Beijing Dajia Internet Information Technology Co., Ltd.

Tsung-Chuan Ma

Xianglin Wang

Xiaoyu Xiu

Yi-Wen Chen

Bing Yu

Hong-Jheng Jhu

Shuiming Ye

Wei Chen

Che-Wei Kuo

Yun-fei Zheng

A method for video encoding is provided. The method includes obtaining, by an encoder, a plurality of blocks from a video picture, wherein each of the plurality of blocks is to be encoded by an intra prediction mode or an inter prediction mode; in response to a first pre-defined condition being satisfied, determining, by the encoder, that a current block in the plurality of blocks is eligible for an application of Decoder-side Motion Vector Refinement (DMVR); in response to the current block being eligible for both applications of DMVR and Bi-Directional Optical Flow (BDOF), determining, by the encoder, whether a pre-defined criterion based on mode information of the current block is satisfied; avoiding, by the encoder in response to the pre-defined criterion being satisfied, applying BDOF to a subblock in the current block; and outputting, by the encoder by a bitstream, prediction mode information of the current block.

Methods and devices for selectively applying bi-directional optical flow and decoder-side motion vector refinement for video coding

Methods and devices for video encoding are provided. In the method, the device determines, for a current luma transform block in a coding unit, whether an intra subpartition (ISP) split type is an ISP mode. In response to determining that the intra subpartition split type is not the ISP mode, the device determines a first context index for a Coded Block Flag (CBF) flag of the current luma transform block as being equal to zero or one, where the CBF flag specifies whether the current luma transform block comprises one or more transform coefficient levels not equal to zero. In response to determining that the intra subpartition split type is the ISP mode, the device determines the first context index based on whether a current transform unit is a first one to be parsed in the coding unit. The device encodes the CBF flag based on the first context index.

Coding of transform coefficients in video coding

Methods and devices for video coding are provided. In the method, the device determines, for a current luma transform block in a coding unit, whether an intra subpartition (ISP) split type is an ISP mode. In response to determining that the intra subpartition split type is not the ISP mode, the device determines a first context index for a Coded Block Flag (CBF) flag of the current luma transform block as being equal to zero or one, where the CBF flag specifies whether the current luma transform block comprises one or more transform coefficient levels not equal to zero. In response to determining that the intra subpartition split type is the ISP mode, the device determines the first context index based on whether a current transform unit is a first one to be parsed in the coding unit. The device decodes the CBF flag based on the first context index.

Methods and devices for video encoding are provided. In the method, the device divides a current picture into one or more coding units; determines, for a current luma transform block in a current coding unit of the one or more coding units, whether a first variable indicating an intra subpartition (ISP) split type equals ISP_NO_SPLIT. In response to determining the first variable equals ISP_NO_SPLIT, the device determines a luma block flag context index for a luma block flag of the current luma transform block as being equal to zero or one without determining whether the current luma transform block is smaller than the current coding unit. In response to determining the first variable does not equal ISP_NO_SPLIT, the device determines the luma block flag context index based on a second variable of a previous luma transform unit in the current coding unit.

Methods, apparatuses, and non-transitory computer-readable storage mediums are provided for video decoding. The method includes: constructing, by a decoder, a first merge list comprising a plurality of candidates, based on a merge list construction process for regular merge prediction, wherein each one of the plurality of candidates is a motion vector comprising a List 0 motion vector, or a List 1 motion vector, or both; receiving, by the decoder, a first/second index value to indicate a first/second candidate that is chosen from the first merge list; receiving, by the decoder, a first/second binary flag that is coded using a first/second context-adaptive binary arithmetic coding (CABAC) context modeling method to indicate whether a List 0 motion vector of the first/second candidate or a List 1 motion vector of the first/second candidate is selected for a first PU of the geometric prediction.

Methods and apparatuses for video coding with triangle prediction

A method for video encoding is provided. The method may be applied in an encoder and includes: determining, for a first coding block, a quantization parameter and a quantized level; deriving a scale value by scaling the quantization parameter by a scale factor, determining a plurality of parameters associated with a coding unit (CU); obtaining a plurality of bit-shifts by bit-shifting the plurality of parameters; and obtaining a plurality of coefficients associated with the CU based on the quantized level, the scale value, and the plurality of bit-shifts.

Methods and devices for quantization and de-quantization design in video coding

A method for video decoding is provided. The method may be applied in a decoder and includes: receiving a video bitstream comprising a quantization parameter and a quantized level; deriving a scale value by scaling the quantization parameter by a scale factor; determining a plurality of parameters associated with a coding unit (CU); obtaining a plurality of bit-shifts by bit-shifting the plurality of parameters; and obtaining a plurality of coefficients associated with the CU based on the quantized level, the scale value, and the plurality of bit-shifts.

