal to 0, indicating that the picture corresponding to the SPS is a monochrome picture. Similarly, when the syntax element ChromaArrayType is not equal to 0, the chroma deblocking parameters slice_cb_beta_offset_div2, slice_cb_tc_offset_div2, slice_cr_beta_offset_div2 and slice_cr_tc_offset_div2 are allowed to be transmitted in the SH.

[0049] Table 5

[0050]

[0051] Table 6

[0052]

[0053] A Flag Indicating the Present of Chroma Deblocking Offset Parameters: In some embodiments of the present invention, a flag is specifically transmitted to indicate the presence of chroma deblocking offset parameters. In the present invention, chroma deblocking offset parameters are also referred to as chroma deblocking parameters. In one embodiment, this flag is transmitted when the current picture is not a monochrome picture. For example, when the current picture is not a monochrome picture, the PPS-level flag pps_chroma_deblocking_offsets_present_flag is transmitted in the PPS to indicate the presence of chroma deblocking offset parameters in the PPS. In this example, as shown in Table 7, the chroma deblocking parameters are adaptively transmitted in the PPS, depending on the value of this PPS-level flag pps_chroma_deblocking_offsets_present_flag. This PPS-level flag equal to 1 indicates that syntax elements associated with chroma deblocking offsets are allowed in the PPS RBSP syntax structure, while equal to 0 indicates that syntax elements associated with chroma deblocking offsets are not present in the PPS RBSP syntax structure. When the SPS-level syntax element ChromaArrayType is equal to 0, the value of this PPS-level pps_chroma_deblocking_offsets_present_flag shall be equal to 0. In some other examples, a PH-level flag or an SH-level flag is transmitted to indicate the deblocking offset parameters in the PH or SH, respectively. Tables 8 and 9 show the corresponding modifications for the PH and SH, respectively. In Table 8, the PH-level flag ph_chroma_deblocking_offsets_present_flag equal to 1 indicates that syntax elements associated with chroma deblocking offsets are allowed in the PH RBSP syntax structure, and the flag equal to 0 indicates that syntax elements associated with chroma deblocking offsets are not present in the PH RBSP syntax structure. When it is not present, the value of the PH-level flag shall be equal to 0. Similarly, in Table 9, the SH-level flag slice_chroma_deblocking_offsets_present_flag equal to 1 indicates that syntax elements associated with chroma deblocking offsets are allowed to be present in the slice syntax structure, while this flag equal to 0 indicates that syntax elements associated with chroma deblocking offsets are not present in the slice syntax structure. When it is not present, the value of this SH-level flag shall be equal to 0.

[0054] Table 7

[0055]

[0056] Table 8

[0057]

[0058]

[0059] Table 9

[0060]

