公开(公告)号：US12244860B2

公开(公告)日：2025-03-04

申请号：US18241441

申请日：2023-09-01

Applicant: LG Electronics Inc.

Inventor： Moonmo Koo ,  Seunghwan Kim ,  Mehdi Salehifar ,  Jaehyun Lim

IPC: H04N19/60 ,  H04N19/124 ,  H04N19/159 ,  H04N19/176 ,  H04N19/18 ,  H04N19/70 ,  H04N19/96

Abstract: An image decoding method according to the present document comprises a step of deriving modified transform coefficients on the basis of an inverse reduced secondary transform (RST) regarding transform coefficients regarding a target block. The inverse RST is performed on the basis of transform sets determined on the basis of a mapping relation following an intra prediction mode applied to the target block, and a transform kernel matrix selected from two transform kernel matrices included in the transform sets, respectively, and is performed on the basis of whether or not the inverse RST is applied, and a transform index indicating one of the transform kernel matrices included in the transform sets. A syntax element bin string regarding the transform index is decoded on the basis of a different context set according to the tree type regarding the division structure of the target block.

公开(公告)号：US12238339B2

公开(公告)日：2025-02-25

申请号：US17766362

申请日：2020-10-05

Applicant: LG Electronics Inc.

Inventor： Moonmo Koo ,  Jaehyun Lim ,  Seunghwan Kim ,  Mehdi Salehifar

IPC: H04N19/70 ,  H04N19/124 ,  H04N19/132 ,  H04N19/136 ,  H04N19/172 ,  H04N19/176 ,  H04N19/18 ,  H04N19/61 ,  H04N19/186

Abstract: An image decoding method, according to the present document, comprises the steps of: determining whether to parse an MTS index for applying an MTS to the current block; deriving residual samples for the current block by applying the MTS to the current block on the basis of the MTS index; and generating a reconstructed picture on the basis of the residual samples, wherein the step of determining whether to parse the MTS index includes determining the tree type of the current block, the division type of the current block, and whether zero-out for the MTS has been performed in the current block.

公开(公告)号：US12225213B2

公开(公告)日：2025-02-11

申请号：US18442607

申请日：2024-02-15

Applicant: LG ELECTRONICS INC.

Inventor： Moonmo Koo ,  Jaehyun Lim ,  Seunghwan Kim

IPC: H04N19/18 ,  H04N19/124 ,  H04N19/176 ,  H04N19/186 ,  H04N19/60 ,  H04N19/70 ,  H04N19/96

Abstract: An image decoding method according to the present document comprises the steps of: deriving a transform coefficient for a current block on the basis of residual information; deriving a residual sample by applying, to the transform coefficient, at least one of LFNST and MTS; and 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, and the LFNST index may be parsed before the MTS index.

公开(公告)号：US12212756B2

公开(公告)日：2025-01-28

申请号：US18360351

申请日：2023-07-27

Applicant: LG Electronics Inc.

Inventor： Moonmo Koo ,  Hyeongmoon Jang ,  Seunghwan Kim ,  Jaehyun Lim

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

Abstract: A method for image decoding, according to the present document, may comprise the steps of: deriving an intra prediction mode of a chroma block as 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 position in the luma block, and the specific position is set on the basis of a color format of the chroma block.

公开(公告)号：US12206856B2

公开(公告)日：2025-01-21

申请号：US17762634

申请日：2020-09-23

Applicant: LG ELECTRONICS INC.

Inventor： Moonmo Koo ,  Jaehyun Lim ,  Seunghwan Kim

IPC: H04N19/132 ,  H04N19/176 ,  H04N19/18 ,  H04N19/60

Abstract: An image decoding method according to the present document comprises the steps of: when an ISP is applied to a current block and the width or height of a sub-partition block is less than or equal to 2, applying LFNST to the transform coefficients to derive modified transform coefficients; deriving residual samples for the objective block on the basis of an inverse primary transform for the modified transform coefficients; and generating a reconstructed picture on the basis of the residual samples for the objective block, wherein when the sub-partition block is an N×2 block or a 2×N block, (M×2) or (2×M) number of modified transform coefficients are derived by applying an LFNST matrix to a predetermined number of transform coefficients in an upper left M×2 area or 2×M (M≤N) area of the sub-partition block.

公开(公告)号：US12177484B2

公开(公告)日：2024-12-24

申请号：US17428016

申请日：2020-02-06

Applicant: LG ELECTRONICS INC.

