Abstract: A method of video processing is provided to include: determining a partitioning scheme for partitioning a chroma video region of a video into one or more chroma blocks based on a color format of the video according to a rule; and performing a conversion between the video and a coded representation of the video according to the partitioning scheme.

Abstract: An intra-frame prediction method and device, according to the present invention, enables deriving an intra-frame prediction mode of a current block, determining a pixel line, among a plurality of pixel lines, for the intra-frame prediction of the current block, and carrying out the intra-frame prediction of the current block on the basis of the intra-frame prediction mode and the pixel line. In addition, a first reference pixel of the determined pixel line may be selectively filtered, and a prediction pixel of the current block may be selectively corrected, and thus the accuracy of the intra-frame prediction may be improved.

Abstract: 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.

Abstract: A method of processing visual media 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 using a buffer comprising reference samples from the current picture for derivation of a prediction block of the current video block. The conversion is based according to rule which specifies that, for the bitstream representation to conform the rule, a reference sample in the buffer is to satisfy a bitstream conformance constraint.

Abstract: The present technology makes it easy to present an image having appropriate image quality at a receiver side that receives high-frame-rate moving image data. A video stream obtained by encoding moving image data having a high frame rate is generated. A container containing the video stream is transmitted. Blur control information for controlling blur is inserted into a layer of the container and/or a layer of the video stream. The blur control information gives, for example, weighting coefficients for individual frames in a blurring process for adding image data of neighboring frames to image data of a current frame.

Abstract: Technology for improving coding efficiency by performing a block split suitable for picture coding and decoding is provided.

Abstract: Methods and systems are disclosed for a mobile device to decode video based on available power and/or energy. For example, the mobile device may receive a media description file (MDF) from for a video stream from a video server. The MDF may include complexity information associated with a plurality of video segments. The complexity information may be related to the amount of processing power to be utilized for decoding the segment at the mobile device. The mobile device may determine at least one power metric for the mobile device. The mobile device may determine a first complexity level to be requested for a first video segment based on the complexity information from the MDF and the power metric. The mobile device may dynamically alter the decoding process to save energy based on the detected power/energy level.

Abstract: Devices, systems and methods for sample refinement and filtering method for video coding are described. In an exemplary aspect, a method for video processing includes modifying, for a conversion between a block of a video and a bitstream representation of the video, a refinement value for a prediction sample in the block by applying a clipping operation to refinement value. The refinement value is derived based on a gradient value of an optical flow coding process. An output of the clipping operation is within a range. The method also includes refining the prediction sample based on the refinement value and performing the conversion based on the refined prediction sample.

Abstract: A method of video processing is described. The method includes determining, for a conversion between a current video block of a current picture of a video and a coded representation of the video, an applicability of an alternative interpolation filter, wherein the applicability of the alternative interpolation filter indicates whether to apply the alternative interpolation filter in the conversion; and performing the conversion based on the determining; wherein the applicability of the alternative interpolation filter is determined based on whether a reference picture resampling in which a reference picture of the current picture is resampled to perform the conversion is used.

Abstract: According to embodiments of the present document, a prediction procedure can be performed for image video coding, and the prediction procedure can comprise merge mode motion vector differences (MMVD) and symmetric motion vector differences (SMVD) according inter prediction. The inter prediction can be performed on the basis of reference pictures of a current picture, and types of the reference pictures (e.g. a long-term reference picture, a short-term reference picture, etc.) can be considered for the inter prediction. Accordingly, performance and coding efficiency in the prediction procedure can be increased.

Abstract: An image decoding method includes: deriving a refined L0 motion vector and a refined L1 motion vector by applying decoder-side motion vector refinement (DMVR) based on an L0 motion vector and an L1 motion vector of a current block, deriving prediction samples for the current block based on L0 prediction samples derived based on the refined L0 motion vector and L1 prediction samples derived based on the refined L1 motion vector, and generating reconstructed samples for the current block based on the prediction samples. The L0 prediction samples are derived based on an L0 reference picture and the refined L0 motion vector, and the L1 prediction samples are derived based on an L1 reference picture and the refined L1 motion vector, and deriving the prediction samples comprises determining whether to apply bi-directional optical flow (BDOF) process based on a first POC difference and a second POC difference are the same.

Abstract: An intra-frame prediction method and device, according to the present invention, enables deriving an intra-frame prediction mode of a current block, determining a pixel line, among a plurality of pixel lines, for the intra-frame prediction of the current block, and carrying out the intra-frame prediction of the current block on the basis of the intra-frame prediction mode and the pixel line. In addition, a first reference pixel of the determined pixel line may be selectively filtered, and a prediction pixel of the current block may be selectively corrected, and thus the accuracy of the intra-frame prediction may be improved.

Abstract: A method of video processing includes determining, for a conversion between a current block of a video and a bitstream representation of the video, an operation associated with a list of motion candidates based on a condition related to a characteristic of the current block. The list of motion candidates is constructed for a coding technique or based on information from previously processed blocks of the video. The method also includes performing the conversion based on the determining.

Abstract: Provided is an encoder including circuitry and memory. In operation, the circuitry: derives one or more first motion vectors based on at least one of one or more motion vectors of a first block encoded in an affine mode; derives one or more second motion vectors based on at least one of one or more motion vectors of a second block that has been encoded and is different from the first block; and determines, as motion vector predictors at control points of a current block to be encoded, motion vectors including at least one of the first motion vectors and at least one of the second motion vectors.

Abstract: 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.

Abstract: In one aspect there is disclosed a method of applying deblocking on implicit vertical TU boundaries when the CU width is larger than the maximum TU width and applying deblocking on implicit horizontal TU boundaries when the CU height is larger than the maximum TU height. Some exemplary embodiments include HEVC deblocking and deblocking using longer filters.

Abstract: Devices, systems and methods for sample refinement and filtering method for video coding are described. In an exemplary aspect, a method for video processing includes modifying, for a conversion between a block of a video and a bitstream representation of the video, a refinement value for a prediction sample in the block by applying a clipping operation to refinement value. The refinement value is derived based on a gradient value of an optical flow coding process. An output of the clipping operation is within a range. The method also includes refining the prediction sample based on the refinement value and performing the conversion based on the refined prediction sample.

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: Methods, apparatus and systems for video bitstream generation and parsing are described. One example bitstream decoding method includes parsing a portion of a video bitstream at a video unit level for a first field indicative of whether a slice height is specified for a subpicture partitioning or for a tile partitioning at the video unit level, parsing, due to determining that the first field indicates that the slice height is specified for the subpicture partitioning, N second fields in the portion of the video bitstream to obtain heights for rectangular slices in the video unit, wherein the heights are indicated in multiple of coding tree unit (CTU) heights, and wherein each rectangular slice comprises one or more CTU rows that belong to a same subpicture, wherein N is a positive integer, and decoding, based on the first field and/or the N second fields, the video bitstream to generate a video.

Abstract: An image decoding method according to the present disclosure includes deriving a history-based motion vector prediction (HMVP) buffer for a current block, deriving motion information of the current block based on an HMVP candidate included in the HMVP buffer, generating prediction samples for the current block based on the motion information, and generating reconstructed samples based on the prediction samples, and the HMVP buffer is initialized when processing a first-ordered CTU in a CTU row in which a current CTU is located, and the current block is included in the current CTU.