Qualcomm Incorporated

Vid Scale, Inc.

Interdigital Vc Holdings, Inc.

Yan Zhang

Marta Karczewicz

Vadim Seregin

Han Huang

Dmytro Rusanovskyy

Zhi Zhang

Chun-Chi Chen

Yan Ye

Xiaoyu Xiu

Yuwen He

Yao-Jen Chang

Wei-Jung Chien

Jianle Chen

Adarsh Krishnan Ramasubramonian

Muhammed Zeyd Coban

Nan Hu

Cheng-Teh Hsieh

Shanshan Wang

Hongtao Wang

Martin Saint-Laurent

Shiau-He Tsai

Yong Xie

Kevin Pascal Andre Reuze

Song Tian

Jie Mao

Ling Xie

Huichun Chen

An example device for decoding video data includes a memory configured to store video data; and a processing system including one or more processors implemented in circuitry, the processing system being configured to: determine that a previously coded block of video data was coded using uni-prediction mode for which a bi-prediction syntax element is not assigned a value; determine that a current block of the video data is to be coded using a bi-prediction mode and that motion information of the current block is to be predicted from the previously coded block, including from the bi-prediction syntax element of the previously coded block; and in response to the bi-prediction syntax element of the previously coded block not having an assigned value, decode the current block using a substitute value for the bi-prediction syntax element.

Using substitute motion information when coding video data

Encoding and decoding video data using an affine decoder side motion vector derivation (DMVR) mode includes receiving a block of video data to be decoded using the affine DMVR mode, and dividing the block into a plurality of subblocks. A video encoder and video decoder may determine a final offset for the affine DMVR mode using a first subset of the plurality of subblocks. The video encoder and decoder may code the block of video data using the final offset to generate a coded block of video data.

Methods of subblock skipping for affine motion search for video coding

An example device for coding video data includes memory configured to store the video data and one or more processors communicatively coupled to the memory. The one or more processors are configured to reduce a bit length of one or more input variables for a linear regression operation to generate one or more reduced bit length input variables, the input variables including at least one of a) one or more delta coordinates, b) one or more delta motion vectors, or c) a value representing a number of subblocks. The one or more processors are configured to perform the linear regression operation and derive an affine motion model based on the performing the linear regression on the one or more reduced bit length input variables. The one or more processors are configured to code a current block of the video data based on the affine motion model.

Bit-length control for linear regression-based affine merge candidate derivation

A method for coding a block of video data using affine mode includes determining a refined affine model for the current block of video data from a linear regression process using a base motion vector field and a guidance motion vector field as inputs to the linear regression process. The method further includes determining affine merge candidates for the current block using the refined affine model, and coding the current block of video data using the affine merge candidates.

Derivation of affine merge candidates with linear regression for video coding

A device for decoding video data includes a memory configured to store video data; and one or more processors implemented in circuitry and configured to: determine that a boundary block of a picture of the video data is bi-directional inter-predicted using a first motion vector and a second motion vector, the boundary block having an edge that touches an edge of the picture; decode the picture, including decoding the boundary block; form a first intermediate padding block using the first motion vector; form a second intermediate padding block using the second motion vector; form a padding block using the first intermediate padding block and the second intermediate padding block; and assign padding values of the padding block to a padding region of the picture neighboring the boundary block on an opposite side of the edge of the picture.

Bi-directional prediction boundary pixel padding with out-of-picture-boundary motion vectors

An example device includes memory configured to store the video data and one or more processors implemented in circuitry and communicatively coupled to the memory. The one or more processors are configured to determine at least one of a temporal candidate or a history-based candidate and determine at least one non-adjacent candidate, wherein the at least one non-adjacent candidate is from a unit that is not adjacent to a current prediction unit (PU). The one or more processors are configured to determine an advanced motion vector predictor (AMVP) candidate list including the at least one of the temporal candidate or the history-based candidate and the at least one non-adjacent candidate. The at least one non-adjacent candidate is added to the AMVP candidate list after the temporal candidate or before the history-based candidate. The one or more processors are configured to code the current PU based on the AMVP candidate list.