Inventor： Moonmo Koo ,  Seunghwan Kim ,  Mehdi Salehifar ,  Jaehyun Lim

IPC: H04N19/625 ,  H04N19/119 ,  H04N19/12 ,  H04N19/157 ,  H04N19/176

Abstract: A method and device for processing a video signal using a reduced transform are provided. A method for decoding a video signal includes splitting a current block into a plurality of subblocks based on a first flag for a split direction of the current block, determining a subblock, to which a transform is applied, among the plurality of subblocks based on a second flag for a position of a transform target block, determining a transform target area in the subblock, and applying an inverse transform including a horizontal transform and a vertical transform to transform coefficients of the transform target area. The transform target area is determined based on a transform type applied to the subblock and a size of the subblock.

公开(公告)号：US12137216B2

公开(公告)日：2024-11-05

申请号：US18519996

申请日：2023-11-27

Applicant: LG ELECTRONICS INC.

Inventor： Moonmo Koo ,  Mehdi Salehifar ,  Seunghwan Kim ,  Jaehyun Lim

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

Abstract: Embodiments of the present invention provide a method and apparatus for processing a video signal. A method for decoding an image signal according to an embodiment of the present invention comprises the steps of: for a current block having a width and a height different from each other, determining a modified intra prediction mode from an intra prediction mode, on the basis of a ratio between the width and the height of the current block and the intra prediction mode; determining an inverse non-separable transform set on the basis of the modified intra prediction mode; and applying an inverse non-separable transform matrix selected from the inverse non-separable transform set with respect to the top-left region of the current block, which is determined according to the width and the height of the current block.

公开(公告)号：US12108078B2

公开(公告)日：2024-10-01

申请号：US17790001

申请日：2021-01-07

Applicant: LG Electronics Inc.

Inventor： Moonmo Koo ,  Seunghwan Kim ,  Mehdi Salehifar ,  Jaehyun Lim

IPC: H04N19/11 ,  H04N19/119 ,  H04N19/132 ,  H04N19/136 ,  H04N19/176 ,  H04N19/593 ,  H04N19/61 ,  H04N19/70

CPC classification number: H04N19/593 ,  H04N19/11 ,  H04N19/119 ,  H04N19/132 ,  H04N19/136 ,  H04N19/176 ,  H04N19/61 ,  H04N19/70

Abstract: An image decoding method according to the present document may comprise the steps of: when an ISP mode is applied to a current block, remapping an intra prediction mode of the current block to a wide-angle intra prediction mode on the basis of the width and height of a first block or the width and height of a second block; performing prediction on the current block on the basis of the wide-angle intra prediction mode; and remapping the intra prediction mode of the current block to a wide-angle intra prediction mode on the basis of the width and height of the first block or the width and height of the second block, and determining an LFNST set including LFNST matrices on the basis of the wide-angle intra prediction mode, wherein the first block includes a coding block, and the second block includes a partition block.

公开(公告)号：US12095992B2

公开(公告)日：2024-09-17

申请号：US17766364

申请日：2020-10-05

Applicant: LG Electronics Inc.

Inventor： Moonmo Koo ,  Jaehyun Lim ,  Seunghwan Kim ,  Mehdi Salehifar

IPC: H04N19/18 ,  H04N19/122 ,  H04N19/124 ,  H04N19/132 ,  H04N19/136 ,  H04N19/176 ,  H04N19/184 ,  H04N19/61 ,  H04N19/96

CPC classification number: H04N19/122 ,  H04N19/124 ,  H04N19/132 ,  H04N19/136 ,  H04N19/176 ,  H04N19/18 ,  H04N19/184 ,  H04N19/61 ,  H04N19/96

Abstract: An image decoding method according to the present document can comprise the steps of: deriving a transform coefficient for a current block on the basis of residual information; determining whether an effective coefficient is in a second area that excludes the upper left first area of the current block; parsing an MTS index from a bitstream if the effective coefficient is not in the second area; and deriving a residual sample by applying, to transform coefficients of the first area, an MTS kernel derived on the basis of the MTS index.

公开(公告)号：US20240305794A1

公开(公告)日：2024-09-12

申请号：US18662814

申请日：2024-05-13

Applicant: LG ELECTRONICS INC.

Inventor： Moonmo Koo ,  Jaehyun Lim ,  Seunghwan Kim ,  Mehdi Salehifar

IPC: H04N19/18 ,  H04N19/122 ,  H04N19/14 ,  H04N19/176 ,  H04N19/70

CPC classification number: H04N19/18 ,  H04N19/122 ,  H04N19/14 ,  H04N19/176 ,  H04N19/70

Abstract: An image decoding method according to the present document may be characterized by including a step for deriving residual samples by applying at least one of an LFNST or MTS to a transform coefficient, wherein whether to parse an LFNST index indicating an LFNST kernel is determined on the basis of whether zeroing-out has been performed on the LFNST, whether to parse an MTS index indicating an MTS kernel is determined on the basis of whether zeroing-out has been performed on the MTS, the MTS index is parsed on the basis of a color index of the current block being a luma component, and the LFNST index is parsed regardless of the color index of the current block.