公开(公告)号：US12015762B2

公开(公告)日：2024-06-18

申请号：US17466129

申请日：2021-09-03

Applicant: HUAWEI TECHNOLOGIES CO., LTD.

Inventor： Sriram Sethuraman ,  Semih Esenlik ,  Jeeva Raj A ,  Sagar Kotecha

IPC: H04N19/105 ,  H04N19/132 ,  H04N19/137 ,  H04N19/159 ,  H04N19/176 ,  H04N19/46

CPC classification number: H04N19/105 ,  H04N19/132 ,  H04N19/137 ,  H04N19/159 ,  H04N19/176 ,  H04N19/46

Abstract: The present disclosure provides an inter prediction method, comprising the steps of obtaining an initial motion vector and a reference picture for bi-prediction; obtaining sets of candidate sample positions in the reference picture according to the initial motion vector and candidate motion vectors, wherein each candidate motion vector is derived by the initial motion vector and a respective motion vector offset, and wherein each set of candidate sample positions corresponds to each candidate motion vector; obtaining a respective set of sample positions from each set of candidate sample positions; computing a matching cost for each candidate motion vector within each set of sample positions; obtaining a refined motion vector based on the computed matching cost of each candidate motion vector; and obtaining prediction values for a current block based on the refined motion vector.

公开(公告)号：US11968387B2

公开(公告)日：2024-04-23

申请号：US17467785

申请日：2021-09-07

Applicant: HUAWEI TECHNOLOGIES CO., LTD.

Inventor： Sriram Sethuraman ,  Sagar Kotecha ,  Jeeva Raj A

IPC: H04N19/513 ,  H04N19/107 ,  H04N19/132 ,  H04N19/139 ,  H04N19/176

CPC classification number: H04N19/513 ,  H04N19/107 ,  H04N19/132 ,  H04N19/139 ,  H04N19/176

Abstract: A bidirectional optical flowing prediction method includes obtaining an initial motion vector pair for a current block, obtaining a forward and a backward prediction block according to the forward motion vector and a backward prediction block according to the initial motion vector pair, and calculating gradient parameters for a current sample in the current block. The method further includes obtaining at least two sample optical flow parameters, including a first parameter and a second parameter, for the current sample based on the gradient parameters, obtaining block optical flow parameters based on sample optical flow parameters of samples in the current block, and obtaining a prediction value of the current block. One of the block optical flow parameters is obtained by multiplying the first parameter and a sign function of the second parameter, and the sign function is a piecewise function with at least three subintervals.

公开(公告)号：US11889109B2

公开(公告)日：2024-01-30

申请号：US17478184

申请日：2021-09-17

Applicant: HUAWEI TECHNOLOGIES CO., LTD.

Inventor： Sriram Sethuraman ,  Jeeva Raj A ,  Sagar Kotecha

IPC: H04N19/577 ,  H04N19/132 ,  H04N19/172 ,  H04N19/176

CPC classification number: H04N19/577 ,  H04N19/132 ,  H04N19/172 ,  H04N19/176

Abstract: In some embodiments, a video encoder or a video decoder obtains a pair of motion vectors for a current coding block of a video signal with respect to two reference frames. Predictions of the current block are generated using the pair of motion vectors from respective reference frames. The video encoder or video decoder further determine an optical flow for the current coding block based on samples values in the predictions. One component of the optical flow is determined based on the other component of the optical flow. Bi-predictive optical flow (BPOF) can be performed on the current coding block using the determined optical flow.

公开(公告)号：US20240007666A1

公开(公告)日：2024-01-04

申请号：US18346795

申请日：2023-07-04

Applicant: HUAWEI TECHNOLOGIES CO., LTD.

Inventor： Sriram Sethuraman ,  Jeeva Raj A

IPC: H04N19/557 ,  H04N19/513 ,  H04N19/53 ,  H04N19/573 ,  G06T3/40

CPC classification number: H04N19/557 ,  H04N19/521 ,  H04N19/53 ,  H04N19/573 ,  G06T3/4007

Abstract: Methods and apparatuses of determining an alignment level between motion compensated reference patches for reducing motion vector refinement steps are provided. According to one method, obtaining, by a decoder, motion compensated interpolated samples based on sub-pixel accurate merge motion vectors from a bilinear motion compensated interpolation; computing, by the decoder, a sum of absolute differences (SAD) between two motion compensated reference patches using a subset of the motion compensated interpolated samples; determining, by the decoder, whether the SAD is less than a coding unit (CU) size-dependent threshold value; when the SAD is less than the CU size-dependent threshold value: skipping remaining decoder-side motion vector refinement (DMVR) process steps; and performing final motion compensation; and when the SAD is not less than the CU size-dependent threshold value: performing the remaining DMVR process steps; and performing the final motion compensation.

公开(公告)号：US11722691B2

公开(公告)日：2023-08-08

申请号：US17394598

申请日：2021-08-05

Applicant: HUAWEI TECHNOLOGIES CO., LTD.

