Tencent America LLC

Qualcomm Incorporated

Tencent Technology (shenzhen) Company Limited

Xiang Li

Shan Liu

Xin Zhao

Xiaozhong Xu

Guichun Li

Liang Zhao

Lien-Fei Chen

Ling Li

Cheung Auyeung

Meng Xu

Byeongdoo Choi

Yixin Du

Stephan Wenger

Marta Karczewicz

Jianle Chen

Kai Zhang

Jing Ye

Li Feng Zhang

Hong Zhang

Madhu Peringassery Krishnan

Hsiao-Chiang Chuang

Vadim Seregin

Wei-Jung Chien

Anish Tamse

Yi-Wen Chen

Krishnakanth Rapaka

Sungwon Lee

Robert Owen Hughes

Thuong Nguyen Canh

Charles J Bieberich

Yeqing Wu

Yu-Chen Sun

Michael Robert Turner

Lienfei Chen

Bin Zhu

Zhongzheng Yuan

Johanna Bakonyi

Ying Chen

Cheng-Teh Hsieh

Tejashree Joglekar

Shuang Liang

Lifen Wu

Robert Sibley

Steven Richard Brunette

Delphine Collin

Hongbin Liu

Feng Zou

Joel Sole Rojals

Chao Pang

Qiang Zhang

Li Zhang

Aspects of the disclosure provide methods and apparatuses for video encoding/decoding. In some examples, an apparatus for video decoding includes receiving circuitry and processing circuitry. The processing circuitry receives coded information of a block that is encoded in a palette based coding mode. The block is a beginning of a predefined coding region that includes one or more coding tree units (CTUs). The processing circuitry further determines a palette for the block independently of palette information of one or more previously decoded blocks of the palette based coding mode, and decodes pixels of the block based on the coded information of the block and the determined palette for the block.

Method and apparatus for video coding

Aspects of the disclosure provide methods and apparatuses for video encoding/decoding. In some examples, an apparatus for video decoding includes receiving circuitry and processing circuitry. The processing circuitry receives a bitstream carrying a plurality of pictures, and determines at least a motion compensation padding (MCP) block that is located in an MCP area outside of a picture and next to a picture boundary of the picture. The processing circuitry derives, according to a plurality of candidates with positions located at the picture boundary within the picture, a motion vector of the MCP block for motion compensated boundary padding, and reconstructs at least a sample in the MCP block according to the derived motion vector for the motion compensated boundary padding.

On motion compensated picture boundary padding

Aspects of the disclosure provide methods and apparatuses for video encoding/decoding. In some examples, an apparatus for video decoding includes processing circuitry. The processing circuitry extracts, from a bitstream, merge with motion vector difference (MMVD) candidate information for a current block in a current picture. The processing circuitry generates a first MV refinement offset associated with a first motion vector for the MMVD candidate based on a refined step size and a plurality of refinement positions. The processing circuitry derives a first refined motion vector (MV) value associated with a MMVD candidate according to the MMVD candidate information and the generated first MV refinement offset. The processing circuitry reconstructing the current block according to a first reference block in a first reference picture, the first reference block is indicated by the derived first refined MV value.

MMVD candidate refinement methods

Aspects of the disclosure provide a method and an apparatus including processing circuitry that adds merge candidates into a merge candidate list of a current block in a current picture. The merge candidates include available merge candidates including one or more of spatial motion vector predictors (MVP(s)), temporal MVP(s), non-adjacent MVP(s), history-based MVP(s), and pairwise average MVP(s). Whether the merge candidate list includes all available SMVP, TMVP, NA-MVP, HMVP, and PAMVP, and no merge candidate in the merge candidate list has a zero motion vector (zero MV) are determined. If the merge candidate list includes all available SMVP, TMVP, NA-MVP, HMVP, and PAMVP, and no merge candidate in the merge candidate list has the zero MV, the merge candidate having the zero MV is added to the merge candidate list. Merge candidates in the merge candidate list including the merge candidate having the zero MV are reordered using template matching.

Zero motion vector in adaptive reordering of merge candidates (ARMC)

Aspects of the disclosure provide methods and apparatuses for video encoding/decoding. In some examples, an apparatus for video decoding includes receiving circuitry and processing circuitry. The processing circuitry determines, a use of an inherited context initialization in a context-based adaptive binary arithmetic coding (CABAC) for decoding a current portion of a video sequence carried by a bitstream. The processing circuitry decodes, from the bitstream, a syntax value that indicates a decoded portion in the video sequence for a context inheriting, and initializes context models for the CABAC based on stored context states associated with the decoded portion. Further, the processing circuitry decodes, the current portion from the bitstream according to the context models that are initialized based on the stored context states associated with the decoded portion.

CABAC inherited context initialization

In a method for video decoding in a decoder, reconstructed samples of a reconstructed block of a picture are stored. When a current sub-block in a current block of the picture is to be reconstructed using intra block copy (IBC) based on a reference sub-block in the reconstructed block, the reference sub-block for the current sub-block is identified, whether the reconstructed samples of the reference sub-block stored are indicated as overwritten is determined based on a position of the current sub-block, reconstructed samples of the current sub-block for output are generated based on the reconstructed samples of the reference sub-block when the reconstructed samples of the reference sub-block stored are determined to be indicated as not overwritten, and the reconstructed samples of a collocated sub-block in the reconstructed block stored are overwritten with the generated reconstructed samples of the current sub-block.

Intra block copy search range

A method of and an apparatus for controlling intra prediction for decoding of a video sequence are provided. The method may include based on a reference line index signaling a first reference line nearest to a coding unit, among a plurality of reference lines adjacent to the coding unit, applying intra smoothing on one or more first reference lines comprising the first reference line, among the plurality of reference lines, and based on the intra smoothing being applied on the one or more first reference lines, applying a position-dependent intra prediction combination (PDPC) on one or more third reference lines comprising the first reference line, among the plurality of reference lines, while preventing application of the PDPC on one or more fourth reference lines other than the one or more third reference lines, among the plurality of reference lines.

