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Transform-based image coding method and device

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Bibliographic Details
Title: Transform-based image coding method and device
Patent Number: 12262,015
Publication Date: March 25, 2025
Appl. No: 17/762150
Application Filed: September 21, 2020
Abstract: An image decoding method includes a step of deriving a residual sample, wherein the step of deriving the residual sample includes the steps of: when a current block is divided into sub-partition blocks, deriving a transform kernel for an inverse primary transform applied to a sub-partition block based on a horizontal or a vertical length of the sub-partition block; and deriving the residual sample from transform coefficients based on the transform kernel.
Inventors: LG ELECTRONICS INC. (Seoul, KR)
Assignees: LG Electronics Inc. (Seoul, KR)
Claim: 1. An image decoding method performed by a decoding apparatus, the method comprising: obtaining, from a bitstream, residual information and a low-frequency non-separable transform (LFNST) index; deriving transform coefficients for a current block based on the residual information; deriving residual samples for the current block by applying an inverse primary transform to the transform coefficients using transform kernels for vertical and horizontal; and generating a reconstructed picture based on the residual samples, wherein based on the current block being divided into sub-partition blocks as an intra sub-partitions (ISP) is applied and the LFNST index being equal to 0, the transform kernel for vertical is determined by checking a vertical length of a sub-partition block divided from the current block, and the transform kernel for horizontal is determined by checking a horizontal length of the sub-partition block, and wherein based on the current block being divided into the sub-partition blocks as the ISP is applied and the LFNST index being greater than 0, the transform kernels for vertical and horizontal are respectively determined as DCT-2.
Claim: 2. An image encoding method performed by an encoding apparatus, the method comprising: deriving residual samples for a current block; deriving transform coefficients by applying a primary transform to the residual samples using transform kernels for vertical and horizontal; and encoding an LFNST index and residual information including information on the transform coefficients, wherein based on the current block being divided into sub-partition blocks as an intra sub-partitions (ISP) is applied and the LFNST index being equal to 0, the transform kernel for vertical is determined by checking a vertical length of a sub-partition block divided from the current block, and the transform kernel for horizontal is determined by checking a horizontal length of the sub-partition block, and wherein based on the current block being divided into the sub-partition blocks as the ISP is applied and the LFNST index being greater than 0, the transform kernels for vertical and horizontal are respectively determined as DCT-2.
Claim: 3. A transmission method of data for an image, the method comprising: obtaining a bitstream for the image, wherein the bitstream is generated based on deriving residual samples for a current block, deriving transform coefficients by applying a primary transform to the residual samples using transform kernels for vertical and horizontal, and encoding an LFNST index and residual information including information on the transform coefficients; and transmitting the data comprising the bitstream, wherein based on the current block being divided into sub-partition blocks as an intra sub-partitions (ISP) is applied and the LFNST index being equal to 0, the transform kernel for vertical is determined by checking a vertical length of a sub-partition block divided from the current block, and the transform kernel for horizontal is determined by checking a horizontal length of the sub-partition block, and wherein based on the current block being divided into the sub-partition blocks as the ISP is applied and the LFNST index being greater than 0, the transform kernels for vertical and horizontal are respectively determined as DCT-2.
Patent References Cited: 11539952 December 2022 Egilmez
2013/0107950 May 2013 Guo et al.
2019/0110061 April 2019 Park et al.
2021/0099702 April 2021 Egilmez
2022/0038741 February 2022 Nam
2022/0150545 May 2022 Egilmez
2022/0159259 May 2022 Fan
2022/0345690 October 2022 Zhao
2022/0394255 December 2022 Kang
2023/0142928 May 2023 Koo
2023/0269374 August 2023 Fan
2024/0146966 May 2024 Koo
104244010 December 2014
105120272 December 2015
107071437 August 2017