[0061] Implicitly Inferring Chroma Deblocking Offset Parameters: According to some embodiments of the present invention, a syntax element is signaled to indicate the derivation of chroma deblocking offset parameters. This syntax element is transmitted for the current picture when the current picture is not a monochrome picture. According to some embodiments, when the current picture is not a monochrome picture, the value of this syntax element is allowed to be inferred as a number greater than 0. Depending on the value of this syntax element, the chroma deblocking offset parameters can be explicitly signaled in the PPS, PH or SH syntax structure, or implicitly inferred. For example, the chroma deblocking offset parameters can be implicitly inferred to be 0, or implicitly inferred from the corresponding luma deblocking offset parameters, or implicitly inferred from the chroma deblocking offset parameters transmitted in another syntax structure. In one example, as shown in Table 10, chroma deblocking parameters are adaptively transmitted in the PPS, depending on the syntax element pps_chroma_deblocking_offsets_present_idc. When the syntax element pps_chroma_deblocking_offsets_present_idc is equal to 2, it indicates that syntax elements associated with chroma deblocking offsets are present in the PPS RBSP. When the value of pps_chroma_deblocking_offsets_present_idc is less than 2, no syntax elements associated with chroma deblocking offsets are present in the PPS RBSP syntax structure. In some other embodiments, when the syntax element pps_chroma_deblocking_offsets_present_idc is equal to a first value, it indicates that syntax elements associated with chroma deblocking offsets are present in the PPS RBSP syntax structure; when the value of pps_chroma_deblocking_offsets_present_idc is equal to a value other than the first value, no syntax elements associated with chroma deblocking offsets are present in the PPS RBSP syntax structure. When the SPS-level syntax element ChromaArrayType is equal to 0, the value of pps_chroma_deblocking_offsets_present_idc shall be equal to 0. The syntax elements pps_cb_beta_offset_div2 and pps_cb_tc_offset_div2 specify the default deblocking parameter offsets for β and tC (divided by 2), which are applied to the chroma Cb components of slices associated with this PPS, unless the default deblocking parameters are overridden by deblocking parameter offsets present in the picture header or slice header of slices associated with this PPS.The values of pps_cb_beta_div2 and pps_cb_tc_offset_div2 shall both be between -12 and 12 (inclusive), and when not present in this PPS, the values of pps_cb_beta_offset_div2 and pps_cb_tc_offset_div2 shall both be inferred to be equal to 0 when pps_chroma_deblocking_offset_present_idc is equal to 0. In addition, the values of pps_cb_beta_offset_div2 and pps_cb_tc_offset_div2 shall be inferred to be equal to the corresponding luma deblocking parameters pps_beta_offset_div2 and pps_tc_offset_div2 when the syntax element pps_chroma_deblocking_offsets_present_idc is equal to 1. In some other embodiments, when pps_cb_beta_offset_div2 and pps_cb_tc_offset_div2 do not exist in the PPS and the syntax element pps_chroma_deblocking_offset_present_idc is equal to a first value, pps_cb_beta_offset_div2 and pps_cb_tc_offset_div2 are both inferred to be equal to 0; additionally, when the syntax element pps_chroma_deblocking_offsets_present_value is equal to a second value different from the first value, the values of pps_cb_beta_offset_div2 and pps_cb_tc_offset_div2 are inferred to be the same as the corresponding luma deblocking parameters pps_beta_offset_div2 and pps_tc_offset_div2. Similarly, the syntax elements pps_cb_beta_offset_div2 and pps_cb_tc_offset_div2 specify the default deblocking parameter offsets for β and tC (divided by 2), which are applied to the chroma Cb components of slices associated with this PPS, unless the default deblocking parameters are overridden by deblocking parameter offsets present in the picture header or slice header of slices associated with this PPS. The values of pps_cr_beta_div2 and pps_cr_tc_offset_div2 should both be between -12 and 12 (inclusive), and when not present in the PPS, the values of pps_cr_beta_offset_div2 and pps_cr_tc_offset_div2 are inferred to be equal to 0 when the syntax element pps_chroma_deblocking_offset_present_idc is equal to 0.Additionally, when the syntax element pps_chroma_deblocking_offsets_present_idc is equal to 1, the values of pps_cr_beta_offset_div2 and pps_cr_tc_offset_div2 are inferred to be the same as the corresponding luma deblocking parameters pps_beta_offset_div2 and pps_tc_offset_div2.

[0062] Table 10

[0063]

[0064] The corresponding modifications to PH and SH are described in Tables 11 and 12, respectively. In Table 11, a value of 2 for the syntax element ph_chroma_deblocking_offsets_present_idc indicates that syntax elements associated with chroma deblocking offsets are allowed in the PH RBSP syntax structure, and a value of less than 2 for the syntax element ph_chroma_deblocking_offsets_present_idc indicates that syntax elements associated with chroma deblocking offsets are not present in the PH RBSP syntax structure. When this syntax element is not present, the value of ph_chroma_deblocking_offsets_present_idc shall be equal to 0. In some other embodiments, a value of a first value for the syntax element ph_chroma_deblocking_offsets_present_idc indicates that syntax elements associated with chroma deblocking offsets are allowed in the PH RBSP syntax structure, and a value different from the first value for the syntax element ph_chroma_deblocking_offsets_present_idc indicates that syntax elements associated with chroma deblocking offsets are not present in the PH RBSP syntax structure. When this syntax element is not present, the value of ph_chroma_deblocking_offsets_present_idc shall be equal to a second value different from the first value. The two syntax elements ph_cb_beta_offset_div2 and ph_cb_tc_offset_div2 in Table 11 specify the deblocking parameter offsets for β and tC (divided by 2), which are applied to the chroma Cb component of the slice associated with the PH. The values of ph_cb_beta_offset_div2 and ph_cb_tc_offset_div2 shall both be in the range of -12 to 12, inclusive. When these two syntax elements are not present and if the syntax element ph_chroma_deblocking_offsets_present_idc is equal to 0, the values of ph_cb_beta_offset_div2 and ph_cb_tc_offset_div2 are inferred to be the same as the PPS-level syntax elements pps_cb_beta_offset_div2 and pps_cb_tc_offset_div2, respectively.Additionally, if the syntax element ph_chroma_deblocking_offsets_present_idc is equal to 1, then the values of ph_cb_beta_offset_div2 and ph_cb_tc_offset_div2 are inferred to be equal to the corresponding luma deblocking parameters, eg, luma component syntax elements ph_beta_offset_div2 and ph_tc_offset_div2, respectively. In some other embodiments, when these two syntax elements are not present and if the syntax element ph_chroma_deblocking_offsets_present_idc is equal to a first value, the values of ph_cb_beta_offset_div2 and ph_cb_tc_offset_div2 are inferred to be equal to the PPS-level syntax elements pps_cb_beta_offset_div2 and pps_cb_tc_offset_div2, respectively; and if the syntax element ph_chroma_deblocking_offsets_present_idc is equal to a second value different from the first value, the values of ph_cb_beta_offset_div2 and ph_cb_tc_offset_div2 are inferred to be equal to the corresponding luma deblocking parameters, such as the luma component syntax elements ph_beta_offset_div2 and ph_tc_offset_div2, respectively. The luma component syntax elements ph_beta_offset_div2 and ph_tc_offset_div2 are transmitted in the PH syntax structure.

