Abstract: A method for luma-based chroma intra-prediction in a video encoder or a video decoder is provided that includes filtering reconstructed neighboring samples of a reconstructed down sampled luma block, computing parameters ? and ? of a linear model using the filtered, reconstructed neighboring samples of the reconstructed down sampled luma block and reconstructed neighboring samples of a corresponding chroma block, wherein the linear model is PredC[x,y]=?·RecL?[x,y]+?, wherein x and y are sample coordinates, PredC is predicted chroma samples, and RecL? is samples of the reconstructed down sampled luma block, and computing samples of a predicted chroma block from corresponding samples of the reconstructed down sampled luma block using the linear model and the parameters.

Abstract: Methods, devices, and systems related to video processing are disclosed. In one example aspect, a method of video processing includes performing a conversion between a block of a current picture of a video and a coded representation of the video using an intra-subblock partitioning (ISP) mode. A prediction is determined for each sub-partition using an intra-prediction process based on samples in the current picture using the ISP mode. The block is partitioned into multiple sub-partitions including a first sub-partitions having a same top-left corner position as a top-left corner position of the block.

Abstract: A method for decoding an image according to the present invention comprises the steps of: receiving and decoding MPM index information for indicating an MPM candidate which is to be used as an intra prediction mode of a current block; generating an MPM candidate list containing a plurality of MPM candidates for the current block; determining the MPM candidate indicated by the decoded MPM index information as the intra prediction mode of the current block, among the plurality of the MPM candidates which constitute the MPM candidate list; and generating a prediction block corresponding to the current block by performing intra prediction for the current block based on the determined intra prediction mode.

Abstract: 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 and a bitstream representation of the video. The bitstream representation is processed according to a format rule that specifies a first indication of usage of a palette mode and a second indication of usage of an intra block copy (IBC) mode are signaled dependent of each other.

Abstract: Systems, methods and apparatus for video processing are described. The video processing may include video encoding, video decoding, or video transcoding. One example method of video processing includes performing a conversion between a video including one or more pictures and a bitstream of the video according to a format rule. The format rule specifies that a first syntax element that indicates whether motion vector difference for a particular reference picture list (RPL) is indicated is conditionally included in the bitstream based on (i) whether a second syntax element indicating whether an RPL information is included in a picture header and/or (ii) a number of reference pictures in the particular RPL in case that the RPL information is present in the picture header.

Abstract: A decoder includes circuitry which, in operation, parses a first flag indicating whether a CCALF (cross component adaptive loop filtering) process is enabled for a first block located adjacent to a left side of a current block; parses a second flag indicating whether the CCALF process is enabled for a second block located adjacent to an upper side of the current block; determines a first index associated with a color component of the current block; and derives a second index indicating a context model, using the first flag, the second flag, and the first index. The circuitry, in operation, performs entropy decoding of a third flag indicating whether the CCALF process is enabled for the current block, using the context model indicated by the second index; and performs the CCALF process on the current block in response to the third flag indicating the CCALF process is enabled for the current block.

Abstract: A decoding method is disclosed that comprises: determining whether a current block of a picture extends beyond a boundary of the picture; determining for each split mode of a plurality of split modes whether said current block is allowed to undergo splitting according to said split mode by checking whether at least one of the split line is co-located with one of the picture border or whether the size of the block part inside the picture along the picture boundary is a multiple of a minimum block size; decoding from a bitstream a current split mode of the current block responsive to the allowed split modes; and decoding the current block according to the current split mode.

Abstract: A method of video decoding in a decoder is provided. A first template magnitude of a first transform coefficient in a specific frequency region of the transform block is determined. The first template magnitude is a first single value representing magnitudes of a first local template of the first transform coefficient. A first context model is identified for coding the syntax element of the first transform coefficient, the first context model being shared with at least a second transform coefficient in the specific frequency region of the transform block, a second template magnitude of the second transform coefficient having a second single value that belongs to a first subinterval. A first bin of the syntax element of the first transform coefficient and a second bin of the syntax element of the second transform coefficient is determined, from the coded bits, based on the first context model.

