公开(公告)号：US20220007051A1

公开(公告)日：2022-01-06

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 ,  H04N19/176 ,  H04N19/132 ,  H04N19/172

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：US20210392334A1

公开(公告)日：2021-12-16

申请号：US17407617

申请日：2021-08-20

Applicant: HUAWEI TECHNOLOGIES CO., LTD.

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

IPC: H04N19/132 ,  H04N19/117 ,  H04N19/82 ,  H04N19/159 ,  H04N19/176

Abstract: It is provided a method of video coding implemented in a decoding device or an encoding device, the method comprising: obtaining initial motion vectors for a current block; obtaining first predictions for a sample value in the current block based on the initial motion vectors; calculating a first matching cost according to the first predictions; determining whether an optical flow refinement process should be performed or not, according to at least one preset condition, the at least one preset condition comprising a condition of whether the calculated first matching cost is equal to or larger than a threshold value; and performing an optical flow refinement process for obtaining a final inter prediction for the sample value in the current block, when it is determined that the optical flow refinement process should be performed.

公开(公告)号：US20250088637A1

公开(公告)日：2025-03-13

申请号：US18954675

申请日：2024-11-21

Applicant: HUAWEI TECHNOLOGIES CO., LTD.

Inventor： Sriram SETHURAMAN ,  Jeeva Raj A ,  Sagar KOTECHA

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

Abstract: A method for bi-directional optical flow prediction based on reference sample values from sample positions belonging to an extended region of a predicted block used in the bi-directional optical flow prediction of a current block is provided, wherein sub-pixel positions in the extended region of the predicted block in the reference picture are rounded to obtain integer pixel sample positions in the reference picture, wherein the reference sample values at the obtained integer pixel sample positions in the reference picture are used in the computation of boundary sample gradients corresponding to the boundaries of the predicted block in the reference picture.

公开(公告)号：US20240283938A1

公开(公告)日：2024-08-22

申请号：US18592849

申请日：2024-03-01

Applicant: HUAWEI TECHNOLOGIES CO., LTD.

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

IPC: H04N19/132 ,  H04N19/117 ,  H04N19/159 ,  H04N19/176 ,  H04N19/82

CPC classification number: H04N19/132 ,  H04N19/117 ,  H04N19/159 ,  H04N19/176 ,  H04N19/82

Abstract: It is provided a method of video coding implemented in a decoding device or an encoding device, the method comprising: obtaining initial motion vectors for a current block; obtaining first predictions for a sample value in the current block based on the initial motion vectors; calculating a first matching cost according to the first predictions; determining whether an optical flow refinement process should be performed or not, according to at least one preset condition, the at least one preset condition comprising a condition of whether the calculated first matching cost is equal to or larger than a threshold value; and performing an optical flow refinement process for obtaining a final inter prediction for the sample value in the current block, when it is determined that the optical flow refinement process should be performed.

公开(公告)号：US20240244255A1

公开(公告)日：2024-07-18

申请号：US18423846

申请日：2024-01-26

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：US20220116648A1

公开(公告)日：2022-04-14

申请号：US17556594

申请日：2021-12-20

Applicant: HUAWEI TECHNOLOGIES CO., LTD.

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

IPC: H04N19/52 ,  H04N19/172 ,  H04N19/577 ,  H04N19/70 ,  H04N19/174 ,  H04N19/176

Abstract: It is provided a method of decoding a video bitstream implemented by a decoding device, the video bitstream including coded data for a plurality of pictures. The decoding method comprises: parsing an enabling flag for decoder motion vector refinement (DMVR) from a sequence parameter set of the video bitstream; parsing a disabling flag for DMVR from a syntax structure of a lower hierarchic syntax structure level than the sequence parameter set (SPS) level of the video bitstream; and performing DMVR based inter bi-prediction for a current block within at least one region of the current picture to obtain predicted sample values of the current block when at least one pre-defined condition is fulfilled, and wherein the at least one pre-defined condition comprises that the parsed value of the disabling flag specifies that DMVR based inter bi-prediction is enabled for at least one region of the current picture.

公开(公告)号：US20210409754A1

公开(公告)日：2021-12-30

申请号：US17467794

申请日：2021-09-07

Applicant: HUAWEI TECHNOLOGIES CO., LTD.

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

IPC: H04N19/52 ,  H04N19/533 ,  H04N19/57 ,  H04N19/176 ,  H04N19/567 ,  H04N19/172 ,  H04N19/105 ,  H04N19/56

Abstract: A method for determining a motion vector to be used in inter-prediction of a current block of a video picture, the method comprising: obtaining an initial motion vector; obtaining at least two groups of points according to the initial motion vector, wherein a first group of the at least two groups of points only includes a first point corresponding to the initial motion vector and additional N points with N≥0 and wherein each point of the first group is closer to the first point than any point of the points of a second group of the at least two groups; and obtaining the motion vector for the current block according to the at least two groups of points and a cost function.