Tencent America LLC

Qualcomm Incorporated

Apple Inc.

Google Inc.

Tableau Software, Inc.

Trimble Inc.

Xin Zhao

Shan Liu

Liang Zhao

Xiang Yang Li

Madhu Peringassery Krishnan

Xiang Li

Marta Karczewicz

Yixin Du

Han Gao

Jing Ye

Xiaozhong Xu

Guichun Li

Jianle Chen

Li Feng Zhang

Lien-Fei Chen

Vadim Seregin

Wei-Jung Chien

Amir Said

Ying Hai Chen

Sehoon Yea

Cheung Auyeung

Meng Xu

Roman Chernyak

Kai Zhang

Biao Wang

Hongbin Liu

Stephan Wenger

Vijayaraghavan Thirumalai

Samruddhi Yashwant Kahu

Byeongdoo Choi

Xianglin Wang

Ling Li

Nan Hu

Yushin Cho

Yi-Wen Chen

Tianqi Liu

Madhu Peringassery Krishna

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

Mahdi Farrokh Baroughi

Woo-Shik Kim

Hsiao-Chiang Chuang

Steven E Molesa

Ding Ding

Alex Djalali

Chengjie Tu

Jaehong Chon

Jeffrey Ericson

Elmar Gehlen

Tiffany T Moy

Francois R Jacob

Suyang Duan

Theodore Kornish

Sandeep Chalasani

Eliana Leite Goldner

Sanaz Golbabaei

Zuoqian Wang

Jonathan P Mar

An Shi

Christoph Sachse

Jui-Chih Liao

Ian D Tracy

Lien-fei Chen

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

Han-Chieh Chang

Moheeb Abu Rajab

Aubrey Jason Calder

Izhar Z Ahmed

Pang Chao

Ying Chen

James G Quaderer

A video bitstream including a current transform block (TB) in a current picture is received. A context model is determined for a syntax element associated with a transform coefficient level of a first coefficient group (CG) in the current TB based on transform coefficient levels of at least one first neighboring CG of the first CG. The first CG is positioned on a first scanning line. The at least one first neighboring CG is positioned on a second scanning line that is scanned before the first scanning line. The context model is a probability model for a non-separable transform. The first CG is reconstructed based on the transform coefficient level that is determined according to the determined the context model.

Context derivation for arithmetic coding of transform coefficients generated by non-separable transforms

The various embodiments described herein include methods and systems for encoding and decoding video. In one aspect, a method includes receiving video data comprising a plurality of blocks, including a first block. The method also includes obtaining, from the video data, a syntax element value indicating a wedge mode index corresponding to a first partition mode from a plurality of partition modes for the first block, where the wedge mode index is greater than 16. The method further includes determining that the first partition mode is associated with a compound wedge-based prediction for the first block. The method also includes partitioning the first block into a first section and a second section in accordance with the first partition mode and the wedge mode index, and decoding the first section in accordance with a first predictor and decoding the second section in accordance with a second predictor.

Systems and methods for wedge-based prediction mode signaling

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. The first syntax element has a first predefined value that indicates that the band offset only mode is enabled to determine a first sample offset of a first color sample based on luma samples, independently of any associated luma gradient of the luma samples. When the band offset only mode is enabled, quantized values are generated based on the luma samples including a first luma sample collocated with the first color sample. A first color sample is classified based on the quantized values to determine the first sample offset of the first color sample. The current image frame is reconstructed at least by adjusting the first color sample based on the first sample offset.

CCSO with band offset only option

A video bitstream including coding information of a current block in a current picture is received, where the coding information indicates that the current block is coded with an intra template matching prediction mode. At least one template for predicting the current block is determined. Each of the at least one template is a respective candidate template of a plurality of template types available in the intra template matching prediction mode. The candidate templates are associated with one of a shape of the current block, a size of the current block, an intra prediction mode of the current block, and distances between the current block and the candidate templates of the plurality of template types. The candidate templates include different combinations of neighboring reconstructed samples. The current block is reconstructed using template match in the intra template matching prediction mode based on the determined at least one template.

Multi-template based intra-frame template matching prediction

Aspects of the disclosure provide a method and an apparatus including processing circuitry for video decoding. The processing circuitry can be configured to determine a transform skip for a transform block (TB) is in one direction. The processing circuitry can be configured to quantize transform coefficients in the TB based on a plurality of quantization steps. First transform coefficients in the TB can be quantized based on a smallest of the plurality of quantization steps. The first transform coefficients in the TB include one of a first row and a first column of the transform coefficients in the TB that has a DC spatial frequency, the one of the first row and the first column being along the one direction of the transform skip. Further, the processing circuitry can be configured to perform a transform on the quantized transform coefficients in the TB.

Quantizer for one-dimensional transform skip

An example method includes receiving a video bitstream comprising a plurality of coding blocks. The method includes identifying, based on a first indicator in the video bitstream, a coding region that comprises two or more luma blocks and two or more chroma blocks. A subset of luma blocks in the coding region is encoded in a first prediction mode. Each chroma block in the coding region is encoded in a second prediction mode. The method includes applying a first partitioning to the two or more luma blocks in the coding region. The method includes applying a second partitioning for the two or more chroma blocks in the coding region. The method includes reconstructing the coding region using the first partitioning and the second partitioning.

