公开(公告)号：US20220377336A1

公开(公告)日：2022-11-24

申请号：US17864666

申请日：2022-07-14

Applicant: LG Electronics Inc.

Inventor： Mehdi SALEHIFAR ,  Seunghwan KIM ,  Jaehyun LIM ,  Moonmo KOO

IPC: H04N19/122 ,  H04N19/167 ,  H04N19/176 ,  H04N19/91

Abstract: An image decoding method performed by means of a decoding device according to the present disclosure comprises the steps of: deriving transform coefficients of a target block from a bitstream; deriving a non-separable secondary transform (NSST) index with respect to the target block; performing inverse transform with respect to the transform coefficients of the target block on the basis of the NSST index and thus deriving residual samples of the target block; and generating a reconstructed picture on the basis of the residual samples.

公开(公告)号：US20220377335A1

公开(公告)日：2022-11-24

申请号：US17761794

申请日：2020-09-21

Applicant: LG ELECTRONICS INC.

Inventor： Moonmo KOO ,  Jaehyun LIM ,  Seunghwan KIM

IPC: H04N19/122 ,  H04N19/176 ,  H04N19/167

Abstract: An image decoding method according to the present document comprises a step of deriving a corrected transform coefficient, wherein the step of deriving the corrected transform coefficient comprises the steps of: determining whether the transform coefficient exists in a second region excluding the upper left first region of the current block; parsing a LFNST index on the basis of the determined result; and deriving the corrected transform coefficient on the basis of the LFNST index and a LFNST matrix, wherein the LFNST index can be parsed on the basis of the current block being divided into a plurality of sub-partition blocks, and the absence of the transform coefficient in some of the individual second regions for the plurality of sub-partition blocks.

公开(公告)号：US20220264103A1

公开(公告)日：2022-08-18

申请号：US17730758

申请日：2022-04-27

Applicant: LG Electronics Inc.

Inventor： Moonmo KOO ,  Hyeongmoon JANG ,  Seunghwan KIM ,  Jaehyun LIM

IPC: H04N19/132 ,  H04N19/159 ,  H04N19/18 ,  H04N19/186 ,  H04N19/176

Abstract: An image decoding method according to the present document comprises the steps of: on the basis that an intra prediction mode of a chroma block is a cross-component linear model (CCLM) mode, updating the intra prediction mode of the chroma block on the basis of an intra prediction mode of a luma block corresponding to the chroma block; and determining an LFNST set including LFNST matrices on the basis of the updated intra prediction mode, wherein the updated intra prediction mode is derived as an intra prediction mode corresponding to a specific location in the luma block, and on the basis that the intra prediction mode corresponding to the specific location is an MIP mode, the updated intra prediction mode is updated to an intra planner mode.

公开(公告)号：US20220264102A1

公开(公告)日：2022-08-18

申请号：US17729917

申请日：2022-04-26

Applicant: LG Electronics Inc.

Inventor： Moonmo KOO ,  Hyeongmoon JANG ,  Seunghwan KIM ,  Jaehyun LIM

IPC: H04N19/132 ,  H04N19/159 ,  H04N19/186 ,  H04N19/176

Abstract: An image decoding method according to the present document comprises the steps of: on the basis of an intra prediction mode of a chroma block being a cross-component linear model (CCLM) mode and an intra prediction mode of a luma block corresponding to the chroma block being a palette mode, updating the intra prediction mode of the chroma block to an intra DC mode; on the basis of the updated intra prediction mode, determining an LFNST set including LFNST matrices; and performing LFNST on the chroma block on the basis of an LFNST matrix derived from the LFNST set, wherein the intra DC mode is an intra prediction mode corresponding to a specific location within the luma block.

公开(公告)号：US20220248056A1

公开(公告)日：2022-08-04

申请号：US17729597

申请日：2022-04-26

Applicant: LG ELECTRONICS INC.

Inventor： Seunghwan KIM ,  Medhi Salehifar ,  Moonmo KOO ,  Jaehyun LIM

IPC: H04N19/61 ,  H04N19/11 ,  H04N19/176 ,  H04N19/593

Abstract: The present disclosure, in a method of decoding a video signal, provides a method including checking whether a transform skip is applied to a current block; acquiring a transform index indicating transform types applied to a horizontal direction and a vertical direction of the current block from among a plurality of predefined transform types from the video signal when the transform skip is not applied to the current block; and performing an inverse primary transform on the current block using the transform types indicated by the transform index, wherein the transform types applied to the horizontal direction and the vertical direction of the current block are determined from among transform types defined according to an intra prediction mode of the current block based on the transform index.

公开(公告)号：US20220248055A1

公开(公告)日：2022-08-04

申请号：US17727516

申请日：2022-04-22

Applicant: LG Electronics Inc.