[0065] Similarly, the syntax elements ph_cr_beta_offset_div2 and ph_cr_tc_offset_div2 in Table 11 specify the deblocking parameter offsets for β and tC (divided by 2), which are applied to the chroma Cr components of the slice associated with the PH. The values of ph_cr_beta_offset_div2 and ph_cr_tc_offset_div2 should both be in the range of -12 to 12, inclusive. When these two syntax elements are not present and if the syntax element ph_chroma_deblocking_offsets_present_idc is equal to 0, the values of ph_cr_beta_offset_div2 and ph_cr_tc_offset_div2 are inferred to be equal to the PPS-level syntax elements pps_cr_beta_offset_div2 and pps_cr_tc_offset_div2, respectively. Additionally, if the syntax element ph_chroma_deblocking_offsets_present_idc is equal to 1, then the values of ph_cr_beta_offset_div2 and ph_cr_tc_offset_div2 are inferred to be equal to the corresponding luma component syntax elements ph_beta_offset_div2 and ph_tc_offset_div2, respectively.

[0066] Table 11

[0067]

[0068] The corresponding modification in SH is shown in Table 12, where the value of the syntax element slice_chroma_deblocking_offsets_present_idc is equal to 2, indicating that the syntax elements associated with chroma deblocking offsets are allowed to be present in the slice syntax structure, while the value of the syntax element slice_chroma_deblocking_offsets_present_idc is less than 2, indicating that the syntax elements associated with chroma deblocking offsets are not present in the slice syntax structure. When this syntax element does not exist, the value of slice_chroma_deblocking_offsets_present_idc shall be equal to 0. In some other embodiments, the value of the syntax element slice_chroma_deblocking_offsets_present_idc is equal to 1 to indicate that syntax elements associated with chroma deblocking offsets are allowed to be present in the slice syntax structure, while the value of the syntax element slice_chroma_deblocking_offsets_present_idc is different from the first value to indicate that syntax elements associated with chroma deblocking offsets are not present in the slice syntax structure, wherein when the syntax element is not present, the value of slice_chroma_deblocking_offsets_present_idc shall be equal to the second value, which is different from the first value. The two syntax elements slice_cb_beta_offset_div2 and slice_cb_tc_offset_div2 in Table 12 indicate the deblocking parameter offsets for β and tC (divided by 2), which are applied to the chroma Cb component of the current slice. The values of slice_cb_beta_offset_div2 and slice_cb_tc_offset_div2 shall both be in the range -12 to 12, inclusive. When these two syntax elements are not present and the syntax element slice_chroma_deblocking_offsets_present_idc is equal to 0, the values of slice_cb_beta_offset_div2 and slice_cb_tc_offset_div2 are inferred to be equal to the PH level syntax elements ph_cb_beta_offset_div2 and ph_cb_tc_offset_div2, respectively.Furthermore, if the syntax element slice_chroma_deblocking_offsets_present_idc is equal to 1, then the values of slice_cb_beta_offset_div2 and slice_cb_tc_offset_div2 are inferred to be equal to the corresponding luma component syntax elements slice_beta_offset_div2 and slice_tc_offset_div2, respectively. In some other embodiments, when these two syntax elements are not present and if the syntax element slice_chroma_deblocking_offsets_present_idc is equal to a first value, then the values of slice_cb_beta_offset_div2 and slice_cb_tc_offset_div2 are inferred to be equal to the PH-level syntax elements ph_cb_beta_offset_div2 and ph_cb_tc_offset_div2, respectively; further, if the syntax element slice_chroma_deblocking_offsets_present_idc is equal to a second value different from the first value, then the values of slice_cb_beta_offset_div2 and slice_cb_tc_offset_div2 are inferred to be equal to the corresponding luma component syntax elements slice_beta_offset_div2 and slice_tc_offset_div2, respectively. Similarly, the syntax elements slice_cr_beta_offset_div2 and slice_cr_tc_offset_div2 in Table 12 indicate the deblocking parameter offsets for β and tC (divided by 2), which are applied to the chroma Cr components of the current slice. The values of slice_cr_beta_offset_div2 and slice_cr_tc_offset_div2 shall both be in the range of -12 to 12, inclusive. When these two syntax elements are not present and the syntax element slice_chroma_deblocking_offsets_present_idc is equal to 0, the values of slice_cr_beta_offset_div2 and slice_cr_tc_offset_div2 are inferred to be equal to the PH level syntax elements ph_cr_beta_offset_div2 and ph_cr_tc_offset_div2, respectively.Furthermore, if the syntax element slice_chroma_deblocking_offsets_present_idc is equal to 1, then the values of slice_cr_beta_offset_div2 and slice_cr_tc_offset_div2 are inferred to be equal to the corresponding luma component syntax elements slice_beta_offset_div2 and slice_tc_offset_div2, respectively.

