Granted Patent B2

US 12,701,255 · App. 18/802,604 · Granted Aug 4, 2026

Inventor: Bae Keun Lee (Seoul, KR)

Assignee: KT CORPORATION

H04N19/46H04N19/103H04N19/119H04N19/132H04N19/147H04N19/169H04N19/174H04N19/176H04N19/18H04N19/187H04N19/30H04N19/44H04N19/96

Abstract

Claims (39)

1 . A method of decoding a video, the method comprising:

decoding a coded block flag indicating whether at least one non-zero transform coefficient exists in a current block;

decoding transform coefficients of the current block based on the coded block flag indicating that the at least one non-zero transform coefficient exists in the current block;

obtaining inverse-quantized transform coefficients by performing inverse-quantization on the transform coefficients of the current block;

determining, based on a transform skip flag indicating whether to skip inverse-transform, whether to skip the inverse-transform for the current block or not;

obtaining residual samples of the current block by skipping or performing the inverse-transform on the inverse-quantized transform coefficients in the current block; and

obtaining reconstruction sample by summing the residual samples and prediction samples,

wherein, in response to a case where the current block is one of two partitions generated by binary-partitioning a coding block in either a horizontal direction or a vertical direction, the transform skip flag is not parsed from a bitstream and it is determined not to skip the inverse-transform for the current block.

2 . The method of claim 1 , wherein the transform coefficients included in the current block are obtained based on a pre-defined scanning order, and

wherein the pre-defined scanning order is a diagonal scanning order.

3 . The method of claim 2 , wherein the transform coefficients included in the current block are obtained in units of sub-blocks,

wherein a shape of a sub-block is adaptively determined based on a shape of the current block when the current block is constituted with a pre-determined number of samples, and

wherein the pre-determined number is 16, 32 or 64.

4 . The method of claim 1 , wherein when it is determined not to skip the inverse-transform, the method further comprises determining a horizontal transform type and a vertical transform type of the current block, and

wherein the horizontal transform type and the vertical transform type are determined as a DCT (Discrete Cosine Transform) basis kernel or a DST (Discrete Sine Transform) basis kernel.

5 . A method of encoding a video, the method comprising:

obtaining residual samples of a current block by subtracting prediction samples from original samples;

obtaining transform coefficients by skipping or performing transform on the residual samples of the current block;

obtaining quantized transform coefficients by performing quantization on the transform coefficients;

encoding the quantized transform coefficients of the current block;

encoding a coded block flag indicating whether a non-zero quantized transform coefficient exists in the current block,

wherein it is determined whether to encode a transform skip flag indicating whether the transform is skipped or not, and

wherein, in response to a case where the current block is one of two partitions generated by binary-partitioning a coding block in either a horizontal direction or a vertical direction, it is determined not to skip the transform for the current block and the transform skip flag is not encoded into a bitstream.

6 . The method of claim 5 , wherein the quantized transform coefficients included in the current block are encoded based on a pre-defined scanning order, and

wherein the pre-defined scanning order is a diagonal scanning order.

7 . The method of claim 6 , wherein the quantized transform coefficients included in the current block are encoded in units of sub-blocks,

wherein a shape of a sub-block is adaptively determined based on a shape of the current block when the current block is constituted with a pre-determined number of samples, and

wherein the pre-determined number is 16, 32 or 64.

8 . The method of claim 5 , wherein the method further comprises determining a horizontal transform type and a vertical transform type of the current block, and

wherein the horizontal transform type and the vertical transform type are determined as a DCT (Discrete Cosine Transform) basis kernel or a DST (Discrete Sine Transform) basis kernel.

9 . A non-transitory computer-readable medium for storing data associated with a video signal, comprising:

a data stream stored in the non-transitory computer-readable medium, the data stream being encoded by an encoding method comprising:

obtaining residual samples of a current block by subtracting prediction samples from original samples;

obtaining transform coefficients by skipping or performing transform on the residual samples of the current block;

obtaining quantized transform coefficients by performing quantization on the transform coefficients;

encoding the quantized transform coefficients of the current block; and

encoding a coded block flag indicating whether a non-zero quantized transform coefficient exists in the current block,

wherein it is determined whether to encode a transform skip flag indicating whether the transform is skipped or not, and

wherein, in response to a case where the current block is one of two partitions generated by binary-partitioning a coding block in either a horizontal direction or a vertical direction, it is determined not to skip the transform for the current block and the transform skip flag is not encoded into the data stream.

Assignments (1)

Priority Claims (3)

Continuity (4)

References Cited (111)