Qualcomm Incorporated

Zhi Zhang

Marta Karczewicz

Vadim Seregin

Han Huang

Chun-Chi Chen

Yan Zhang

Yao-Jen Chang

Wei-Jung Chien

Cheng-Teh Hsieh

Pavel Nikitin

A method of decoding video data includes determining a vector predictor for a current block; determining a first set of vector difference candidates based on a first pel-interval, the first pel-interval defining a first distance between consecutive vector difference candidates in the first set of vector difference candidates starting with the vector predictor; determining a second set of vector difference candidates based on the first set of vector difference candidates and a second pel-interval, the second pel-interval defining a second distance between consecutive vector difference candidates in the second set of vector difference candidates; constructing a vector difference candidate list based on the second set of vector difference candidates; determining a vector for the current block based on the vector predictor and a vector difference from the vector difference candidate list; and reconstructing the current block based on the vector for the current block.

Vector difference candidate list construction

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

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

A video decoder may be configured to determine a motion vector and a motion vector precision for a current block; identify a current block template within the current picture; search within a search area for a final reference block template that corresponds to the current block template, wherein to search within the search area, the one or more processors are further configured to: identify an initial reference block template based on the motion vector, search other reference block templates around the initial reference block template using a step size that is set to an initial step size, and iteratively reduce the step size from the initial step size until the step size is set to a final step size that equals the motion vector precision; determine a prediction block for the current block based on the final reference block template.

Template matching in video coding

A video decoder can be configured to determine that a current block of the video data is coded in a bi-prediction inter mode; receive a first syntax element identifying a motion vector predictor from a first candidate list of motion vector predictors; receive a second syntax element identifying a motion vector difference; determine a first motion vector for the current block based on the motion vector predictor and the motion vector difference; determine a second motion vector for the current block from a second list of candidate motion vector predictors based on bilateral matching; and determine a prediction block for the current block using the first motion vector and the second motion vector.

Hybrid inter bi-prediction in video coding

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

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

Systems and techniques are provided for processing video data. For example, the systems and techniques can include obtaining a current picture of video data and obtaining reference pictures for the current picture from the video data. A merge mode candidate can be determined for the current picture. First and second motion vectors can be identified for the merge mode candidate. A motion vector search strategy can be selected for the merge mode candidate from a plurality of motion vector search strategies. The selected motion vector search strategy can be associated with one or more constraints corresponding to at least one of the first motion vector or the second motion vector. The selected motion vector search strategy can be used to determine refined motion vectors based on the first motion vector, the second motion vector, and the reference pictures. The merge mode candidate can be processed using the refined motion vectors.

Adaptive bilateral matching for decoder side motion vector refinement

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

A method of decoding video data may comprise decoding data from an encoded bitstream to generate motion vectors and performing a decoder-side motion vector refinement (DMVR) process on one or more of the motion vectors. Performing the DMVR process may include determining one or more characteristics of current video block being decoded and determining a search area for the DMVR process for the current video block based on the determined one or more characteristics of the current video block.

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Munich, Germany

Zhi Zhang