Tencent America LLC

Qualcomm Incorporated

Google Inc.

Tableau Software, Inc.

Apple Inc.

Trimble Inc.

Xin Zhao

Shan Liu

Liang Zhao

Xiang Yang Li

Madhu Peringassery Krishnan

Xiang Li

Marta Karczewicz

Yixin Du

Han Gao

Jianle Chen

Xiaozhong Xu

Guichun Li

Jing Ye

Li Feng Zhang

Vadim Seregin

Lien-Fei Chen

Wei-Jung Chien

Amir Said

Ying Hai Chen

Sehoon Yea

Cheung Auyeung

Meng Xu

Kai Zhang

Hongbin Liu

Stephan Wenger

Vijayaraghavan Thirumalai

Roman Chernyak

Biao Wang

Byeongdoo Choi

Samruddhi Yashwant Kahu

Xianglin Wang

Ling Li

Nan Hu

Yi-Wen Chen

Madhu Peringassery Krishna

Yushin Cho

Rajan Laxman Joshi

Hopil Bae

Paolo Sacchetto

Vidya Raghavan Setlur

Abbas Jamshidi Roudbari

Warren S Rieutort-Louis

Sunggu Kang

In Suk Chong

Marc Joseph DeVincentis

Hsiao-Chiang Chuang

Woo-Shik Kim

Mahdi Farrokh Baroughi

Steven E Molesa

Ding Ding

Alex Djalali

Chengjie Tu

Jaehong Chon

Jeffrey Ericson

Suyang Duan

Theodore Kornish

Tiffany T Moy

Francois R Jacob

Sandeep Chalasani

Zuoqian Wang

Eliana Leite Goldner

Sanaz Golbabaei

An Shi

Christoph Sachse

Lien-fei Chen

Jonathan P Mar

Ian D Tracy

Jui-Chih Liao

Tianqi Liu

Paul Stephen Drzaic

Yu-Chen Sun

Cheng-Teh Hsieh

Hilmi Enes Egilmez

Feng Zou

Sungwon Lee

Zhen Zhang

Niels Provos

Izhar Zahoor Ahmed

James Gerard Quaderer

Jaein Choi

Paul S Drzaic

Yong Sun

Anshi Liang

Guoxin Jin

Xiang Wang

Elmar Gehlen

Han-Chieh Chang

Izhar Z Ahmed

Aubrey Jason Calder

Moheeb Abu Rajab

Ying Chen

Pang Chao

A computing system receives a video bitstream comprising a current picture and a current block within the current picture. The current block is encoded using information from a first reference block and a second reference block. When a portion of the current block corresponds to a first area that is within reference boundaries in both of the first and second reference blocks, the system reconstructs the portion using an average of reference values from the first and second reference blocks. When the portion of the current block corresponds to (i) a second area that is not within the reference boundaries in both of the first and second reference blocks or (ii) a third area that is within the reference boundaries in only one of the first and second reference blocks, the system reconstructs the portion using a weighted average of respective values of the first and second reference blocks.

Implicit masked blending mode improvement

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 receives a coded video bitstream including a current picture. The current picture includes a current block. The processing circuitry determines, based on decoded information from the coded video bitstream, that the current block in the current picture is coded in an affine bi-prediction mode. The current block is predicted by a plurality of control point motion vectors. The processing circuitry refines the plurality of control point motion vectors by applying bilateral matching motion refinement, and reconstructs the current block according to the refined plurality of control point motion vectors associated with the current block.

Method for affine motion refinement

An example method of video decoding includes receiving a video bitstream that comprises a plurality of blocks including a current chroma block. When less than a threshold number of neighboring chroma blocks of a current chroma block use a chroma-from-luma (CfL) mode, a first context is selected as an entropy decoding context for a first flag. When at least the threshold number of neighboring chroma blocks use the CfL mode, a second context is selected as the entropy decoding context for the first flag. The method also includes entropy decoding the first flag from the video bitstream using the entropy decoding context, where the first flag indicates whether the CfL mode is enabled for the current chroma block, and decoding the current chroma block according to a value of the first flag.

