公开(公告)号：US12284356B2

公开(公告)日：2025-04-22

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

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：US12273526B2

公开(公告)日：2025-04-08

申请号：US17767380

申请日：2020-10-08

Applicant: LG ELECTRONICS INC.

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

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

Abstract: An image decoding method according to the present document may be characterized by including the steps of: determining whether to parse an MTS index for applying MTS to the current block; and applying the MTS to the current block on the basis of the MTS index to derive residual samples for the current block, wherein whether to parse the MTS index is determined on the basis of a flag value indicating whether a transform coefficient for a luma component of the current block is present, and the MTS index is not parsed when the flag value is 0.

公开(公告)号：US12256103B2

公开(公告)日：2025-03-18

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

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：US12244862B2

公开(公告)日：2025-03-04

申请号：US17767368

申请日：2020-10-08

Applicant: LG ELECTRONICS INC.

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

IPC: H04N19/176 ,  H04N19/12 ,  H04N19/124 ,  H04N19/132 ,  H04N19/18 ,  H04N19/186 ,  H04N19/61 ,  H04N19/70

Abstract: An image decoding method, according to the present document, comprises the steps of: deriving residual samples by applying at least one among LFNST or MTS to a transform coefficient; and generating a reconstructed picture on the basis of the residual samples, wherein the LFNST is carried out on the basis of a LFNST index indicating a LFNST kernel, the MTS is carried out on the basis of a MTS index indicating a MTS kernel, the MTS index is parsed on the basis that the color index of the current block is a luma component, and the LFNST index may be parsed regardless of the color index of the current block.

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：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：US12010336B2

公开(公告)日：2024-06-11

申请号：US17419869

申请日：2019-12-31

Applicant: LG ELECTRONICS INC.

Inventor： Seethal Paluri ,  Seunghwan Kim ,  Mehdi Salehifar

IPC: H04N19/52 ,  H04N19/137 ,  H04N19/176 ,  H04N19/70

CPC classification number: H04N19/52 ,  H04N19/137 ,  H04N19/176 ,  H04N19/70

Abstract: A method and device for processing a video signal are disclosed. More specifically, a method of processing a video signal based on inter prediction may comprise: deriving a motion vector predictor based on motion information of a neighboring block of a current block; deriving a motion vector difference of the current block based on layer information and index information; deriving a motion vector of the current block based on the motion vector predictor and the motion vector difference; generating a prediction block of the current block based on the motion vector of the current block; and generating a reconstructed block of the current block based on the prediction block and a residual block of the current block, wherein the layer information includes at least one syntax element indicating a layer group to which the current layer belongs.

公开(公告)号：US11968398B2

公开(公告)日：2024-04-23

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