Abstract: A method for video encoding and decoding using Low-Frequency Non-Separable Transform (LFNST) mode and apparatus thereof are disclosed. The input data correspond to primary transformed data at the encoder and the input data correspond to coded data of the current CU at the decoder. A CU is partitioned into one or more transform blocks (TBs). An LFNST syntax is determined at an encoder side or at a decoder side if one or more conditions are satisfied. The LFNST syntax indicates whether the LFNST mode is applied to the current CU and/or which LFNST kernel is applied when the LFNST mode is applied. The conditions comprise the CBF indications for the target TBs being false. The current CU is encoded or decoded according to the LFNST mode as indicated by the LFNST syntax.

Abstract: Video encoding or decoding methods and apparatuses receive input video data of a luma block and one or more corresponding chroma blocks, compare sizes of the luma and chroma blocks with a maximum transform skip size, and signal or parse a BDPCM luma enabling flag for the luma block when the size of the luma block is smaller than or equal to the maximum transform skip size, and signal or parse a BDPCM chroma enabling flag for the chroma block when the size of the chroma block is smaller than or equal to the maximum transform skip size. The size of the chroma block is derived from the size of the luma block and a color format sampling structure. The luma block is encoded/decoded by BDPCM based on the BDPCM luma enabling flag and the chroma block is encoded/decoded by BDPCM according to the BDPCM chroma enabling flag.

Abstract: A video decoder receives data from a bitstream for a block of pixels to be decoded as a current block of a current picture of a video. The video decoder receives from the bitstream first and second signaled indices for the current block. The video decoder determines first and second merge indices from the first and second signaled indices. The video decoder uses the first and second merge indices to select first and second motion candidates, respectively. The video decoder generates a set of prediction samples in ALWIP mode and performs an inverse secondary transform and an inverse primary transform to generate a set of residual samples of the current block. Enabling or selection of secondary transform and/or primary transform depends on size, width, and/or height for the current block. The video decoder reconstructs the current block by using the set of residual samples and the set of prediction samples.

Abstract: An intra prediction method comprises receiving input data of a current block in a current picture, deriving multiple Most Probable Modes (MPMs) to be included in a MPM list for the current block, setting remaining intra prediction modes as non-MPMs, and encoding or decoding the current block according to a current intra prediction mode selecting from the MPMs and non-MPMs. The first MPM in the MPM list is Planar mode for blocks coded or to be coded in intra prediction, and one or more other MPMs in the MPM list are derived according to a number of available angular mode of one or more neighboring blocks of the current block.

Abstract: A video decoder receives to-be-decoded data from a bitstream for a block of pixels to be decoded as a current block of a current picture of the video. The video decoder generates a first prediction of the current block based on a first prediction mode that is selected from a first candidate list. The video decoder generates a second prediction of the current block based on a second prediction mode that is selected from a second candidate list. The video decoder generates a combined prediction for the current block based on the first prediction and the second prediction. The video decoder reconstructs the current block by using the combined prediction.

Abstract: A video coder receives data from a bitstream for a block of pixels to be encoded or decoded as a current block of a current picture of a video. Upon determining that an applied block setting of the current block satisfies a threshold condition, the video coder generates a first prediction based on a first motion information for a first prediction unit of the current block. The video coder generates a second prediction based on a second motion information for a second prediction unit of the current block. The video coder generates a third prediction based on the first and second motion information for an overlap prediction region that is defined based on a partitioning between the first prediction unit and the second prediction unit. The video coder encodes or decodes the current block by using the first, second, and third predictions.

Abstract: A method and apparatus of prediction for video coding using MH (Multiple Hypothesis) mode are disclosed. According to this method, a block is partitioned into a first partition and a second partition. A first candidate and a second candidate are derived for the first and second partitions respectively. At least one of the first candidate and the second candidate is derived using a candidate list derived for a regular Merge mode (or also called as normal Merge mode). An MH prediction generated by blending a first prediction corresponding to a first candidate and a second prediction corresponding to a second candidate, and the MH prediction is applied to a part of the current block.

