Tencent America LLC

Hfi Innovation Inc.

Mediatek Corporation

Tencent Technology (shenzhen) Company Limited

Other

Mediatek Singapore Pte. Ltd.

Xiaozhong Xu

Shan Liu

Xiang Yang Li

Guichun Li

Xiang Li

Jun Tian

Xiang Zhang

Xin Zhao

Chao Huang

Tzu-Der Chuang

Jing Ye

Wei Jiang

Meng Xu

Yu-Chen Sun

Wang-Lin Lai

Wei Wang

Ching-Yeh Chen

Yu-Wen Huang

Wen Gao

Byeongdoo Choi

Ding Ding

Wei W Wang

Stephan Wenger

Thuong Nguyen Canh

Sheng Lin

Lien-Fei Chen

Yiming Li

Jungsun Kim

Zeqiang Li

Liang Zhao

Ding-Yun Chen

Han Huang

Zhenzhong Chen

Roman Chernyak

Yeqing Wu

Weiwei Feng

Yu Wang

Shaw-Min Lei

Jicheng An

Yixin Du

Han Gao

Xianguo Zhang

Yingbin Wang

Chenghao Liu

Liqiang Wang

Chih-Wei Hsu

Anish Tamse

Madhu Peringassery Krishnan

Shih-Ta Hsiang

Ying Hu

Bin Zhu

Biao Wang

Fang-yi Chao

Ling Li

Karen Yun Chang

Jacob Yu

Ethan Schur

A method performed by at least one processor in a decoder includes receiving a coded video bitstream that includes a compressed two dimensional (2D) mesh corresponding to a surface of three dimensional (3D) volumetric object. The method includes predicting a sampled 2D coordinate from at least one previously coded sampled 2D coordinate included in the compressed mesh. The method includes deriving a prediction residual associated with the sampled 2D coordinate. The method further includes reconstructing a 2D coordinate corresponding to a boundary vertex based on the predicted sampled 2D coordinate and the derived prediction residual.

Predictive coding of boundary UV information for mesh compression

A method and apparatus comprising computer code configured to cause a processor or processors to obtain an input mesh corresponding to volumetric data of at least one three-dimensional (3D) visual content, derive a curve of a mesh sequence from the input mesh corresponding to volumetric data, the curve including a plurality of vertices of the input mesh of the mesh sequence, subdivide the derived curve of the mesh sequence by adding subdivided vertices, computing a displacement vector for each of the plurality of subdivided vertices; and entropy code the volumetric data based on the displacement vector from at least one of the subdivided vertices.

Mesh vertex displacements coding

A video bitstream is received. The video bitstream includes a current block comprising a plurality of subblocks and a template region of the current block comprising a plurality of template subblocks adjacent to at least one of a top side and a left side of the current block. A motion vector (MV) located in a center position of the current block is determined. The MV is determined based on at least one MV of the plurality of subblocks of the current block. A MV for each of the plurality of template subblocks is determined based on the MV located in the center position of the current block and a respective MV of a corresponding subblock of the plurality of subblocks that is adjacent to the respective template subblock. The current block is reconstructed based on the determined MVs for the plurality of template subblocks.

Motion vector derivation of subblock-based template-matching for subblock based motion vector predictor

A method and an apparatus including processing circuitry are provided. The processing circuitry determines previous probability information associated with each entropy coded region of multiple regions in a previous picture. The processing circuitry selects, based on (i) a location or a quantization parameter of an independently decodable coding segment in a current picture or (ii) syntax information of the independently decodable coding segment, a region among the multiple regions. Initial probability information for one or more current syntax elements of a block in the independently decodable coding segment is determined based on the previous probability information associated with the selected region. The one or more current syntax elements are first to be entropy decoded in the independently decodable coding segment. The processing circuitry entropy decodes coded bits associated with the one or more current syntax elements into a bin string based on the initial probability information.

Adaptive context-based adaptive binary arithmetic coding (CABAC) initial state selection from coded pictures

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 extracts, from a bitstream, a signal indicative of an application of a template matching based block vector refinement for coding a current block in a current picture referencing (CPR) mode. The processing circuitry derives a first refined block vector associated with the current block according to the template matching based block vector refinement. The first refined block vector includes a first block vector refinement offset applied on a first block vector associated with the current block. The processing circuitry reconstructs the current block according to a first reference block in a same picture as the current block, the first reference block being indicated by the first refined block vector.

Block vector refinement method for intra block copy

The disclosure includes methods and apparatuses that includes processing circuitry that derives a chroma prediction mode of a chroma block in a chroma coding region based on luma coding information of a luma block associated with a position in a reconstructed luma area that is collocated with the chroma block. The chroma coding region is partitioned separately from a collocated luma coding region including the reconstructed luma area. The luma coding information indicates that the luma block is coded with a first coding mode using a first luma BV (an IBC mode or an IntraTMP mode) and a second coding mode. The processing circuitry derives a chroma BV of the chroma block based on a luma BV of the luma block and reconstructs the chroma block based on the chroma prediction mode including the first coding mode and the second coding mode.

