公开(公告)号：US12244861B2

公开(公告)日：2025-03-04

申请号：US18545642

申请日：2023-12-19

Applicant: LG Electronics Inc.

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

IPC: H04N19/00 ,  H04N19/105 ,  H04N19/124 ,  H04N19/176 ,  H04N19/18 ,  H04N19/60 ,  H04N19/70

Abstract: An image decoding method performed by means of a decoding device according to the present invention comprises the steps of: deriving quantized transform coefficients with respect to a target block from a bitstream; performing inverse quantization with respect to the quantized transform coefficients with respect to the target block and deriving transform coefficients; deriving residual samples with respect to the target block on the basis of reduced inverse transform with respect to the transform coefficients; and generating a reconstructed picture on the basis of the residual samples with respect to the target block and prediction samples with respect to the target block. The reduced inverse transform is performed on the basis of a reduced inverse transform matrix. The reduced inverse transform matrix is a non-square matrix of which the number of columns is smaller than the number of rows.

公开(公告)号：US12231688B2

公开(公告)日：2025-02-18

申请号：US18232287

申请日：2023-08-09

Applicant: LG ELECTRONICS INC.

Inventor： Moonmo Koo ,  Seunghwan Kim ,  Jaehyun Lim

IPC: H04N11/02 ,  H04N19/122 ,  H04N19/132 ,  H04N19/176 ,  H04N19/18 ,  H04N19/61 ,  H04N19/70

Abstract: An image decoding method according to the present document may include the steps of: deriving the position of the final significant coefficient in the current block and transform coefficients for the current block on the basis of residual information; determining whether the index of a sub-block including the final significant coefficient is 0 and whether the position of the final significant coefficient in the sub-block is greater than 0; determining whether a significant coefficient exists in a second area excluding a first area at the upper left end of the current block; and parsing an LFNST index from a bitstream when the position of the final significant coefficient is determined to be greater than 0 in the sub-block in which the index is 0, and the significant coefficient does not exist in the second area.

公开(公告)号：US12200257B2

公开(公告)日：2025-01-14

申请号：US18383732

申请日：2023-10-25

Applicant: LG Electronics Inc.

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

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

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：US12184859B2

公开(公告)日：2024-12-31

申请号：US17773234

申请日：2020-11-02

Applicant: LG Electronics Inc.

Inventor： Moonmo Koo ,  Seunghwan Kim ,  Jaehyun Lim

IPC: H04N19/132 ,  H04N19/176 ,  H04N19/18 ,  H04N19/186 ,  H04N19/96

Abstract: An image decoding method according to the present document comprises the steps of: applying LFNST to transform coefficients to derive modified transform coefficients; deriving residual samples for a target 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, wherein the step of deriving the modified transform coefficients can comprise the steps of parsing an LFNST index on the basis of the current block tree type being a dual tree chroma, and deriving the modified transform coefficients on the basis of the LFNST index and an LFNST matrix.

公开(公告)号：US12166977B2

公开(公告)日：2024-12-10

申请号：US18518829

申请日：2023-11-24

Applicant: LG ELECTRONICS INC.

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

IPC: H04L43/16 ,  H04N19/11 ,  H04N19/176 ,  H04N19/61 ,  H04N19/70

Abstract: Embodiments of the disclosure provide a method and apparatus for processing a video signal. Particularly, a method for decoding a video signal according to an embodiment of the disclosure may include: determining, among predefined secondary transform sets based on intra-prediction modes of a current block, a secondary transform set applied to the current block; obtaining a first syntax element indicating a secondary transform matrix applied to the current block in the determined secondary transform set; deriving a secondary inverse-transformed block by performing a secondary inverse transform on a left top region of the current block by using the secondary transform matrix specified by the first syntax element; and deriving a residual block of the current block by performing a primary inverse transform on the secondary inverse-transformed block using a primary transform matrix of the current block.

公开(公告)号：US12081756B2

公开(公告)日：2024-09-03

申请号：US18377146

申请日：2023-10-05

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：US12034933B2

公开(公告)日：2024-07-09

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 ,  H04N19/105 ,  H04N19/132 ,  H04N19/176

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：US12003774B2

公开(公告)日：2024-06-04

申请号：US18198382

申请日：2023-05-17

Applicant: LG Electronics Inc.

Inventor： Moonmo Koo ,  Seunghwan Kim ,  Jaehyun Lim

IPC: G06V10/00 ,  H04N19/11 ,  H04N19/124 ,  H04N19/132 ,  H04N19/159 ,  H04N19/176 ,  H04N19/18 ,  H04N19/61

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

Abstract: An image decoding method according to the present document 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, on the basis of an inverse primary transform for the modified transform coefficients, a restoration picture based on residual samples for the target block, wherein the modified transform coefficients derived according to the inverse RST are two-dimensionally arranged according to the order of a row priority direction or a column priority direction according to an intra prediction mode to be applied to the target block.

公开(公告)号：US12003773B2

公开(公告)日：2024-06-04

申请号：US18086422

申请日：2022-12-21

Applicant: LG ELECTRONICS INC.

Inventor： Moonmo Koo ,  Seunghwan Kim ,  Jaehyun Lim

IPC: H04N11/02 ,  H04N19/105 ,  H04N19/122 ,  H04N19/127 ,  H04N19/132 ,  H04N19/159 ,  H04N19/169 ,  H04N19/176 ,  H04N19/18 ,  H04N19/186 ,  H04N19/61

CPC classification number: H04N19/61 ,  H04N19/105 ,  H04N19/122 ,  H04N19/127 ,  H04N19/132 ,  H04N19/159 ,  H04N19/176 ,  H04N19/18 ,  H04N19/186 ,  H04N19/1883

Abstract: A video decoding method according to the present document comprises a step of deriving a modified transform coefficient, and the step of deriving the transform coefficient may comprise the steps of: determining whether an LFNST can be applied to the height and width of a current block on the basis of the tree type and color format of the current block; parsing an LFNST index if the LFNST can be applied; and deriving the modified transform coefficient on the basis of the LFNST index and an LFNST matrix.

公开(公告)号：US11997315B2

公开(公告)日：2024-05-28

申请号：US18100277

申请日：2023-01-23

Applicant: LG ELECTRONICS INC.

Inventor： Moonmo Koo ,  Seunghwan Kim ,  Jaehyun Lim

IPC: H04N19/60 ,  H04N19/122 ,  H04N19/124 ,  H04N19/132 ,  H04N19/176 ,  H04N19/18 ,  H04N19/70

CPC classification number: H04N19/60 ,  H04N19/122 ,  H04N19/124 ,  H04N19/132 ,  H04N19/176 ,  H04N19/18 ,  H04N19/70

Abstract: An image decoding method according to the present document may comprise the steps of: deriving a first variable indicating whether there is a valid coefficient in a region excluding a DC region from a current block; deriving a second variable indicating whether there is a valid coefficient in a second region excluding a first region formed at the upper left end of the current block; when the first variable indicates that the valid coefficient exists in the region excluding the DC region, and the second variable indicates that the valid coefficient does not exist in the second region, parsing an LFNST index from the bitstream; and applying an LFNST matrix derived on the basis of the LFNST index to transform coefficients in the first region, to derive the modified transform coefficients.