Patent ID: 11962762
Assignee: KT CORPORATION
Field: Audio-visual technology (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. A method of decoding a video signal, the method comprising:
determining whether at least one non-zero residual coefficient is included in a current transform block;
decoding residual coefficients of the current transform block;
performing an inverse-quantization for the current transform block;
determining whether an inverse-transform is skipped for the current transform block or not; and
obtaining residual samples of the current transform block by performing or skipping the inverse-transform for the current transform block,
wherein the residual coefficients in the current transform block are decoded in a unit of a sub-block,
wherein a size of the sub-block is determined based on whether at least one of a width or a height of the current transform block is less than 4,
wherein in response that at least one of the width or the height of the current transform block is less than 4, the size of the sub-block is determined as 2×2, 2×8, or 8×2,
wherein in response that both the width and the height of the current block are equal to or greater than 4, the size of the sub-block is determined as 4×4,
wherein whether a transform skip flag, indicating whether the inverse-transform is skipped or not, of the current transform block is present in a bitstream or not is determined based on whether a coding block, including the current transform block, is partitioned into a plurality of transform blocks in a horizontal direction or a vertical direction, and
wherein in response that the current transform block is one of the plurality of transform blocks generated by partitioning the coding block in the horizontal direction or the vertical direction, the transform skip flag of the current transform block is not present in the bitstream, and skipping the inverse-transform is not allowed for the current transform block.