Huawei Technologies Co., Limited

Future Wei Technologies, Inc.

Huawei Technoloiges Co., Ltd.

Roman Igorevich Chernyak

Sergey Yurievich Ikonin

Alexander Alexandrovich Karabutov

Timofey Mikhailovich Solovyev

Jianle Chen

Elena Alexandrovna Alshina

Victor Alexeevich Stepin

Yin Zhao

Haitao Yang

Huanbang Chen

Maxim Borisovitch Sychev

Anand Meher Kotra

Semih Esenlik

Dmitry Yurievich Kuryshev

Han Gao

Biao Wang

Ruslan Faritovich Mullakhmetov

Shan Liu

Jiali Fu

Jiantong Zhou

Shan Gao

Xiang Ma

Igor Igorevich Pasechnik

Albert Yurievich Silantiev

Jose Alvarez

Kamilla Railevna Davletshina

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.

Method and apparatus for intra sub-partitions coding mode

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.

Affine motion model restrictions for memory bandwidth reduction of enhanced interpolation filter

A method of coding is implemented by a decoding device, the method includes: receiving a bitstream, and obtaining from the bitstream, a first luma bit depth value of luma samples of a current picture. The method also includes performing a Hadamard Transform Domain Filtering (HTDF) post reconstruction filtering of a block of the current picture by using a lookup table based on the obtained first luma bit depth value.

Method and apparatus for hadamard transform domain filtering of the video signal with various bit depth

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 Hcontaining motion information of N preceding blocks preceding the block, wherein each history-based motion information candidate comprises: 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.

Method and apparatus for deriving an interpolation filter index for a current block

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 comprising a sequence parameter set (SPS) to obtain the luminance QP and information of a mapping function (ƒ) which associates a QP index (QPi) to a chrominance QP (QPc), wherein the chroma QP mapping table is signaled in the SPS; 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.

Method and apparatus for signaling of mapping function of chroma quantization parameter

A method for inverse quantization of a current block of a picture, the method comprising: receiving a bitstream; obtaining a joint chrominance component residual, JCCR, control flag from the bitstream; obtaining a chrominance mapping information from the bitstream based on the JCCR control flag; obtaining at least one chrominance quantization parameter, QP, offset from the bitstream based on the JCCR control flag; obtaining a QP value for the current chrominance block based on the obtained chrominance mapping information and the at least one obtained chrominance QP offset; performing inverse quantization on the current chrominance block by using the obtained QP value.

Method and apparatus for chrominance quantization parameters signalling

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.

Separate merge list for subblock merge candidates and intra-inter techniques harmonization for video coding

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.

Encoder, a decoder and corresponding methods for inter prediction using geometric prediction mode

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.

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 H, 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.

Video decoder and methods

A method for inverse quantization of a current block of a picture or a frame, where the method is performed by a decoder, and includes obtaining, by a decoder, from a bitstream, a joint chrominance residual (JCCR) mode for a current block of a picture or a frame, obtaining one or more quantization parameter (QP) offset values for chrominance components from the bitstream, determining at least one QP value for the current block depending on the JCCR mode, and performing an inverse quantization process on a chrominance component of the current block using the determined QP value.

Method and apparatus for chrominance QP offsets tables signaling and derivation

A method comprising obtaining a bitstream, the bitstream comprises a transform unit syntax and a coding unit syntax, the transform unit syntax includes a value of a first flag and a value of a second flag related to, respectively, a first chroma transform block and a second chroma transform block of a current transform unit or a current sub-transform unit within the current transform unit, the first or second flag specifies whether the first or second chroma transform block contains at least one transform coefficient levels not equal to 0, the coding unit syntax includes a value of a third flag specifying whether a transform tree structure is present or not; and deriving a value of a fourth flag based on the values of the first, second, and third flags, the fourth flag specifies whether a luma transform block contains at least one transform coefficient levels not equal to 0.

Method and apparatus for signalling flags related to chroma transform blocks

A method related to adaptive usage of pixel-based and block-based affine motion compensation and includes performing sub-block-based affine transform prediction on an affine block with a first sub-block size if the first sub-block size is greater than or equal to a first sub-block size threshold. If the first sub-block size is less than the first sub-block size threshold, it is determined whether a pixel-based motion vector field is not applied for performing motion compensation for the affine block. If the motion vector field is not applied, a sub-block-based affine motion prediction is performed with a second sub-block size that is based on the first sub-block size. If the pixel-based motion vector field is applied, motion compensation is performed for a sub-block of the affine block using the pixel-based motion vector field.

Usage of DCT based interpolation filter and enhanced bilinear interpolation filter in affine motion compensation

Reference picture management scheme is provided in the context of video coding. A method of decoding an encoded video sequence, comprising obtaining a value of a reference picture list (RPL) syntax element from a bitstream of the encoded video sequence, the RPL syntax element specifying whether syntax elements related to reference picture lists are present in the bitstream, when the RPL syntax element specifies that the syntax elements related to the reference picture lists are present in the bitstream, obtaining, from the bitstream, values of the syntax elements related to the reference picture lists; and constructing at least one reference picture list for inter prediction using the obtained values of the syntax elements related to the reference picture lists.

Reference picture management methods for video coding

A method of coding implemented by a decoding/encoding device for coding video data includes for a block coded in affine mode, determining control point motion vectors (CPMVs); determining a reference area in a reference picture corresponding to a sub-block of the affine coded block based on the CPMVs; setting a variable clipMVX equal to TRUE if a size of the reference area is greater than a predefined threshold, otherwise setting a variable clipMVX equal to FALSE; deriving a pixel-based motion vector field for the affine coded block; wherein, if the variable clipMVX is equal to TRUE, the deriving the pixel-based motion vector field further comprises motion vector clipping based on a first clipping range, wherein the first clipping range is determined based on the determined CPMVs and a size of the affine coded block.

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Moscow, Russia

Roman Igorevich Chernyak