Video picture prediction method and apparatus

1. A video picture prediction method, comprising:

parsing, from a sequence parameter set (SPS) in a bitstream, a value of a first indicator and a value of a third indicator;

if the value of the first indicator is equal to a first value,

parsing a value of a second indicator from the SPS, and

determining a maximum length of a first candidate motion vector list according to following formula:

MaxNumSubblockMergeCand= K−K _minus_max_num_subblock_merge_cand,

wherein MaxNumSubblockMergeCand represents the maximum length of the first candidate motion vector list, K_minus_max_num_subblock_merge_cand represents the second indicator, and K is a preset non-negative integer, wherein the first candidate motion vector list is constructed for a block to be processed when a subblock merge prediction mode is used for the block; and

if the value of the first indicator is equal to a second value, determining the maximum length of the first candidate motion vector list based on the value of the third indicator, the second value is different from the first value.

2. The method of claim 1 , wherein the determining a maximum length of a first candidate motion vector list based on the value of the third indicator comprises:

determining the maximum length of the first candidate motion vector list is 0, if the value of the third indicator is 0.

3. The method of claim 1 , wherein the determining a maximum length of a first candidate motion vector list based on the value of the third indicator comprises:

determining the maximum length of the first candidate motion vector list is 1, if the value of the third indicator is 1.

4. The method of claim 3 , wherein the value of the third indicator being 1 indicates that an advanced temporal motion vector prediction mode is present in the subblock merge prediction mode.

5. The method of claim 2 , wherein the value of the third indicator being 0 indicates that an advanced temporal motion vector prediction mode is not present in the subblock merge prediction mode.

6. The method of claim 4 , wherein the advanced temporal motion vector prediction mode is a prediction mode based on temporal motion vector of subblock.

7. The method of claim 1 , wherein the value of the first indicator indicates whether a candidate mode used to inter predict the block comprises an affine mode.

8. The method of claim 1 , wherein the first value is 1, the second value is 0.

9. A video picture prediction apparatus, comprising:

a parsing unit, configured to

parse, from a sequence parameter set (SPS) in a bitstream, a value of a first indicator and a value of a third indicator, and

parse a value of a second indicator from the SPS, if the value of the first indicator is equal to a first value; and

a determining unit, configured to

if the value of the first indicator is equal to the first value, determine a maximum length of a first candidate motion vector list according to following formula:

MaxNumSubblockMergeCand= K−K _minus_max_num_subblock_merge_cand,

wherein MaxNumSubblockMergeCand represents the maximum length of the first candidate motion vector list, K_minus_max_num_subblock_merge_cand represents the second indicator, and K is a preset non-negative integer, wherein the first candidate motion vector list is constructed for a block to be processed when a subblock merge prediction mode is used for the block, and

determine the maximum length of the first candidate motion vector list based on the value of the third indicator if the value of the first indicator is equal to a second value, wherein the second value is different from the first value.

10. The apparatus of claim 9 , wherein the determining a maximum length of a first candidate motion vector list based on the value of the third indicator comprises:

determining the maximum length of the first candidate motion vector list is 0, if the value of the third indicator is 0.

11. The apparatus of claim 9 , wherein the determining a maximum length of a first candidate motion vector list based on the value of the third indicator comprises:

determining the maximum length of the first candidate motion vector list is 1, if the value of the third indicator is 1.

12. The apparatus of claim 11 , wherein the value of the third indicator being 1 indicates that an advanced temporal motion vector prediction mode is present in the subblock merge prediction mode.

13. The apparatus of claim 10 , wherein the value of the third indicator being 0 indicates that an advanced temporal motion vector prediction mode is not present in the subblock merge prediction mode.

14. The apparatus of claim 12 , wherein the advanced temporal motion vector prediction mode is a prediction mode based on temporal motion vector of subblock.

15. The apparatus of claim 9 , wherein the value of the first indicator indicates whether a candidate mode used to inter predict the block comprises an affine mode.

16. The apparatus of claim 9 , wherein the first value is 1, the second value is 0.

17. A computer program product comprising program code for performing the method according to claim 1 when executed on a computer or a processor.

18. A video decoder, the decoder comprises:

one or more processors; and

a non-transitory computer-readable storage medium coupled to the processors and storing programming for execution by the processors, wherein the programming, when executed by the processors, configures the decoder to carry out the method according claim 1 .

19. A video data decoding device, comprising:

a non-transitory memory storage, configured to store video data in a form of a bitstream; and

a video decoder, configured to perform the method according to the claim 1 .