Examples of video encoding methods and apparatus and video decoding methods and apparatus are described. An example method of video processing includes performing a conversion between a video and a bitstream of the video, wherein the bitstream comprises one or more supplemental enhancement information, SEI, network abstraction layer (NAL) units according to a rule, wherein the rule specifies that, responsive to an SEI NAL unit including a non-scalable-nested SEI message of a first payload type, the SEI NAL unit is disallowed to include another SEI message of a second payload type.
Methods, systems and devices for signaling of general constraint information are described. An example method of video processing includes performing a conversion between a video comprising one or more pictures and a bitstream of the video according to a rule, wherein the rule specifies that a syntax structure in a profile-tier-level syntax structure is after a syntax element, wherein the syntax structure comprises information related to general constraint information (GCI) for the bitstream, and wherein the syntax element indicates a level to which an output layer set associated with the profile-tier-level syntax structure conforms.
H04N 19/187 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the coding unit, i.e. the structural portion or semantic portion of the video signal being the object or the subject of the adaptive coding the unit being a scalable video layer
3.
SCALABLE NESTED SEI MESSAGE HANDLING IN VIDEO SUB-BITSTREAM EXTRACTION PROCESS
Examples of video encoding methods and apparatus and video decoding methods and apparatus are described. An example method of video processing includes performing a conversion between a video including one or more layers and a bitstream of the video according to a rule, wherein the rule specifies, in a process of sub-bitstream extraction, a non-scalable nested supplementary enhancement information (SEI) message is generated by extracting an SEI message that is scalably-nested from a scalable nesting SEI message based on a first flag indicating whether the SEI message applies to specific output layer sets (OLSs) and a second flag indicating whether the SEI message applies to all subpictures or only to specific subpictures.
H04N 19/30 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using hierarchical techniques, e.g. scalability
H04N 19/119 - Adaptive subdivision aspects e.g. subdivision of a picture into rectangular or non-rectangular coding blocks
H04N 19/167 - Position within a video image, e.g. region of interest [ROI]
H04N 19/187 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the coding unit, i.e. the structural portion or semantic portion of the video signal being the object or the subject of the adaptive coding the unit being a scalable video layer
H04N 19/70 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals characterised by syntax aspects related to video coding, e.g. related to compression standards
4.
DETERMINATION OF PICTURE PARTITION MODE BASED ON BLOCK SIZE
Methods, systems, and devices for coding or decoding video wherein the picture partition mode is based on block size are described. An example method for video processing includes using a dimension of a virtual pipeline data unit (VPDU) used for a conversion between a video comprising one or more video regions comprising one or more video blocks and a bitstream representation of the video to perform a determination of whether a ternary-tree (TT) or a binary tree (BT) partitioning of a video block of the one or more video blocks is enabled, and performing, based on the determination, the conversion, wherein the dimension is equal to VSize in luma samples, wherein dimensions of the video block are CtbSizeY in luma samples, wherein VSize = min (M, CtbSizeY), and wherein M is a positive integer.
Devices, systems and methods for video processing are described. An exemplary method for video processing includes determining, for a block of a video, a quantization parameter associated with the block, coding the block of the video into a bitstream representation of the video as a palette coded block in part based on a modified value of the quantization parameter, and signaling coded information related to the quantization parameter in the bitstream representation.
H04N 19/176 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the coding unit, i.e. the structural portion or semantic portion of the video signal being the object or the subject of the adaptive coding the unit being an image region, e.g. an object the region being a block, e.g. a macroblock
H04N 19/70 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals characterised by syntax aspects related to video coding, e.g. related to compression standards
6.
MAPPING RESTRICTION FOR INTRA-BLOCK COPY VIRTUAL BUFFER
A method for video processing is described. The method includes determining, for a conversion between a current video block of a video picture of a video and a coded representation of the video, a number of reference samples in a reference region of the video picture used for predicting the current video block, based on a rule, wherein the rule specifies that the number of reference samples is limited to a certain range; and performing, based on the determining, the conversion.
