Tencent America LLC

Hfi Innovation Inc.

Mediatek Corporation

Roku, Inc.

Future Wei Technologies, Inc.

Sap Se

Mediatek Singapore Pte. Ltd.

Huawei Technologies Co., Limited

Jing Ye

Shan Liu

Liang Zhao

Xin Zhao

Xiaozhong Xu

Han Gao

Xiang Yang Li

Tzu-Der Chuang

Jungsun Kim

Wang-Lin Lai

Yu-Chen Sun

Ching-Yeh Chen

Guichun Li

Stephan Wenger

Xiang Li

Shaw-Min Lei

Ronica Jethwa

Yu-Wen Huang

Cheung Auyeung

Byeongdoo Choi

Yu Wang

Wei W Wang

Weijia Zhu

Jicheng An

Fei Xiao

Abhishek Bambha

Nam Vo

Zidong Wang

Jose Sanchez

Yushin Cho

Khaldun Aidarabsah

Jing Lu

Tianqi Liu

Madhu Peringassery Krishnan

Haoping Yu

Meng Xu

Yue Chen

Xiaoyun Zhu

Bin Zhu

Rohit Mahto

Zhan Ma

Yann Le Biannic

Prerna Makanawala

Prajesh K

Lian Liu

Pulkit Aggarwal

Xian Wang

Daniel Chen

Karthik S J

Anirban Das

Amy He

Jinzhong Zhang

Subhobrata Dey

Georg Glantschnig

Xiaoqing He

Arjun Karat

Riya Thosar

Huichao Zhao

Sid Askary

Cj Hersh

Shu Zhang

Wei Wang

Kai Zhang

Systems and methods for encoding and decoding using syntax design for multi-symbol arithmetic coding are provided. A method includes receiving a coded video bitstream including a plurality of syntax elements; determining a first maximum alphabet size for arithmetic coding by an arithmetic coding engine, the first maximum alphabet size determined based on a hardware constraint; determining a second maximum alphabet size that is less than the first maximum alphabet size; and decoding the plurality of syntax elements included in the coded video bitstream, based on the determined second maximum alphabet size, wherein each of the plurality of syntax elements is entropy coded with an alphabet size less than or equal to the determined second maximum alphabet size.

Systems and methods including syntax design for multi-symbol arithmetic coding

An example method of video coding includes receiving a video bitstream including a plurality of coding blocks; identifying, based on a first indicator in the video bitstream, a coding region that comprises two or more blocks of the plurality of coding blocks, where at least one block in the coding region is encoded in an intra prediction mode and at least one block in the coding region is encoded in a non-intra prediction mode. For a last block in the coding region, when all preceding blocks in the coding region are encoded in the intra prediction mode, the method includes inferring a prediction mode of the last block as being an inter prediction mode without receiving an inter prediction mode indicator for the last block; and reconstructing the last block using the inferred prediction mode.

Systems and methods for implicit derivation in a recursive intra region

Various implementations described herein include methods and systems for coding video. In one aspect, a video bitstream includes a high level syntax element for a frame level cross-component sample offset (CCSO) flag indicating whether to apply CCSO filtering on a current image frame. When the frame level CCSO flag indicates that CCSO filtering is applied the current image frame, an electronic device identifies, in the video bitstream, a first syntax element for a first component CCSO flag indicating whether to apply CCSO filtering on a first color component of the current image frame, and determines whether to apply CCSO filtering on a first color sample of the first color component based on the first syntax element. The current image frame including the first color sample of the first color component is reconstructed.

CCSO with high level flags

The various implementations described herein include methods and systems for coding video. In one aspect, a method of video decoding includes receiving video data that includes a first block and a plurality of residual coefficients, from a video bitstream. The first block is encoded in an intra prediction mode, and the plurality of residual coefficients are generated by applying a short distance intra prediction to a residue block for the first block. The residue block generated from applying the intra prediction mode to the first block. The method includes generating, from the plurality of residual coefficients, a refined residue block for the first block, and generating a reconstructed residue block for the first block, where the reconstructed residue block is generated using an intra prediction block and the refined residue block. The method also includes reconstructing the first block using the refined residue block.

Short distance predictions for residual blocks

Coded information of a current block and neighboring blocks of the current block is received, where the current block is predicted in an intra directional mode. The intra directional mode of the current block is determined to be associated with an angle that is one of smaller than 90 degrees and larger than 180 degrees. In response to the intra directional mode of the current block being associated with the angle, whether a delta angle associated with the current block is a pre-defined delta angle is determined. In response to the delta angle associated with the current block not being the pre-defined delta angle, a single direction intra prediction and not a bi-direction intra prediction is applied to the current block. A sample of the current block is reconstructed based on an adjacent reference sample on a reference line that is determined according to the single direction intra prediction.

Angular intra prediction

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

Various implementations described herein include methods and systems for coding video. In one aspect, a video bitstream includes a current image frame and a first syntax element. An electronic device determines that the first syntax element has a first predefined value indicating that the cross-component sample offset (CCSO) mode is enabled, and generates a set of adapted luma samples including an adapted first luma sample and its adapted neighboring luma samples based on a set of reconstructed luma samples. The reconstructed luma samples include a first luma sample that is collocated with a first color sample. The electronic device determines the first sample offset of the first color sample based on the adapted first luma sample and the one or more adapted neighboring luma samples. The current image frame is reconstructed at least by adjusting the first color sample based on the first sample offset.