Abstract: Aspects of the disclosure provide a method and an apparatus for video decoding. The apparatus includes processing circuitry receiving prediction information of a plurality of blocks in a current picture from a coded video bitstream. The processing circuitry determines, based on the prediction information, whether at least one of a decoder-side motion vector refinement (DMVR) mode or a bi-directional optical flow (BDOF) mode is allowed for the plurality of blocks. If the DMVR mode or the BDOF mode is allowed for the plurality of blocks, the processing circuitry determines that a plurality of merge with motion vector difference (MMVD) merge flags indicating whether a MMVD mode is applied to the plurality of blocks, respectively, is inferred as false for the plurality of blocks. If the plurality of MMVD merge flags is inferred as false, the processing circuitry reconstructs each block in the plurality of blocks without applying the MMVD mode.

Abstract: According to the disclosure of the present document, weight index information for sub-block merge candidates of a current block can be derived and coding efficiency can be increased.

Abstract: According to the disclosure of the present document, information regarding ALF filter coefficients may be encoded/decoded by fixed order-based exponential golomb coding. In addition, information regarding a fixed filter in ALF may be binarized by fixed-length coding. Accordingly, signaling efficiency can be increased, and coding complexity can be decreased.

Abstract: The present invention relates to an image information decoding method. The decoding method includes receiving a bit stream including a Network Abstraction Layer (NAL) unit that includes information related to encoded image, and parsing a NAL unit header of the NAL unit. The NAL unit header may not include 1 bit flag information that represents whether a picture is a non-reference picture or a reference picture in the entire bit stream during encoding.

Abstract: The present invention relates to an inter-layer prediction method and to an apparatus implementing the method. The method may comprise the steps of generating a first block constituted by the value obtained by up-sampling the reconstruction value of a reference block of a reference layer corresponding to the current block; generating a second block constituted by a prediction value derived from intra-prediction mode of the current block; and generating a prediction block of the current block by combining sample values of the first block and the second block. Thus, intra-prediction on the current layer can be performed using the intra-prediction mode information of another layer.

Abstract: The present invention relates to an intra-prediction method and to an encoder and decoder using same. The intra-prediction method according to one embodiment of the present invention comprises the steps of: deriving a prediction mode of a current block; and generating a prediction block with respect to the current block on the basis of the prediction mode of the current block. When the prediction mode of the current block is an intra-angular prediction mode, values of boundary samples from among left boundary samples and upper boundary samples of the prediction block, which are not positioned in a prediction direction of the intra-angular prediction mode, are derived on the basis of reference samples positioned in the prediction direction of the intra-angular prediction mode, and on the basis of adjacent reference samples.

Abstract: A method and an apparatus for parallel encoding and decoding of moving picture data are provided. The method includes decoding, from a bitstream, a syntax element indicating that a picture can be decoded using wavefront parallel processing and decoding encoded data of the picture. The step of decoding encoded data of the picture includes for a first coding block of a current CTU row encoded in a palette mode, predicting a palette table for the first coding block by using palette data from a first CTU of a previous CTU row and decoding the first coding block in the palette mode using the palette table predicted for the first coding block.

Abstract: Procedures, methods, architectures, apparatuses, systems, devices, and computer program products directed to improved linear model estimation for template-based video coding are provided. Included therein is a method comprising determining minimum and maximum (“min/max”) values of luma and chroma samples neighboring a coding block, wherein the min/max chroma values correspond to the min/max luma values; determining a first linear model parameter of a template-based video coding technique (i) based on a single look-up table and the min/max chroma values and (ii) at a precision no greater than 16 bits; determining a second linear model parameter of the template-based video coding technique (i) based on the first linear model parameter and the minimum chroma and luma values and (ii) at a precision no greater than 16 bits; and predicting chroma samples of the coding block based on reconstructed luma samples of the coding block and the first and second linear model parameters.