Inventor： Sriram Sethuraman ,  Jeeva Raj A

IPC: H04N19/557 ,  H04N19/513 ,  H04N19/53 ,  H04N19/573 ,  G06T3/40

CPC classification number: H04N19/557 ,  G06T3/4007 ,  H04N19/521 ,  H04N19/53 ,  H04N19/573

Abstract: Methods and apparatuses of determining an alignment level between motion compensated reference patches for reducing motion vector refinement steps are provided. According to one method, obtaining, by a decoder, motion compensated interpolated samples based on sub-pixel accurate merge motion vectors from a bilinear motion compensated interpolation; computing, by the decoder, a sum of absolute differences (SAD) between two motion compensated reference patches using a subset of the motion compensated interpolated samples; determining, by the decoder, whether the SAD is less than a coding unit (CU) size-dependent threshold value; when the SAD is less than the CU size-dependent threshold value: skipping remaining decoder-side motion vector refinement (DMVR) process steps; and performing final motion compensation; and when the SAD is not less than the CU size-dependent threshold value: performing the remaining DMVR process steps; and performing the final motion compensation.

公开(公告)号：US11563948B2

公开(公告)日：2023-01-24

申请号：US17249771

申请日：2021-03-12

Applicant: HUAWEI TECHNOLOGIES CO., LTD.

Inventor： Sriram Sethuraman ,  Jeeva Raj A ,  Sagar Kotecha

IPC: H04N19/137 ,  H04N19/105 ,  H04N19/159 ,  H04N19/176 ,  H04N19/52 ,  H04N19/70

Abstract: A method for inter-prediction of a current image block in a current picture of a video is provided. The method includes determining whether a first temporal distance (such as TD0) is equal to a second temporal distance (such as TD1), wherein the first temporal distance is represented in terms of a difference between a picture order count value of the current picture and a picture order count value of a first reference picture; and the second temporal distance is represented in terms of a difference between a picture order count value of a second reference picture and the picture order count value of the current picture; and performing no motion vector refinement (DMVR) procedure when it is determined that the first temporal distance (TD0) is not equal to the second temporal distance (TD1). Thus the DMVR procedure is restricted to only the image block with equal-distance references.

公开(公告)号：US11490096B2

公开(公告)日：2022-11-01

申请号：US17308311

申请日：2021-05-05

Applicant: HUAWEI TECHNOLOGIES CO., LTD.

Inventor： Sriram Sethuraman ,  Jeeva Raj A ,  Sagar Kotecha

IPC: H04N19/159 ,  H04N19/105 ,  H04N19/132 ,  H04N19/176 ,  H04N19/513

Abstract: Methods and system, including decoders and encoders, for interprediction. In one aspect, a method includes selecting reference samples based on motion information of a current picture block of a current picture, deriving first interpolated samples by performing a first interpolation on the selected reference samples, deriving an integer distance delta motion vector for a target sub-prediction unit (PU) by performing integer-distance MVR, deriving M×M pixel matrix flow vectors by performing BPOF, for each M×M pixel matrix in the target sub-PU, based on the first interpolated samples and the integer distance delta motion vector, deriving second interpolated samples by performing a second interpolation on the reference samples, computing at least one correction parameter for the target sub-PU based on the M×M pixel matrix flow vectors, the first interpolated samples and the second interpolated samples, and performing bi-prediction based on the second interpolated samples and the at least one correction parameter.

公开(公告)号：US20220060690A1

公开(公告)日：2022-02-24

申请号：US17466930

申请日：2021-09-03

Applicant: Huawei Technologies Co., Ltd.

Inventor： Sriram SETHURAMAN ,  Sagar KOTECHA ,  Jeeva Raj A

IPC: H04N19/105 ,  H04N19/137 ,  H04N19/132 ,  H04N19/159 ,  H04N19/176

Abstract: A method for inter prediction of a block of a picture and corresponding apparatus are provided. The method comprises: determining a first prediction block based on an initial first motion vector of a current block in a first reference picture, so as to obtain a first extension block; obtaining from the first reference picture, one or more first reference blocks each of which is associated with a combination of the initial first motion vector and one of motion vector offsets; obtaining a target motion vector offset with a smallest cost among the motion vector offsets; determining for the current block, a refined first motion vector which is a combination of the initial first motion vector and the target motion vector offset; and obtaining a refined prediction block of the current block based on the refined first motion vector, thereby improving coherence of refined motion vectors to achieve higher coding efficiencies.

公开(公告)号：US20210400259A1

公开(公告)日：2021-12-23

申请号：US17466129

申请日：2021-09-03

Applicant: HUAWEI TECHNOLOGIES CO., LTD.

Inventor： Sriram SETHURAMAN ,  Semih ESENLIK ,  Jeeva Raj A ,  Sagar KOTECHA

IPC: H04N19/105 ,  H04N19/132 ,  H04N19/137 ,  H04N19/159 ,  H04N19/46 ,  H04N19/176

Abstract: The present disclosure provides an inter prediction method, comprising the steps of obtaining an initial motion vector and a reference picture for bi-prediction; obtaining sets of candidate sample positions in the reference picture according to the initial motion vector and candidate motion vectors, wherein each candidate motion vector is derived by the initial motion vector and a respective motion vector offset, and wherein each set of candidate sample positions corresponds to each candidate motion vector; obtaining a respective set of sample positions from each set of candidate sample positions; computing a matching cost for each candidate motion vector within each set of sample positions; obtaining a refined motion vector based on the computed matching cost of each candidate motion vector; and obtaining prediction values for a current block based on the refined motion vector.