H04N 19/176 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the coding unit, i.e. the structural portion or semantic portion of the video signal being the object or the subject of the adaptive coding the unit being an image region, e.g. an object the region being a block, e.g. a macroblock
H04N 19/105 - Selection of the reference unit for prediction within a chosen coding or prediction mode, e.g. adaptive choice of position and number of pixels used for prediction
7.
SAMPLE IDENTIFICATION FOR INTRA BLOCK COPY IN VIDEO CODING
A method of video processing includes maintaining, for a conversion between a current video block of a current picture of a visual media data and a bitstream representation of the visual media data, a buffer comprising reference samples from the current picture for a derivation of a prediction block of the current video block. One or more reference samples in the buffer that are marked unavailable for the derivation have values outside of a pixel value range.
H04N 19/105 - Selection of the reference unit for prediction within a chosen coding or prediction mode, e.g. adaptive choice of position and number of pixels used for prediction
8.
VIRTUAL PREDICTION BUFFER FOR INTRA BLOCK COPY IN VIDEO CODING
A method of visual media processing method includes performing a conversion between a current video block of a current picture of a visual media data and a bitstream representation of the visual media data. The conversion is based on a reference region from the current picture comprising reference samples used for deriving a prediction block of the current video block. A virtual buffer of a defined size is used for tracking availability of the reference samples for deriving the prediction block.
H04N 19/132 - Sampling, masking or truncation of coding units, e.g. adaptive resampling, frame skipping, frame interpolation or high-frequency transform coefficient masking
H04N 19/159 - Prediction type, e.g. intra-frame, inter-frame or bidirectional frame prediction
H04N 19/61 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using transform coding in combination with predictive coding
A method of video processing includes determining, for a conversion between a block that is in a video picture of a video and a bitstream representation of the video, a manner of padding a first set of samples located across boundaries of multiple video regions of the video picture for a current sample in an adaptive loop filter process. The method also includes performing the conversion according to the determining.
H04N 19/17 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the coding unit, i.e. the structural portion or semantic portion of the video signal being the object or the subject of the adaptive coding the unit being an image region, e.g. an object
H04N 19/117 - Filters, e.g. for pre-processing or post-processing
H04N 19/82 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals - Details of filtering operations specially adapted for video compression, e.g. for pixel interpolation involving filtering within a prediction loop
10.
CONSTRAINTS ON QUANTIZED RESIDUAL DIFFERENTIAL PULSE CODE MODULATION REPRESENTATION OF CODED VIDEO
Video coding and decoding methods are described. In example method includes determining that a differential coding mode is applicable to a conversion between a current video block of a video and a bitstream representation of the current video block, and performing, based on the determining, the conversion between the current video block and the bitstream representation of the current video block using the differential coding mode according to an implementation rule, where, in the differential coding mode, the current video block is represented in the bitstream representation using a difference between a quantized residual of an intra prediction of the current video block and a prediction of the quantized residual, and where, in the differential coding mode, the difference between the quantized residual and the prediction of the quantized residual is represented using a differential pulse coding modulation (DPCM) representation.
H04N 19/176 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the coding unit, i.e. the structural portion or semantic portion of the video signal being the object or the subject of the adaptive coding the unit being an image region, e.g. an object the region being a block, e.g. a macroblock
H04N 19/50 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using predictive coding
H04N 19/61 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using transform coding in combination with predictive coding
H04N 19/70 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals characterised by syntax aspects related to video coding, e.g. related to compression standards
A method for visual mediaprocessing, comprising: computing, during a conversion between a current video block of visual media data and a bitstream representation of the current video block, a cross-component linear model (CCLM) and/or a chroma residual scaling (CRS) factor for the current video block based, at least in part, on neighboring samples of a corresponding luma block which covers a top-left sample of a collocated luma blockassociated with the current video block, wherein one or more characteristics of the current video block are used for identifying the corresponding luma block.
H04N 19/593 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using predictive coding involving spatial prediction techniques
12.