[0069] Table 12

[0070]

[0071] In some embodiments of the present invention, if a syntax element transmitted in a particular syntax structure is equal to 0, then chroma deblocking parameters are not present in that particular syntax structure. In embodiments where the syntax element is transmitted in or parsed from a PPS associated with the current picture, when the value of the syntax element is 0, the chroma deblocking parameters for that PPS are not present in the PPS. When the value of the syntax element is 1, the chroma deblocking parameters for that PPS are allowed to be explicitly transmitted in or parsed from the PPS. For example, when the value of the syntax element is 0, the chroma deblocking parameters for the PPS are implicitly inferred to be equal to the corresponding PPS-level luma deblocking parameters. In embodiments where the syntax element is transmitted in or parsed from the PH associated with the current picture, when the value of the syntax element is equal to 1, chroma deblocking parameters for the PH are allowed to be explicitly transmitted in the PH or parsed from the PH, whereas when the syntax element is equal to 0, the chroma deblocking parameters for the PH are not present in the PH. For example, when the value of the syntax element is equal to 1 and the chroma deblocking parameters are not present in the PH, the chroma deblocking parameters for the current picture are implicitly inferred to be equal to the chroma deblocking parameters transmitted in the PPS associated with the current picture. When the value of the syntax element is equal to 0, the chroma deblocking parameters for the current picture are implicitly inferred to be equal to the corresponding luma deblocking parameters transmitted in the PH associated with the current picture. In embodiments where a syntax element is transmitted in or parsed from a SH associated with a current slice in a current picture, when the value of the syntax element is equal to 1, chroma deblocking parameters are allowed to be explicitly transmitted in the SH or parsed from the SH, and when the value of the syntax element is equal to 0, the chroma deblocking parameters for the SH are not present in the SH. For example, when the value of the syntax element is equal to 1 and the chroma deblocking parameters are not present in the SH, the chroma deblocking parameters of the current slice are implicitly inferred to be equal to the chroma deblocking parameters transmitted in the PH associated with the current picture. When the value of the syntax element is equal to 0, the chroma deblocking parameters of the current slice are implicitly inferred to be equal to the corresponding luma deblocking parameters transmitted in the SH associated with the current slice.

[0072] In some embodiments, the syntax elements of the deblocking filter parameters in the embodiments or examples described above can be combined with each other. For example, some changes to the syntax of tool parameters may come from a specific embodiment, while some other tool parameter syntax may come from another embodiment. In another example, tool parameter syntax from different embodiments can be combined.

