Abstract: Video coding and decoding methods are described. An example method includes performing a conversion between a current video block of a video and a bitstream representation of the current video block by determining a first intra coding mode to be stored which is associated with the current video block using a differential coding mode, where the first intra coding mode associated with the current video block is determined according to a second prediction mode used by the differential coding mode, and where, in the differential coding mode, a difference between a quantized residual of an intra prediction of the current video block and a prediction of the quantized residual is represented in the bitstream representation for the current video block using a differential pulse coding modulation (DPCM) representation.

Abstract: Methods, systems, and devices for performing entropy coding for a palette escape symbol in palette mode coding and decoding are described. An example method for video processing includes performing a conversion between a video having one or more video regions including a current video block and a bitstream representation of the video, wherein the bitstream representation conforms to a format rule that the current video block is coded using a palette mode coding tool, wherein a binarization of an escape symbol for the current video block uses an exponential-Golomb (EG) code of order K, wherein K is a non-negative integer that is unequal to three, and wherein the palette mode coding tool represents the current video block using a palette of representative color values and wherein the escape symbol is used for a sample of the current video block coded without using the representative color values.

Abstract: Methods, systems, and devices for performing entropy coding for a palette escape symbol in palette mode coding and decoding are described. An example method for video processing includes performing a conversion between a video having one or more video regions including a current video block and a bitstream representation of the video, wherein the bitstream representation conforms to a format rule that the current video block is coded using a palette mode coding tool, wherein a binarization of an escape symbol for the current video block uses an exponential-Golomb (EG) code of order K, wherein K is a non-negative integer that is unequal to three, and wherein the palette mode coding tool represents the current video block using a palette of representative color values and wherein the escape symbol is used for a sample of the current video block coded without using the representative color values.

Abstract: History based motion vector prediction is disclosed. In one example method of video processing, initializing, for a conversion between a first region of video and a bitstream of the first region, a first history motion vector predictor (HMVP) table associated with the first region based on at least one of stored multiple HMVP tables, the multiple HMVP tables being used to store motion information associated with regions coded prior the first region; and performing the conversion by using the initialized first HMVP table which includes at least one motion candidate.

Abstract: A method and system of coding video data using affine motion compensation is described. A method may include receiving a current block of video data that is to be decoded using affine motion compensation, and constructing an affine motion vector predictor (MVP) list for one or more control points of the current block of video data, including adding a motion vector from a neighboring block of video data to the affine MVP list in the case that the motion vector has an associated reference picture that is the same as a target reference picture for the current block of video data. A video coder may determine motion vectors for the one or more control points using the affine MVP list, and code the current block of video data with the determined motion vectors for the one or more control points of the current block of video data.

Abstract: Methods, systems, and devices for performing entropy coding for a palette escape symbol in palette mode coding and decoding are described. An example method for video processing includes performing a conversion between a video having one or more video regions including a current video block and a bitstream representation of the video, wherein the bitstream representation conforms to a format rule that the current video block is coded using a palette mode coding tool, wherein a binarization of an escape symbol for the current video block uses an exponential-Golomb (EG) code of order K, wherein K is a non-negative integer that is unequal to three, and wherein the palette mode coding tool represents the current video block using a palette of representative color values and wherein the escape symbol is used for a sample of the current video block coded without using the representative color values.

Abstract: Devices, systems and methods for picture border coding are described. In a representative aspect, a method for processing picture includes segmenting a picture into one or multiple picture segments, determining that a first block of a picture segment covers at least one region that is outside a border of the picture segment, wherein a size of the first block is M×N pixels, selecting a second block of size K×L pixels, where (K?M and L<N) or (K<M and L?N), wherein the second block falls entirely within the picture segment and wherein the second block is used as a largest coding unit, a leaf coding block or a coding tree block; and processing, using a partition tree, the border of the picture segment, wherein the partition tree is based on the size of the second block.

Abstract: A video coder may determine a motion vector of a non-adjacent block of a current picture of the video data. The non-adjacent block is non-adjacent to a current block of the current picture. Furthermore, the video coder determines, based on the motion vector of the non-adjacent block, a motion vector predictor (MVP) for the current block. The video coder may determine a motion vector of the current block. The video coder may also determine a predictive block based on the motion vector of the current block.

Abstract: An example device includes a memory to store the video data, and processing circuitry in communication with the memory. The processing circuitry is configured to compare a value of a dimension of a current block of the stored video data to a value of a corresponding dimension of a neighboring block of the current block to obtain a relative dimension value. The processing circuitry is further configured to determine, based on the relative dimension value, that the current block is to be partitioned according to a prediction tree (PT) portion of a multi-type tree-based partitioning scheme. The PT portion comprises partitioning according to one of a binary tree structure or a center-side triple tree structure. The processing circuitry is further configured to partition, based on the determination, the current block according to the PT portion, to form a plurality of sub-blocks.

Abstract: In a representative aspect, a method for processing pictures includes segmenting a picture into one or multiple picture segments, determining that a first block of a picture segment covers at least one region that is outside a border of the picture segment, wherein a size of the first block is M×N pixels, selecting a second block of size K×L pixels and where (K?M and L<N) or (K<M and L?N) and the second block falls entirely within the picture segment, and processing, using a partition tree, the border of the picture segment, wherein the partition tree is based on the size of the second block, wherein the processing includes splitting the second block into two or three sub-blocks without an indication on the splitting.

