Picture prediction method and apparatus, and computer-readable storage medium
A picture prediction method includes: determining whether a merge mode is used for a current picture block; when the merge mode is used for the current picture block, determining whether a regular merge mode is available; when the regular merge mode is unavailable, and a high-layer syntax element sps_triangle_enabled_flag corresponding to a triangle partition mode (TPM), indicates that the TPM is forbidden to be used, determining a combined intra and inter prediction (CIIP) mode as a target merge mode used for the current picture block and predicting the current picture block based on the target merge mode.
1. A method of picture prediction, comprising:
determining whether a merge mode is used for a current picture block;
when the merge mode is used for the current picture block, determining whether a level-1 merge mode is available;
when the level-1 merge mode is unavailable, determining a target merge mode from a level-2 merge mode, wherein the level-2 merge mode comprises a triangle partition mode (TPM) mode and a combined intra and inter prediction (CIIP) mode; and
when the CIIP mode is allowed to be used, and any one of conditions 1-5 is not met, determining the CIIP mode as the target merge mode;
wherein
the condition 1: the TPM mode is allowed to be used;
the condition 2: a type of a slice or slice group in which the current picture block is located is bi-directional;
the condition 3: a maximum quantity of candidate TPM modes supported by the slice or the slice group in which the current picture block is located is determined to be greater than or equal to 2;
the condition 4: a size of the current picture block meets a preset condition; and
the condition 5: a skip mode is not used to predict the current picture block.
2. The method according to claim 1 , wherein determining the target merge mode from the level-2 merge mode comprises:
when any one of the conditions 1-5 is not met, setting a value of available status information that indicates an available status of the CIIP mode to a first value, wherein when the value of the available status information that indicates the available status of the CIIP mode is the first value, the CIIP mode is used to perform picture prediction on the current picture block.
3. The method according to claim 1 , wherein determining the target merge mode from the level-2 merge mode comprises:
when all of the conditions 1-5 are met, determining the target merge mode based on at least one of a high-layer syntax element corresponding to the CIIP mode or available status information that indicates an available status of the CIIP mode, wherein the available status information that indicates the available status of the CIIP mode indicates whether the CIIP mode is used when the current picture block is predicted.
4. The method according to claim 3 , wherein determining the target merge mode based on the at least one of the high-layer syntax element corresponding to the CIIP mode or the available status information that indicates the available status of the CIIP mode comprises:
when the high-layer syntax element corresponding to the at least one of the CIIP mode or the available status information that indicates the available status of the CIIP mode indicates that the CIIP mode is forbidden to be used, determining the TPM mode as the target merge mode.
5. The method according to claim 4 , wherein determining the TPM mode as the target merge mode comprises:
setting a value of available status information that indicates an available status of the TPM mode to a first value, wherein when the value of the available status information that indicates the available status of the TPM mode is the first value, the TPM mode is used to perform picture prediction on the current picture block.
6. The method according to claim 1 , wherein the method is performed by an encoder to encode the current picture block.
7. The method according to claim 1 , wherein the method is performed by a decoder to decode the current picture block.
8. An apparatus, comprising:
one or more processors; and
a memory configured to store a program, which when executed by the one or more processors, cause the one or more processors perform operations, the operations comprising:
determining whether a merge mode is used for a current picture block;
when the merge mode is used for the current picture block, determining whether a level-1 merge mode is available;
when the level-1 merge mode is unavailable, determining a target merge mode from a level-2 merge mode, wherein the level-2 merge mode comprises a triangle partition mode (TPM) mode and a combined intra and inter prediction (CIIP) mode; and
when the CIIP mode is allowed to be used, and any one of conditions 1-5 is not met, determining the CIIP mode as the target merge mode;
wherein
the condition 1: the TPM mode is allowed to be used;
the condition 2: a type of a slice or slice group in which the current picture block is located is bi-directional;
the condition 3: a maximum quantity of candidate TPM modes supported by the slice or the slice group in which the current picture block is located is determined to be greater than or equal to 2;
the condition 4: a size of the current picture block meets a preset condition; and
the condition 5: a skip mode is not used to predict the current picture block.
9. The apparatus according to claim 8 , wherein determining the target merge mode from the level-2 merge mode comprises:
when any one of the conditions 1-5 is not met, setting a value of available status information that indicates an available status of the CIIP mode to a first value, wherein when the value of the available status information that indicates the available status of the CIIP mode is the first value, the CIIP mode is used to perform picture prediction on the current picture block.