[0073] Representative Flowchart for Conditionally Signaling Chroma Deblocking Parameters: Figure 6 This is a flow diagram illustrating an embodiment of an image or video encoding or decoding system that processes input data by conditionally transmitting or parsing chroma deblocking parameters. In step S602, the image or video encoding or decoding system receives input data associated with a current picture or input video data associated with a current slice within the current picture. In step S604, the image or video encoding or decoding system checks whether the current picture is a monochrome picture. For example, a PPS-level chroma tool offset presence flag for the current picture is used to indicate whether the current picture is a monochrome picture. In another example, an SPS syntax element is used to indicate whether the current picture is a monochrome picture. In step S608, if the current picture is not a monochrome picture, the image or video encoding system enables transmission of chroma deblocking parameters for the current picture or slice. For example, the chroma deblocking parameters are transmitted in a PPS, PH, or SH. In step S608, if the current picture is not a monochrome picture, the image or video decoding system conditionally parses the chroma deblocking parameters for the current picture or slice. In step S606, if the current picture is a monochrome picture, the video encoding or decoding system does not transmit or parse the chroma deblocking parameters of the current picture or current slice. In step S610, if the current picture is not a monochrome picture, a deblocking filter operation is applied to the chroma components of the current picture or current slice according to the chroma deblocking parameters. In step S612, the image or video encoding or decoding system encodes or decodes the current picture or current slice.

[0074] Representative Flowchart for Conditionally Inferring Chroma Deblocking Parameters: Figure 7A flow diagram illustrating an embodiment of image or video processing in an image or video encoding or decoding system that explicitly transmits or parses chroma deblocking parameters or implicitly infers the chroma deblocking parameters, depending on the value of a syntax element. In step S702, the image or video encoding or decoding system receives input data for a current picture or a current slice within the current picture, and in step S704, determines a syntax element for indicating the derivation of chroma deblocking parameters. For example, the syntax element is transmitted in or parsed from a PPS, PH, or SH associated with the current picture or slice. In step S706, the image or video encoding or decoding system determines, based on the value of the syntax element, whether to explicitly transmit or parse the chroma deblocking parameters for the current picture or slice, or to implicitly infer the chroma deblocking parameters. In step S708, the chroma deblocking parameters for the current picture or slice are implicitly inferred, or, in step S710, are explicitly transmitted or parsed, depending on the value of the syntax element. For example, the chroma deblocking parameters may be explicitly transmitted in a PPS, PH, or SH syntax structure or parsed therefrom, or inferred to be 0, or inferred from corresponding luma deblocking parameters or from chroma deblocking parameters transmitted in another syntax structure. In step S712, a deblocking filter operation is applied to the chroma components of the current picture or current slice based on the chroma deblocking parameters. In step S714, the image or video encoding or decoding system encodes or decodes the current picture or current slice.

[0075] Exemplary video encoders and video decoders implementing the present invention: Embodiments of the present invention can be implemented in a video encoder and / or a video decoder. For example, the disclosed methods can be implemented in the entropy coding module, inter-frame, intra-frame, or prediction module, transform module, or deblocking module of a video encoder, and / or in the entropy decoding module, inverse deblocking module, inverse transform module, inter-frame, intra-frame, or prediction module of a video decoder. Alternatively, any of the disclosed methods can be implemented as circuitry coupled to the entropy coding module, inter-frame, intra-frame, or prediction module, transform module, or deblocking module of a video encoder, and / or as circuitry coupled to the entropy decoding module, inverse deblocking module, inverse transform module, inter-frame, intra-frame, or prediction module of a video decoder to provide the information required by any module. A video encoder must follow the aforementioned syntax design to generate a valid bitstream, and a video decoder can only correctly decode the bitstream if the parsing process complies with the aforementioned syntax design. When any syntax element is skipped in the bitstream, the video encoder and decoder set the value of the syntax element to an inferred value to ensure that the encoding and decoding results match.