109417636 March 2019
111615830 September 2020
111684809 September 2020
20100095992 September 2010
101617109 April 2016
20180136481 December 2018
WO 2018/066990 April 2018
WO2019009618 January 2019
WO 2019/117639 June 2019
WO 2019/125035 June 2019
WO 2020/260313 December 2020
Other References: Bross et al., “Versatile Video Coding (Draft 6),” JVET-O2001-vE, Presented at Joint Video Experts Team (JVET) of ITU-T SG 16 WP 3 and ISO/IEC JTC 1/SC 29/WG 11, 15th Meeting: Gothenburg, SE, Jul. 3-12, 2019, 455 pages. cited by applicant
Zhou et al., “Non-CE6: Simplification with new LFNST transform basis,” JVET-O0620, Presented at Joint Video Experts Team (JVET) of ITU-T SG 16 WP 3 and ISO/IEC JTC 1/SC 29/WG 11, 15th Meeting: Gothenburg, SE, Jul. 3-12, 2019, 4 pages. cited by applicant
Bross et al., “Versatile Video Coding (Draft 5),” JVET-N1001-v10, Presented at Joint Video Experts Team (JVET) of ITU-T SG 16 WP 3 and 1S0/IEC JTC 1/SC 29/WG 11, 14th Meeting: Geneva, CH, Mar. 19-27, 2019, 406 pages. cited by applicant
Bross et al., “Versatile Video Coding (Draft 6),” JVET-O2001-v1, Presented at Joint Video Experts Team (JVET) of ITU-T SG 16 WP 3 and ISO/IEC JTC 1/SC 29/WG 11, 15th Meeting: Gothenburg, SE, Jul. 3-12, 2019, 406 pages. cited by applicant
Chen et al., “Algorithm description for Versatile Video Coding and Test Model 5 (VTM 5),” JVET-N1002-v2, Presented at Joint Video Experts Team (JVET) of ITU-T SG 16 WP 3 and ISO/IEC JTC I/SC 29/WG 11, 14th Meeting: Geneva, CH, Mar. 19-27, 2019, 76 pages. cited by applicant
Extended European Search Report in European Appln. No. 20866694.1, dated Oct. 7, 2022, 11 pages. cited by applicant
Koo et al., “Low Frequency Non-Separable Transform (LFNST),” Picture Coding Symposium (PCS). IEEE, Nov. 2019, 5 pages. cited by applicant
Koo et al., “Non-CE6: Block size restriction of LFNST,” JVET-O0213, Presented at Joint Video Experts Team (JVET) ofITU-T SG 16 WP 3 and 1S0/IEC JTC 1/SC 29/WG 11, 15th Meeting: Gothenburg, SE, Jul. 3-12, 2019, 5 pages. cited by applicant
Office Action in Indian Appln. No. 202217021895, dated Aug. 23, 2022, 6 pages. cited by applicant
Tsukuba et al., “Non-CE6: TU/TB-level LFNST index coding,” JVET-O0352-v2, Presented at Joint Video Experts Team (JVET) of ITU-T SG 16 WP 3 and 1S0/IEC JTC 1/SC 29/WG 11, 15th Meeting: Gothenburg, SE, Jul. 3-12, 2019, 8 pages. cited by applicant
De-Luxan-Hernandez et al., “ Non-CE6: Combination of JVET-P0196 and JVET-P0392 on applying LFNST for ISP Blocks and simplifying the transform signalling,” JVET-P1026-v1, Joint Video Experts Team (JVET) of ITU-T SG 16 WP 3 and ISO/IEC JTC 1/SC 29/WG 11, Meeting #16, Oct. 1-11, 2019, 4 pages. cited by applicant
De-Luxan-Hernandez et al., “Non-CE6: Combination of ISP and LFNST,” JVET-P0392-v1, Joint Video Experts Team (JVET) of ITU-T SG 16 WP 3 and ISO/IEC JTC 1/SC 29/WG 11, Meeting #16, Oct. 1-11, 2019, 5 pages. cited by applicant
Lainema, “CE6-related: Latency reduction for LFNST signalling,” JVET-P0196-v2, Joint Video Experts Team (JVET) of ITU-T SG 16 WP 3 and ISO/IEC JTC 1/SC 29/WG 11, Meeting #16, Oct. 1-11, 2019, 4 pages. cited by applicant
Notice of Allowance in European Appln. No. 20866694.1, mailed on Jan. 15, 2024, 8 pages. cited by applicant
Office Action in Chinese Appln. No. 202080072344.7, mailed on Apr. 11, 2024, 16 pages (with English translation). cited by applicant
Bross et al., “Versatile Video Coding (Draft 3),” JVET-L1001-v9, Joint Video Experts Team (JVET) of ITU-T SG 16 WP 3 and ISO/IEC JTC 1/SC 29/WG 11, 12th Meeting: Macao, CN, Oct. 3-12, 2018, 238 pages. cited by applicant
De-Luxán-Hernández et al., “CE3: Intra Sub-Partitions Coding Mode (Tests 1.1.1 and 1.1.2),” JVET-M0102-v5, Joint Video Experts Team (JVET) of ITU-T SG 16 WP 3 and ISO/IEC JTC 1/SC 29/WG 11, 13th Meeting: Marrakech, MA, Jan. 9-18, 2019, 14 pages. cited by applicant
Notice of Allowance in Chinese Appln. No. 202080072344.7, mailed on Oct. 31, 2024, 5 pages. cited by applicant
Office Action in Korean Appln. No. 10-2022-7008836, mailed on Oct. 25, 2024, 7 pages. cited by applicant
Primary Examiner: Kir, Albert
Attorney, Agent or Firm: Fish & Richardson P.C.
Accession Number: edspgr.12262015
Database: USPTO Patent Grants
Description
Abstract:An image decoding method includes a step of deriving a residual sample, wherein the step of deriving the residual sample includes the steps of: when a current block is divided into sub-partition blocks, deriving a transform kernel for an inverse primary transform applied to a sub-partition block based on a horizontal or a vertical length of the sub-partition block; and deriving the residual sample from transform coefficients based on the transform kernel.