Abstract: Provided is an image encoding method. The method includes: determining an intra prediction mode of an encoding block, and constructing a first prediction value of the encoding block according to the intra prediction mode; determining a filtering parameter according to the first prediction value and an original value of the encoding block, where the filtering parameter includes a filtering indication parameter; in a case where the filtering indication parameter indicates performing filtering processing on the first prediction value, performing the filtering processing on the first prediction value to obtain an intra prediction value; calculating a prediction difference parameter according to a difference between the original value of the encoding block and the intra prediction value; and encoding the intra prediction mode, the filtering parameter, and the prediction difference parameter, and writing encoded bits into a bitstream.

Abstract: A method for decoding/encoding an image signal with the decoding/encoding apparatus according to the present invention may comprise the steps of: generating a first prediction sample of a current block, determining a weight prediction parameter set of the current block by using a predetermined reference region, the reference region being a region reconstructed before the current block and including a neighboring region spatially adjacent to the current block, and generating a second prediction sample of the current block by applying the weight prediction parameter set to the first prediction sample. Herein, the neighboring region is determined based on information signaled from a bitstream, and the information specifies a position of the neighboring region and is used to determine the weight prediction parameter set.

Abstract: A method for controlling block intra prediction is provided for a decoder. The method includes: obtaining a coded video bitstream; decoding, prediction information of a current coding unit (CU) in a segment of a current picture from the coded video bitstream; determining, according to the prediction information, a prediction type of a chroma coding block (CB) of the current CU, the prediction type being intra prediction or inter prediction; and reconstructing the chroma CB according to the prediction information, where a width of any reconstructed chroma CB intra-predicted from the coded video bitstream is greater than 2.

Abstract: In a decoding apparatus configured to perform decoding processing in parallel using N arithmetic decoding units and M image decoding units on a plurality of slices, each slice being composed of at least one encoding block line, the N arithmetic decoding units start arithmetic decoding processing in sequence at time intervals corresponding to slice sizes on a stream that satisfies a condition that a difference between a total number of encoding block lines included in any N consecutive slices and a total number of encoding block lines included in N consecutive slices different from the any N consecutive slices is 1 or less, and a condition that a code amount of each slice is less than a predetermined upper limit code amount.

Abstract: In performing image encoding/decoding, decoding of an image is performed by deriving an intra prediction mode for a current block, decoding at least one original sample that is present in a rightmost column and a bottommost row (a bottom row) of the current block, constructing a reference sample by using the at least one decoded original sample and performing intra prediction on the current block by using the constructed reference sample.

Abstract: A method and an apparatus for parallel encoding and decoding of moving picture data are provided. The method includes decoding, from a bitstream, a syntax element indicating that a picture can be decoded using wavefront parallel processing and decoding encoded data of the picture. The step of decoding encoded data of the picture includes for a first coding block of a current CTU row encoded in a palette mode, predicting a palette table for the first coding block by using palette data from a first CTU of a previous CTU row and decoding the first coding block in the palette mode using the palette table predicted for the first coding block.

Abstract: A method of and an apparatus for controlling intra prediction for decoding of a video sequence are provided. The method may include based on a reference line index signaling a first reference line nearest to a coding unit, among a plurality of reference lines adjacent to the coding unit, applying intra smoothing on one or more first reference lines comprising the first reference line, among the plurality of reference lines, and based on the intra smoothing being applied on the one or more first reference lines, applying a position-dependent intra prediction combination (PDPC) on one or more third reference lines comprising the first reference line, among the plurality of reference lines, while preventing application of the PDPC on one or more fourth reference lines other than the one or more third reference lines, among the plurality of reference lines.

Abstract: Disclosed in the implementations of the present disclosure are a mapping method, an encoder, a decoder, and a computer storage medium. The method may include: determining an intra prediction mode used at the time of encoding or decoding a current block; mapping, if the intra prediction mode is a MIP mode, the MIP mode to a first non-MIP mode; and mapping, if the intra prediction mode is a non-MIP mode, the non-MIP mode to a second MIP mode.

Abstract: An image processing method includes obtaining statistics information of a block of an image frame, determining whether the statistics information satisfies a condition, and disabling cross-component filtering (CCF) for the block in response to the statistics information satisfying the condition.

