Abstract: A method for coding a video implemented in an encoder or a decoder, comprising: determining control point motion vectors, CPMVs, for a block according to affine inter-prediction, according to a preselected affine motion model, the block being an affine block; performing motion compensation for the block using a pixel-based motion vector field according to values of the CPMVs, upon fulfilling at least one of the following conditions: A) for a predefined size of a sub-block of M×M, during processing of one line, respectively, of the sub-block the number of lines of the reference picture is less than N, where N is an integer and N is larger than 2.

Abstract: A method for coding a video implemented in an encoder or a decoder including the enhanced interpolation filter, EIF, for motion compensation, the method comprising: i) determining control point motion vectors, CPMVs, for a block according to affine inter-prediction, the block being an affine block or a sub-block of the affine block; ii) for a predefined sub-block size determining a reference area for a sub-block with the predefined sub-block size according to values of the CPMVs; iii) comparing the determined reference area with a predefined threshold; iv) applying EIF for motion compensation, comprising deriving the pixel-based motion vector field for the block; wherein if the determined reference area is larger than the threshold, deriving the pixel-based motion vector field for the block further comprises motion vector clipping, wherein motion vector clipping range is determined based on motion model of the block and the size of the block.

Abstract: A method for deriving motion information for a current block includes: determining whether the current block and a top neighboring block of the current block are in a same coding tree unit (CTU) or not; obtaining a position of a spatial motion information candidate for the current block; obtaining motion information corresponding to the position of the spatial motion information candidate, depending on the result of whether the current block and top neighboring block of the current block are in the same CTU; adding the obtained motion information to a motion information candidate list for the current block; obtaining a value of a first index of a motion information candidate; and deriving motion information of the current block based on the motion information candidate list and the value of the first index.

Abstract: A method for deblocking a chroma block edge between a first chroma block of a first image block and a second chroma block of a second image block. The method includes a decision process which includes: determining a first chroma quantization parameter for the first chroma block based on a first luma quantization parameter of a first luma block of the first image block and a chroma QP mapping table for the first chroma block; determining a second chroma quantization parameter for the second chroma block based on a second luma quantization parameter of a second luma block of the second image block and a chroma QP mapping table for the second chroma block; determining an averaged and rounded chroma quantization parameter based on the first chroma quantization parameter and the second chroma quantization parameter; and determining a threshold parameter based on the averaged and rounded chroma quantization parameter.

Abstract: A method of obtaining quantization parameter (QP) for chrominance components based on QP for luminance component, wherein the method is performed by a decoder or encoder, and wherein the method comprises obtaining a luminance QP for a luma component of a coding unit; obtaining a QP index (QPi) based at least in a part on the luminance QP; and obtaining a chrominance QP (QPc) for a chroma component of the coding unit based on the QP index by using a preset lookup table, wherein the maximum difference between the QP index and the chrominance QP is equal to 3.

Abstract: A method of obtaining a chrominance quantization parameter (QP) for chrominance components based on a luminance QP for luminance component, wherein the method is performed by a decoder, comprising parsing a received bitstream to obtain the luminance QP and information of a mapping function (ƒ) which associates a QP index (QPi) to the chrominance QP (QPc); obtaining the QPi based at least in a part on the luminance QP; obtaining the mapping function based on the obtained information; and obtaining a QPc based on the obtained mapping function and the obtained QPi.

Abstract: A method of obtaining a chrominance quantization parameter (QP) for chrominance components based on a luminance QP for a luminance component, wherein the method is performed by a decoder, and comprises parsing a received bitstream to obtain the luminance QP and information of a mapping function (ƒ) which associates a QP index (QPi) to a chrominance QP (QPc); obtaining the QPi based at least in part on the luminance QP; obtaining the mapping function based on the obtained information of the mapping function; and obtaining a QPc based on the obtained mapping function and the obtained QPi.

Abstract: The disclosure relates to an in-loop filter apparatus for video coding, which is configured for processing a reconstructed frame corresponding to a current frame for generation of a filtered reconstructed frame, wherein the reconstructed frame comprises a plurality of pixels, each pixel being associated with a pixel value.

Abstract: The present disclosure relates to video encoding and decoding, and in particular, a method for inter prediction for a block in a frame of a video signal includes: constructing a history-based motion information candidate list, wherein the list is an ordered list comprising N history-based motion information candidates Hk containing motion information of N preceding blocks preceding the block, wherein each history-based motion information candidate comprises elements: one or more motion vectors (MVs), one or more reference picture indices corresponding to the MVs, and an interpolation filter index; adding one or more history-based motion information candidates from the history-based motion information candidate list into a motion information candidate list for the block; and deriving motion information for the block based on the motion information candidate list.

Abstract: A video coding apparatus is described for encoding or decoding a frame of a video, the video coding apparatus comprising a computer program code and a processor configured to carry out operations on the frame of video. The operations include reconstructing the frame, and determining one or more filter parameters and filtering in a frequency domain and a pixel domain a block of the reconstructed frame based on the determined filter parameters to obtain a filtered block of the frame. The determining the one or more filter parameters and filtering in a frequency domain based on the determined filter parameters is performed jointly within a loop, and the one or more filter parameters are based on one or more first parameters that are based on the reconstructed frame and one or more second parameters which are based on a codec signaling information.

