Abstract: The present disclosure relates to motion vector refinement. As a first step, an initial motion vector and a template for the block are obtained. Then, the refinement of the initial motion vector is determined by template matching with said template in a search space. The search space is located on a position given by the initial motion vector and includes one or more fractional sample positions, wherein each of the fractional sample positions belonging to the search space is obtained by interpolation filtering with a filter of a predefined tap-size assessing integer samples only within a window, said window being formed by integer samples accessible for the template matching in said search space.

Abstract: A method of coding implemented by a decoding device, comprising obtaining a bitstream; obtaining a value of an indicator for a current block according to the bitstream; obtaining a value of a first parameter for the current block and a value of a second parameter for the current block, according to the value of the indicator and a predefined lookup table; obtaining a value of a sample distance for a sample which is located in the current block, according to the value of the first parameter and the value of the second parameter; obtaining a prediction value for the sample, according to the value of the sample distance for the sample.

Abstract: A method of coding implemented is provided. The method includes the following operations: obtained the height and width of a prediction block without applying clipping operation; calculating a value of a vertical component of an intra prediction sample based on the height and width of the prediction block; calculating a value of a horizontal component of the intra prediction sample based on the height and width of the prediction block; and generating the intra prediction sample based on the value of the vertical component and the value of the horizon component.

Abstract: A method of coding implemented by a decoding device, comprising obtaining a video bitstream; decoding the video bitstream to obtain an initial intra prediction mode value for chroma component of a current coding block; determining whether a ratio between a width for luma component of the current coding block and a width for chroma component of the current coding block is equal to a threshold or not; obtaining a mapped intra prediction mode value for chroma component of the current coding block according to a predefined mapping relationship and the initial intra prediction mode value, when it's determined that the ratio is equal to the threshold; obtaining a prediction sample value for chroma component of the current coding block according to the mapped intra prediction mode value.

Abstract: The present disclosure provides a coding method, wherein the coding includes decoding or encoding, and the method comprises determining whether a current coding unit is predicted by application of combined inter-intra prediction (CHIP); and in response to determining that the current coding unit is predicted by application of CIIP, setting a boundary strength of a boundary of the current coding unit to a first value.

Abstract: The present disclosure provides apparatuses and methods for splitting an image into coding units. An image is divided into coding tree units (CTUs) which are hierarchically partitioned. Hierarchical partitioning includes multi-type partitioning such as binary tree or quad tree splitting. For CTUs completely within the image and CTUs on the boundary, respective multi-type partition depths are chosen. The present disclosure provides for multi-type partitioning flexibility in a boundary portion of the image.

Abstract: The present disclosure provides methods and devices. A video method of coding implemented by a decoding device, comprising: when a prediction mode of a current coding block is intra prediction, and the current coding block is processed by using Intra sub-partition coding mode, determining whether a width of a current transform block is larger than or equal to a first threshold or not, and whether the width of the current transform block is smaller than or equal to a second threshold or not, the current transform block corresponding to the current coding block; when the width of the current transform block is larger than or equal to the first threshold and the width of the current transform block is smaller than or equal to the second threshold, performing transform process on the current transform block, wherein a transform core based on DST 7 is used on horizontal direction transform.

Abstract: A method for coding implemented by a decoding device or an encoding device includes: obtaining a first prediction mode for a first sub-block, obtaining a second prediction mode for a second sub-block; obtaining a first prediction value for a sample in the current block according to the first prediction mode, obtaining a second prediction value for the sample in the current block according to the second prediction mode; obtaining a value of an indicator, the value of the indicator indicating a blending operation which is performed for the sample in the current block; and obtaining a combined prediction value for the sample in the current block, according to the value of the indictor, the first prediction value, and the second prediction value. The blending operation adaptively performs around a separation line dividing the current block into at least the first sub-block and the second sub-block.

Abstract: The present disclosure relates generally to video coding and picture partitioning methods. In particular, the disclosure is concerned with relations between partition constraint elements, by setting partitioning rules for different picture partitioning methods. The disclosure provides devices and corresponding methods for generating or processing a bitstream including encoded pictures, particularly for setting and including partition constraint element into the bitstream. One of the devices is configured to determine a minimum luma size of a leaf block resulting from quadtree splitting (MinQtSizeY), determine a maximum luma size of a coding block where partitioning using a binary tree splitting is allowed (MaxBtSizeY) based on the MinQtSizeY, and include information for the determined MinQtSizeY into the bitstream.

Abstract: The present disclosure provides an encoding apparatus and a decoding apparatus, as well as an encoding method and a decoding method. In particular, the present disclosure relates to block partitioning and signaling the partitioning parameters in a bitstream. An override flag in a slice header indicates whether or not a block is to be partitioned according to a first partition constraint information. The override flag is included in the bitstream and the block is partitioned accordingly.