A method for video encoding is provided. The method may be applied in an encoder and includes: determining, for a first coding block, a quantization parameter and a quantized level; deriving a scale value by scaling the quantization parameter by a scale factor; determining a plurality of parameters associated with a coding unit (CU); obtaining a plurality of bit-shifts by bit-shifting the plurality of parameters; and obtaining a plurality of coefficients associated with the CU based on the quantized level, the scale value, and the plurality of bit-shifts.

An electronic apparatus performs a method of updating a most probable modes candidate list for a current block of video data. The electronic apparatus first identifies a neighboring block located at a predefined location relative to the current block and its associated matrix-based intra prediction mode. The electronic apparatus further determines a regular intra prediction mode corresponding to the matrix-based intra prediction mode for the neighboring block according to a predefined mathematical relationship between regular intra prediction modes and matrix-based intra prediction modes. The electronic apparatus additionally inserts the regular intra prediction mode associated with the neighboring block into the most probable modes candidate list according to a predefined order. If the regular intra prediction mode is signaled in the syntax of a video bitstream including the current block, a video decoder will predict the current block from the reconstructed neighboring block according to the regular intra prediction mode.

Methods and apparatus of video coding using improved matrix-based intra prediction coding mode

The present disclosure relates to an intra sub-partition (ISP) method of encoding a video signal. The method includes partitioning a block of video data into a plurality of sub-partitions, obtaining a number of most probable intra predictions based on intra prediction modes of neighboring blocks of a current block and determining an intra prediction mode to predict the samples of the block sub-partitions, selecting an optimal transform combination from DCT-II, DST-VII and DCT-VIII transform kernels for each sub-partition, obtaining residual coefficients of a first sub-partition and deriving dequantized residual coefficients of the first sub-partition, deriving residual samples of the first sub-partition by performing inverse transform on dequantized residual coefficients of the first sub-partition in horizontal and vertical directions, deriving prediction samples of the first sub-partition, and deriving the reconstructed samples of the first sub-partition, and deriving prediction samples of a second sub-partition.

Methods and devices for intra sub-partition coding mode

Methods and apparatuses are provided for video coding. The method includes: partitioning video pictures into a plurality of CUs, at least one CU is further partitioned into two PUs including at least one geometric shaped PU; constructing a first merge list including a plurality of candidates, each candidate being a MV including a List 0 MV, or a List 1 MV; locating a first candidate for the first PU and a second candidate for the second PU according to a first index and a second index, respectively; obtaining a first uni-prediction MV for the first PU by selecting a List X1 MV of the first candidate according to a first binary reference list indication flag; and obtaining a second uni-prediction MV for the second PU by selecting a List X2 MV of the second candidate according to a second binary reference list indication flag.

Methods and apparatuses for video coding using triangle partition

Methods and apparatuses for video coding are provided. The method includes that a decoder determines whether a disable flag is present in a picture header (PH) associated with a picture, wherein the disable flag specifies whether a coding tool is disabled in one or more slices associated with the PH. Additionally, the method includes that the decoder infers value of the disable flag according to one or more enable flags signaled in a sequence parameter set (SPS) of the picture in response to determining that the disable flag is not present in the PH, inferring, by the decoder.

Methods and apparatuses for signaling of syntax elements in video coding

A method of constraining the operations of certain inter-mode coding tools in the derivation of motion vector candidates for inter-mode coded blocks employed in video coding standards, such as the now-current Versatile Video Coding (VVC), is performed at a computing device. The computing device determines whether one or more of the reference pictures associated with an inter-mode coded block involved in an operation of an inter-mode coding tool are long-term reference pictures, and constrains the operation of the inter-mode coding tool on the inter-mode coded block based on the determination.

Constrained motion vector derivation for long-term reference pictures in video coding

Methods, apparatuses, and non-transitory computer-readable storage mediums are provided for decoding a video block in geometry partition mode (GPM). The method may include partitioning the video block into first and second geometric partitions. The method may include obtaining a first motion vector refinement (MVR) for the first geometric partition. The method may include obtaining a second MVR for the second geometric partition. The method may include obtaining a candidate list that comprises a plurality of motion vectors (MVs). The method may include obtaining a first MV from the candidate list for the first geometric partition. The method may include obtaining a second MV from the candidate list for the second geometric partition. The method may include calculating a third MV by adding the first MV with the first MVR for the first geometric partition. The method may include calculating a fourth MV. The method may include obtaining prediction samples.

Geometric partition mode with motion vector refinement

Methods and apparatuses for video coding are provided. The method includes that a decoder determines whether one or more reference picture lists are signaled in a picture header (PH) associated with a picture and whether the one or more reference picture lists indicate that one or more slices associated with the picture are bi-predictive. The method further includes that the decoder adds one or more constraints to one or more syntax elements in the PH in response to determining that the one or more reference picture lists are signaled in the PH and the one or more reference picture lists indicate that the one or more slices are not bi-predictive.

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San Diego, CA, United States of America

Tsung-Chuan Ma