Abstract: The disclosure relates to an in-loop filter apparatus for video coding, which is configured for processing a reconstructed frame corresponding to a current frame for generation of a filtered reconstructed frame, wherein the reconstructed frame comprises a plurality of pixels, each pixel being associated with a pixel value.

Abstract: Apparatuses and methods for Intra Sub-Partitions (ISP) are provided. The method includes: obtaining information of ISP, and determining a size of a chroma transform block (TB) of the coding unit based on SubWidthC and SubHeightC when at least a first condition is fulfilled. The first condition includes the information of ISP indicates that ISP is used for splitting the luma coding block. SubWidthC and SubHeightC are variables depending on chroma format information. The chroma format information indicates a chroma format of a picture the coding unit belongs to. The method can apply to all chroma format. The chroma format includes at least one of: 4:2:0, or 4:2:2, or 4:4:4. An accurate and versatile way to determine the size of the chroma transform block for the ISP is achieved.

Abstract: A method of coding implemented by a decoding device or encoding device, the method comprising obtaining a bitstream, the bitstream comprises a transform unit syntax; the syntax comprises at least two cbf flags for chroma blocks (in an example, transform unit syntax correspond to either transform unit or sub-transform units which include two chroma cbf flags: tu_cbf_cb and tu_cbf_cb—one flag for each chroma plane), a chroma cbf flag specifies whether certain block has residue in correspondent color plane; deriving a value of a luma cbf flag tu_cbf_luma based on one or any combination of a value of a cu_cbf flag, values of two chroma cbf flags corresponding to a current transform unit or sub-transform unit, location of the sub-transform unit within transform unit, values of luma and chroma cbf flags correspondent to previous sub-transform units in the current transform unit.

Abstract: A method of determining a distance table of a merge with motion vector difference (MMVD) mode, wherein the method comprises determining a reference picture from at least one reference picture list of a current processing unit based on at least one parameter of the reference picture, and obtaining the distance table for the current processing unit based on the reference picture, wherein the at least one parameter of the reference picture comprises a picture order count (POC) number of the reference picture, a number of MMVD blocks of the reference picture, a reference picture list index of the reference picture, a reference picture index of the reference picture, and a quantization parameter (QP) of the reference picture.

Abstract: The present disclosure relates to the search of more than one K-integer best-matching blocks per block within an image, corresponding to best patches for subsequent filtering. In particular, the positions of K best-matching blocks for a template block are found within an image search area, by performing calculations of the similarity between the template block and a test block at all offset positions within a search area. The positions of K or more best-matching blocks for a non-template block are found within an image search area, by performing calculations of the similarity between the non-template block and a test block at all offset positions found as offsets of best-matching blocks for all template blocks.

Abstract: A method for inverse quantization of a current block of a picture is performed by a decoder, and the picture comprises a luminance component and a chrominance component, wherein the luminance component and the chrominance component are partitioned into multiple blocks. The method includes: obtaining one or more existing quantization parameter (QP) values from a received bitstream, wherein the one or more existing QP values relate to a current block in the chrominance component; determining a QP value for the current block in the chrominance component based on the one or more existing QP values; and performing inverse quantization on the current block in the chrominance component by using the determined QP value.

Abstract: A prediction method for an image block comprising a first prediction sub-block and a second prediction sub-block, the prediction method comprising: parsing a first index from a bitstream, wherein the first index is used to obtain prediction information of the first prediction sub-block; parsing a second index from the bitstream; comparing the first index with the second index; adjusting the second index in the event that the second index is equal to or greater than the first index; and obtaining prediction information of the second prediction sub-block according to the adjusted second index.

Abstract: A method for deblocking a chroma block edge between a first chroma block of a first image block and a second chroma block of a second image block. The method includes a decision process which includes: determining a first chroma quantization parameter for the first chroma block based on a first luma quantization parameter of a first luma block of the first image block and a chroma QP mapping table for the first chroma block; determining a second chroma quantization parameter for the second chroma block based on a second luma quantization parameter of a second luma block of the second image block and a chroma QP mapping table for the second chroma block; determining an averaged and rounded chroma quantization parameter based on the first chroma quantization parameter and the second chroma quantization parameter; and determining a threshold parameter based on the averaged and rounded chroma quantization parameter.

Abstract: The present disclosure relates to methods and apparatuses for encoding video data into a bitstream and for decoding video data received in a bitstream. A second control flag indicating whether or not to use multi-hypothesis prediction for intra and inter mode is generated and transmitted only conditionally, upon a determination whether or not separate merge list technique for subblock merge candidates is used. On the other hand, a decoder is capable of deciding usage of multi-hypothesis prediction for intra and inter mode and separate merge list technique for subblock merge candidates even though the second control flag is transmitted only conditionally.

Abstract: The present disclosure relates to video encoding and decoding, and in particular to determining motion information for a current block using a history-based motion vector predictor, HMVP, list. The HMVP list is constructed, with said list being an ordered list of N HMVP candidates Hk, k=0, . . . , N?1, which are associated with motion information of N preceding blocks of the frame and precede the current block. Each HMVP candidate has motion information including elements of one or more motion vectors, MVs, one or more reference picture indices corresponding to the MVs, and one or more bi-prediction weight indices. One or more HMVP candidates from the HMVP list are added into a motion information candidate list for the current block; and the motion information is derived based on the motion information candidate list.