Abstract: A video coding device may be configured to perform transform data coding according to one or more of the techniques described herein.

Abstract: A device may be configured to signal range extension profile information for coded video according to one or more of the techniques described herein.

Abstract: A method for decoding an image by a decoding device, according to the present document, comprises the steps of: acquiring image information; and generating a reconstructed picture on the basis of the image information.

Abstract: A method and an apparatus for parallel encoding and decoding of moving picture data are provided. The method includes decoding, from a bitstream, a syntax element indicating that a picture can be decoded using wavefront parallel processing and decoding encoded data of the picture. The step of decoding encoded data of the picture includes for a first coding block of a current CTU row encoded in a palette mode, predicting a palette table for the first coding block by using palette data from a first CTU of a previous CTU row and decoding the first coding block in the palette mode using the palette table predicted for the first coding block.

Abstract: A method and an apparatus for parallel encoding and decoding of moving picture data are provided. The method includes decoding, from a bitstream, a syntax element indicating that a picture can be decoded using wavefront parallel processing and decoding encoded data of the picture. The step of decoding encoded data of the picture includes for a first coding block of a current CTU row encoded in a palette mode, predicting a palette table for the first coding block by using palette data from a first CTU of a previous CTU row and decoding the first coding block in the palette mode using the palette table predicted for the first coding block.

Abstract: The present disclosure provides a video encoding and decoding method and a video encoding and decoding device. The method includes: partitioning the current block into a first triangular sub-block and a second triangular sub-block when a current block satisfies specific conditions for enabling a geometric partitioning mode with triangular partition and the geometric partitioning mode with triangular partition is determined to be enabled; obtaining first target motion information of the first triangle sub-block and second target motion information of the second triangle sub-block, wherein the first target motion information is different from the second target motion information; and performing an encoding processing or a decoding processing on the current block based on the first target motion information and the second target motion information.

Abstract: Exemplary video processing methods and apparatuses for encoding or decoding a current block by bi-directional prediction are disclosed. L0 and L1 reference blocks are determined for the current block, and a motion vector refinement is applied to refine the L0 and L1 reference blocks using a motion estimation search performed on each processing unit in the current block. A bi-directional optical flow operation is early terminated according to a cost of each processing unit in the current block. The processing units for cost calculation in the motion vector refinement and the bi-directional optical flow early termination are unified. The bi-directional optical flow operation is applied to the current block to further refine the L0 and L1 reference blocks if the bi-directional optical flow operation is not early terminated. A final inter predictor is derived from the refined L0 and L1 reference blocks for encoding or decoding the current block.

Abstract: Techniques related to accelerated video enhancement using deep learning selectively applied based on video codec information are discussed. Such techniques include applying a deep learning video enhancement network selectively to decoded non-skip blocks that are in low quantization parameter frames, bypassing the deep learning network for decoded skip blocks in low quantization parameter frames, and applying non-deep learning video enhancement to high quantization parameter frames.

Abstract: An image decoding method according to the present disclosure comprises deriving a first candidate intra prediction mode based on a first neighboring block of a current block; deriving a second candidate intra prediction mode based on a second neighboring block of the current block; constructing MPM (Most Probable Mode) list of the current block based on the first candidate intra prediction mode and the second candidate intra prediction mode; deriving an intra prediction mode for the current block based on the MPM list; and generating a prediction sample for the current block based on the intra prediction mode, wherein the first neighboring block is a left neighboring block located at the lowermost side among neighboring blocks adjacent to a left boundary of the current block, and wherein the second neighboring block is an upper neighboring block located at the rightmost side among neighboring blocks adjacent to an upper boundary of the current block.

Abstract: 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, multiple sets of parameters, wherein each set of parameters defines a cross-component linear model (CCLM) and is derived from a corresponding group of chroma samples at corresponding chroma sample positions; determining, based on the multiple sets of parameters, parameters for a final CCLM; and performing the conversion based on the final CCLM.