Template matching-based advanced motion vector predictor (AMVP) candidate list construction with non-adjacent candidates and AMVP index signaling

A video encoder and video decoder may determine to enable or disable a template-based inter prediction technique based on whether reference picture resampling or weighted prediction are used. A video encoder and video decoder may determine that a reference picture resampling mode is enabled. determine not to apply a template-based inter prediction technique to the video data based on the reference picture resampling mode being enabled, and code the video data using inter prediction without applying the template-based inter prediction technique.

Interaction between reference picture resampling and template-based inter prediction techniques in video coding

A device for decoding video data includes a memory configured to store video data; and one or more processors implemented in circuitry and configured to: determine a deterministic bounding box from which to retrieve reference samples of reference pictures of video data for performing decoder-side motion vector derivation (DMVD) for a current block of the video data; derive a motion vector for the current block according to DMVD using the reference samples within the deterministic bounding box; form a prediction block using the motion vector; and decode the current block using the prediction block.

Using unrefined motion vectors for performing decoder-side motion vector derivation

Exemplary embodiments include systems and methods for coding a video comprising a plurality of pictures including a current picture, a first reference picture, and a second reference picture, where each picture includes a plurality of blocks. In one method, for at least a current block in the current picture, a number of available bi-prediction weights is determined based at least in part on a temporal layer and/or a quantization parameter of the current picture. From among available bi-prediction weights a pair of weights are identified. Using the identified weights, the current block is then predicted as a weighted sum of a first reference block in the first reference picture and a second reference block in the second reference picture. Encoding techniques are also described for efficient searching and selection of a pair of bi-prediction weights to use for prediction of a block.

Generalized bi-prediction for video coding with reduced coding complexity

A method of decoding video data may comprise determining merge candidates for a block of video data and determining if a merge candidate of the merge candidates includes an additional inter prediction signal. If a merge candidate includes an additional inter prediction signal, the method may include disabling at least one decoder side motion vector derivation technique for use on a base prediction signal of the block of video data.

Multiple inter predictors with decoder side motion vector derivation for video coding

Overlapped block motion compensation (OBMC) may be performed for a current video block based on motion information associated with the current video block and motion information associated with one or more neighboring blocks of the current video block. Under certain conditions, some or all of these neighboring blocks may be omitted from the OBMC operation of the current block. For instance, a neighboring block may be skipped during the OBMC operation if the current video block and the neighboring block are both uni-directionally or bi-directionally predicted, if the motion vectors associated with the current block and the neighboring block refer to a same reference picture, and if a sum of absolute differences between those motion vectors is smaller than a threshold value. Further, OBMC may be conducted in conjunction with regular motion compensation and may use simplified filters than traditionally allowed.

Complexity reduction of overlapped block motion compensation

An example device includes memory configured to store video data and one or more processors coupled to the memory. The one or more processors are configured to apply a multi-pass DMVR to a motion vector for a block of the video data to determine at least one refined motion vector and decode the block based on the at least one refined motion vector. The multi-pass DMVR includes a block-based first pass, a sub-block-based second pass, and a sub-block-based third pass.

Multi-pass decoder-side motion vector refinement

A video decoder can be configured to determine that a current block in a current picture of the video data is coded in an affine prediction mode; determine one or more control-point motion vectors (CPMVs) for the current block; identify an initial prediction block for the current block in a reference picture using the one or more CPMVs; determine a current template for the current block in the current picture; and determine an initial reference template for the initial prediction block in the reference picture; and perform a motion vector refinement process to determine a modified prediction block based on a comparison of the current template to the initial reference template.

Template matching based affine prediction for video coding

Template matching based advanced motion vector predictor (AMVP) candidate list construction with non-adjacent candidates and AMVP index signaling

Systems and techniques are described herein for processing video data. For example, a process can include obtaining a video bitstream, the video bitstream including adaptive loop filter (ALF) data. The process can further include determining a value of an ALF chroma filter signal flag from the ALF data, the value of the ALF chroma filter signal flag indicating whether chroma ALF filter data is signaled in the video bitstream. The process can further include processing at least a portion of a slice of video data based on the value of the ALF chroma filter signal flag.

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San Diego, CA, United States of America

Yan Zhang