Method and device for efficiently applying transform skip mode to data block

Abstract

Disclosed are a method and an apparatus for efficiently applying a transform skip mode to a transform block. According to an embodiment of the present invention, a video decoding apparatus determines, based on transform skip information associated with a current block, the transform skip information being decoded from a bitstream, whether a subblock for which transform is skipped and one or more subblocks to which transform is applied are included in the current block. When determining that the current block includes the subblock for which the transform is skipped and the one or more subblocks to which the transform is applied are included in the current block, the video decoding apparatus decodes a first residual subblock using a decoding procedure not involving inverse transform for the subblock for which the transform is skipped, and decodes one or more second residual subblocks using a decoding procedure involving the inverse transform for the one or more subblocks to which the transform is applied. The video decoding apparatus adds the first residual subblock and the one or more second residual subblocks to a prediction block to reconstruct the current block. Representative drawing: FIGS.A-D