Abstract: Devices, systems and methods for adaptive loop filtering are described. In an exemplary aspect, a method for video processing includes performing, for a current video block of a video, a filtering process that uses filter coefficients and comprises two or more operations with at least one intermediate result, applying a clipping operation to the at least one intermediate result, and performing, based on the at least one intermediate result, a conversion between the current video block and a bitstream representation of the video, wherein the at least one intermediate result is based on a weighted sum of the filter coefficients and differences between a current sample of the current video block and neighboring samples of the current sample.

Abstract: A video coder may determine a motion vector of a non-adjacent block of a current picture of the video data. The non-adjacent block is non-adjacent to a current block of the current picture. Furthermore, the video coder determines, based on the motion vector of the non-adjacent block, a motion vector predictor (MVP) for the current block. The video coder may determine a motion vector of the current block. The video coder may also determine a predictive block based on the motion vector of the current block.

Abstract: Devices, systems and methods for adaptive loop filtering are described. In an exemplary aspect, a method for video processing includes performing, for a current video block of a video, a filtering process that uses filter coefficients and comprises two or more operations with at least one intermediate result, applying a clipping operation to the at least one intermediate result, and performing, based on the at least one intermediate result, a conversion between the current video block and a bitstream representation of the video, wherein the at least one intermediate result is based on a weighted sum of the filter coefficients and differences between a current sample of the current video block and neighboring samples of the current sample.

Abstract: Methods, systems, and devices for performing entropy coding for a palette escape symbol in palette mode coding and decoding are described. An example method for video processing includes performing a conversion between a video having one or more video regions including a current video block and a bitstream representation of the video, wherein the bitstream representation conforms to a format rule that the current video block is coded using a palette mode coding tool, wherein a binarization of an escape symbol for the current video block uses an exponential-Golomb (EG) code of order K, wherein K is a non-negative integer that is unequal to three, and wherein the palette mode coding tool represents the current video block using a palette of representative color values and wherein the escape symbol is used for a sample of the current video block coded without using the representative color values.

Abstract: Methods, systems and devices for using flexible and efficient partitioning techniques and in particular, restricting extended quadtree (EQT) partitioning, are described. An exemplary method for visual media decoding includes making a decision, based on one or more conditions, regarding a selective inclusion of one or more signaling bits for a partitioning process in a bitstream representation of a current visual media block of a plurality of visual media blocks, where the partitioning process splits the current visual media block into exactly four sub-blocks including at least one sub-block that has a size different from half of a width of the current visual media block times half of a height of the current visual media block; decoding, based on the bitstream representation, the four sub-blocks; and decoding, based on the four sub-blocks and the partitioning process, the current visual media block.

Abstract: Methods, systems, and devices for using palette mode with different partition structures are described. An example method for video processing includes maintaining, for a conversion between a video comprising one or more video regions comprising a current video block and a bitstream representation of the video, a palette prediction table for a prediction of a palette used in a palette mode coding tool used for the current video block, making a determination that a local dual tree coding is applied to the conversion, modifying, based on the determination, the palette prediction table, and performing, based on the palette prediction table subsequent to the modifying, the conversion, wherein the palette mode coding tool represents the current video block using a palette of representative color values, and wherein the local dual tree coding enables partitioning of chroma blocks independently from corresponding luma blocks based on a block size.

Abstract: Video coding and decoding methods are described. An example method includes determining, based on an applicability rule, that a differential coding mode is applicable to a conversion between a chroma video block of a video and a bitstream representation of the chroma video block, and performing, based on the determining, the conversion between the chroma video block and the bitstream representation of the chroma video block using the differential coding mode, where the chroma video block is represented in the bitstream representation using a difference between a quantized residual of an intra prediction of the chroma video block and a prediction of the quantized residual in the differential coding mode, where the intra prediction is performed in a first direction and the prediction of the quantized residual is performed in a second direction, and where the difference is represented using a differential pulse coding modulation (DPCM) representation.

Abstract: Methods, systems, and devices for performing entropy coding for the palette escape symbol in palette mode coding and decoding are described. An example method for video processing includes performing a conversion between a video comprising one or more video regions comprising a current video block and a bitstream representation of the video, wherein the bitstream representation conforms to a format rule that the current video block is coded using a palette mode coding tool, wherein a binarization of an escape symbol for the current video block uses an exponential-Golomb (EG) code of order K, wherein K is a non-negative integer that is unequal to three, and wherein the palette mode coding tool represents the current video block using a palette of representative color values and wherein the escape symbol is used for a sample of the current video block coded without using the representative color values.

Abstract: An example method includes determining, without receiving explicit signaling, whether motion compensation for a current block of a current picture of video data is to be performed using a four-parameter affine motion model (AMM) defined by two motion vectors (MVs) or using a six-parameter AMM defined by three MVs; deriving values of predictors for MVs of the AMM of the current block; decoding a representation of differences between the values of the MVs of the AMM for the current block and the values of the predictors; determining the values of the MVs of the AMM for the current block from the values of the predictors and the decoded differences; determining, based on the determined values of the MVs of the AMM for the current block of video data, a predictor block of video data; and reconstructing the current block based on the predictor block.

Abstract: Methods, systems and devices for using flexible and efficient partitioning techniques, and in particular, sub-block shapes in extended quadtree partitioning, are described. An exemplary method for visual media decoding includes applying, to a current visual media block, a partitioning process that splits the current visual media block into exactly four sub-blocks including at least one sub-block that has a size different from half of a width of the current visual media block times half of a height of the current visual media block, where a size of the current visual media block is M×N, and the size of the at least one sub-block is based on a minimum value between M and N, or a maximum value between M and N; decoding, based on a bitstream representation, the four sub-blocks; and decoding, based on the four sub-blocks and the partitioning process, the current visual media block.