Abstract: A media client ascertains a plurality of matching points between (i) query fingerprints representing a media stream being received by the client and (ii) reference fingerprints, each identified matching point defining a respective match between a query fingerprint that is timestamped with client time defined according to a clock of the client and a reference fingerprint that is timestamped with true time defined according to a timeline within a known media stream. Further, the client performs linear regression based on the timestamps of the ascertained plurality of matching points, to establish a mapping between true time and client time. The client then uses the established mapping as a basis to determine a client-time point at which the client should perform an action with respect to media stream being received by the client. And the client performs the action at the determined client-time point.

Abstract: The method for decoding an image by a decoding device according to the present document may comprise the steps of: acquiring image information comprising partitioning information for a current block; determining, on the basis of the size of the current block, whether to partition the current block; partitioning the current block into subblocks on the basis of the partitioning information, if it is determined that the current block is to be partitioned, and decoding the subblocks; and not partitioning the current block, if it is determined that the current block is not to be partitioned, and decoding the current block, wherein, if the current block is a chroma block, and the size of the current block is at most the minimum size of a chroma block, then it is determined that the current block is not to be partitioned.

Abstract: A video coding mechanism is disclosed. The mechanism includes receiving a video signal partitioned into a chroma block and a first neighboring luma block. The mechanism also includes encoding prediction information for chroma samples of the chroma block into a bitstream. The prediction information for the chroma samples is determined via intra-prediction based on down-sampled neighboring luma samples. The down-sampled neighboring luma samples are generated from a single row of luma samples from the first neighboring luma block. A bitstream including the prediction information for the chroma samples is transmitted to support decoding and display of the chroma samples.

Abstract: An intra prediction method comprises receiving input data of a current block in a current picture, deriving reference samples of the current block from boundary samples, selecting a matrix for the current block, generating intermediate predicted samples by multiplying the reference samples and the matrix, and clipping the intermediate predicted samples before up-sampling. The intra prediction method further comprises performing an up-sampling process on the clipped intermediate predicted samples to generate predicted samples for the current block, and encoding or decoding the current block according to the predicted samples of the current block.

Abstract: A video image processing method includes binarizing a chrominance prediction mode of the image block of a to-be-encoded/decoded image to obtain a bit string, the bit string including two adjacent bits, the to-be-encoded/decoded image being permitted to use a CCLM and/or a regular intra-frame chrominance prediction mode, and the CCLM including a first mode, a second mode, and a third mode, and using mutually independent probability models to encode/decode a first bit and a second bit. The first bit of the adjacent bits indicates whether the CCLM is used, the second bit indicates whether to use the first mode of the CCLM when the first bit indicates to use the CCLM, the third bit indicates whether the second mode or the third mode of the CCLM is used when the second bit indicates that the first mode of the CCLM is not used.

Abstract: A method for cloud gaming. The method including receiving one or more encoded slices of a video frame at a client, wherein the video frame was generated at a server while executing a video game, and encoded by an encoder at the server into the one or more encoded slices. The method including decoding a first encoded slice at a decoder of the client before fully receiving the one or more encoded slices of the video frame.

Abstract: A video coder may code a block of video data using an intra prediction mode determined from a most probable mode list. The video coder may construct a general most probable mode list containing N entries, wherein the N entries of the general most probable mode list are intra prediction modes, and wherein a planar mode is an ordinal first entry in the general most probable mode list, construct a primary most probable mode list from a first Np entries in the general most probable mode list, where Np is less than N, and construct a secondary most probable mode list from a remaining (N?Np) entries in the general most probable mode list. The video coder may then determine a current intra prediction mode for a current block of video data using the primary most probable mode list or the secondary most probable mode list.

Abstract: An example device for decoding video data includes one or more processors implemented in circuitry and configured to: decode a coding tree unit (CTU) of video data, the CTU including a luminance (luma) block and a chrominance (chroma) block, to produce a decoded luma block and a decoded chroma block; determine that a chroma sample of the decoded chroma block is on a first side of an adaptive loop filter (ALF) virtual boundary and that a co-located luma sample of the decoded luma block is on a second side of the ALF virtual boundary, the co-located luma sample being co-located with the chroma sample, the first side being different than the second side; and in response to determining that the chroma sample is on the first side and the luma sample is on the second side, disable cross-component adaptive loop filtering (CC-ALF) for the chroma sample.