Signaling method for chroma intra prediction mode

The various implementations described herein include methods and systems for encoding and decoding video. In one aspect, a method of video decoding includes receiving video data that includes a first block from a video bitstream, where the first block is predicted in an angular prediction mode. The method also includes identifying a set of reference samples for a portion of the first block using a prediction angle for the angular prediction mode and deriving a first angular prediction value for the portion using at least a first subset of the set of reference samples. The method further includes deriving a second angular prediction value for the portion using a weighted sum of at least a second subset of the set of reference samples and the first angular prediction value and decoding the portion using the second angular prediction value.

Systems and methods for angular intra mode coding

The various implementations described herein include methods and systems for coding video. In one aspect, a video bitstream includes distinct coding blocks of a current image frame and signals a cross-component intra prediction mode. A method includes for each distinct coding block, identifying a chroma component, a luma sample co-located with the chroma component, and neighboring luma samples of the luma sample. The method includes deriving a respective bias value based on a set of luma samples within a reference area of the respective coding block, which includes one or more coding blocks that are adjacent to, and decoded prior to, the respective coding block in the current image frame. The method further includes combining the luma sample, the neighboring luma samples, and the respective bias value to generate the chroma component and reconstructing the distinct coding blocks including the chroma component of each distinct coding block.

Bias value determination for chroma-for-luma (CfL) mode

Video processing devices and methods are disclosed to combine chroma blocks into a combined chroma block, determine neighbor luma samples of one or more luma blocks corresponding to the combined chroma block, average the reconstructed neighbor luma samples to generate a neighbor luma average, and perform a chroma from luma (CfL) prediction for the chroma blocks based on the neighbor luma average; and to compare a size of a chroma block with at least one size threshold and/or a transform unit (TU) depth of the chroma block with a TU depth of a corresponding luma block; determine a type of CfL prediction process for the chroma block based on the comparison; and perform a CfL prediction process for the chroma block according to the type of CfL prediction process.

Chroma from luma prediction based on merged chroma blocks

The various implementations described herein include methods and systems for coding video. In one aspect, a video bitstream includes a current coding block of an image frame and a syntax element for a cross-component intra prediction (CCIP) mode. The CCIP mode indicates whether each chroma sample of the current coding block is determined based on one or more luma samples. An electronic device generates a plurality of hypothesis values to be used in predicting a first chroma sample by combining a plurality of neighboring luma samples of a first luma sample that is co-located with the first chroma sample using a plurality of coefficients. The first chroma sample is predicted by combining the first luma sample and the plurality of hypothesis values based on a plurality of weighing factors. The electronic device reconstructs the current coding block including the first chroma sample.

Multi-hypothesis cross component prediction

Methods and apparatuses for performing cross-component intra prediction, including: receiving a coded bitstream; obtaining, from the coded bitstream, a syntax element indicating a downsampling filter used for a cross-component intra prediction mode; obtaining a plurality of reconstructed sample values of a first component which are associated with a pixel of a second component based on the downsampling filter; determining a pixel value of a downsampled pixel of the first component, based on the plurality of reconstructed sample values; determining a pixel value of the pixel of the second component based on the pixel value of the downsampled pixel of the first component; and reconstructing a picture based on the pixel value of the pixel of the second component.

Signaling of downsampling filters for chroma from luma intra prediction mode

The various implementations described herein include methods and systems for coding video. In one aspect, a method includes receiving video data comprising a current block, where the current block has a size of N×M pixels, N and M being positive integers. The method includes generating a prediction block larger than the current block for the current block, where the prediction block has a size of (N+W)×(M+W) pixels, W being a positive integer; and the method includes determining a window error for a sample window of a sample of the current block using the generated prediction block.