[0076] Figure 8An exemplary system block diagram of a video encoder 800 for implementing one or more of the various embodiments of the present invention is shown. The intra prediction module 810 provides intra predictors based on reconstructed video data for the current picture. The inter prediction module 812 performs motion estimation (ME) and motion compensation (MC) based on video data referenced from one or more other pictures to provide inter predictors. Either the intra prediction module 810 or the inter prediction module 812 utilizes a switch 814 to provide the selected predictor for the current block in the current picture to an adder 816, which subtracts the selected predictor from the original video data for the current block to form a residual. The residual for the current block is further processed by a transform module (T) 818, followed by a quantization module (Q) 820. The transformed and quantized residual signal is then encoded by an entropy encoder 834 to form a video bitstream. The transformed and quantized residual signal of the current block is processed by the inverse quantization module (IQ) 822 and the inverse transformation module (IT) 824 to restore the prediction residual. Figure 8As shown, the residual is restored by adding it back to the selected predictor at the reconstruction module (REC) 826 to produce reconstructed video data. This reconstructed video data can be stored in a reference picture buffer (Ref. Pict. Buffer) 832 and used for prediction of other pictures. Due to the encoding process, the reconstructed video data from REC 826 may be subject to various impairments. Therefore, before being stored in the reference picture buffer 832, at least one in-loop processing filter (ILPF) 828 is conditionally applied to the luma and chroma components of the reconstructed video data to further improve picture quality. A deblocking filter is an example of an ILPF 828. Syntax elements are provided to an entropy encoder 834 for incorporation into the video bitstream. In one embodiment of the present invention, chroma deblocking parameters for the current picture or the current slice within the current picture are conditionally transmitted in the video bitstream, depending on whether the current picture is a monochrome picture. In another embodiment, the chroma deblocking parameters of the current picture or current slice are explicitly transmitted or implicitly inferred according to the value of the syntax element transmitted in the PPS, PH or SH.

[0077] exist Figure 9 The Figure 8The video decoder 900 of the video encoder 800 is configured to correspond to the video decoder 900. The video bitstream encoded by the video encoder is input to the video decoder 900 and decoded by the entropy decoder 910 to parse and recover the transformed and quantized residual signal and other system information. The decoding process of the decoder 900 is similar to the reconstruction loop of the encoder 800, except that the decoder 900 only requires motion-compensated prediction in the inter-frame prediction module 914. Each block is decoded by either the intra-frame prediction module 912 or the inter-frame prediction module 914. A switch 916 selects an intra-frame predictor from the intra-frame prediction module 912 or an inter-frame predictor from the inter-frame prediction module 914 based on the decoded mode information. The inverse quantization module (IQ) 920 and the inverse transform module (IT) 922 recover the transformed and quantized residual signal. The IQ module 920 is also called the dequantization module. The recovered residual signal is reconstructed by applying it back to the predictor in the reconstruction (REC) module 918 to produce reconstructed video. The reconstructed video is further conditionally processed by at least one in-loop processing filter (ILPF) 924 to generate the final decoded video. A deblocking filter is an example of an ILPF 924. In some embodiments of the present invention, chroma deblocking parameters for the current picture or current slice are conditionally parsed based on whether the current picture is a monochrome picture. In some other embodiments, chroma deblocking parameters for the current picture or current slice within the current picture are explicitly parsed or implicitly inferred based on syntax elements parsed from the PPS, PH, or SH associated with the current picture or current slice. If the currently decoded picture is a reference picture, the reconstructed video of the currently decoded picture is also stored in a reference picture buffer (Ref.Pict.Buffer) 928 for use with later pictures in the decoding order.

[0078] Figure 8 and Figure 9The various components of the video encoder 800 and the video decoder 900 in the embodiment can be implemented by hardware components, one or more processors configured to execute program instructions stored in a memory, or a combination of hardware and processors. For example, the processor executes program instructions to control the determination of whether the current picture is a monochrome picture. The processor is equipped with one or more processing cores. In some examples, the processor executes program instructions to perform functions in certain components of the encoder 800 and the decoder 900, and the memory coupled to the processor is used to store program instructions, information corresponding to the reconstructed picture of the block and / or intermediate data during the encoding or decoding process. In some examples, the video encoder 800 can transmit information by including one or more syntax elements in the video bitstream, and the corresponding video decoder 900 obtains this information by parsing and decoding one or more syntax elements. In some embodiments, the memory includes a non-temporary computer-readable medium, such as a semiconductor or solid-state memory, a random access memory (RAM), a read-only memory (ROM), a hard disk, an optical disk, or other suitable storage medium. The memory can also be a combination of two or more non-temporary computer-readable media listed above. Figure 8 and Figure 9 As shown, the encoder 800 and the decoder 900 can be implemented in the same electronic device. Therefore, if implemented in the same electronic device, the functional components of the encoder 800 and the decoder 900 can be shared or reused. For example, Figure 8 One or more of the reconstruction module 826, the inverse transform module 824, the inverse quantization module 822, the loop processing filter 828, and the reference picture buffer 832 in the image processing module 824 may also be used as Figure 9 The reconstruction module 918, the inverse transform module 922, the inverse quantization module 920, the loop processing filter 924 and the reference picture buffer 928 in it.