Abstract: A deblocking filter of an image processing device is provided. The deblocking filter is used in an image coding process, for deblocking a block edge between a first coding block and a second coding block of an image. The first block has SA samples perpendicular to the block edge by N samples parallel to the block edge, and the second block has SB samples perpendicular to the block edge by N samples parallel to the block edge. No more than IA samples of the first coding block are used as first filter input values, and no more than IB samples of the second coding block are used as second filter input values. No more than MA samples of the first coding block are modified as first filter output values, and no more than MB samples of the second coding block are modified as second filter output values.

Abstract: A method operates a two-dimensional (2D) separable interpolation filter for coding a video. The 2D separable interpolation filter includes a first second one-dimensional (1D) interpolation filter and a temporal buffer. The method includes: obtaining filter coefficients for the first 1D interpolation filter; comparing a sum of positive filter coefficients of the obtained filter coefficients with a threshold; and upon determining that the sum of positive filter coefficients is larger than the threshold, amending one or more of the filter coefficients to obtain amended filter coefficients, the filter coefficients being amended such that a sum of positive filter coefficients is not larger than the threshold; applying the amended filter coefficients to samples of the video to obtain a value of a fractional sample position of the video; re-scaling the value of the fractional sample position; and storing the re-scaled value of the fractional sample position in the temporal buffer.

Abstract: Embodiments of the present disclosure relate to the field of picture processing. Especially, the embodiments are directed to improving the deblocking filter of an image coding device. During the deblocking, at most a number MA of sample values of the first coding block adjacent to the block edge are modified and at most a number MB of sample values of the second coding block adjacent to the block edge are modified; or at most a number MA of sample values of the second coding block adjacent to the block edge are modified and at most a number MB of sample values of the first coding block adjacent to the block edge are modified, MA?MB.

Abstract: Apparatuses and methods for encoding and decoding a video are provided. The method includes determining whether at least one of two blocks of an image in a video is predicted with a combined inter-intra prediction (CIIP), where the two blocks include a first block (block Q) and a second block (block P). There is a boundary between the two blocks. The method further includes setting a boundary strength (Bs) for the boundary to a first value when at least one of the two blocks is predicted with the CHIP, and performing deblocking filter based on the Bs.

Abstract: The present disclosure provides methods and devices of construct a candidate merge list for Intra block copy (IBC) mode, the method comprising: inserting a block vector of a left neighboring block of a current block into an initial merge list, when the left neighboring block is available and the left neighboring block is using IBC mode; inserting a block vector of an above neighboring block of the current block into the initial merge list, when the above neighboring block is available, the above neighboring block is using IBC mode and the block vector of the above neighboring block is not same as the block vector of the left neighboring block; inserting a block vector of the last candidate in a history based motion vector predictor (HMVP) into the initial merge list; obtaining a block vector of the current block according to the initial merge list.

Abstract: Embodiments of the present disclosure relate to the field of picture processing. Especially, the embodiments are directed to improving the deblocking filter of an image coding device. During the deblocking, at most a number MA of sample values of the first coding block adjacent to the block edge are modified and at most a number MB of sample values of the second coding block adjacent to the block edge are modified; or at most a number MA of sample values of the second coding block adjacent to the block edge are modified and at most a number MB of sample values of the first coding block adjacent to the block edge are modified, MA?MB.

Abstract: A method for coding implemented by a decoding device or an encoding device includes: obtaining a first prediction mode for a first sub-block, obtaining a second prediction mode for a second sub-block; obtaining a first prediction value for a sample in the current block according to the first prediction mode, obtaining a second prediction value for the sample in the current block according to the second prediction mode; obtaining a value of an indicator, the value of the indicator indicating a blending operation which is performed for the sample in the current block; and obtaining a combined prediction value for the sample in the current block, according to the value of the indictor, the first prediction value, and the second prediction value. The blending operation adaptively performs around a separation line dividing the current block into at least the first sub-block and the second sub-block.

Abstract: A system and method for processing a video stream are provided. When coding or decoding a video stream a de-blocking filtering may be applied for reducing discontinuities caused by use of a block-based video coding. The de-blocking filtering is performed using a filter grid. The size of the filter grid is chosen adaptively based on the processing parameters. The adaptive size of the filtering grid is determined based on the number of samples used and modified in de-blocking filtering of an edge of a coding block. The filtering grid may be used both for vertical and horizontal edge filtering.

Abstract: The general intra prediction process is unnecessarily complicated with inclusion of the reference sample filtering. This application provides solutions for this problem. A method for intra prediction is provided. The method includes: during an intra predicted sample generation stage, obtaining a filtering indication, which indicates whether a filtered value or an unfiltered value of reference samples of the current coding block will be used. When the value of the filtering indication is true, a prediction sample is generated by using the filtered value of the reference samples based on the planar mode. When the value of the filtering indication is false, a prediction sample is generated by using the unfiltered value of the reference samples based on the planar mode. As a result, the reference sample filtering stage can be fully removed or can be combined with other stage.

Abstract: The present disclosure provides a method of coding implemented by a decoding device, the method comprising: obtaining a value of a splitting mode index for a current coding block; obtaining a value of an angle index for the current coding block according to the value of the splitting mode index value and a pre-stored table; setting a value of an index partIdx according to the value of the angle index; and storing motion information for the current coding block according to the value of the index partIdx.