Abstract: A video encoder or decoder processes portions of video using intra coding and with variable block shapes. Under the general aspects, intra prediction directions are adapted to the block shape or aspect ratio. The general aspects described adaptively replace several conventional angular intra prediction modes with wide-angle intra prediction modes for non-square blocks. The total number of angular directions for any block can remain the same as in prior video coding standards or can be reduced or expanded. To keep the same number of prediction directions, directions along a shorter rectangular edge of a target block are removed but replaced with addition directions along the longer edge of the rectangular target block. For directions with wide angles, reference sample smoothing is performed. Signaling can be provided to inform a corresponding decoder regarding the prediction modes and directions.

Abstract: This invention suppresses degradation of subjective image quality while improving the coding efficiency of residual coefficients of two chroma components. To this, an image coding device that codes image data constituted by one luma component and two chroma components according to the invention, comprises quantizing unit that performs an orthogonal transform on each of components of a block obtained by dividing an image to be coded, and quantizes transform coefficients of each of the components obtained from the orthogonal transform; and coding unit that codes residual coefficients obtained by the quantizing unit, wherein when coding the transform coefficients of the orthogonal transform of the two chroma components in an integrated manner, the coding unit quantizes transform coefficients of the orthogonal transform obtained from the integration using a predetermined quantization matrix, and codes residual coefficients obtained from the quantizing.

Abstract: Techniques related to improved visual quality for high spatial and temporal complexity video encoding are discussed. Such techniques include ranking candidate coding structures based on rate distortion values generated using a first distortion measurement technique, detecting candidate coding structures with large coding unit and transform sizes, and disabling detected candidate coding structures with a distortion, generated using a second distortion measurement technique, that meets or exceeds a threshold.

Abstract: An image decoding method performed by a decoding device according to the present document comprises the steps of: deriving a context model for a sign flag of a current residual coefficient of a current block; and decoding the sign flag on the basis of the context model, wherein the context model for the sign flag is derived on the basis of a sign flag of a residual coefficient decoded before the current residual coefficient in the current block.

Abstract: Methods and devices for a parallel multi-processor encoder system for encoding video data. The video data comprises a sequence of frames, wherein each frame comprises a plurality of blocks of pixels in sequential rows. For each frame, the system divides the plurality of blocks into a plurality of subsets of blocks, wherein each subset of blocks is allocated to a respective processor of the parallel multi-processor system. Each respective processor of the parallel multi-processor system may sequentially encode rows of the subset of blocks allocated to the respective processor and sequentially transmit each encoded row of blocks as a bit stream to a decoder on a channel. For each row, the respective encoded row of blocks is transmitted to the decoder for each processor prior to transmission of the next sequential respective encoded row of blocks for any processor. Additionally, a similar parallel multi-processor decoder system is described.

Abstract: Disclosed is a video signal processing method and device that encodes or decodes a video signal. In particular, the video signal processing method may comprise the steps of: parsing a first syntax element indicating whether a merge mode is applied to a current block; when the merge mode is applied to the current block, determining whether to parse a second syntax element on the basis of a first predefined condition, wherein the second syntax element indicates whether a first mode or a second mode is applied to the current block; when the first mode and the second mode are not applied to the current block, determining whether to parse a third syntax element on the basis of a second predefined condition; and determining a mode applied to the current block on the basis of the second syntax element or the third syntax element.

Abstract: The present disclosure provides methods for performing simplified matrix weighted intra prediction. The method can include: determining a classification of a target block; and generating, based on the classification, a matrix-weighted intra prediction (MIP) signal, wherein determining the classification of the target block comprises: in response to the target block having a size of 4×4, determining that the target block belongs to a first class; or in response to the target block having a size of 8×8, 4×N or N×4, N being an integer between 8 and 64, determining that the target block belongs to a second class.