Chroma block vector and chroma coding mode derivation

Method, apparatus, and system for texture coordinate prediction for mesh compression are provided. The process may include receiving, for a mesh, a coordinate of a first vertex and a coordinate of a prediction candidate vertex in a three dimensional (3D) space. The process may include determining a stretch perpendicular distance associated with the first vertex and the prediction candidate vertex, the stretch perpendicular distance being based on a conversion of the 3D space into a two dimensional (2D) space, and determining a 2D texture coordinate of the first vertex based on the stretch perpendicular distance associated with the first vertex and the prediction candidate vertex. The process may also include determining a residual of a predicted coordinate of the first vertex and an actual 2D coordinate of the first vertex; and compressing the mesh based on entropy coding the residual.

Texture coordinate prediction in mesh compression

A method and apparatus comprising computer code configured to cause a processor or processors to obtain an input mesh corresponding to volumetric data of at least one three-dimensional (3D) visual content, partitioning the input mesh into a plurality of submeshes, each of the submeshes comprising a respective one of instances of objects, determine a similarity between at least two of the instance of objects, grouping the submeshes based on the determined similarity, and code the volumetric data based on grouping the submeshes.

Methods for instance-based mesh coding

A method of encoding includes receiving a polygon mesh comprising a plurality of original vertices. The method further includes deriving an initial base mesh from the polygon mesh, the initial base mesh including a first set of base mesh vertices. The method further includes performing a symmetrize process on the initial base mesh to generate a symmetrical base mesh that includes a first side having the first set of base mesh vertices and a second side having a second set of base mesh vertices, each base mesh vertex in the first set of base mesh vertices having a corresponding symmetric vertex in the second set of base mesh vertices. The method further includes determining a first displacement between each original vertex in the polygon mesh located on the second side of the symmetrical base mesh and a nearest vertex included in the second set of base mesh vertices.

Base mesh coding by using surface reflection symmetry

A method performed by at least one processor in a decoder includes receiving a coded video bitstream that includes a compressed two dimensional (2D) mesh corresponding to a surface of three dimensional (3D) volumetric object. The method further includes predicting a current vertex included in the compressed 2D mesh based on an interpolation-based hierarchical prediction scheme that uses at least one sampled vertex included in the compressed 2D mesh. The method further includes deriving a prediction residual associated with the predicted current vertex. The method further includes reconstructing a boundary vertex associated with the 3D volumetric object based on the predicted current vertex and the derived prediction residual.

Coding of boundary UV2XYZ index for mesh compression

Aspects of the disclosure provide a method, an apparatus, and non-transitory computer-readable storage medium for video decoding. The apparatus includes processing circuitry configured to decode at least one first key picture of pictures from a multi-view bitstream. The pictures correspond to different views. The at least one first key picture corresponds to at least one first view of the different views. The processing circuitry determines first feature information of content in the at least one first key picture. The processing circuitry decode, based on the multi-view bitstream, a first feature change to the first feature information. The first feature change indicates a content change between a key picture in the at least one first key picture and a first picture. The processing circuitry reconstructs the first picture based on the decoded first feature change, the first feature information, and the key picture in the at least one first key picture.

Feature-based multi-view representation and coding

Aspects of the disclosure include methods and an apparatus for video coding. The apparatus includes processing circuitry that receives coded information of a current block in a current picture. The current block is coded with a first intra prediction mode that is different from a plurality of intra prediction modes including a DC mode, a Planar mode, and angular intra prediction modes. A candidate block in the current picture coded by an intra prediction mode different from the plurality of intra prediction modes is selected. If the candidate block is located within a pre-defined region, a second intra prediction mode is derived from the plurality of intra prediction modes for the candidate block. The second intra prediction mode is associated with the current block and is used to select a transform for the current block and/or to construct a most probable mode (MPM) list for another block.

Intra prediction mode derivation for coding blocks

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

Processing circuitry receives a coded video bitstream comprising coded information of a current block in a current picture, the coded information is indicative of an AMVP-merge mode, the AMVP-merge mode uses a bi-directional predictor including an AMVP predictor in a first direction and a merge predictor in a second direction. The processing circuitry constructs an AMVP candidate list that includes a plurality of AMVP candidates for the AMVP predictor and constructs a merge candidate list that includes a plurality of merge candidates for the merge predictor. The merge candidate list includes an SbTMVP candidate. The processing circuitry determines the AMVP predictor from the AMVP candidate list, determines the merge predictor from the merge candidate list, and reconstructs the current block according to a combination of a first prediction according to the AMVP predictor in the first direction and a second prediction according to the merge predictor in the second direction.

AMVP-merge mode with SBTMVP

Aspects of the disclosure includes methods and apparatuses. One of the apparatuses includes processing circuitry that is configured to receive a bitstream of a current block in a picture. The bitstream includes coding information indicating that the current block is coded according to a prediction mode with a block vector (BV). The processing circuitry determines a reference block in the picture based on the BV of the current block. The reference block and the current block have an overlapped region. The reference block includes both (i) unreconstructed samples in the overlapped region and (ii) reconstructed samples that are outside the overlapped region. The processing circuitry reconstructs the overlapped region in the current block based on the reconstructed samples in the reference block that are outside the overlapped region. In an example, a width of the overlapped region and a height of the overlapped region are multiples of 4.

Intra block copy prediction for overlapped reference block

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State College, PA, United States of America

Xiaozhong Xu