Video coding method and device using merge candidate
In a video encoding/decoding method and device according to the present invention, a merge candidate of a current block may be determined, a merge candidate list may be configured on the basis of the merge candidate, motion information of the current block may be derived from the merge candidate list, and the motion information may be used to perform inter prediction of the current block.
1. A method of decoding a video, comprising:
determining a merge candidate of a current block in the video;
constructing a merge candidate list of the current block based on the merge candidate;
deriving motion information of the current block based on the merge candidate list; and
performing inter prediction of the current block using the motion information,
wherein the current block is divided, based on a predetermined division line, into a plurality of partitions including a first partition and a second partition,
wherein at least one of the first partition or the second partition has a triangular shape,
wherein a pixel of the current block is predicted using at least one of a first prediction block or a second prediction block of the current block,
wherein the motion information of the current block is derived for each of the first partition and the second partition,
wherein the first prediction block is obtained based on the motion information of the first partition and the second prediction block is obtained based on the motion information of the second partition,
wherein a pixel at a first position in the current block is predicted using only one of the first prediction block or the second prediction block, and
wherein a pixel at a second position in the current block is predicted by weighted average of a pixel in the first prediction block and a pixel in the second prediction block.
2. The method of claim 1 , wherein the division is performed based on a flag indicating whether to divide the current block into the plurality of partitions.
3. The method of claim 2 , wherein the flag is derived based on a predetermined encoding parameter, and
wherein the encoding parameter includes at least one of a slice type, a type of an inter mode, a block size/shape, or a ratio of a width and a height of a block.
4. The method of claim 1 , wherein the first partition and the second partition belonging to the current block share the constructed merge candidate list.
5. The method of claim 4 , wherein the merge candidate list includes at least one of a spatial merge candidate, a temporal merge candidate, or a combined merge candidate.
6. The method of claim 5 , wherein the motion information is derived based on a merge index of the current block, and
wherein the merge index is signaled, from an encoding apparatus, for each of the first partition and the second partition.
7. The method of claim 1 , wherein a weight for the weighted average is one of [7:1], [6:2], [4:4], [2:6], or [1:7].
8. The method of claim 7 , wherein the weight is selectively applied according to a position of the pixel in the first prediction block and a position of the pixel in the second prediction block.
9. A method of encoding a video, comprising:
determining a merge candidate of a current block in the video;
constructing a merge candidate list of the current block based on the merge candidate; and
performing inter prediction of the current block based on motion information from the merge candidate list,
wherein the current block is divided, based on a predetermined division line, into a plurality of partitions including a first partition and a second partition,
wherein at least one of the first partition or the second partition has a triangular shape,
wherein a pixel of the current block is predicted using at least one of a first prediction block or a second prediction block of the current block,
wherein the motion information of the current block is determined for each of the first partition and the second partition,
wherein the first prediction block is obtained based on the motion information of the first partition and the second prediction block is obtained based on the motion information of the second partition,
wherein a pixel at a first position in the current block is predicted using only one of the first prediction block or the second prediction block, and
wherein a pixel at a second position in the current block is predicted by weighted average of a pixel in the first prediction block and a pixel in the second prediction block.
10. A non-transitory computer-readable storage medium for storing data associated with a video signal, comprising:
a bitstream to be decoded by a decoding method comprising:
determining a merge candidate of a current block;
constructing a merge candidate list of the current block based on the merge candidate;
deriving motion information of the current block based on the merge candidate list; and
performing inter prediction of the current block using the motion information,
wherein the current block is divided, based on a predetermined division line, into a plurality of partitions including a first partition and a second partition,
wherein at least one of the first partition or the second partition has a triangular shape,
wherein a pixel of the current block is predicted using at least one of the first prediction block or a second prediction block of the current block,
wherein the motion information of the current block is derived for each of the first partition and the second partition,
wherein the first prediction block is obtained based on the motion information of the first partition and the second prediction block is obtained based on the motion information of the second partition,
wherein a pixel at a first position in the current block is predicted using only one of the first prediction block or the second prediction block, and
wherein a pixel at a second position in the current block is predicted by weighted average of a pixel in the first prediction block and a pixel in the second prediction block.