Systems and methods for recursive inter region partitioning

Methods and apparatuses for performing cross-component intra prediction, including: receiving a current chroma block from a coded bitstream; determining, from the coded bitstream, that a scaling factor used for the current chroma block in a chroma for luma (CfL) intra prediction mode; deriving a predicted scaling factor based on first neighboring samples of the current chroma block and second neighboring samples of a luma block that is co-located with the current chroma block; using the predicted scaling factor as the scaling factor used for the current chroma block in the CfL intra prediction mode; reconstructing the current chroma block after scaling the current chroma block based on the predicted scaling factor.

Signaling method for scaling parameter in chroma from luma intra prediction mode

The various embodiments described herein include methods and systems for coding video. In one aspect, a method includes obtaining video data comprising a plurality of blocks, including a first block. The method further includes determining a plurality of transform coefficients associated with the first block; and selecting a subset of the plurality of transform coefficients based on a frequency corresponding to each transform coefficient of the plurality of transform coefficients. The method also includes predicting respective coefficient signs for selected subset of the transform coefficients associated with the first block based on respective context information; and reconstructing the first block based on the plurality of transform coefficients and the predicted respective coefficient signs.

Systems and methods for frequency-dependent coefficient sign coding

This disclosure relates generally to video coding and particularly to methods and systems for signaling of compound inter prediction modes. For example, a correlation between a use of optical flow refinement and various compound inter prediction modes is explored to design example schemes for signaling an optical flow refinement flag and a compound inter prediction mode for a video block. Specifically, the signaling of the inter prediction modes for a block may depend on whether the optical flow refinement is applied to the block or not.

Method and apparatus for signaling for compound inter prediction modes

A method includes receiving a bitstream of coded information for a sequence of pictures, the coded information indicates an inter prediction of a current block in a current picture using a formular based inter prediction technique, the formular based inter prediction technique generates a prediction sample of the current block based on a formular with reconstructed samples of a reference block in a reference picture being input to the formular, the formular includes parameters derived based on a current template of the current block and a reference template of the reference block. The method also includes constructing a candidate list including one or more coded blocks associated with the current block, a coded block in the one or more coded blocks is a candidate that provides formular based inter prediction information.

On list construction of coded information of inter prediction

Aspects of the disclosure include methods and apparatuses for video coding. One of the apparatuses includes processing circuitry that receives a bitstream of a current block in a current picture. The current block is coded with a directional nearest neighbor prediction (DNNP) mode. The processing circuitry selects a prediction value for a sample in the current block from a top-left value, a top value, or a left value based on one or more difference values between respective paired values of (i) the top-left value associated with a top-left reference sample that is a top-left neighbor of the current block, (ii) the top value associated with a top reference sample that is a top neighbor of the sample in the current block, and (iii) the left value associated with a left reference sample that is a left neighbor of the sample in the current block. The processing circuitry reconstructs the current block using the selected prediction value for the sample in the current block.

Directional nearest neighbor prediction mode

Processing circuitry receives coded information of a motion vector difference (MVD). The processing circuitry calculates cost values associated with value combinations for a plurality of bits in coding bits of the MVD, at least one of the plurality of bits is a bit in a codeword for indicating a magnitude for the MVD. The processing circuitry determines a combination of prediction values for the plurality of bits from the value combinations, the combination of prediction values is associated with a lowest cost value in the cost values. The processing circuitry decodes the coded information of the MVD to obtain one or more indicators for the combination of prediction values, the one or more indicators indicates whether the plurality of bits is correctly predicted by the combination of prediction values. The processing circuitry determines the MVD based on the combination of prediction values and the one or more indicators.

Method and apparatus for motion vector coding

Processing circuitry receives a video bitstream comprising a current coding block in a picture coded in a template-based multiple reference line intra prediction (TMRL) mode. The processing circuitry determines combinations of reference lines and intra prediction modes for the current coding block. A first combination in the combinations includes a first reference line and a first intra prediction mode. For the first combination, the processing circuitry calculates template entry delta values respectively associated with entries of a template of the current coding block based on the first reference line and the first intra prediction mode, and calculates a first template matching cost value by unequal weighting of the template entry delta values. The processing circuitry sorts the combinations according to template matching cost values respectively associated with the combinations, selects a specific combination from the sorted combinations, and reconstructs the current coding block according to the specific combination.

Template matching for multiple reference line intra prediction

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 signals a syntax element for a cross-component prediction (CCP) mode. When the CCP mode is enabled, a computing system identifies a reference area of the current coding block and downsamples the reference area to identify samples of a subset of reference area. A plurality of model parameters used in the CCP mode are determined for a first chroma sample of the current coding block based on the samples of the subset of reference area. The computing system combines a set of one or more luma samples (e.g., of a reference coding block) using the plurality of model parameters to generate the first chroma sample. The image frame is reconstructed based on the current coding block including the first chroma sample.

Model parameter derivation for prediction modes based on least mean square optimization

The various implementations described herein include methods and systems for coding video (e.g., decoding video data). In one aspect, a method includes identifying, in a current frame, a current coding block and one or more neighboring coding blocks. The current coding block has a first luma sample. The method further includes identifying a plurality of candidate luma samples within the one or more neighboring coding blocks for the first luma sample. The one or more neighboring coding blocks are coded in 4:2:0 chroma color format. The method further includes identifying a target luma sample among the plurality of candidate luma samples including a 2×2 luma block and determining a first chroma sample co-located with the first luma sample based on a target chroma sample co-located with the target luma sample in the one or more neighboring coding blocks.

Systems and methods for determining chroma samples in an intra prediction mode of video coding

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San Diego, CA, United States of America

Xin Zhao