公开(公告)号：US12041239B2

公开(公告)日：2024-07-16

申请号：US17431908

申请日：2020-03-12

Applicant: LG Electronics Inc.

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

IPC: H04N19/132 ,  H04N19/167 ,  H04N19/176 ,  H04N19/196 ,  H04N19/60

CPC classification number: H04N19/132 ,  H04N19/167 ,  H04N19/176 ,  H04N19/196 ,  H04N19/60

Abstract: An image decoding method according to the present document comprises a step for deriving a residual sample, wherein the step for deriving the residual sample comprises the steps of: deriving a zero out block for a current block; deriving a context model for last significant coefficient location information on the basis of the width or height of the current block; deriving a value of a last significant coefficient location on the basis of the context model; and deriving the last significant coefficient location on the basis of a value of the last significant coefficient location information and the width or height of the zero out block.

公开(公告)号：US12022094B2

公开(公告)日：2024-06-25

申请号：US17764465

申请日：2020-10-08

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.

公开(公告)号：US12010342B2

公开(公告)日：2024-06-11

申请号：US17429518

申请日：2020-02-10

Applicant: LG Electronics Inc.

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

IPC: H04N7/12 ,  H04N19/105 ,  H04N19/176 ,  H04N19/46 ,  H04N19/60

CPC classification number: H04N19/60 ,  H04N19/105 ,  H04N19/176 ,  H04N19/46

Abstract: Embodiments in the present specification provide a method and device for processing video signal including steps of: obtaining a sub-block transform (SBT) flag indicating whether a SBT is applied, wherein the SBT represents a transform applied to a transform unit corresponding to one of subblocks split from a coding unit; determining a variable value related to a transform target region based on the SBT flag and a size value of the transform unit, wherein if the SBT flag equals to 1 and the size value is greater than a threshold value, the variable value is determined as the threshold value; obtaining position information of a last significant coefficient according to a scan order within the transform unit, wherein the position information of the last significant coefficient is coded based on the variable value; and performing an inverse-transform based on the position information of the last significant coefficient.

公开(公告)号：US20240114159A1

公开(公告)日：2024-04-04

申请号：US18386135

申请日：2023-11-01

Applicant: LG ELECTRONICS INC.

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

IPC: H04N19/44 ,  H04N19/132 ,  H04N19/159 ,  H04N19/176 ,  H04N19/625 ,  H04N19/70

CPC classification number: H04N19/44 ,  H04N19/132 ,  H04N19/159 ,  H04N19/176 ,  H04N19/625 ,  H04N19/70

Abstract: The present invention relates to a video signal decoding method based on a Multiple Transform Selection (MTS). The method may comprise the steps of: parsing a first syntax element representing whether MTS applies to the inverse transformation of a current block, wherein the MTS represents a transform mode which uses a transform type other than a default transform type predefined for the current block; by performing inverse quantization on the current block, deriving an inverse-quantized transform coefficient array having the width and the height of the current block; determining, on the basis of the first syntax element, a vertical transform type applying to the vertical direction of the current block, and a horizontal transform type applying to the horizontal direction of the current block; and, by performing inverse transformation on the inverse-quantized transform coefficient array by using the vertical transform type and the horizontal transform type, deriving a residual sample array having the width and the height of the current block.

公开(公告)号：US11870982B2

公开(公告)日：2024-01-09

申请号：US18084127

申请日：2022-12-19

Applicant: LG ELECTRONICS INC.

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

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

CPC classification number: 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：US11838549B2

公开(公告)日：2023-12-05

申请号：US17970027

申请日：2022-10-20

Applicant: LG Electronics Inc.

Inventor： Junghak Nam ,  Jaehyun Lim ,  Moonmo Koo ,  Seunghwan Kim

IPC: H04N19/60 ,  H04N19/122 ,  H04N19/159 ,  H04N19/176 ,  H04N19/18

CPC classification number: H04N19/60 ,  H04N19/122 ,  H04N19/159 ,  H04N19/176 ,  H04N19/18 ,  H04N19/593 ,  H04N19/119

Abstract: An image decoding method according to the present document comprises the steps of: acquiring prediction-related information and residual-related information for a current block; deriving transform coefficients for the current block on the basis of the residual-related information; and generating residual samples of the current block on the basis of the transform coefficients, wherein the residual-related information includes low-frequency non-separable transform (LFNST) index information indicating information relating to non-separable transform for a low-frequency transform coefficient of the current block on the basis of a matrix-based intra prediction (MIP) flag.

公开(公告)号：US11818350B2

公开(公告)日：2023-11-14

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

CPC classification number: 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：US11770560B2

公开(公告)日：2023-09-26

申请号：US18094047

申请日：2023-01-06

Applicant: LG Electronics Inc.

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

IPC: H04N19/00 ,  H04N19/625 ,  H04N19/129 ,  H04N19/176 ,  H04N19/70

CPC classification number: H04N19/625 ,  H04N19/129 ,  H04N19/176 ,  H04N19/70

Abstract: Embodiments of the present invention provide a video signal processing method and device. Particularly, a method for decoding a video signal, may comprise the steps of: checking whether a transfer skip is applied to a current block; obtaining, from a video signal, a transform index for indicating a transform type set applied to the current block when the transform skip is not applied to the current block, wherein the transform type set includes transform types applied to the current block in horizontal and vertical directions; checking whether the transform type set includes DCT2; determining a region to which a primary transform is applied based on a checking result; and performing an inverse transform on the region to which the primary transform is applied in the horizontal and vertical directions using the transform types included in the transform type set.

公开(公告)号：US11750817B2

公开(公告)日：2023-09-05

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 ,  H04N19/176 ,  H04N19/186

CPC classification number: H04N19/132 ,  H04N19/159 ,  H04N19/176 ,  H04N19/186

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：US11729425B2

公开(公告)日：2023-08-15

申请号：US17551794

申请日：2021-12-15

Applicant: LG ELECTRONICS INC.

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

IPC: H04N19/625 ,  H04N19/132 ,  H04N19/176 ,  H04N19/70

CPC classification number: H04N19/625 ,  H04N19/132 ,  H04N19/176 ,  H04N19/70

Abstract: A method for decoding a video signal based on reduced transform includes the steps of: obtaining, from the video signal, a transform index indicating transform kernels applied to horizontal and vertical directions of a current block; determining a region in which a transform is applied to the current block based on the transform kernels indicated by the transform index and a size of the current block; deriving, as zero, coefficients of a remaining region other than the region to which the transform is applied within the current block; and performing an inverse transform on the region to which the transform is applied using the transform kernels indicated by the transform index.