Abstract: In a method and apparatus for video coding using Low-Frequency Non-Separable Transform (LFNST) mode, a coding unit (CU) is partitioned into one or more transform blocks (TBs). A syntax is determined at an encoder side or at a decoder side, where the determining step is performed by signaling the syntax at the encoder side or by parsing the syntax at the decoder side if one or more conditions are satisfied. The syntax indicates whether the LFNST mode is applied to the current CU and/or which LFNST kernel is applied when the LFNSF is applied, and the conditions comprise a target condition corresponding to that all target TBs in a target TB set have a TS mode indication as false, and the target TB set is selected from the TBs in the current CU. The current CU is encoded or decoded according to the LFNST mode.

Abstract: A method and apparatus for video coding are disclosed. According to this method, a current block is received at an encoder side or compressed data comprising the current block is received at a decoder side, wherein the current block comprises one luma block and one or more chroma blocks, the current block is generated by partitioning an image area using a single partition tree into one or more partitioned blocks comprising the current block. A target coding mode is determined for the current block. The current block is then encoded or decoded according to the target coding mode, wherein an additional hypothesis of prediction for said one or more chroma blocks is disabled if the target coding mode corresponds to the multi-hypothesis prediction mode and width, height or area of said one or more chroma blocks is smaller than a threshold.

Abstract: Video encoding or decoding methods and apparatuses receive input video data of a luma block and one or more corresponding chroma blocks, compare sizes of the luma and chroma blocks with a maximum transform skip size, and signal or parse a BDPCM luma enabling flag for the luma block when the size of the luma block is smaller than or equal to the maximum transform skip size, and signal or parse a BDPCM chroma enabling flag for the chroma block when the size of the chroma block is smaller than or equal to the maximum transform skip size. The size of the chroma block is derived from the size of the luma block and a color format sampling structure. The luma block is encoded/decoded by BDPCM based on the BDPCM luma enabling flag and the chroma block is encoded/decoded by BDPCM according to the BDPCM chroma enabling flag.

Abstract: The techniques described herein relate to methods, apparatus, and computer readable media configured to decode and/or encode video data. If the current coding block was using more than one hypotheses of prediction data to generate the prediction data, first prediction data is determined for a current coding block of a picture generated using a first prediction mode, and second prediction data is determined for the current coding block generated using a second prediction mode. Information derived from at least one of the first prediction mode and the second prediction mode can be stored. The stored information can be referenced by the subsequent coding blocks.

Abstract: A video processing method for a video encoder or decoder comprises receiving input data of a current chroma block in a current picture coded in a 4:2:2 color format, determining a luma mode of a luma block corresponding to the current chroma block, mapping the luma mode to a mapped intra mode of the current chroma block, selectively replacing the mapped intra mode by wide angle intra prediction mapping based on a width to height ratio of the current chroma block, deriving an intra predictor according to the mapped intra mode after wide angle intra prediction mapping, and encoding or decoding the current chroma block according to the intra predictor. The mapped intra mode is mode 57 when the luma mode is mode 61 and the mapped intra mode is mode 55 when the luma mode is mode 57.

Abstract: A video coder implementing affine prediction is provided. The video coder receives input data associated with a current block to be coded. The video coder derives a control point motion vector (CPMV) of the current block according to an affine model. The video coder derives a set of motion compensation motion vectors (MCMVs) for a set of sub-blocks of the current block based on the derived CPMV of the current block according to the affine model. The video coder performs motion compensation for the current block based on the set of MCMVs. The CPMV of the current block is derived based on a CPMV of a first reference block that is a neighboring block located in a same region of the current block or an MCMV of a second reference block that is not a neighboring block located in the same region of the current block.