Multi-line intra prediction

In a method for video decoding, prediction information of a current block is decoded from a coded video bitstream. The prediction information is indicative of a reference line selected from multiple reference lines and an intra prediction mode selected from a set of potential intra prediction modes that is associated with the reference line. At least one sample of the current block is reconstructed based on the intra prediction mode and at least one reference sample in the reference line. When the reference line is a non-zero reference line, a first set of potential intra prediction modes associated with the non-zero reference line includes a smaller number of potential intra prediction modes compared to a second set of potential intra prediction modes associated with a zero reference line. The first set of potential intra prediction modes only includes most probable modes.

Intra prediction with multiple reference lines

First affine parameters and second affine parameters for each of one or more affine models associated with a current block are determined. The first affine parameters of the respective affine model are associated with a first motion vector for a first reference picture of the current block. The second affine parameters of the respective affine model are associated with a second motion vector for a second reference picture of the current block. The first affine parameters and the second affine parameters of the respective affine model have opposite signs. Control point motion vectors (CPMVs) of the affine motion of the current block are determined by performing the affine bilateral matching based on the determined first affine parameters and the determined second affine parameters of the one or more affine models. The current block is reconstructed based on the CPMVs of the affine motion of the current block.

Affine models use in affine bilateral matching

Aspects of the disclosure provide a method and an apparatus including processing circuitry that performs template matching (TM) on motion vector resolution (MVR) pairs of a current block by determining a TM cost corresponding to each one of the MVR pairs. The current block is predicted with an affine adaptive motion vector prediction (ΔMVP) mode. Each MVR pair includes a first MVR in a first plurality of MVRs corresponding to a first reference picture and a second MVR in a second plurality of MVRs corresponding to a second reference picture. Each TM cost is determined based on a current template of the current block and a bi-predictor of the respective MVR pair. The bi-predictor is based on a first reference template in the first reference picture and a second reference template in the second reference picture. An MVR pair is selected based on the determined corresponding TM costs.

Template-matching based adaptive motion vector resolution (AMVR) for bi-prediction and an affine mode

A method for video decoding includes determining that an angular intra prediction mode for a current block is a wide angle mode. The method further includes determining a non-wide angle mode that corresponds to the wide angle mode, the non-wide angle mode being spaced apart from the vertical mode or the horizontal mode by an angular distance that is less than or equal to the predetermined threshold. The method further includes, in response to a determination that an intra prediction coding tool and coding tool parameters are specified for the determined non-wide angle mode, performing intra prediction for the current block using the wide angle mode, using the intra prediction coding tool, and using the coding tool parameters specified for the determined non-wide angle mode.

Coding tool parameter selection by mapping wide angle intra prediction modes to non-wide intra prediction modes

Aspects of the disclosure provide methods and apparatuses for video encoding/decoding. An apparatus for video decoding includes processing circuitry that decodes prediction information for a current block in a current coded picture. The prediction information indicates a motion vector predictor index (MVP_idx) for selecting a motion vector predictor in a motion vector predictor list. The processing circuitry determines whether the MVP_idx is smaller than a threshold. When the MVP_idx is determined to be smaller than the threshold, the processing circuitry decodes a motion vector difference (MVD) corresponding to the motion vector predictor and reconstructs the current block based on the motion vector predictor and the MVD. When the MVP_idx is determined to be equal to or larger than the threshold, the processing circuitry reconstructs the current block based on the motion vector predictor without the MVD which is not signaled in the coded video sequence.

Methods and apparatuses for video coding

Aspects of the disclosure provide a method and an apparatus including processing circuitry for video decoding. The processing circuitry decodes, from a coded video bitstream, a first syntax element indicating whether a first component in the coded video bitstream is coded based on a second component in the coded video bitstream. The processing circuitry determines whether to decode one or more second syntax elements for a chroma related coding tool based on the first syntax element. The chroma related coding tool is a luma mapping with chroma scaling coding tool or a cross-component adaptive loop filter. The one or more second syntax elements are decoded when the first syntax element indicates that the first component is coded based on the second component. The one or more second syntax elements are not decoded when the first syntax element indicates that the first component is not coded based on the second component.

Signaling presence of chroma component in video bitstream

Video decoding and encoding methods and apparatuses are provided. The decoding method includes: obtaining a first parameter set corresponding to a to-be-decoded video frame; determining an effective quantization matrix (QM) according to syntax elements included in the first parameter set, the effective QM being a QM actually used for inversely quantizing quantized transform coefficients during decoding of the to-be-decoded video frame; and decoding the effective QM.

Video decoding method and apparatus, video encoding method and apparatus, device, and storage medium

Coded information indicates that an adaptive up-sampling filter is applied to a current block in a current picture. A respective class for each of a plurality of subblocks of the current block is determined. A respective filter coefficient set is determined for each of the plurality of subblocks from a plurality of filter coefficient sets of the adaptive up-sampling filter. The respective filter coefficient set is determined based on at least one class corresponding to the respective subblock and a respective sampling rate of reference pixel resampling (RPR) applied on a reference picture of the current picture. The respective sampling rate is associated with one of a plurality of phases of the RPR. The adaptive up-sampling filter is applied to the current block to generate filtered reconstructed samples of the current block based on the determined respective filter coefficient sets without applying a secondary adaptive loop filter (ALF).

Adaptive up-sampling filter for luma and chroma with reference picture resampling (RPR)

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Saratoga, CA, United States of America

Xiang Li