RESTRICTION ON APPLICABILITY OF CROSS COMPONENT MODE
A method for visual media processing, comprising performing a conversion between a current chroma video block of visual media data and a bitstream representation of the current chroma video block, wherein, during the conversion, a chroma residual of the current chroma video block is scaled based on a scaling coefficient, wherein the scaling coefficient is derived at least based on luma samples located in predefined positions.
A method for visual media processing, comprising performing a conversion between a current chroma video block of visual media data and a bitstream representation of the current chroma video block, wherein, during the conversion, a chroma residual of the current chroma video block is scaled based on a scaling coefficient, wherein the scaling coefficient is derived at least based on luma samples located in predefined positions.
Devices, systems and methods for coefficient coding in transform skip mode are described. An exemplary method for video processing includes determining, for encoding one or more video blocks in a video region of a visual media data into a bitstream representation of the visual media data, a maximum allowed dimension up to which a current video block of the one or more video blocks is allowed to be encoded using a transform skip mode such that a residual of a prediction error between the current video block and a reference video block is represented in the bitstream representation without applying a transform; and including a syntax element indicative of the maximum allowed dimension in the bitstream representation.
H04N 19/176 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the coding unit, i.e. the structural portion or semantic portion of the video signal being the object or the subject of the adaptive coding the unit being an image region, e.g. an object the region being a block, e.g. a macroblock
H04N 19/70 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals characterised by syntax aspects related to video coding, e.g. related to compression standards
15.
CHROMA CODING MODE DETERMINATION BASED ON MATRIX-BASED INTRA PREDICTION
Devices, systems and methods for digital video coding, which includes matrix-based intra prediction methods for video coding, are described. In a representative aspect, a method for video processing includes performing a first determination that a luma video block of a video is coded using a matrix based intra prediction (MIP) mode in which a prediction block of the luma video block is determined by performing, on previously coded samples of the video, a boundary downsampling operation, followed by a matrix vector multiplication operation, and selectively followed by an upsampling operation, performing, based on the first determination, a second determination about a chroma intra mode to be used for a chroma video block associated with the luma video block, and performing, based on the second determination, a conversion between the chroma video block and a bitstream representation of the chroma video block.
H04N 19/593 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using predictive coding involving spatial prediction techniques
16.
MOST PROBABLE MODE LIST CONSTRUCTION FOR MATRIX-BASED INTRA PREDICTION
Devices, systems and methods for digital video coding, which includes matrix-based intra prediction methods for video coding, are described. In a representative aspect, a method for video processing includes generating, for a conversion between a current video block of a video and a coded representation of the current video block, a most probable mode (MPM) list based on a rule, where the rule is based on whether a neighboring video block of the current video block is coded with a matrix based intra prediction (MIP) mode, and performing the conversion between the current video block and the coded representation of the current video block using the MPM list, where the conversion applies a non-MIP mode to the current video block, and where the non-MIP mode is different from the MIP mode.
A method of video processing is provided to comprise: maintaining, prior to a conversion between a current video block of a video region and a coded representation of the video, at least one history-based motion vector prediction (HMVP) table, wherein the HMVP table includes one or more entries corresponding to motion information of one or more previously processed blocks; and performing the conversion using the at least one HMVP table; and wherein the motion information of each entry is configured to include interpolation filter information for the one or more previously processed blocks, wherein the interpolation filter information indicates interpolation filters used for interpolating prediction blocks of the one or more previously processed blocks.
Devices, systems and methods for video processing are described. In an exemplary aspect, a method for video processing includes encoding a video unit of a video as an encoded video unit; generating reconstruction samples from the encoded video unit; performing a clipping operation on the reconstruction samples, wherein a clipping parameter used in the clipping operation is a function of a clipping index and a bit-depth of the reconstruction samples or a bit-depth of samples of the video unit; applying a non-linear adaptive loop filter to an output of the clipping operation; and generating a coded representation of the video using the encoded video unit.
H04N 19/80 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals - Details of filtering operations specially adapted for video compression, e.g. for pixel interpolation
19.
