Video signal processing method and device

1 . A method of decoding an image, comprising:

dividing, based on a triple division, a first coding block into three second coding blocks;

dividing, based on a binary division, one of the three second coding blocks into two third coding blocks;

obtaining a prediction block for the one of the two third coding blocks; and

reconstructing the one of the two third coding blocks based on the prediction block,

wherein a largest second coding block among the three second coding blocks has a size greater than a size of each of the other two of the three second coding blocks,

wherein the other two of the three second coding blocks have a same size,

wherein the largest second coding block is located between the other two of the three second coding blocks,

wherein whether the one of the three second coding blocks is divided based on the binary division is determined based on first information signaled via the bitstream,

wherein in response to the first information indicates that the one of the three second coding blocks is divided based on the binary division, the one of the three second coding blocks is divided into the two third coding blocks in a horizontal direction or a vertical direction, and

wherein, in response to the one of the three second coding blocks is the largest second coding block, the binary division with a same division direction as a division direction of the triple division for the first coding block is not allowed for the largest second coding block.

2 . The method of claim 1 , wherein the restriction, with respect to the allowance of the same division direction as the division direction of the triple division, is applied only to the one of the three second coding blocks which is located between the other two of the three second coding blocks.

3 . The method of claim 2 , wherein one of the horizontal direction or the vertical direction is selected based on second information selectively signaled via the bitstreams, and

wherein in response to the one of the three second coding blocks is the largest second coding block, signaling of the second information for the largest second coding block is omitted.

4 . The method of claim 1 , wherein, in response to a product of a width and a height of the first coding block being equal to 64, the triple division is not allowed for the first coding block.

5 . The method of claim 4 , wherein, in response to a product of a width and a height of a second coding block being equal to 32, the binary division is not allowed for the second coding block.

6 . The method of claim 1 , wherein decoding a third coding block comprises:

determining an intra prediction mode of the third coding block from a first candidate list or a second candidate list, a number of candidates included in the first candidate list being less than a number of candidates included in the second candidate list; and

performing intra prediction of the third coding block based on the intra prediction mode.

7 . The method of claim 6 , wherein the number of candidates included in the second candidate list is 5.

8 . The method of claim 7 , wherein one of the first candidate list or the second candidate list is adaptively used according to third information signaled from the bitstream.

9 . A method of encoding an image, comprising:

dividing, based on a triple division, a first coding block into three second coding blocks;

dividing, based on a binary division, one of the three second coding blocks into two third coding blocks;

obtaining a prediction block for the one of the two third coding blocks; and

encoding a residual block for the one of the two third coding blocks, the residual block being obtained based on the prediction block,

wherein a largest second coding block among the three second coding blocks has a size greater than a size of each of the other two of the three second coding blocks,

wherein the other two of the three second coding blocks have a same size,

wherein the largest second coding block is located between the other two of the three second coding blocks,

wherein first information, indicating whether the one of the three second coding blocks is divided by the binary division is encoded into the bitstream, and

wherein, in response to the one of the three second coding blocks is the largest second coding block, the binary division with a same division direction as a division direction of the triple division for the first coding block is not allowed for the largest second coding block.

10 . A device for transmitting compressed video data, comprising:

a processor configured to obtain the compressed video data, and

a transmitter configured to transmit the compressed video data,

wherein obtaining the compressed video data comprises:

dividing, based on a triple division, a first coding block into three second coding blocks;

dividing, based on a binary division, one of the three second coding blocks into two third coding blocks;

obtaining a prediction block for the one of the two third coding blocks; and

encoding a residual block for the one of the two third coding blocks, the residual block being obtained based on the prediction block,

wherein a largest second coding block among the three second coding blocks has a size greater than a size of each of the other two of the three second coding blocks,

wherein the other two of the three second coding blocks have a same size,

wherein the largest second coding block is located between the other two of the three second coding blocks,

wherein first information, indicating whether the one of the three second coding blocks is divided by the binary division is encoded into the bitstream, and

wherein, in response to the one of the three second coding blocks is the largest second coding block, the binary division with a same division direction as a division direction of the triple division for the first coding block is not allowed for the largest second coding block.