[0079] Embodiments of the video processing method (for more efficient chroma deblocking parameter signaling) can be implemented in circuitry integrated into a video compression chip or program code integrated into video compression software to perform the aforementioned processing. For example, conditionally transmitting or parsing chroma deblocking parameters can be implemented in program code to be implemented on a computer processor, a digital signal processor (DSP), a microprocessor, or a field programmable gate array (FPGA). These processors can be configured to perform specific tasks according to the present invention by executing machine-readable software code or firmware code that defines specific methods embodied by the present invention.

[0080] The present invention may be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. The examples described should be considered in all respects as illustrative and not restrictive. Therefore, the scope of the present invention is indicated by the appended claims rather than the preceding description. All changes that fall within the meaning and scope of the equivalents of the claims are intended to be included within their scope of protection.

Claims

1. A method for processing an image or video in an image or video encoding and decoding system, comprising: receiving input data associated with a current picture or receiving input data associated with a current slice in the current picture; Determine whether the current image is a monochrome image; When the current picture is a monochrome picture, chroma deblocking parameters of the current picture or the current slice are not transmitted or parsed, wherein the chroma deblocking parameters include deblocking offsets beta and tC for chroma components; When the current picture is not a monochrome picture, conditionally transmitting or parsing the chroma deblocking parameters, and performing a deblocking filtering operation on the chroma components of the current picture or the current slice according to the chroma deblocking parameters; and Encode or decode the current picture or the current slice of the current picture.

2. The method according to claim 1, wherein Conditionally transmitting or parsing the chroma deblocking parameters include: When the value of the chroma tool offset existence flag is a preset value, transmitting or parsing the chroma deblocking parameter of the current picture or the current slice; and When the value of the chroma tool offset existence flag is other than the preset value, the chroma deblocking parameter of the current picture or the current slice is not transmitted or parsed.

3. The method according to claim 1, wherein The current picture is determined to be a monochrome picture according to a value of a PPS-level chroma tool offset presence flag transmitted in a picture parameter set (PPS) associated with the current picture.

4. The method according to claim 3, wherein When the syntax element ChromaArrayType transmitted in the corresponding sequence parameter set (SPS) is equal to 0, the PPS-level chroma tool offset present flag is equal to 0, and, when the PPS-level chroma tool offset present flag is equal to 0, the chroma deblocking parameters are not transmitted in the PPS or are not parsed from the PPS.

5. The method according to claim 1, wherein The chroma deblocking parameters include: pps_cb_beta_offset_div2, pps_cb_tc_offset_div2, pps_cr_beta_offset_div2 and pps_cr_tc_offset_div2.

6. The method according to claim 1, wherein According to the syntax element ChromaArrayType transmitted in the sequence parameter set (SPS), the current picture is determined to be a monochrome picture.

7. The method according to claim 6, wherein When the syntax element ChromaArrayType is equal to 0, the chroma deblocking parameters are not transmitted in the picture header (PH) associated with the current picture, and when the syntax element ChromaArrayType is not equal to 0, the chroma deblocking parameters are allowed to be transmitted in the PH.

8. The method according to claim 6, wherein When the syntax element ChromaArrayType is equal to 0, the chroma deblocking parameters are not transmitted in the slice header (SH) associated with the current slice, and when the syntax element ChromaArrayType is not equal to 0, the chroma deblocking parameters are allowed to be transmitted in the SH.

9. A method for processing an image or video in an image or video encoding and decoding system, comprising: receiving input data associated with a current picture or receiving input data associated with a current slice in the current picture; When the current picture is not a monochrome picture, determining a syntax element for indicating deriving chroma deblocking parameters for the current picture or the current slice; When the value of the syntax element is a first value, the chroma deblocking parameters of the current picture or the current slice are explicitly transmitted or parsed, wherein the chroma deblocking parameters include deblocking offsets beta and tC for chroma components; when the value of the syntax element is a value other than the first value, the chroma deblocking parameters are not transmitted, and the chroma deblocking parameters of the current picture or the current slice are implicitly inferred according to the value of the syntax element; Performing a deblocking filtering operation on the chroma component of the current picture or the current slice according to the chroma deblocking parameter; and Encode or decode the current picture or the current slice in the current picture.

10. The method according to claim 9, wherein When the current picture is not a monochrome picture, the value of this syntax element is allowed to be inferred to be a number greater than 0.

