Motion compensation method and device, and computer system
A motion compensation method includes determining one or more weighting coefficients of a predicted value of a target pixel to be processed according to at least one of a first parameter or a second parameter, and determining the predicted value of the target pixel according to the weighting coefficient. The target pixel is in a boundary pixel block of a current image block. The first parameter is a size of the current image block or a distance between the target pixel and a center position of the current image block. The second parameter is a size of an adjacent image block of the current image block or a distance between the target pixel and a center position of the adjacent image block.
1. A motion compensation method comprising:
determining one or more weighting coefficients of a predicted value of a target pixel to be processed according to at least one of a first parameter or a second parameter, the one or more weighting coefficients including a first coefficient and a second coefficient, and determining the one or more weighting coefficients including:
determining the first coefficient based on the first parameter according to a preset negative mapping relationship that the first coefficient decreases as the first parameter increases; or
determining the second coefficient based on the first parameter according to a preset positive mapping relationship that the second coefficient increases as the first parameter increases;
determining the predicted value of the target pixel according to the weighting coefficient including:
determining a first predicted value of the target pixel according to a motion vector of a current image block;
determining a second predicted value of the target pixel according to a motion vector of an adjacent image block; and
obtaining the predicted value of the target pixel as a weighted sum of the first predicted value weighted by the first coefficient and the second predicted value weighted by the second coefficient;
wherein:
the target pixel is in a boundary pixel block of the current image block;
the first parameter is a size of the current image block or a distance between the target pixel and a center position of the current image block; and
the second parameter is a size of the adjacent image block of the current image block or a distance between the target pixel and a center position of the adjacent image block.
2. The method of claim 1 , wherein determining the one or more weighting coefficients of the predicted value of the target pixel further includes:
in response to the first parameter being between a first threshold and a second threshold, determining the first coefficient as a first preset value and/or the second coefficient as a second preset value, the first threshold being greater than the second threshold;
in response to the first parameter being greater than the first threshold, determining the first coefficient as a third preset value and/or the second coefficient as a fourth preset value, the third preset value being smaller than the first preset value, and the fourth preset value being greater than the second preset value; or
in response to the first parameter being smaller than the second threshold, determining the first coefficient as a fifth preset value and/or the second coefficient as a sixth preset value, the fifth preset value being greater than the first preset value, and the sixth preset value being smaller than the second preset value.
3. The method of claim 1 , wherein determining the one or more weighting coefficients of the predicted value of the target pixel further includes:
determining the first coefficient based on the second parameter according to a preset positive mapping relationship that the first coefficient increases as the second parameter increases; or
determining the second coefficient based on the second parameter according to a preset negative mapping relationship that the second coefficient decreases as the second parameter increases.
4. The method of claim 1 , wherein determining the one or more weighting coefficients of the predicted value of the target pixel includes:
in response to the second parameter being between a first threshold and a second threshold, determining the first coefficient as a first preset value and/or the second coefficient as a second preset value, the first threshold being greater than the second threshold;
in response to the second parameter being smaller than the second threshold, determining the first coefficient as a third preset value and/or the second coefficient as a fourth preset value, the third preset value being smaller than the first preset value, and the fourth preset value being greater than the second preset value; or
in response to the second parameter being greater than the first threshold, determining the first coefficient as a fifth preset value and/or the second coefficient as a sixth preset value, the fifth preset value being greater than the first preset value, and the sixth preset value being smaller than the second preset value.
5. The method of claim 1 , wherein determining the one or more weighting coefficients of the predicted value of the target pixel includes determining the one or more weighting coefficients according to a ratio of the first parameter to the second parameter.
6. The method of claim 5 , wherein determining the one or more weighting coefficients according to the ratio of the first parameter to the second parameter includes:
determining the first coefficient based on the ratio according to a preset negative mapping relationship that the first coefficient decreases as the ratio increases; or
determining the second coefficient based on the ratio according to a preset positive mapping relationship that the second coefficient increases as the ratio increases.
7. The method of claim 1 , wherein:
the adjacent image block is above or below the current image block;
a size of the current image block is a height of the current image block; and
a size of the adjacent image block is a height of the adjacent image block.
