Tencent America LLC

Qualcomm Incorporated

Hefei Reliance Memory Limited

Lightwave Microsystems Corporation

Other

Neophotonics Corporation

Samsung Electronics Co., Ltd.

Lightwave Microsytstems Corporation

Liang Zhao

Shan Liu

Xin Zhao

Xiang Yang Li

Xiang Li

Han Gao

Yixin Du

Jing Ye

Zhichao Lu

Jordan C Cookman

Cheng-Han Wang

Madhu Peringassery Krishnan

Angelica Wong

Hong Sun Kim

Xiaozhong Xu

Guichun Li

Cheung Auyeung

Jie Wu

Le Nguyen Luong

Michael Kohlmann

Jin-Su Ko

Leena Zacharias

Parvathanathan Subrahmanya

Rayman Wai Pon

Fan Zhong

Krishnaranjan Rao

Pranav Iyengar

Daniel Carolin

Arnaud Meylan

Reza Shahidi

Amir Aminzadeh Gohari

Cormac S Conroy

Amit Mahajan

Chun-Hao Hsu

Roger Brockenbrough

Nitin Pant

Hao Xu

Vieri Vanghi

Kenneth McGreer

I-Hsiang Lin

Jeffrey Wong

Dinesh Kumar Devineni

Chang Shik Row

Jane Lam

Stephan Wenger

Leonid Sheynblat

Douglas Neal Rowitch

Daniel Fred Filipovic

Xiaoxin Zhang

Arnold Jason Gum

Dinesh Jagannath Alladi

Prasad Srinivasa Siva Gudem

Yi Zeng

Kentaro Yamamoto

David Loweth Winslow

Farnaz Parhami

Jongik Won

Balasubramanian Sivakumar

Paul A Conflitti

Sean Baker

Zhijie Xiong

Shishir Gupta

Calvin Ka Kuen Ho

Zhigang Han

Santosh Kumar Gupta

Jean-Pierre Raffegeau

Byeongdoo Choi

Aziz Gholmieh

Ling Li

Brian Clarke Banister

Dominic Gerard Farmer

Bhushan Shanti Asuri

Aristotele Hadjichristos

Roland Reinhard Rick

Shrenik Patel

Tevfik Yucek

Francis M Ngai

Feng Lu

Prashant Udupa Sripathi

Subramanya P Rao

Prashanth Akula

Kevin Hsi Huai Wang

Ming Yan

Koorosh Akhavan

Carl Hardin

Anup Savla

Arun Somani

Thomas S Tarter

Siva Penke

Anil Sahai

Emanuele Lopelli

Chan Hong Park

Calvin Ho

Wilson Long

Rishabh Raj

Shriram Gurumoorthy

Ravindra Chauhan

Brian P McGinnis

David James Quirke

Wayne Wai Wing Lui

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 coded information of a current block in a current picture from a coded video bitstream. The coded information includes a syntax element associated with the current block, the syntax element indicates a decoding parameter of the current block. The processing circuitry determines a context-based adaptive binary arithmetic coding (CABAC) context model associated with the syntax element based on at least a temporally co-located block of the current block. The temporally co-located block is in a different picture from the current picture. Further, the processing circuitry decodes the syntax element based on the CABAC context model, and reconstructs the current block based on the syntax element that is decoded based on the CABAC context model.

Context-based adaptive binary arithmetic coding (CABAC) context modeling with information from temporal neighbors

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 describes a set of advanced video coding technologies. More specifically, the disclosed technology involves cross-channel prediction and particularly chroma from luma (CfL) prediction. In some example implementations, a sample in a chroma channel is predicted based on a weighted sum or average of an alternate current prediction contribution derived based on reconstructed samples of a luma channel and a direct current prediction contribution generated based on an intra-prediction of the sample in the chroma channel based on reconstructed samples of the chroma channel, the intra-prediction being performed based on an intra-prediction mode other than a DC mode.

Cross-channel prediction based on multiple prediction modes

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

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

This disclosure relates generally to video coding/decoding and particularly for implicitly indicating motion vector predictor precision. One method includes receiving a coded video bitstream; determining, based on the coded video bitstream, a current block of a current frame to be inter predicted by at least one reference block of at least one reference frame; determining, based on the coded video bitstream, a motion vector (MV) of the current block to be predicted by a motion vector predictor (MVP) and a corresponding motion vector difference (MVD); determining an MVP precision according to an implicit indication, a pre-defined rule, or a high-level syntax, wherein an MVD precision associated with the corresponding MVD is different from the MVP precision; and reconstructing, by the device, the current block based at least on the MVP at the determined MVP precision and the MVD at the MVD precision that is different from the MVP precision.

Method and apparatus for implicitly indicating motion vector predictor precision

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

A method, computer program, and computer system are provided for encoding video data. Luma and chroma samples are identified from image data corresponding to a video frame. In particular, at least one chroma sample may be predicted from at least one luma sample based on a DC contribution from a chroma component of the image data and an AC contribution from a luma component of the image data. Also, a plurality of linear models may be determined from the identified luma and chroma samples. The luma and chroma samples may be classified into a number of categories corresponding to a number of linear models, where each category has at least one corresponding linear model parameters signaled to the bitstream; the chroma sample prediction may be further based on such parameters.

Multiple linear models employed with chroma-from-luma prediction

This disclosure relates to adaptive loop filtering (ALF) for cross-component sample offset (CCSO), local sample offset (LSO), and generalized sample offset (GSO). ALF uses reconstructed samples of a first color component as input (e.g., Y or Cb or Cr). At least one of the GSO, LSO, or CCSO is determined to be enabled for a frame based on a syntax value in a coded video stream. The coded video stream is decoded by applying the at least one of the GSO, the LSO, or the CCSO at a block level.

Adaptive application of generalized sample offset

This disclosure relates to video processing that includes: determining that a chroma block is to be predicted in a Chroma from Luma (CfL) mode, wherein the chroma block corresponds to a luma block; mapping a plurality of luma samples of the luma block to a plurality of neighbor chroma samples in at least one neighbor chroma block that neighbors the chroma block; and performing a CfL prediction of the chroma block using the plurality of neighbor chroma samples as a plurality of prediction samples of the chroma block. This disclosure also relates to video processing that includes: determining a type of chroma from luma (CfL) prediction process from among a plurality of different types of CfL prediction processes; and performing a CfL prediction process according to the type of CfL prediction process.

Chroma from luma prediction using mapping and different types

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

This disclosure relates generally to video coding and particularly to methods and systems for determining context for coding and decoding various syntax elements of a video stream in inter prediction modes. Various example implementations are disclosed for limiting numbers of possible coding contexts for syntax elements related to the inter prediction mode, and for selecting coding contexts for a current block based on coding information of spatially neighboring blocks and temporal motion prediction information.

Context design for coding and decoding syntax elements in inter prediction modes

Growing community of inventors

Sunnyvale, CA, United States of America

Liang Zhao