10. The apparatus according to claim 8 , wherein determining the target merge mode from the level-2 merge mode comprises:
when all of the conditions 1-5 are met, determining the target merge mode based on at least one of a high-layer syntax element corresponding to the CIIP mode or available status information that indicates an available status of the CIIP mode, wherein the available status information that indicates the available status of the CIIP mode indicates whether the CIIP mode is used when the current picture block is predicted.
11. The apparatus according to claim 10 , wherein determining the target merge mode based on the at least one of the high-layer syntax element corresponding to the CIIP mode or the available status information that indicates the available status of the CIIP mode comprises:
when the high-layer syntax element corresponding to the at least one of the CIIP mode or the available status information that indicates the available status of the CIIP mode indicates that the CIIP mode is forbidden to be used, determining the TPM mode as the target merge mode.
12. The apparatus according to claim 10 , wherein determining the TPM mode as the target merge mode comprises:
setting a value of available status information that indicates an available status of the TPM mode to a first value, wherein when the value of the available status information that indicates the available status of the TPM mode is the first value, the TPM mode is used to perform picture prediction on the current picture block.
13. The apparatus according to claim 8 , wherein the apparatus is implemented as part of an encoder to encode the current picture block.
14. The apparatus according to claim 8 , wherein the apparatus is implemented as part of a decoder to decode the current picture block.
15. A non-transitory computer-readable medium storing computer instructions, that when executed by one or more processor, cause the one or more processor to perform operations, the operations comprising:
determining whether a merge mode is used for a current picture block;
when the merge mode is used for the current picture block, determining whether a level-1 merge mode is available;
when the level-1 merge mode is unavailable, determining a target merge mode from a level-2 merge mode, wherein the level-2 merge mode comprises a triangle partition mode (TPM) mode and a combined intra and inter prediction (CIIP) mode; and
when the CIIP mode is allowed to be used, and any one of conditions 1-5 is not met, determining the CIIP mode as the target merge mode;
wherein
the condition 1: the TPM mode is allowed to be used;
the condition 2: a type of a slice or slice group in which the current picture block is located is bi-directional;
the condition 3: a maximum quantity of candidate TPM modes supported by the slice or the slice group in which the current picture block is located is determined to be greater than or equal to 2;
the condition 4: a size of the current picture block meets a preset condition; and
the condition 5: a skip mode is not used to predict the current picture block.
16. The non-transitory computer-readable medium according to claim 15 , wherein determining the target merge mode from the level-2 merge mode comprises:
when any one of the conditions 1-5 is not met, setting a value of available status information that indicates an available status of the CIIP mode to a first value, wherein when the value of the available status information that indicates the available status of the CIIP mode is the first value, the CIIP mode is used to perform picture prediction on the current picture block.
17. The non-transitory computer-readable medium according to claim 15 , wherein determining the target merge mode from the level-2 merge mode comprises:
when all of the conditions 1-5 are met, determining the target merge mode based on at least one of a high-layer syntax element corresponding to the CIIP mode or available status information that indicates an available status of the CIIP mode, wherein the available status information that indicates the available status of the CIIP mode indicates whether the CIIP mode is used when the current picture block is predicted.
18. The non-transitory computer-readable medium according to claim 17 , wherein determining the target merge mode based on the at least one of the high-layer syntax element corresponding to the CIIP mode or the available status information that indicates the available status of the CIIP mode comprises:
when the high-layer syntax element corresponding to the at least one of the CIIP mode or the available status information that indicates the available status of the CIIP mode indicates that the CIIP mode is forbidden to be used, determining the TPM mode as the target merge mode.
19. The non-transitory computer-readable medium according to claim 18 , wherein determining the TPM mode as the target merge mode comprises:
setting a value of available status information that indicates an available status of the TPM mode to a first value, wherein when the value of the available status information that indicates the available status of the TPM mode is the first value, the TPM mode is used to perform picture prediction on the current picture block.
20. The non-transitory computer-readable medium according to claim 15 , wherein the non-transitory computer-readable medium is in an encoder, to encode the current picture block.
21. The non-transitory computer-readable medium according to claim 15 , wherein the non-transitory computer-readable medium is in a decoder, to decode the current picture block.