Image encoding/decoding method and device using same
The image decoding method according to the present invention comprises the steps of: determining the availability of a block adjacent to a current block; configuring a merge candidate list for the current block on the basis of the result of the determined availability; and performing motion compensation for the current block on the basis of the merge candidate list, wherein the step of determining availability comprises the steps of inducing block availability information on the adjacent block and inducing the availability of motion information on the adjacent block, and the step of determining the availability of the adjacent block is such that when there is more than one adjacent block, the availability of adjacent blocks can be determined in accordance with a predetermined order restriction.
1. A video decoding method comprising:
determining availability of a neighboring block of a current block;
constructing a merge candidate list for the current block based on a result of determining the availability; and
performing motion compensation for the current block based on the merge candidate list,
wherein the determining of the availability comprises
deriving block availability information on the neighboring block based on whether a prediction mode of the neighboring block is an intra prediction mode or not;
resetting the derived block availability information on the neighboring block based on parallel merge level information indicating a size of a block in which a parallel merge processing is applicable; and
deriving availability of motion information on the neighboring block using the reset block availability information,
wherein in response to a position of the current block being defined as (xP, yP), the neighboring block comprises a first block comprising a pixel present at (xP−1, yP+nPSH), a second block comprising a pixel present at (xP−1, yP+nPSH−1), a third block comprising a pixel present at (xP+nPSW, yP−1), a fourth block comprising a pixel present at (xP+nPSW−1, yP−1), and a fifth block comprising a pixel present at (xP−1, yP−1), and
wherein the block availability information on the neighboring block indicates whether a corresponding neighboring block is usable for an inter prediction of the current block and the availability of motion information on the neighboring block indicates whether motion information of a corresponding neighboring block is included in the merge candidate list.
2. The video decoding method of claim 1 , wherein the determining of the availability of the neighboring block sets block availability information on the second block to false (0) in response to a partition form of the current block being one of PART_N×2N, PART_nL×2N and PART_nR×2N, and an index partldx of the current block in a coding unit being 1.
3. The video decoding method of claim 1 , wherein the determining of the availability of the neighboring block sets block availability information on the fourth block to false (0) in response to a partition form of the current block being one of PART_2N×N, PART_2N×nU and PART_2N×nD, and an index partldx of the current block in a coding unit being 1.
4. The video decoding method of claim 1 , wherein the deriving of the block availability information sets the block availability information to false (0) in response to the neighboring block being encoded in an intra-mode.
5. The video decoding method of claim 1 , wherein the deriving of the availability of the motion information sets availability of motion information on the third block to false (0) in response to block availability information on the fourth block being true (1) and motion information on the fourth block and the motion information on the third block being the same.
6. The video decoding method of claim 1 , wherein the deriving of the availability of the motion information sets availability of motion information on the first block to false (0) in response to block availability information on the second block being true (1) and motion information on the second block and the motion information on the first block being the same.
7. The video decoding method of claim 1 , wherein the deriving of the availability of the motion information sets availability of motion information on the fifth block to false (0) in response to block availability information on the second block being true (1) and motion information on the second block and the motion information on the fifth block being the same.
8. The video decoding method of claim 1 , wherein the deriving of the availability of the motion information sets availability of motion information on the fifth block to false (0) in response to block availability information on the fourth block being true (1) and motion information on the fourth block and the motion information on the fifth block being the same.
9. The video decoding method of claim 1 , wherein the deriving of the availability of the motion information sets availability of motion information on the fifth block to false (0) in response to availability of motion information on all of the first block, the second block, the third block and the fourth block being true (1).
10. The video decoding method of claim 1 , wherein the deriving of the availability of the motion information sets availability of motion information on the fourth block to false (0) in response to block availability information on the second block being true (1) and motion information on the second block and the motion information on the fourth block being the same.
11. A video encoding method comprising:
determining availability of a neighboring block of a current block;
constructing a merge candidate list for the current block based on a result of determining the availability; and
performing motion compensation for the current block based on the merge candidate list,
wherein the determining of the availability comprises
deriving block availability information on the neighboring block based on whether a prediction mode of the neighboring block is an intra prediction mode or not;
resetting the derived block availability information on the neighboring block based on parallel merge level information indicating a size of a block in which a parallel merge processing is applicable; and
deriving availability of motion information on the neighboring block using the reset block availability information,
wherein in response to a position of the current block being defined as (xP, yP), the neighboring block comprises a first block comprising a pixel present at (xP−1, yP+nPSH), a second block comprising a pixel present at (xP−1, yP+nPSH−1), a third block comprising a pixel present at (xP+nPSW, yP−1), a fourth block comprising a pixel present at (xP+nPSW−1, yP−1), and a fifth block comprising a pixel present at (xP−1, yP−1), and
wherein the block availability information on the neighboring block indicates whether a corresponding neighboring block is usable for an inter prediction of the current block and the availability of motion information on the neighboring block indicates whether motion information of a corresponding neighboring block is included in the merge candidate list.
12. A non-transitory computer-readable storage medium storing a bitstream that is formed by a video encoding method, the video encoding method comprising:
determining availability of a neighboring block of a current block;
constructing a merge candidate list for the current block based on a result of determining the availability; and
performing motion compensation for the current block based on the merge candidate list,
wherein the determining of the availability comprises
deriving block availability information on the neighboring block based on whether a prediction mode of the neighboring block is an intra prediction mode or not;
resetting the derived block availability information on the neighboring block based on parallel merge level information indicating a size of a block in which a parallel merge processing is applicable; and
deriving availability of motion information on the neighboring block using the derived block availability information,
wherein in response to a position of the current block being defined as (xP, yP), the neighboring block comprises a first block comprising a pixel present at (xP−1, yP+nPSH), a second block comprising a pixel present at (xP−1, yP+nPSH−1), a third block comprising a pixel present at (xP+nPSW, yP−1), a fourth block comprising a pixel present at (xP+nPSW−1, yP−1), and a fifth block comprising a pixel present at (xP−1, yP−1), and
wherein the block availability information on the neighboring block indicates whether a corresponding neighboring block is usable for an inter prediction of the current block and the availability of motion information on the neighboring block indicates whether motion information of a corresponding neighboring block is included in the merge candidate list.