Granted Patent B2

US 12,200,215 · App. 18/501,251 · Granted Jan 14, 2025

Inventors: Jung Won Kang (Daejeon, KR); Ha Hyun Lee (Seoul, KR); Sung Chang Lim (Daejeon, KR); Jin Ho Lee (Daejeon, KR); Hui Yong Kim (Daejeon, KR); Byeung Woo Jeon (Seongnam-si, KR); Jee Yoon Park (Seoul, KR)

Assignees: Electronics and Telecommunications Research Institute; RESEARCH & BUSINESS FOUNDATION SUNGKYUNKWAN UNIVERSITY

H04N19/12H04N19/176H04N19/46H04N19/619

Abstract

Claims (26)

1. A method of decoding an image, the method comprising:

obtaining maximum transform skip size information from a bitstream;

obtaining transform skip information of a current block from a bitstream on the basis of the maximum transform skip size information;

obtaining multiple transform selection information of the current block on the basis of the transform skip information from the bitstream;

performing inverse transform on the current block on the basis of the multiple transform selection information to generate a residual block of the current block;

generating a reconstructed block of the current block on the basis of the residual block,

wherein the multiple transform selection information is used to set each of a horizontal transform type and a vertical transform type,

wherein the transform skip information is used for both a luma component and a chroma component, and

wherein the multiple transform selection information is used only for the luma component.

2. A method of encoding an image, the method comprising:

determining a maximum transform skip size;

determining whether to perform transform skip of a current block;

when the transform skip is not performed on the current block, determining a horizontal transform type and a vertical transform type of the current block;

performing the transform on the current block on the basis of the horizontal transform type and the vertical transform type to generate transform coefficients of the current block;

encoding at least one of maximum transform skip size information indicating the maximum transform skip size, transform skip information indicating whether to perform the transform skip of the current block and multiple transform selection information indicating the horizontal transform type and the vertical transform type of the current block; and

encoding the transform coefficients of the current block,

wherein the transform skip information is used for both a luma component and a chroma component, and

wherein the multiple transform selection information is used only for the luma component.

3. A non-transitory computer readable recording medium storing a bitstream decoded by an image decoding apparatus,

wherein the bitstream includes maximum transform skip size information, transform skip information of a current block, multiple transform selection information of the current block and transform coefficients of the current block;

the maximum transform skip size information indicates a maximum transform skip size;

the transform skip information indicates whether inverse transform is performed on the current block;

the multiple transform selection information indicates a horizontal transform type and a vertical transform type applied to inverse transform of the current block; and

the image decoding apparatus obtains the multiple transform selection information on the basis of the transform skip information,

wherein the transform skip information is used for both a luma component and a chroma component, and

wherein the multiple transform selection information is used only for the luma component.

Assignments (1)

Priority Claims (1)

Continuity (3)

References Cited (34)