CCSO with downsampling filters and sample position selection

This disclosure describes aspects of advanced video coding technologies and is particular related to cross-component sample offset (CCSO) filtering of reconstructed samples. For example, a quantizer for quantizing sample deltas in order to apply a CCSO filter may be constructed as an asymmetric quantizer with respect to zero sample delta. Either a symmetric or an asymmetric quantizer may be selected for processing sample deltas prior to applying a CCSO filter. An asymmetric quantizer may relate to a corresponding symmetric quantizer by a non-zero offset. Signaling of a selection of an asymmetric quantizer may be provided separately from or dependent on a signaling of a symmetric quantizer.

Cross component sample offset filtering with asymmetric quantizer

This disclosure relates generally to video coding and particularly to methods and systems for deriving context adaptive interpolation filter used for generating prediction samples in inter prediction involving a fractional motion vector or block vector. For example, an encoder and a decoder may derive interpolation filters adaptively using reconstructed samples. The reconstructed samples may belong to templates near a current block and a reference block related by the motion vector or block vector. The derivation of the adaptive interpolation filters may be based on minimizing distortions between interpolated templates associated with the reference block and the templates associated with the current block.

Context adaptive interpolation filter

Methods and apparatuses for performing chroma from luma (CfL) intra prediction, including: receiving a current chroma block from a coded bitstream; determining whether CfL intra prediction mode is enabled for the coded bitstream; determining a color format corresponding to the coded bitstream; based on determining that the CfL intra prediction mode is enabled, and based on the determined color format, obtaining, from the coded bitstream, a syntax element indicating a downsampling filter used for the CfL intra prediction mode; selecting the downsampling filter among a plurality of downsampling filters to be used for a chroma block in the CfL intra prediction mode; determining luma sample positions associated with the current chroma block based on the selected downsampling filter; downsampling a plurality of luma samples at the luma sample positions, wherein pixels in each downsampled luma sample are co-located with corresponding pixels in the current chroma block; and reconstructing the current chroma block based on at least the plurality of downsampled luma samples.

Signaling of downsampling filters for chroma from luma intra prediction mode

This disclosure generally describes a set of advanced video coding technologies, and is specifically related to cross-component sample offset (CCSO) filtering. For example, a CCSO filter having fractional CCSO filtering tap positions may be used to generate sample offsets from one color component of a reconstructed video. The sample offsets may then be applied to a second color component of the reconstructed video. The reconstructed samples of the first color component may first be interpolated by an interpolation filter in order to generate interpolated samples of the first color component at the fractional CCSO tap positions. The interpolated samples may be used as input to the CCSO filter for the generation of the sample offsets.

Cross component sample offset filtering with interpolated filter taps

This disclosure relates generally to video coding/decoding and particularly for a transform dictionary. A method includes receiving the coded video bitstream; determining, based on the coded video bitstream, a transform pile for the current block, the transform pile being one transform pile in a transform dictionary, the transform dictionary comprising a plurality of transform piles, and the transform pile comprising a plurality of transform sets; determining a transform set in the transform pile; determining a transform kernel in the transform set; performing an inverse transform for the current block based on the transform kernel for obtaining a residual block for the current block; and reconstructing the current block based on the residual block.

Dictionary of transforms

This disclosure relates generally to video coding/decoding and particularly for providing extension to block adaptive weighted prediction (BAWP). One method includes receiving a coded video bitstream; determining, based on a syntax element signaled in the coded video bitstream, a prediction mode for predicting the current block based on a reference block, wherein the prediction mode comprises a linear equation; deriving a scaling factor for the current block, from at least one of the following: multiple scaling factors of neighboring blocks with respect to the current block, or a stored scaling factor bank; and reconstructing the current block based on the reference block and the identified scaling factor according to the linear equation.

Extension to block adaptive weighted prediction

Processing circuitry receives, from a coded video bitstream, coded information of a current coding block in a current picture. The coded information is indicative of a directional intra prediction of the current coding block. The processing circuitry determines an index to an entry in an angle-to-offset mapping lookup table according to the coded information of current coding block. The angle-to-offset mapping lookup table stores a set of derivative values that are associated with angles, the set of derivative values includes two or more integers that are powers of two. The processing circuitry accesses the entry to obtain a derivative value, determines, for a pixel in the current coding block, an offset indicative of a reference location in the current picture according to the derivative value and a location of the pixel, and reconstructs the pixel in the current coding block based on the reference location in the current picture.

Refined intra prediction angles

This disclosure relates to video processing that includes iteratively predicting a chroma block in a Chroma from Luma (CfL) prediction mode based on downsampled luma samples downsampled from a plurality of downsampling filters, and selecting a target downsampling filter from the plurality of downsampling filters that corresponds to an error score determined for the iteratively predicting.

Selecting downsampling filters for chroma from luma prediction

Growing community of inventors

San Jose, CA, United States of America

Jing Ye