11. The method according to claim 9, wherein Depending on the value of the syntax element transmitted in the picture parameter set (PPS) or picture header (PH) associated with the current picture or the slice header (SH) associated with the current slice, the chroma deblocking parameter is explicitly transmitted in the PPS, the PH or the SH, or the chroma deblocking parameter is parsed from the PPS, the PH or the SH, or the chroma deblocking parameter is implicitly inferred.

12. The method according to claim 11, wherein When the chroma deblocking parameters are implicitly inferred, the chroma deblocking parameters are implicitly inferred to be 0, or are implicitly inferred from the luma deblocking parameters, or are implicitly inferred from another syntax structure.

13. The method according to claim 9, wherein The syntax element is transmitted in a picture parameter set (PPS) associated with the current picture or parsed from the PPS, when the value of the syntax element is equal to a first value, the chroma deblocking parameter is allowed to be explicitly transmitted in the PPS or parsed from the PPS, and when the value of the syntax element is equal to a second value, the chroma deblocking parameter is not present in the PPS, wherein the first value and the second value are different.

14. The method according to claim 13, wherein When the value of the syntax element is equal to the second value, the chroma deblocking parameters are implicitly inferred to be equal to the corresponding luma deblocking parameters in the PPS.

15. The method according to claim 9, wherein When the value of the syntax element is equal to a first value, the chroma deblocking parameter of the current picture or the current slice is allowed to be explicitly transmitted in the picture header (PH) or the slice header (SH) or the chroma deblocking parameter is parsed from the PH or the SH, and, when the value of the syntax element is equal to a second value, the chroma deblocking parameter does not exist in the PH or the SH, wherein the first value and the second value are different.

16. The method according to claim 9, wherein When the value of the syntax element is equal to a first value and the chroma deblocking parameter does not exist in the picture header PH associated with the current picture, the chroma deblocking parameter of the current picture is implicitly inferred to be equal to the chroma deblocking parameter transmitted in the picture parameter set (PPS) associated with the current picture, and, when the value of the syntax element is equal to a second value, the chroma deblocking parameter of the current picture is implicitly inferred to be equal to the corresponding luma deblocking parameter transmitted in the PH associated with the current picture, wherein the first value and the second value are different.

17. The method according to claim 9, wherein When the value of the syntax element is equal to a first value and the chroma deblocking parameter does not exist in the slice header SH associated with the current slice, the chroma deblocking parameter of the current picture is implicitly inferred to be equal to the chroma deblocking parameter transmitted in the picture header PH associated with the current picture, and, when the value of the syntax element is equal to a second value, the chroma deblocking parameter of the current picture is implicitly inferred to be equal to the corresponding luminance deblocking parameter transmitted in the SH associated with the current slice, wherein the first value and the second value are different.

18. An image or video processing device for an image or video encoding or decoding system, the device comprising a memory and a processor, wherein: The processor is configured to execute program instructions in the memory to perform the following operations: receiving input data associated with a current picture or receiving input data associated with a current slice in the current picture; Determine whether the current image is a monochrome image; When the current picture is a monochrome picture, chroma deblocking parameters of the current picture or the current slice are not transmitted or parsed, wherein the chroma deblocking parameters include deblocking offsets beta and tC for chroma components; When the current picture is not a monochrome picture, conditionally transmitting or parsing the chroma deblocking parameters, and performing a deblocking filtering operation on the chroma components of the current picture or the current slice according to the chroma deblocking parameters; and Encode or decode the current picture or the current slice of the current picture.

19. An image or video processing device for an image or video encoding or decoding system, the device comprising a memory and a processor, wherein: The processor is configured to execute program instructions in the memory to perform the following operations: receiving input data associated with a current picture or receiving input data associated with a current slice in the current picture; When the current picture is not a monochrome picture, determining a syntax element for indicating deriving chroma deblocking parameters for the current picture or the current slice; When the value of the syntax element is a first value, the chroma deblocking parameters of the current picture or the current slice are explicitly transmitted or parsed, wherein the chroma deblocking parameters include deblocking offsets beta and tC for chroma components; when the value of the syntax element is a value other than the first value, the chroma deblocking parameters are not transmitted, and the chroma deblocking parameters of the current picture or the current slice are implicitly inferred according to the value of the syntax element; Performing a deblocking filtering operation on the chroma component of the current picture or the current slice according to the chroma deblocking parameter; and Encode or decode the current picture or the current slice in the current picture.

Images