IMPROVED WEIGHTING PROCESSING OF COMBINED INTRA-INTER PREDICTION
The present application relates to improved weighting processing of combined intra-inter prediction. A method for processing video includes: determining, during a conversion between a current video block, which is coded in a combined intra and inter prediction (CIIP) mode, of a video and a bitstream representation of the current video block, a weight pair comprising a first weight for a first prediction result of the current video block and a second weight for a second prediction result of the current video block, based on one or more neighboring video blocks to the current video block, wherein the first prediction result is generated by an intra prediction mode and the second prediction result is generated by an inter prediction mode; and determining a prediction result of the current block based on a weighted sum of the first prediction result and the second prediction result.
A video processing method is provided to comprise: performing a conversion between a coded representation of a video comprising one or more video regions and the video, wherein the coded representation includes reshaping model information applicable for in loop reshaping (ILR) of some of the one or more video regions, wherein the reshaping model information provides information for a reconstruction of a video unit of a video region based on a representation in a first domain and a second domain and/or scaling chroma residue of a chroma video unit, and wherein the reshaping model information comprises a parameter set that comprises a syntax element specifying a difference between an allowed maximum bin index and a maximum bin index to be used in the reconstruction, and wherein the parameter is in a range.
H04N 19/136 - Incoming video signal characteristics or properties
H04N 19/176 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the coding unit, i.e. the structural portion or semantic portion of the video signal being the object or the subject of the adaptive coding the unit being an image region, e.g. an object the region being a block, e.g. a macroblock
H04N 19/30 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using hierarchical techniques, e.g. scalability
H04N 19/82 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals - Details of filtering operations specially adapted for video compression, e.g. for pixel interpolation involving filtering within a prediction loop
A method for video processing is provided. The method includes determining, for a conversion between a current video block of a video that is a chroma block and a coded representation of the video, parameters of a cross-component linear model (CCLM) based on two or four chroma samples and/or corresponding luma samples; and performing the conversion based on the determining.
H04N 19/186 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the coding unit, i.e. the structural portion or semantic portion of the video signal being the object or the subject of the adaptive coding the unit being a colour or a chrominance component
H04N 19/61 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using transform coding in combination with predictive coding
22.
INDEPENDENT CODING OF PALETTE MODE USAGE INDICATION
Devices, systems and methods for palette mode coding are described. An exemplary method for video processing includes performing a conversion between a block of a video region of a video and a bitstream representation of the video. The bitstream representation is processed according to a first format rule that specifies whether a first indication of usage of a palette mode is signaled for the block and a second format rule that specifies a position of the first indication relative to a second indication of usage of a prediction mode for the block.
H04N 19/503 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using predictive coding involving temporal prediction
Devices, systems and methods for palette mode coding are described. An exemplary method for video processing includes determining, for a conversion between a block of a video region in a video and a bitstream representation of the video, a prediction mode based on one or more allowed prediction modes that include at least a palette mode of the block. An indication of usage of the palette mode is determined according to the prediction mode. The method also includes performing the conversion based on the one or more allowed prediction modes.
H04N 19/186 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the coding unit, i.e. the structural portion or semantic portion of the video signal being the object or the subject of the adaptive coding the unit being a colour or a chrominance component
24.
NEIGHBOURING SAMPLE SELECTION FOR INTRA PREDICTION
A method for video processing is provided. The method includes determining, for a conversion between a current video block of a video that is a chroma block and a coded representation of the video, parameters of cross-component linear model (CCLM) prediction mode based on chroma samples that are selected based on W available above-neighbouring samples, W being an integer; and performing the conversion based on the determining.
A method for video processing is provided to include performing a conversion between a current video block of a video region of a video and a coded representation of the video, wherein the conversion uses a coding mode in which the current video block is constructed based on a first domain and a second domain and/or chroma residue is scaled in a luma-dependent manner, and wherein a parameter set in the coded representation comprises parameter information for the coding mode.
H04N 19/82 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals - Details of filtering operations specially adapted for video compression, e.g. for pixel interpolation involving filtering within a prediction loop
H04N 19/186 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the coding unit, i.e. the structural portion or semantic portion of the video signal being the object or the subject of the adaptive coding the unit being a colour or a chrominance component
26.