Abstract: A video processing method for a video encoder or decoder comprises receiving input data of a current chroma block in a current picture coded in a 4:2:2 color format, determining a luma mode of a luma block corresponding to the current chroma block, mapping the luma mode to a mapped intra mode of the current chroma block, selectively replacing the mapped intra mode by wide angle intra prediction mapping based on a width to height ratio of the current chroma block, deriving an intra predictor according to the mapped intra mode after wide angle intra prediction mapping, and encoding or decoding the current chroma block according to the intra predictor. The mapped intra mode is mode 57 when the luma mode is mode 61 and the mapped intra mode is mode 55 when the luma mode is mode 57.

Abstract: A method and apparatus of prediction for video coding are disclosed. According to the method, when the Intra Sub-Partition (ISP) mode is applied to a block, the block is partitioned into multiple sub-blocks horizontally or vertically. A target horizontal transform and a target vertical transform are determined from a candidate transform set for each of the multiple sub-blocks according to a target setting belonging to a setting group comprising unified setting and block setting. The target horizontal transform and the target vertical transform selected are then applied to each of the multiple sub-blocks. According to another method, a target horizontal and vertical transform are determined from a candidate transform set without a transform index for the current block according to unified setting, wherein the unified setting comprises two or more Intra modes or Intra-related modes.

Abstract: Method and apparatus of video coding are disclosed. According to one method, in the decoder side, a predefined Intra mode is assigned to a neighboring block adjacent to the current luma block when the neighboring block satisfies one or more conditions. An MPM (Most Probable Mode) list is derived based on information comprising at least one of neighboring Intra modes. A current Intra mode is derived utilizing the MPM list. The current luma block is decoded according to the current Intra mode According to another method, a predefined Intra mode is assigned to a neighboring block adjacent to the current luma block if the neighboring block is coded in BDPCM (Block-based Delta Pulse Code Modulation) mode, where the predefined Intra mode is set to horizontal mode or vertical mode depending on prediction direction used by the BDPCM mode.

Abstract: Video processing methods and apparatuses implemented in a video encoding or decoding system with conditional secondary transform signaling. The video encoding system determines and applies a transform operation to residuals of one or more transform blocks to generate final transform coefficients, and skip signaling a secondary transform index if a position of a last significant coefficient in each considered transform block is less than or equal to a predefined position; otherwise, the video encoding system signals a secondary transform index according to the transform operation.

Abstract: A method and apparatus of prediction for video coding are disclosed. According to one method, a luma Intra prediction mode is determined for a corresponding luma block collocated with the current chroma block, where a predefined mode is assigned to the luma Intra prediction mode when the corresponding luma block collocated with the current chroma block satisfies one or more conditions. A chroma Intra prediction mode is determined for the current chroma block according to the luma Intra prediction mode. The current chroma block is then encoded or decoded according to the chroma Intra prediction mode. According to another method, a predefined mode is assigned to Intra prediction mode for the current block when the current block satisfies one or more conditions. The current block is then encoded or decoded according to the Intra prediction mode.

Abstract: Video processing methods and apparatuses in a video encoding or decoding system for transforming residuals of transform blocks into final transform coefficients or inverse transforming final transform coefficients into residuals. In order to solve the latency issue, exemplary embodiments check if a width or height of a coding block is larger than a predefined threshold, and disable secondary transform or inverse secondary transform for any transform block within the coding block if the width or height of the coding block is larger than the predefined threshold. Another embodiment checks if there are multiple transform blocks in a coding block, and disables secondary transform or inverse secondary transform if the coding block contains multiple transform blocks.

Abstract: Video processing methods and apparatuses implemented in a video encoding or decoding system with conditional secondary transform signaling. The video encoding system determines and applies a transform operation to residuals of a transform block to generate final transform coefficients, and adaptively signals a secondary transform index according to a position of a last significant coefficient in the transform block. A value of the secondary transform index is determined according to the transform operation.