Picture prediction method and apparatus

1. A method comprising:

receiving a bitstream;

parsing the bitstream to obtain a combined intra and inter prediction mode identifier indicating whether a combined intra and inter prediction mode is applied for a current block;

determining that a geometric partitioning based prediction mode is not to be executed when the combined intra and inter prediction mode identifier indicates the combined intra and inter prediction mode is applied for the current block, wherein the geometric partitioning based prediction mode comprises a triangular prediction unit mode;

performing a motion compensation process according to a merge mode when the geometric partitioning based prediction mode is not executed to obtain an inter prediction sample;

obtaining an intra prediction sample according to an intra prediction mode in the combined intra and inter prediction mode, wherein the intra prediction mode is a planar mode when the combined intra and inter prediction mode identifier indicating the combined intra and inter prediction mode is applied for the current block; and

combining the inter prediction sample and the intra prediction sample to obtain prediction samples of the current block.

2. The method of claim 1 , wherein the method further comprises using inverse diagonal splitting in the triangular prediction unit mode according to a preset policy when the intra prediction mode in the combined intra and inter prediction mode is a DC mode or the planar mode.

3. The method of claim 1 , wherein the method further comprises:

avoiding parsing a triangular prediction unit mode identifier; and avoiding executing the triangular prediction unit mode according to a preset policy when the intra prediction mode in the combined intra and inter prediction mode is a DC mode or the planar mode.

4. The method of claim 1 , wherein the method further comprises:

avoiding parsing a triangular prediction unit mode identifier; and

avoiding executing the geometric partitioning based prediction mode when the combined intra and inter prediction mode is used.

5. The method of claim 2 , wherein the inverse diagonal splitting comprises splitting from a top-right corner to a bottom-left corner.

6. The method of claim 1 , further comprising:

performing the motion compensation process according to the geometric partitioning based prediction mode when the geometric partitioning based prediction mode is executed.

7. The method of claim 1 , further comprising:

parsing the bitstream to obtain a geometric partitioning based prediction mode index; and

obtaining a splitting direction of the geometric partitioning based prediction mode based on the geometric partitioning based prediction mode index when the geometric partitioning based prediction mode is to be executed.

8. The method of claim 1 , further comprising:

generating a merge motion information candidate list; and

determining motion information of the current block based on a merge index carried in the bitstream when the geometric partitioning based prediction mode is not to be executed, wherein the motion information is used to obtain the inter prediction sample of the current block.

9. The method of claim 1 , further comprising:

parsing the bitstream to obtain an intra encoding mode-related syntax; and

selecting the intra prediction mode from an intra candidate mode list based on the intra encoding mode-related syntax.

10. A method comprising:

obtaining a combined intra and inter prediction mode identifier indicating whether a combined intra and inter prediction mode is applied for a current block;

determining that a geometric partitioning based prediction mode is to be executed when a constraint condition is met, wherein the constraint condition comprises the combined intra and inter prediction mode identifier indicating the combined intra and inter prediction mode is not applied for the current block, and wherein the geometric partitioning based prediction mode comprises a triangular prediction unit mode;

determining motion information of the current block according to the geometric partitioning based prediction mode; and

performing a motion compensation process based on the motion information to obtain prediction samples of the current block.

11. The method of claim 10 , further comprising determining that the triangular prediction unit mode is to be executed based on a triangular prediction unit mode identifier (merge_triangle_flag).

12. The method of claim 10 , further comprising obtaining a splitting direction of the geometric partitioning based prediction mode.

13. The method of claim 10 , further comprising determining that the geometric partitioning based prediction mode is not to be executed for the current block when the combined intra and inter prediction mode identifier indicating the combined intra and inter prediction mode is applied for the current block.

14. An apparatus comprising:

a memory configured to store instructions; and

a processor coupled to the memory, wherein the instructions cause the processor to be configured to:

obtain a combined intra and inter prediction mode identifier indicating whether a combined intra and inter prediction mode is applied for a current block;

determine that a geometric partitioning based prediction mode is to be executed when a constraint condition is met wherein the constraint condition comprises the combined intra and inter prediction mode identifier indicating the combined intra and inter prediction mode is not applied for the current block;

determine motion information of the current block according to the geometric partitioning based prediction mode; and

perform a motion compensation process based on the motion information to obtain prediction samples of the current block.

15. The apparatus of claim 14 , wherein the instructions further cause the processor to be configured to determine that the geometric partitioning based prediction mode is not to be executed for the current block when the combined intra and inter prediction mode identifier indicating the combined intra and inter prediction mode is applied for the current block.

16. The apparatus of claim 14 , wherein the instructions further cause the processor to be configured to:

parse a bitstream to obtain a geometric partitioning based prediction mode index; and

obtain a splitting direction of the geometric partitioning based prediction mode based on the geometric partitioning based prediction mode index when the geometric partitioning based prediction mode is to be executed.

17. The apparatus of claim 14 , wherein when the combined intra and inter prediction mode identifier indicating the combined intra and inter prediction mode is applied for the current block, an intra prediction mode in the combined intra and inter prediction mode is a planar mode.

18. The apparatus of claim 14 , wherein when the combined intra and inter prediction mode identifier indicating the combined intra and inter prediction mode is applied for the current block, a motion compensation process according to a merge mode is performed to obtain an inter prediction sample of the current block.

19. The method of claim 10 , further comprising performing a motion compensation process according to a merge mode to obtain an inter prediction sample of the current block when the combined intra and inter prediction mode identifier indicating the combined intra and inter prediction mode is applied for the current block.

20. The method of claim 10 , wherein when the combined intra and inter prediction mode identifier indicating the combined intra and inter prediction mode is applied for the current block, an intra prediction mode in the combined intra and inter prediction mode is a planar mode.