Method for dividing prediction block, encoding device, and decoding device
A method for dividing a prediction block, an encoding device, and a decoding device, is disclosed. The method includes: acquiring a manner of division into the prediction block, where the manner of division into the prediction block is a horizontal division manner, a vertical division manner, or a square division manner, determining a horizontal division size and a vertical division size according to the manner of division into the prediction block, and dividing the prediction block into at least one prediction subblock according to the horizontal division size and the vertical division size.
1. A method for dividing a prediction block of an image, the method comprising:
acquiring a size of a horizontal side and a size of a vertical side that are of the prediction block;
acquiring a base size;
determining a size of a horizontal side of a prediction subblock according to a magnitude relationship between the size of the horizontal side of the prediction block and the base size or a magnitude relationship between the size of the vertical side of the prediction block and the base size;
determining a size of a vertical side of the prediction subblock according to the magnitude relationship between the size of the horizontal side of the prediction block and the base size or the magnitude relationship between the size of the vertical side of the prediction block and the base size; and
dividing the prediction block into at least one such prediction subblock according to the size of the horizontal side of the prediction subblock and the size of the vertical side of the prediction sunblock, and
the size of the horizontal side of the prediction subblock being determined according to the magnitude relationship between the size of the horizontal side of the prediction block and the base size or the magnitude relationship between the size of the vertical side of the prediction block and the base size and the size of the vertical side of the prediction subblock being determined according to the magnitude relationship between the size of the horizontal side of the prediction block and the base size or the magnitude relationship between the size of the vertical side of the prediction block and the base size comprising:
setting the size of the horizontal side of the prediction subblock to the size of the horizontal side of the prediction block and setting the size of the vertical side of the prediction subblock to the size of the vertical side of the prediction block when a preset condition is met; and
setting the size of the horizontal side of the prediction subblock to the base size and setting the size of the vertical side of the prediction subblock to the base size when the preset condition is not met, the preset condition comprising either that a ratio of the size of the horizontal side of the prediction block to the base size is less than or equal to one, or that a ratio of the size of the vertical side of the prediction block to the base size is less than or equal to one.
2. The method of claim 1 , wherein determining the size of the horizontal side of the prediction subblock according to the magnitude relationship between the size of the horizontal side of the prediction block and the base size or the magnitude relationship between the size of the vertical side of the prediction block and the base size, determining the size of the vertical side of the prediction subblock according to the magnitude relationship between the size of the horizontal side of the prediction block and the base size or the magnitude relationship between the size of the vertical side of the prediction block and the base size, and dividing the prediction block into at least one such prediction subblock according to the size of the horizontal side of the prediction subblock and the size of the vertical side of the prediction subblock comprises dividing the prediction block into one prediction subblock according to the size of the horizontal side of the prediction block and the size of the vertical side of the prediction block if one of the following conditions is true:
the size of the horizontal side of the prediction block is less than the base size;
the size of the vertical side of the prediction block is less than the base size;
the size of the horizontal side of the prediction block is greater than the base size but is not divisible by the base size; and
the size of the vertical side of the prediction block is greater than the base size but is not divisible by the base size.
3. The method of claim 1 , wherein the method further comprises obtaining motion information according to the prediction subblock.
4. The method of claim 3 , wherein obtaining the motion information according to the prediction subblock comprises obtaining the motion information from a reference view image or a texture image according to the prediction subblock.
5. A decoding device for dividing a prediction block of an image, the decoding device comprising:
a memory comprising instructions; and
a processor coupled to the memory and configured to execute the instructions to:
acquire a size of a horizontal side and a size of a vertical side that are of the prediction block;
acquire a base size;
determine a size of a horizontal side of a prediction subblock according to a magnitude relationship between the size of the horizontal side of the prediction block and the base size or a magnitude relationship between the size of the vertical side of the prediction block and the base size;
determine a size of a vertical side of the prediction subblock according to the magnitude relationship between the size of the horizontal side of the prediction block and the base size or the magnitude relationship between the size of the vertical side of the prediction block and the base size;
divide the prediction block into at least one such prediction subblock according to the size of the horizontal side of the prediction subblock and the size of the vertical side of the prediction subblock;
set the size of the horizontal side of the prediction subblock to the size of the horizontal side of the prediction block and setting the size of the vertical side of the prediction subblock to the size of the vertical side of the prediction block when a preset condition is met; and
set the size of the horizontal side of the prediction subblock to the base size and setting the size of the vertical side of the prediction subblock to the base size when the preset condition is not met, the preset condition comprising either that a ratio of the size of the horizontal side of the prediction block to the base size is less than or equal to one, or a ratio of the size of the vertical side of the prediction block to the base size is less than or equal to one.
6. The decoding device of claim 5 , wherein the processor is further configured to execute the instructions to divide the prediction block into one prediction subblock according to the size of the horizontal side of the prediction block and the size of the vertical side of the prediction block if one of the following conditions is true:
the size of the horizontal side of the prediction block is less than the base size;
the size of the vertical side of the prediction block is less than the base size;
the size of the horizontal side of the prediction block is greater than the base size but is not divisible by the base size; and
the size of the vertical side of the prediction block is greater than the base size but is not divisible by the base size.
7. The decoding device of claim 5 , wherein the processor is further configured to execute the instructions to obtain motion information according to the prediction subblock.
8. The decoding device of claim 7 , wherein the processor is further configured to execute the instructions to obtain the motion information from a reference view image or a texture image according to the prediction subblock.