公开(公告)号：US20230412843A1

公开(公告)日：2023-12-21

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

CPC classification number: 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 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：US20230224467A1

公开(公告)日：2023-07-13

申请号：US18122552

申请日：2023-03-16

Applicant: LG ELECTRONICS INC.

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

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

CPC classification number: H04N19/18 ,  H04N19/132 ,  H04N19/176

Abstract: A method for decoding an image by a decoding device according to the present invention comprises the steps of: deriving, from a bit stream, transform coefficients of a block to be decoded; deriving residual samples of the block to be decoded, on the basis of a selective transform of the transform coefficients; and generating a reconstructed picture on the basis of the residual samples of the block to be decoded and prediction samples of the block to be decoded, wherein the selective transform is performed on the basis of a modified transform matrix, the modified transform matrix comprises a matrix including a modified basis vector, and the modified basis vector contains a certain number of elements selected from N elements.

公开(公告)号：US20230199220A1

公开(公告)日：2023-06-22

申请号：US18109495

申请日：2023-02-14

Applicant: LG Electronics Inc.

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

IPC: H04N19/625 ,  H04N19/129 ,  H04N19/176 ,  H04N19/18

CPC classification number: H04N19/625 ,  H04N19/129 ,  H04N19/176 ,  H04N19/18

Abstract: The present disclosure provides a method of reconstructing a video signal based on a reduced secondary transform, which includes: obtaining a secondary transform index from the video signal; deriving a secondary transform corresponding to the secondary transform index, wherein the secondary transform represents a reduced secondary transform, and the reduced secondary transform represents a transform outputting L (L

公开(公告)号：US20230164359A1

公开(公告)日：2023-05-25

申请号：US18094047

申请日：2023-01-06

Applicant: LG Electronics Inc.

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

IPC: H04N19/625 ,  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：US20230164309A1

公开(公告)日：2023-05-25

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：US20220408094A1

公开(公告)日：2022-12-22

申请号：US17775683

申请日：2020-11-09

Applicant: LG Electronics Inc.

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

IPC: H04N19/132 ,  H04N19/186 ,  H04N19/18 ,  H04N19/176 ,  H04N19/46

Abstract: An image decoding method according to the present document comprises the steps of: deriving flag information indicating whether valid coefficients are present in a second area excluding a first area of the upper left corner of the current block; parsing an MTS index from a bitstream on the basis of the flag information indicating the absence of valid coefficients in the second area; and deriving residual samples for the current block by applying a conversion kernel derived on the basis of the MTS index to conversion coefficients of the first area, wherein the flag information may be derived by determining, for each scan sub-block in which the valid coefficients are scanned, whether the valid coefficients are present in the second area.

公开(公告)号：US20220394300A1

公开(公告)日：2022-12-08

申请号：US17282120

申请日：2019-10-01

Applicant: LG ELECTRONICS INC.

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

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

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：US20220353514A1

公开(公告)日：2022-11-03

申请号：US17863074

申请日：2022-07-12

Applicant: LG Electronics Inc.

Inventor： Mehdi SALEHIFAR ,  Seunghwan KIM

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

Abstract: An image decoding method according to the present document may comprise the steps of: receiving flag information indicating whether or not matrix-based intra prediction (MIP) is to be used for a current block; receiving matrix-based intra prediction (MIP) mode information on the basis of the flag information; generating intra prediction samples for the current block on the basis of the MIP mode information; and generating reconstructed samples for the current block on the basis of the intra prediction samples, wherein a syntax element bin string for the MIP mode information is binarized by using a truncated binarization method.

公开(公告)号：US20220345726A1

公开(公告)日：2022-10-27

申请号：US17748847

申请日：2022-05-19

Applicant: LG ELECTRONICS INC.

Inventor： Jie ZHAO ,  Seung Hwan KIM ,  Mehdi SALEHIFAR

IPC: H04N19/186 ,  H04N19/124 ,  H04N19/176 ,  H04N19/132 ,  H04N19/18 ,  H04N19/12 ,  H04N19/463

Abstract: Provided are an image encoding/decoding method and device. The image decoding method performed by the image decoding device, according to the present disclosure, may comprise the steps of: determining a residual sample of a current block; and resetting the value of the residual sample on the basis of whether a color space transform is applied. The step for resetting the value of the residual block may be performed on the basis of a half value of a chroma residual sample value.

公开(公告)号：US20220312013A1

公开(公告)日：2022-09-29

申请号：US17637516

申请日：2020-09-15

Applicant: LG ELECTRONICS INC.

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

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

Abstract: An image decoding method according to the present document may comprise the steps of: if a current block is partitioned into sub-partition transform blocks, deriving a prediction sample of the current block on the basis of intra prediction mode information; determining an LFNST set including LFNST matrices on the basis of an intra prediction mode derived from the intra prediction mode information; selecting one of the LFNST matrices on the basis of the LFNST set and the LFNST index; deriving transform coefficients for the sub-partition transform blocks on the basis of the selected LFNST matrix; and deriving residual samples for the current block on the basis of the transform coefficients.