公开(公告)号：US20240314325A1

公开(公告)日：2024-09-19

申请号：US18676359

申请日：2024-05-28

Applicant: LG Electronics Inc.

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

IPC: H04N19/132 ,  H04N19/105 ,  H04N19/176 ,  H04N19/18

CPC classification number: H04N19/132 ,  H04N19/105 ,  H04N19/176 ,  H04N19/18

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：US20240187601A1

公开(公告)日：2024-06-06

申请号：US18438023

申请日：2024-02-09

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：US20240129467A1

公开(公告)日：2024-04-18

申请号：US18543091

申请日：2023-12-18

Applicant: LG Electronics Inc.

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

IPC: H04N19/122 ,  H04N19/167 ,  H04N19/176 ,  H04N19/18 ,  H04N19/91

CPC classification number: H04N19/122 ,  H04N19/167 ,  H04N19/176 ,  H04N19/18 ,  H04N19/91

Abstract: The present disclosure provides a method for reconstructing a video signal, which includes: obtaining a transform coefficient block by performing an entropy decoding and a dequantization for a current block; deriving a secondary transform corresponding to a specific area in the transform coefficient block, wherein the specific area represents an area including a top-left block of the transform coefficient block; performing an inverse secondary transform for each of subblocks within the specific area using the secondary transform; performing an inverse primary transform for a block which the inverse secondary transform is applied to; and reconstructing the current block using a block which the primary inverse transform is applied to.

公开(公告)号：US20240098305A1

公开(公告)日：2024-03-21

申请号：US18388108

申请日：2023-11-08

Applicant: LG Electronics Inc.

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

IPC: H04N19/61 ,  H04N19/11 ,  H04N19/122 ,  H04N19/124 ,  H04N19/129 ,  H04N19/132 ,  H04N19/159 ,  H04N19/176 ,  H04N19/18

CPC classification number: H04N19/61 ,  H04N19/11 ,  H04N19/122 ,  H04N19/124 ,  H04N19/129 ,  H04N19/132 ,  H04N19/159 ,  H04N19/176 ,  H04N19/18

Abstract: An image decoding method according to the present specification comprises the steps of: deriving transform coefficients through inverse quantization on the basis of quantized transform coefficient for a target block; deriving modified transform coefficients on the basis of inverse reduced secondary transform (RST) of the transform coefficients; and generating a reconstructed picture on the basis of residual samples for the target block on the basis of an inverse primary transform of the modified transform coefficients, wherein the step of deriving the modified transform coefficients is characterized in deriving 16 modified transform coefficients by applying a transform kernel matrix to 8 transform coefficients in a 4×4 region of the target block.

公开(公告)号：US20240064337A1

公开(公告)日：2024-02-22

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 ,  H04N19/18 ,  H04N19/176 ,  H04N19/132 ,  H04N19/172 ,  H04N19/136 ,  H04N19/124 ,  H04N19/61

CPC classification number: H04N19/70 ,  H04N19/18 ,  H04N19/176 ,  H04N19/132 ,  H04N19/172 ,  H04N19/136 ,  H04N19/124 ,  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：US20240031573A1

公开(公告)日：2024-01-25

申请号：US18369493

申请日：2023-09-18

Applicant: LG ELECTRONICS INC

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

IPC: H04N19/122 ,  H04N19/167 ,  H04N19/176 ,  H04N19/61

CPC classification number: H04N19/122 ,  H04N19/167 ,  H04N19/176 ,  H04N19/61

Abstract: The embodiments of the present disclosure provides a method and apparatus for video signal processing. A method for decoding an image signal according to an embodiment of the present disclosure may include determining an input length and an output length of a non-separable transform based on a height and a width of a current block; determining a non-separable transform matrix corresponding to the input length and the output length of a non-separable transform; and applying the non-separable transform matrix to coefficients by a number of the input length in the current block, wherein the height and the width of a current block is greater than or equal to 8, wherein, if each of the height and the width of a current block is equal to 8, the input length of the non-separable transform is determined as 8.

公开(公告)号：US20230345006A1

公开(公告)日：2023-10-26

申请号：US18217328

申请日：2023-06-30

Applicant: LG ELECTRONICS INC.

Inventor： Mehdi SALEHIFAR ,  Seunghwan KIM

IPC: H04N19/132 ,  H04N19/105 ,  H04N19/159 ,  H04N19/176

CPC classification number: H04N19/132 ,  H04N19/105 ,  H04N19/159 ,  H04N19/176

Abstract: An image decoding method according to the present document can comprise the steps of: receiving flag information indicating whether a matrix-based intra prediction (MIP) is used with respect to a current block; receiving matrix-based intra prediction (MIP) mode information on the basis of the flag information; generating an intra prediction sample for the current block on the basis of the MIP mode information; and generating restoration samples for the current block on the basis of the intra prediction samples.

公开(公告)号：US20230133403A1

公开(公告)日：2023-05-04

申请号：US18089100

申请日：2022-12-27

Applicant: LG ELECTRONICS INC.

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

IPC: H04N19/18 ,  H04N19/11 ,  H04N19/122 ,  H04N19/124 ,  H04N19/129 ,  H04N19/159 ,  H04N19/176 ,  H04N19/184 ,  H04N19/593 ,  H04N19/61 ,  H04N19/91

Abstract: An image decoding method according to the present disclosure includes deriving transform coefficients through dequantization based on the quantized transform coefficients for the target block; deriving modified transform coefficients based on an inverse reduced secondary transform (RST) for the transform coefficients; deriving residual samples for the target block based on an inverse primary transform for the modified transform coefficients; and generating a reconstructed samples based on the residual samples, and prediction samples derived based on an intra prediction mode for the target block, wherein the inverse RST is performed based on a transform kernel matrix selected from a transform set including a plurality of transform kernel matrices, the transform set is determined based on a mapping relationship according to the intra prediction mode applied to the target block, and a plurality of intra prediction modes including the intra prediction mode of the target block are mapped to one transform set.

公开(公告)号：US20230063796A1

公开(公告)日：2023-03-02

申请号：US17789483

申请日：2020-12-28

Applicant: LG ELECTRONICS INC.

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

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

Abstract: An image decoding method according to the present document comprises the steps of: receiving residual information in a bitstream, wherein the residual information includes a transform skip flag for each individual component of the current block; deriving corrected transform coefficients, wherein the step for deriving includes a step for setting a variable indicating whether effective coefficients exist at positions other than that of a DC component of the current block to 0 when even one of the values of the transform skip flags for the individual components is 0, and a step for parsing an LFNST index on the basis of the variable being 0; and deriving an LFNST kernel for applying LFNST on the basis of the LFNST index, wherein the variable being 0 may indicate that effective coefficients exist at positions other than that of the DC component.

公开(公告)号：US20220400266A1

公开(公告)日：2022-12-15

申请号：US17775693

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: determining whether or not an effective coefficient is present in a second area not including an upper-left first area of a current block; parsing an MTS index from a bitstream on the basis that the effective coefficient is not present in the second area; and deriving residual samples for the current block by applying a transform kernel, which is derived on the basis of the MTS index, to transform coefficients in the first area, wherein the MTS index can be parsed on the basis that the effective coefficient, which is present in a scan sub-block which is scanned for the effective coefficient, is not present in the second area.