Abstract: A method of decoding of a video or picture bitstream implemented by a decoding device, the bitstream including a current sequence parameter set (SPS) comprising syntax elements that apply to a video sequence, the method comprising: obtaining a first syntax element used to determine a maximum number of temporal sublayers that is allowed to be present in each coded layer video sequence) referring to the current SPS, wherein a value of the first syntax element is in a range of 0 to a first value, wherein the first value is a value of a second syntax element used to determine the maximum number of temporal sublayers that is allowed to present in a layer in each coded video sequence referring to a video parameter set, when the second syntax element is referred to by the SPS; decoding the bitstream based on the value of the first syntax element.

Abstract: A method of coding, implemented by a decoding device, includes obtaining a bitstream, wherein at least one bit in the bitstream represents a syntax element for a current block, wherein the syntax element specifies the clipping index of the clipping value for an adaptive loop filter (ALF); parsing the bitstream to obtain a value of the syntax element for the current block, wherein the syntax element is coded using a fixed length code; applying adaptive loop filtering on the current block, based on the value of the syntax element for the current block. Herein fixed length code means that all possible values of the syntax element are signaled using the same number of bits.

Abstract: A partitioning method comprises determining whether a current block of a picture is a boundary block and whether the size of the current block is larger than a minimum allowed quadtree leaf node size; and if the current block is the boundary block and the size of the current block is not larger than the minimum allowed quadtree leaf node size (MinQTSize), applying forced binary tree (BT) partitioning to the current block. A method comprises making a determination that a current block of a picture is a boundary block and that a size of the current block is less than or equal to a minimum allowed quadtree (QT) leaf node size (MinQTSize); and applying, in response to the determination, forced binary tree (BT) partitioning to the current block.

Abstract: The present disclosure provides methods and devices of processing a block according to a merge candidate list, the method comprising: constructing a first list according to motion information of neighboring blocks of a current block; obtaining prediction information of the current block; when the prediction information of the current block indicates that a sub-block prediction is applied to the current block, obtaining a uni-prediction candidate for the current block according to the first list; using, the uni-prediction candidate for the current block to perform inter prediction of the current block. According to embodiment of the present disclosure, the regular merge list can be directly used and there is no need to explicitly generate the uni-prediction merge candidate list for sub-block prediction.

Abstract: A method of coding implemented by a decoding device is provided. The method includes parsing a bitstream to obtain a flag from a picture header of the bitstream, wherein the flag indicates whether a current picture is I picture. when the flag indicates that the current picture is I picture, a syntax element designed for inter prediction is inferred to a default value; or when the flag indicates that the current picture is P or B picture, obtaining a syntax element designed for inter prediction from the picture header.

Abstract: A decoding method and a decoder for decoding a current block of a video frame is provided, wherein the decoding method comprises determining a list of Most Probable Modes (MPMs) for the current block. When at least one condition is satisfied, the list of MPMs includes a DC mode, a Vertical mode, a Horizontal mode, an intra prediction mode corresponding to a value of the Vertical mode with a first offset, and an intra prediction mode corresponding to the value of the Vertical mode with a second offset. The decoding method further includes obtaining a MPM flag and a MPM index for the current block from a bitstream of the video, and obtaining an intra prediction mode for the current block for reconstructing the current block.

Abstract: It is provided a method of prediction coding of a current block, comprising: obtaining an intra prediction mode of a left neighbor block of the current block and an intra prediction mode of an above neighbor block of the current block; constructing a Most Probable Mode (MPM) list of intra prediction modes for the current block, the MPM list comprising at least 5 entries of intra prediction modes as follows: {ang, 2+((ang+61)%64), 2+((ang?1)%64), 2+((ang+60)%64), 2+((ang) %64)} when at least a first condition is fulfilled, where ang represents the intra prediction mode of the left neighbor block or the intra prediction mode of the above neighbor block.

Abstract: Signalling of syntax elements in a sequence parameter set of a video bitstream is addressed. Particularly, it is provided a method of decoding a video bitstream wherein a sequence parameter set, SPS, is coded that contains syntax elements that apply to a video sequence, the method comprising obtaining a value of a first syntax element from the SPS used to specify whether a decoded picture buffer, DPB, parameters syntax structure is present in the SPS and obtaining a value of a second syntax element from the SPS, at least when determining that the value of the first syntax element specifies that the DPB parameters syntax structure is present in the SPS, used to specify the presence of a DPB syntax element in the DPB parameters syntax structure, wherein the DPB syntax element is applied to a temporal sublayer except for the highest temporal sublayer in the video sequence.

Abstract: The present invention relates to the performance of motion vector refinement in a search space for multi-reference inter-prediction. Two or more reference pictures are selected, one of those used for motion vector refinement. Based on an initial estimate of a motion vector to the reference picture for motion vector refinement, a search space in this reference image is constructed. Using template matching, the first motion vector is refined. The second motion vector to another reference picture is calculated using its initial estimate, the initial estimate of the first motion vector and the refined first motion vector.