BUFFER MANAGEMENT FOR INTRA BLOCK COPY IN VIDEO CODING
A method of visual media processing includes determining a size of a buffer to store reference samples for prediction in an intra block copy mode; and performing a conversion between a current video block of visual media data and a bitstream representation of the current video block, using the reference samples stored in the buffer, wherein the conversion is performed in the intra block copy mode which is based on motion information related to a reconstructed block located in same video region with the current video block without referring to a reference picture.
H04N 19/15 - Data rate or code amount at the encoder output by monitoring actual compressed data size at the memory before deciding storage at the transmission buffer
H04N 19/115 - Selection of the code volume for a coding unit prior to coding
H04N 19/122 - Selection of transform size, e.g. 8x8 or 2x4x8 DCT; Selection of sub-band transforms of varying structure or type
H04N 19/159 - Prediction type, e.g. intra-frame, inter-frame or bidirectional frame prediction
H04N 19/176 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the coding unit, i.e. the structural portion or semantic portion of the video signal being the object or the subject of the adaptive coding the unit being an image region, e.g. an object the region being a block, e.g. a macroblock
A method for video processing is provided to include performing, for a conversion between a current video block of a video and a coded representation of the video, a motion information refinement process based on samples in a first domain or a second domain; and performing the conversion based on a result of the motion information refinement process, wherein, during the conversion, the samples are obtained for the current video block from a first prediction block in the first domain using an unrefined motion information, at least a second prediction block is generated in the second domain using a refined motion information used for determining a reconstruction block, and reconstructed samples of the current video block are generated based on the at least the second prediction block.
A method for video processing is provided. The method includes performing downsampling on chroma and luma samples of a neighboring block of the current video block; determining, for a conversion between a current video block of a video that is a chroma block and a coded representation of the video, parameters of cross-component linear model (CCLM) based on the downsampled chroma and luma samples obtained from the downsampling; applying the CCLM on luma samples located in a luma block corresponding to the current video block to derive prediction values of the current video block; and performing the conversion based on the prediction values.
H04N 19/50 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using predictive coding
H04N 19/186 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals using adaptive coding characterised by the coding unit, i.e. the structural portion or semantic portion of the video signal being the object or the subject of the adaptive coding the unit being a colour or a chrominance component
29.
PULSE CODE MODULATION TECHNIQUE IN VIDEO PROCESSING
Devices, systems and methods for digital video coding, which include pulse code modulation techniques, are described. An exemplary method for video processing includes determining, for a current block of video, that at least one of a first coding mode in which pulse code modulation is used or a second coding mode in which multiple reference line based intra prediction is used is enabled, and performing, based on the first coding mode or the second coding mode, a conversion between the current block and a bitstream representation of the video, wherein a first indication indicative of use of the first coding mode and/or a second indication indicative of use of the second coding mode are included in the bitstream representation according to an ordering rule.
A method of video processing is provided to include: maintaining a set of tables, wherein each table includes motion candidates and each motion candidate is associated with corresponding motion information; updating a motion candidate list based on motion candidates in one or more tables using a pruning operation on the motion candidates; and performing a conversion between a first video block and a bitstream representation of a video including the first video block using the constructed motion candidate list.
H04N 19/52 - Processing of motion vectors by encoding by predictive encoding
H04N 19/70 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals characterised by syntax aspects related to video coding, e.g. related to compression standards
A method of video decoding is provided to include maintaining tables, wherein each table includes a set of motion candidates and each motion candidate is associated with corresponding motion information; and performing a conversion between a first video block and a bitstream representation of a video including the first video block, the performing of the conversion including using at least some of the set of motion candidates as a predictor to process motion information of the first video block.
H04N 19/52 - Processing of motion vectors by encoding by predictive encoding
H04N 19/70 - Methods or arrangements for coding, decoding, compressing or decompressing digital video signals characterised by syntax aspects related to video coding, e.g. related to compression standards