HMVC for affine and SBTMVP motion vector prediction modes

1 . A method comprising:

decoding sub-blocks of a first block of a current picture, the sub-blocks being decoded based on first sub-block motion vectors determined according to first motion information data associated with the first block;

determining a second motion vector as a combination of at least two first sub-block motion vectors of sub-blocks selected from spatially distinct positions in the first block; and

adding the second motion vector to a History-based Motion Vector Prediction (HMVP) list of motion information data, items of the HMVP list being used to determine a motion information data for a second block of the current picture.

2 . An apparatus for decoding blocks of a current picture, the apparatus comprising a processor configured for:

decoding sub-blocks of a first block of a current picture, the sub-blocks being decoded based on first sub-block motion vectors determined according to first motion information data associated with the first block;

determining a second motion vector as a combination of at least two first sub-block motion vectors of sub-blocks selected from spatially distinct positions in the first block; and

adding the second motion vector to a History-based Motion Vector Prediction (HMVP) list of motion information data, items of the HMVP list being used to determine a motion information data for a second block of the current picture.

3 . A method comprising:

encoding sub-blocks of a first block of a current picture, the sub-blocks being encoded based on first sub-block motion vectors determined according to first motion information data associated with the first block;

determining a second motion vector as a combination of at least two first sub-block motion vectors of sub-blocks selected from spatially distinct positions in the first block; and

adding the second motion vector to a History-based Motion Vector Prediction (HMVP) list of motion information data, items of the HMVP list being used to determine a motion information data for a second block of the current picture.

4 . An apparatus for encoding blocks of a current picture, the apparatus comprising a processor configured for:

encoding sub-blocks of a first block of a current picture, the sub-blocks being encoded based on first sub-block motion vectors determined according to first motion information data associated with the first block;

determining a second motion vector as a combination of at least two first sub-block motion vectors of sub-blocks selected from spatially distinct positions in the first block; and

adding the second motion vector to a History-based Motion Vector Prediction (HMVP) list of motion information data, items of the HMVP list being used to determine a motion information data for a second block of the current picture.

5 . The method of claim 1 , wherein the combination of the at least two first sub-block motion vectors depends on a size of the first block or on a size of the sub-blocks.

6 . A device comprising:

the apparatus of claim 2 ; and

at least one of (i) an antenna configured to receive a signal, the signal including the decoded blocks of the current picture, (ii) a band limiter configured to limit the received signal to a band of frequencies that includes the decoded blocks of the current picture, or (iii) a display configured to display an output representative of the decoded blocks of the current picture.

7 . A non-transitory computer readable medium containing data content generated according to the method of claim 3 , for playback using a processor.

8 . The apparatus of claim 2 , wherein the combination of the at least two first sub-block motion vectors depends on a size of the first block or on a size of the sub-blocks.

9 . The method of claim 3 , wherein the combination of the at least two first sub-block motion vectors depends on a size of the first block or on a size of the sub-blocks.

10 . The apparatus of claim 4 , wherein the combination of the at least two first sub-block motion vectors depends on a size of the first block or on a size of the sub-blocks.

11 . A non-transitory computer-readable storage medium storing instructions that, when executed by a processor, cause the processor to perform the method of claim 1 .

12 . A non-transitory computer-readable storage medium storing instructions that, when executed by a processor, cause the processor to perform the method of claim 3 .

13 . The method of claim 1 , wherein the combination of at least two first sub-block motion vectors of sub-blocks selected from spatially distinct positions of the first block is an average of the at least two first sub-block motion vectors selected from spatially distinct positions of the first block.

14 . The method of claim 1 , wherein determining a second motion vector as a combination of at least two first sub-block motion vectors of sub-blocks selected from spatially distinct positions of the first block comprises determining the second motion vector by computing a weighted average of at least two first sub-block motion vectors selected from spatially distinct positions of the first block, wherein weights of the weighted average and/or the spatially distinct positions are determined as a function of a size of the first block.

15 . The apparatus of claim 2 , wherein the combination of at least two first sub-block motion vectors of sub-blocks selected from spatially distinct positions of the first block is an average of the at least two first sub-block motion vectors selected from spatially distinct positions of the first block.

16 . The apparatus of claim 2 , wherein determining a second motion vector as a combination of at least two first sub-block motion vectors of sub-blocks selected from spatially distinct positions of the first block comprises determining the second motion vector by computing a weighted average of at least two first sub-block motion vectors selected from spatially distinct positions of the first block, wherein weights of the weighted average and/or the spatially distinct positions are determined as a function of a size of the first block.

17 . The method of claim 3 , wherein the combination of at least two first sub-block motion vectors of sub-blocks selected from spatially distinct positions of the first block is an average of the at least two first sub-block motion vectors selected from spatially distinct positions of the first block.

18 . The method of claim 3 , wherein determining a second motion vector as a combination of at least two first sub-block motion vectors of sub-blocks selected from spatially distinct positions of the first block comprises determining the second motion vector by computing a weighted average of at least two first sub-block motion vectors selected from spatially distinct positions of the first block, wherein weights of the weighted average and/or the spatially distinct positions are determined as a function of a size of the first block.

19 . The apparatus of claim 4 , wherein the combination of at least two first sub-block motion vectors of sub-blocks selected from spatially distinct positions of the first block is an average of the at least two first sub-block motion vectors selected from spatially distinct positions of the first block.

20 . The apparatus of claim 4 , wherein determining a second motion vector as a combination of at least two first sub-block motion vectors of sub-blocks selected from spatially distinct positions of the first block comprises determining the second motion vector by computing a weighted average of at least two first sub-block motion vectors selected from spatially distinct positions of the first block, wherein weights of the weighted average and/or the spatially distinct positions are determined as a function of a size of the first block.