Video signal processing method and device using block DPCM prediction method

1 . A device for decoding a video signal, the device comprising:

a processor,

wherein the processor is configured to:

when a condition is satisfied, obtain intra block-based delta pulse code modulation (BDPCM) information indicating whether a BDPCM is applied to a current block,

when the intra BDPCM information indicates that the BDPCM is applied to the current block:

skip obtaining transform skip information indicating whether a transform is applied to a transform block corresponding to the current block, and infer a value of the transform skip information as a value indicating that the transform is not applied to the transform block,

obtain intra BDPCM direction information indicating a prediction direction of the BDPCM applied to the current block,

reconstruct the current block based on the intra BDPCM direction information, and

wherein the intra BDPCM information and the intra BDPCM direction information are obtained for a luma component regardless of a chroma component.

2 . The device of claim 1 ,

wherein the condition includes a case that a width of a current block is less than or equal to a first value, and a height of the current block is less than or equal to a second value,

wherein the first value and the second value are related to a maximum block size that allows transform skip.

3 . The device of claim 1 ,

wherein the processor is configured to:

obtain BDPCM enable information indicating whether the BDPCM is enabled,

wherein the condition includes a case that the BDPCM enable information indicates that the BDPCM is enabled.

4 . The device of claim 3 , wherein the BDPCM enable information is signaled in a sequence parameter set.

5 . The device of claim 1 , wherein the intra BDPCM direction information indicates one of a horizontal direction or a vertical direction.

6 . The device of claim 5 ,

when the intra BDPCM direction information indicates the horizontal direction, an intra prediction mode of the current block is an intra prediction mode corresponding to the horizontal direction, and

when the intra BDPCM direction information indicates the vertical direction, the intra prediction mode of the current block is an intra prediction mode corresponding to the vertical direction.

7 . The device of claim 6 ,

wherein when a value of the intra BDPCM direction information is 0, the intra BDPCM direction information indicates the horizontal direction,

wherein when the value of the intra BDPCM direction information is 1, the intra BDPCM direction information indicates the vertical direction.

8 . The device of claim 7 , wherein the intra prediction mode of the current block is included in intra prediction mode candidates for signaling an intra prediction mode of a neighboring block to be reconstructed after the current block.

9 . A device for encoding video signal, the device comprising:

a processor,

wherein the processor is configured to:

obtain a bitstream to be decoded by a decoder using a decoding method, the decoding method comprising:

when a condition is satisfied, obtaining intra block-based delta pulse code modulation (BDPCM) information indicating whether a BDPCM is applied to a current block;

when the intra BDPCM information indicates that the BDPCM is applied to the current block:

skipping obtaining transform skip information indicating whether a transform is applied to a transform block corresponding to the current block, and inferring a value of the transform skip information as a value indicating that the transform is not applied to the transform block;

obtaining intra BDPCM direction information indicating a prediction direction of the BDPCM applied to the current block; and

reconstructing the current block based on the intra BDPCM direction information,

wherein the intra BDPCM information and the intra BDPCM direction information are obtained for a luma component regardless of a chroma component.

10 . The device of claim 9 ,

wherein the condition includes a case that a width of a current block is less than or equal to a first value, and a height of the current block is less than or equal to a second value,

wherein the first value and the second value are related to a maximum block size that allows transform skip.

11 . The device of claim 9 ,

the decoding method further comprising:

obtaining BDPCM enable information indicating whether the BDPCM is enabled,

wherein the condition includes a case that the BDPCM enable information indicates that the BDPCM is enabled.

12 . The device of claim 11 ,

wherein the BDPCM enable information is signaled in a sequence parameter set.

13 . The device of claim 9 ,

wherein the intra BDPCM direction information indicates one of a horizontal direction or a vertical direction.

14 . The device of claim 13 ,

when the intra BDPCM direction information indicates the horizontal direction, an intra prediction mode of the current block is an intra prediction mode corresponding to the horizontal direction, and

when the intra BDPCM direction information indicates the vertical direction, the intra prediction mode of the current block is an intra prediction mode corresponding to the vertical direction.

15 . The device of claim 14 ,

wherein when a value of the intra BDPCM direction information is 0, the intra BDPCM direction information indicates the horizontal direction,

wherein when the value of the intra BDPCM direction information is 1, the intra BDPCM direction information indicates the vertical direction.

16 . The device of claim 15 ,

wherein the intra prediction mode of the current block is included in intra prediction mode candidates for signaling an intra prediction mode of a neighboring block to be reconstructed after the current block.

17 . A method for obtaining a bitstream, method comprising:

when a condition is satisfied, obtaining intra block-based delta pulse code modulation (BDPCM) information indicating whether a BDPCM is applied to a current block;

when the intra BDPCM information indicates that the BDPCM is applied to the current block:

skipping obtaining transform skip information indicating whether a transform is applied to a transform block corresponding to the current block, and inferring a value of the transform skip information as a value indicating that the transform is not applied to the transform block;

obtaining intra BDPCM direction information indicating a prediction direction of the BDPCM applied to the current block,

wherein the intra BDPCM information and the intra BDPCM direction information are obtained for a luma component regardless of a chroma component; and

obtaining the bitstream including information for reconstructing the current block.

18 . A method for decoding a video signal, the method comprising:

when a condition is satisfied, obtaining intra block-based delta pulse code modulation (BDPCM) information indicating whether a BDPCM is applied to a current block;

when the intra BDPCM information indicates that the BDPCM is applied to the current block:

skipping obtaining transform skip information indicating whether a transform is applied to a transform block corresponding to the current block, and inferring a value of the transform skip information as a value indicating that the transform is not applied to the transform block;

obtaining intra BDPCM direction information indicating a prediction direction of the BDPCM applied to the current block; and

reconstructing the current block based on the intra BDPCM direction information,

wherein the intra BDPCM information and the intra BDPCM direction information are obtained for a luma component regardless of a chroma component.