Inventor： Moonmo KOO ,  Hyeongmoon JANG ,  Seunghwan KIM ,  Jaehyun LIM

IPC: H04N19/61 ,  H04N19/159 ,  H04N19/176 ,  H04N19/186 ,  H04N19/167

Abstract: An image decoding method according to the present document comprises the steps of: updating an intra-prediction mode of a chroma block on the basis of an intra-prediction mode of a luma block corresponding to the chroma block on the basis of the intra-prediction mode of the chroma block being a cross-component linear model (CCLM) mode; and determining a LFNST set including LFNST matrixes on the basis of the updated intra-prediction mode, wherein the updated intra-prediction mode is derived as an intra-prediction mode corresponding to a specific position in the luma block, and the updated intra-prediction mode is updated as an intra-DC mode on the basis of the intra-prediction mode, that corresponds to the specific position, being an intra-block copy (IBC) mode.

公开(公告)号：US20220217402A1

公开(公告)日：2022-07-07

申请号：US17700271

申请日：2022-03-21

Applicant: LG ELECTRONICS INC.

Inventor： Moonmo KOO ,  Seunghwan KIM ,  Jaehyun LIM

IPC: H04N19/61 ,  H04N19/176 ,  H04N19/18 ,  H04N19/186

Abstract: An image decoding method according to the present document comprises a step for deriving a modified transform coefficient, wherein the step for deriving the modified transform coefficient comprises a step for determining whether or not to parse an LFNST index on the basis of whether or not the width and height of a current block satisfy a condition about whether the LFNST can be applied, and whether or not the condition about whether the LFNST can be applied is satisfied is determined on the basis of a tree type and a color format of the current block and whether or not an ISP is applied to the current block.

公开(公告)号：US20220217364A1

公开(公告)日：2022-07-07

申请号：US17707000

申请日：2022-03-29

Applicant: LG Electronics Inc.

Inventor： Moonmo KOO ,  Jaehyun LIM ,  Seunghwan KIM ,  Mehdi SALEHIFAR

IPC: H04N19/18 ,  H04N19/119 ,  H04N19/132 ,  H04N19/176 ,  H04N19/186 ,  H04N19/60 ,  H04N19/70 ,  H04N19/129 ,  H04N19/96

Abstract: An image decoding method according to the present document comprises: a residual coding step for parsing residual information received in a residual coding level and arranging transform coefficients for a current block according to a predetermined scanning order; a step for deriving residual samples by applying at least one of LFNST or MTS to the transform coefficients; and a step for generating a reconstructed picture on the basis of the residual samples, wherein the LFNST is performed on the basis of an LFNST index indicating an LFNST kernel, the MTS is performed on the basis of an MTS index indicating an MTS kernel, the LFNST index and the MTS index are signaled in a coding unit level, and the MTS index is signaled immediately after the signaling of the LFNST index.

公开(公告)号：US20220210426A1

公开(公告)日：2022-06-30

申请号：US17587910

申请日：2022-01-28

Applicant: LG Electronics Inc.

Inventor： Moonmo KOO ,  Seunghwan KIM ,  Jaehyun LIM

IPC: H04N19/132 ,  H04N19/159 ,  H04N19/176 ,  H04N19/18 ,  H04N19/30 ,  H04N19/46

Abstract: An image decoding method according to the present document comprises the steps of: receiving a quantized transform coefficient for a target block and a transform index for a non-separable secondary transform; dequantizing the quantized transform coefficients to derive transform coefficients; deriving modified transform coefficients on the basis of a matrix operation of a transform kernel matrix in a transform set indicated by the transform index and a transform coefficient list corresponding to the magnitude of dequantized transform coefficients; clipping the modified transform coefficients to a predetermined range of values; and deriving residual samples for the target block on the basis of an inverse primary transform with respect to the modified transform coefficients clipped.

公开(公告)号：US20220191546A1

公开(公告)日：2022-06-16

申请号：US17689277

申请日：2022-03-08

Applicant: LG Electronics Inc.

Inventor： Moonmo KOO ,  Jaehyun LIM ,  Seunghwan KIM

IPC: H04N19/60 ,  H04N19/124 ,  H04N19/159 ,  H04N19/176 ,  H04N19/18 ,  H04N19/70

Abstract: An image decoding method comprises the steps of: deriving transform coefficients through inverse quantization on the basis of quantized transform coefficients for a target block; deriving modified transform coefficients on the basis of an inverse reduced secondary transform (RST) for the transform coefficients; and generating a restoration picture on the basis of residual samples for the target block, on the basis of an inverse primary transform for the modified transform coefficients, wherein the inverse RST is performed on the basis of: transform sets determined by a mapping relation according to an intra prediction mode applied to the target block; and a transform kernel matrix selected from among two transform kernel matrices included in each of the transform sets, and is performed on the basis of: whether the inverse RST is applied; and a transform index for indicating any one of the transform kernel matrices included in the transform sets.