Systems and methods for window error estimation improvement in temporal filter

Aspects of the disclosure provide method and apparatus for video coding. In some examples, an apparatus includes processing circuitry. The processing circuitry decodes prediction information of a first block from a coded video bitstream. The first block is a non-square block and the prediction information for the first block is indicative of a first intra prediction mode in a first set of intra prediction modes for a square block. Then, the processing circuitry remaps the first intra prediction mode to a second intra prediction mode in a second set of intra prediction modes that is used for the non-square block. The second set of intra prediction modes includes at least the second intra prediction mode that is not in the first set of intra prediction modes. Further, the processing circuitry reconstructs at least one sample of the first block according to the second intra prediction mode.

Wide-angle intra prediction for non-square blocks

Aspects of the present disclosure provide methods and apparatuses for video encoding/decoding. In some examples, an apparatus includes processing circuitry that is configured to receive a coded video stream including a current block that is associated with a transform block, and determine whether a transform skip is used in the transform block. In response to a determination that the transform skip is not used in the transform block, the processing circuitry is configured to perform a first transform coefficient sign prediction in which (i) first signs of a first plurality of transform coefficients are predicted based on a first plurality of neighboring samples, and (ii) second signs of a second plurality of transform coefficients are predicted based on a second plurality of neighboring samples. The processing circuitry is further configured to reconstruct the current block based on the first plurality of transform coefficients and the second plurality of transform coefficients.

Coefficient sign prediction for transform skip

The various implementations described herein include methods and systems for coding video. In one aspect, a method includes receiving a video bitstream that includes encoded video data; obtaining information indicating two or more different clipping ranges for the encoded video data; deriving the two or more different clipping ranges based on the obtained information; performing a first clipping operation on a first portion of the encoded video data based on a first clipping range of the two or more different clipping ranges; and performing a second clipping operation on a second portion of the encoded video data based on a second clipping range different from the first clipping range.

Different ranges for clipping processes for video and image compression

A method, system, and non-transitory computer readable medium is provided for decoding video data. Video data comprising a chroma component having a first nominal angle and first delta angles and a luma component having a second nominal angle and second delta angles is received, wherein the first delta angles are dependent on the second delta angles. The first delta angle values corresponding to the first delta angles are parsed or derived based at least on second delta values corresponding to the second delta angles, wherein the first delta angle values are derived from one or more nominal angles associated with one or more sample positions corresponding to one or more luma blocks. A prediction mode associated with the chroma component based on a nominal mode of a corresponding luma block is entropy-coded. The video data is decoded based on the first delta angle values corresponding to the first delta angles.

Further improvement for chroma mode coding

Methods, apparatus, and computer readable storage medium for intra prediction mode coding in video decoding. The method includes receiving, by a device, a coded video bitstream for a block. The device includes a memory storing instructions and a processor in communication with the memory. The method also includes dividing, by the device, a list of intra modes into a plurality of intra mode sets for the block based on mode information of each intra mode in the list, the list of intra modes corresponding to an intra prediction mode of at least one neighboring block of the block; extracting, by the device from the coded video bitstream, a set index indicating an intra mode set from the plurality of intra mode sets; extracting, by the device from the coded video bitstream, a mode index indicating an intra prediction mode from the intra mode set; and determining, by the device, the intra prediction mode for the block based on the set index and the mode index.

Intra mode coding

This disclosure relates generally to video coding/decoding and particularly to motion vector prediction based on subblock motion vectors. One method is disclosed for processing a current block of a current frame in a coded video bitstream. The method includes receiving, by a device, a coded video bitstream; determining, by the device based on the coded video bitstream, the current block of the current frame to be inter predicted by at least one reference block of at least one reference frame; determining, by the device based on the coded video bitstream, a current-block motion vector (MV) corresponding to each of the at least one reference block, the current-block MV to be predicted by a reference MV; and identifying, by the device, a subblock MV of a MV reference block as the reference MV for predicting the current-block MV.

Method and apparatus for motion vector prediction based on subblock motion vector

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San Diego, CA, United States of America

Xin Zhao