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

Chao Huang

Xin Zhao

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

Sheng Lin

Yiming Li

Jungsun Kim

Zeqiang Li

Thuong Nguyen Canh

Liang Zhao

Ding-Yun Chen

Han Huang

Zhenzhong Chen

Yeqing Wu

Lien-Fei Chen

Weiwei Feng

Roman Chernyak

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

Ling Li

Fang-yi Chao

Ethan Schur

Karen Yun Chang

Jacob Yu

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

In some examples, an apparatus for mesh coding includes processing circuitry. The processing circuitry receives a data structure for a mesh frame with polygons representing a surface of an object. The data structure for the mesh frame includes a UV atlas that associates vertices of the mesh frame to UV coordinates in the UV atlas. The processing circuitry determines respective sampling rates for regions of the mesh frame according to respective characteristics of the regions of the mesh frame and applies, on the UV atlas, the respective sampling rates for the regions of the mesh frame to determine sampling positions on the UV atlas. The processing circuitry generates one or more sampled two dimensional (2D) maps for the mesh frame according to the sampling positions on the UV atlas, and encodes the one or more sampled 2D maps into a bitstream.

Method and apparatus of adaptive sampling for mesh compression by encoders

Aspects of the disclosure include methods and apparatuses for video coding. The apparatuses include processing circuitry that receives a bitstream including a first sub-bitstream that corresponds to a scaled version of a current picture and a second sub-bitstream that corresponds to a current picture in a full scale. The processing circuitry reconstructs the scaled version of the current picture from the first sub-bitstream and reconstructs a second block in the current picture in the full scale based on (i) partitioning information of one or more first blocks in the scaled version of the current picture or (ii) intra prediction information of the one or more first blocks.

Scaled intra reference picture

Aspects of the disclosure includes methods and apparatuses for mesh processing and a method of processing mesh data. The apparatus for mesh processing includes processing circuitry configured to receive coded information indicating that a displacement field of a chroma component of a current frame is down-sampled according to a sampling format. The down-sampled displacement field of the chroma component includes a first array of displacement vectors. The processing circuitry is configured to reconstruct the first array of displacement vectors of the down-sampled displacement field and up-sample the down-sampled displacement field according to the sampling format to generate an up-sampled displacement field of the chroma component that includes a second array of displacement vectors. The second array of displacement vectors includes the first array of displacement vectors and additional displacement vectors.

Upsampling of displacement field in mesh compression

An apparatus for video decoding includes processing circuitry. The processing circuitry decodes prediction information for a chroma block. The prediction information indicates (i) an intra block copy mode applied to the chroma block and (ii) the chroma block and a luma block that is co-located with the chroma block being coded in separate coding tree structures. The chroma block includes a first chroma subblock and a second chroma subblock. The processing circuitry determines a first block vector of the first chroma subblock and a second block vector of the second chroma subblock. The processing circuitry determines, based on the determined first block vector and the determined second block vector, whether to perform deblocking filtering on a subblock boundary between the first chroma subblock and the second chroma subblock. The processing circuitry reconstructs the chroma block based on the determination of whether to perform the deblocking filtering on the subblock boundary.

Deblock filtering a chroma block coded in an intra block copy mode

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

Method, apparatus, and system for parallel dynamic mesh alignment are provided. The process may include determining that a temporal alignment is present between one or more frames in a received input mesh including a plurality of polygons that describe a surface of a volumetric object, then, determining an intra-frame alignment scheme to spatially align charts within a frame. The process may also include applying the intra-frame alignment scheme to one or more corresponding charts in the one or more frames for inter-frame alignment; and processing the one or more frames in parallel based on the intra-frame alignment scheme and inter-frame alignment.

Parallel approach to dynamic mesh alignment

A plurality of neighboring vertices of a current vertex in a current frame of a mesh is determined. The current frame corresponds to the mesh at a first time instance. Each of the plurality of neighboring vertices is connected to the current vertex through a respective edge in the mesh. A plurality of neighboring estimation errors of the plurality of neighboring vertices is determined. Each of the plurality of neighboring estimation errors indicates a difference between a reference vertex of a corresponding one of the plurality of neighboring vertices in a reference frame and the corresponding one of the plurality of neighboring vertices in the current frame. The reference frame corresponds to the mesh at a second time instance. A prediction residue of the current vertex is determined based on the plurality of neighboring estimation errors. Prediction information of the current vertex is generated based on the determined prediction residue.

Temporal prediction based vertex position 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 reconstruct an area in a block in a current picture from a coded video bitstream. The block includes one or more coding blocks (CBs) in the current picture. After the reconstructing, the processing circuitry determines whether to update a previous local reference range for an intra block copy (IBC) mode based on a content of the reconstructed area and/or prediction information of the reconstructed area. In response to a determination not to update the previous local reference range for the IBC mode, the previous local reference range for the IBC mode is not updated. The processing circuitry decodes a coding block in the current picture using the IBC mode that is based on the previous local reference range, which does not include the reconstructed area.

Adaptive local reference range

Growing community of inventors

State College, PA, United States of America

Xiaozhong Xu