Abstract: A method of filtering a sample value of a picture and a video decoding apparatus are disclosed, the method comprises: obtaining a reconstructed sample value for a block of the picture; obtaining filter coefficients for adaptive loop filtering according to a bitstream; obtaining a sum value according to the filter coefficients and the reconstructed sample value for the block; rounding the sum value according to a vertical position of a sample in the block, to obtain a rounded sum value; obtaining a filter reconstructed sample value for the block according to the rounded sum value.

Abstract: A method of coding implemented by a decoding device or an encoding device, comprising obtaining indication information for a luma position (cbWidth/2, cbHeight/2) of a current coding block, relative to a top-left luma sample position (xCb, yCb) of the current coding block; setting a value of a luma intra prediction mode associated with the current coding block to a first default value, when the indication information indicates that an Intra Block Copy (IBC) mode or palette mode is applied for the luma component at the luma position (cbWidth/2, cbHeight/2), relative to the top-left luma sample position (xCb, yCb) of the current coding block; and obtaining a value of a chroma intra prediction mode based on the value of the luma intra prediction mode of the current coding block.

Abstract: A method of coding implemented by a decoding device or encoding device, the method comprising obtaining a value of an angle parameter for a current block; obtaining a value of a width of the current block and a value of a height of the current block; calculating a ratio value between the value of the width and the value of height; obtaining a first value according to the value of angle parameter and the ratio value; calculating a sample distance value for a sample in the current block according to the first value; obtaining a prediction value for the sample in the current block according to the sample distance value.

Abstract: Devices and methods for Intra prediction are provided. The method includes: parsing a bitstream, wherein the bitstream includes indication information to indicate whether a closest neighboring reference line to the current block is used for an intra prediction; determining an intra prediction mode of the current block is not Planar mode when the closest neighboring reference line to the current block is not used for the intra prediction; and obtaining an index indicating which intra prediction mode in a set of most probable modes is used for the intra prediction mode of the current block when the intra prediction mode of the current block is not Planar mode. The method can improve the efficiency to determine the intra prediction mode of the current block.

Abstract: A method of video coding a block of a picture includes: obtaining a residual signal resulting from inter- or intra-picture prediction; inferring use of a DCT2 transform core for a sequence of the residual signal; processing the transformation of the block using the inferred transform core.

Abstract: A method of filtering a sample value of a picture includes, when an integer t is less than k and an integer j is in the range of 1 to m, generating, with an integer i in the range of 1 to k-t-1, a first filtered sample value by applying a first filter to the value of the sample p(i,j), where the first filter is supported by a first set of filter support samples, which does not comprise any samples p(i?,j?) with row index i? greater than k-t-1, and generating, with i in the range of k-t to k, a second filtered sample value by applying a second filter to the value of the sample p(i,j), the second filter is supported by a second set of filter support samples, which does not comprise any samples p(i?,j?) with row index i? less than k-t.

Abstract: The present disclosure relates to methods and devices to be employed for encoding and decoding of image or video signal. They include determination of whether or not the size of a current block is larger than a minimum allowed quadtree leaf node size. If the size of the current block is not larger than the minimum allowed quadtree leaf node size, multi-type tree splitting is applied to the current block. The minimum allowed quadtree leaf node size is not larger than a maximum allowed binary tree root node size or the minimum allowed quadtree leaf node size is not larger than a maximum allowed ternary tree root node size.

Abstract: A video processing method, comprising: initializing a HMVP list for a current CTU row when the current CTU is the beginning CTU of a current CTU row; and processing the current CTU row based on the HMVP list. By performing the method, the encoding efficiency and decoding efficiency are improved.

Abstract: A method of filtering a sample value of a picture and a video decoding apparatus are disclosed, the method comprises: obtaining a reconstructed sample value for a block of the picture; obtaining filter coefficients for adaptive loop filtering according to a bitstream; obtaining a sum value according to the filter coefficients and the reconstructed sample value for the block; rounding the sum value according to a vertical position of a sample in the block, to obtain a rounded sum value; obtaining a filter reconstructed sample value for the block according to the rounded sum value.

Abstract: A method of video coding implemented by a coding device includes obtaining block size information of a current block to be coded in an intra sub-partition (ISP) coding mode, determining a partitioning direction based on the block size information, determining, based on the block size information, a number of sub-partitions to which the current block is to be partitioned in the partitioning direction, wherein the sub-partitions are for intra prediction separately with a width of each of the sub-partitions bigger than or equal to 4 or collaboratively by combining at least two of the sub-partitions with a combined width of the at least two sub-partitions bigger than or equal to 4, and coding the sub-partitions.

Abstract: An image processing device for use in an image encoder and/or an image decoder, for deblocking a block edge between a first block and a second block of an image encoded with a block code, is provided. The image processing device comprises a filter for filtering the block edge, configured to, for at least some of the pixels to be filtered, within a deblocking range from the block edge, the deblocking range being perpendicular to the block edge, determine a filtered pixel value from an original pixel value of the pixel and at least one further pixel value, determine a clipping value of the pixel, dependent upon a distance of the pixel from the block edge, and clip the filtered pixel value, using the clipping value resulting in a deblocked pixel value.