8. The method of claim 1 , wherein:
the adjacent image block is on a left or right side of the current image block;
a size of the current image block is a width of the current image block; and
a size of the adjacent image block is a width of the adjacent image block.
9. A computer system comprising:
a memory storing computer executable instructions; and
a processor configured to access the memory and execute the instructions to:
determine one or more weighting coefficients of a predicted value of a target pixel to be processed according to at least one of a first parameter or a second parameter, the one or more weighting coefficients including a first coefficient and a second coefficient, and determining the one or more weighting coefficients including:
determining the first coefficient based on the first parameter according to a preset negative mapping relationship that the first coefficient decreases as the first parameter increases; or
determining the second coefficient based on the first parameter according to a preset positive mapping relationship that the second coefficient increases as the first parameter increases; and
determine the predicted value of the target pixel according to the weighting coefficient, including:
determining a first predicted value of the target pixel according to a motion vector of a current image block;
determining a second predicted value of the target pixel according to a motion vector of an adjacent image block; and
obtaining the predicted value of the target pixel as a weighted sum of the first predicted value weighted by the first coefficient and the second predicted value weighted by the second coefficient;
wherein:
the target pixel is in a boundary pixel block of the current image block;
the first parameter is a size of the current image block or a distance between the target pixel and a center position of the current image block; and
the second parameter is a size of the adjacent image block of the current image block or a distance between the target pixel and a center position of the adjacent image block.
10. The computer system of claim 9 , wherein the processor is further configured to execute the instructions to:
in response to the first parameter being between a first threshold and a second threshold, determine the first coefficient as a first preset value and/or the second coefficient as a second preset value, the first threshold being greater than the second threshold;
in response to the first parameter being greater than the first threshold, determine the first coefficient as a third preset value and/or the second coefficient as a fourth preset value, the third preset value being smaller than the first preset value, and the fourth preset value being greater than the second preset value; or
in response to the first parameter being smaller than the second threshold, determine the first coefficient as a fifth preset value and/or the second coefficient as a sixth preset value, the fifth preset value being greater than the first preset value, and the sixth preset value being smaller than the second preset value.
11. The computer system of claim 9 , wherein the processor is further configured to execute the instructions to:
determine the first coefficient based on the second parameter according to a preset positive mapping relationship that the first coefficient increases as the second parameter increases; or
determine the second coefficient based on the second parameter according to a preset negative mapping relationship that the second coefficient decreases as the second parameter increases.
12. The computer system of claim 9 , wherein the processor is further configured to execute the instructions to:
in response to the second parameter being between a first threshold and a second threshold, determine the first coefficient as a first preset value and/or the second coefficient as a second preset value, the first threshold being greater than the second threshold;
in response to the second parameter being smaller than the second threshold, determine the first coefficient as a third preset value and/or the second coefficient as a fourth preset value, the third preset value being smaller than the first preset value, and the fourth preset value being greater than the second preset value; or
in response to the second parameter being greater than the first threshold, determine the first coefficient as a fifth preset value and/or the second coefficient as a sixth preset value, the fifth preset value being greater than the first preset value, and the sixth preset value being smaller than the second preset value.
13. The computer system of claim 9 , wherein the processor is further configured to execute the instructions to determine the one or more weighting coefficients according to a ratio of the first parameter to the second parameter.
14. The computer system of claim 13 , wherein the processor is further configured to execute the instructions to:
determine the first coefficient based on the ratio according to a preset negative mapping relationship that the first coefficient decreases as the ratio increases; or
determine the second coefficient based on the ratio according to a preset positive mapping relationship that the second coefficient increases as the ratio increases.
15. The computer system of claim 9 , wherein:
the adjacent image block is above or below the current image block;
a size of the current image block is a height of the current image block; and
a size of the adjacent image block is a height of the adjacent image block.
16. The computer system of claim 9 , wherein:
the adjacent image block is on a left or right side of the current image block;
a size of the current image block is a width of the current image block; and
a size of the adjacent image block is a width of the adjacent image block.