US 12,137,243 B2
Method for refining a motion vector derived under a merge mode using a difference vector
Bae Keun Lee, Gyeonggi-do (KR)
Assigned to KT CORPORATION, Gyeonggi-do (KR)
Filed by KT CORPORATION, Gyeonggi-do (KR)
Filed on Aug. 23, 2022, as Appl. No. 17/893,421.
Application 17/893,421 is a continuation of application No. 16/619,231, granted, now 11,457,235, previously published as PCT/KR2018/009869, filed on Aug. 27, 2018.
Claims priority of application No. 10-2017-0109639 (KR), filed on Aug. 29, 2017.
Prior Publication US 2022/0417554 A1, Dec. 29, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. H04N 19/577 (2014.01); H04N 19/159 (2014.01); H04N 19/176 (2014.01); H04N 19/52 (2014.01); H04N 19/56 (2014.01)
CPC H04N 19/577 (2014.11) [H04N 19/159 (2014.11); H04N 19/176 (2014.11); H04N 19/52 (2014.11); H04N 19/56 (2014.11)] 5 Claims
OG exemplary drawing
 
1. A method of decoding a video, the method comprising:
obtaining a motion vector of a current block based on one of a plurality of inter modes pre-defined in a decoding apparatus, the inter modes including a motion vector prediction mode and a merge mode; and
performing inter prediction on the current block based on the motion vector,
wherein, under the motion vector prediction mode, the motion vector of the current block is obtained by adding a motion vector difference to one of a plurality of motion vector predictors,
wherein, under the merge mode, obtaining the motion vector of the current block comprises:
obtaining an initial motion vector of the current block based on a merge candidate selected from a plurality of merge candidates;
determining whether to refine the initial motion vector of the current block or not;
when it is determined to refine the initial motion vector, obtaining a difference vector for refining the initial motion vector of the current block; and
obtaining a refined motion vector of the current block by adding the difference vector to the initial motion vector,
wherein the merge candidate is selected from the plurality of merge candidates based on first index information parsed from a bitstream, the first index information indicating an index of the merge candidate,
wherein the difference vector is determined based on a difference value candidate selected from a plurality of difference value candidates,
wherein the difference value candidate is selected, from the plurality of difference value candidates, based on second index information parsed from the bitstream, the second index information indicating an index of the difference value candidate,
wherein the plurality of difference value candidates are pre-defined in the decoding apparatus, and
wherein refining the initial motion vector based on the difference value candidate is allowed only for the merge mode, but is not allowed for the motion vector prediction mode.