公开(公告)号：US10924736B2

公开(公告)日：2021-02-16

申请号：US16898928

申请日：2020-06-11

Applicant: LG Electronics Inc.

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

IPC: H04N19/122 ,  H04N19/61 ,  H04N19/159 ,  H04N19/176

Abstract: Embodiments of the disclosure provide a method and apparatus for processing video signals. An image signal decoding method according to an embodiment of the disclosure comprises the steps of: determining, on the basis of the height and width of a current block, an input length and output length of a non-separable transform; determining a non-separable transform matrix corresponding to the input length and output length of the non-separable transform; and applying the non-separable transform matrix to the current block, wherein, when the height and width of the current block are 4 each, the input length and output length of the non-separable transform are determined to be 8 and 16 respectively.

公开(公告)号：US12262025B2

公开(公告)日：2025-03-25

申请号：US17963449

申请日：2022-10-11

Applicant: LG Electronics Inc.

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

IPC: H04N19/18 ,  H04N19/119 ,  H04N19/129 ,  H04N19/132 ,  H04N19/176 ,  H04N19/186 ,  H04N19/60 ,  H04N19/70 ,  H04N19/96

Abstract: An image decoding method according to the present document comprises: a residual coding step for parsing residual information received in a residual coding level and arranging transform coefficients for a current block according to a predetermined scanning order; a step for deriving residual samples by applying at least one of LFNST or MTS to the transform coefficients; and a step for generating a reconstructed picture on the basis of the residual samples, wherein the LFNST is performed on the basis of an LFNST index indicating an LFNST kernel, the MTS is performed on the basis of an MTS index indicating an MTS kernel, the LFNST index and the MTS index are signaled in a coding unit level, and the MTS index is signaled immediately after the signaling of the LFNST index.

公开(公告)号：US12250393B2

公开(公告)日：2025-03-11

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

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：US12143585B2

公开(公告)日：2024-11-12

申请号：US17344410

申请日：2021-06-10

Applicant: LG Electronics Inc.

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

IPC: H04N19/122 ,  H04N19/11 ,  H04N19/132 ,  H04N19/159 ,  H04N19/176 ,  H04N19/18 ,  H04N19/46

Abstract: A video decoding method according to the present document comprises the steps of: deriving transform coefficients by performing de-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) 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 an inverse RST using a transform kernel matrix is performed on transform coefficients of an upper-left 4×4 region of an 8×8 region of the target block, and modified transform coefficients of the upper-left 4×4 region, an upper-right 4×4 region, and a lower-left 4×4 region of the 8×8 region are derived through the inverse RST.

公开(公告)号：US12058374B2

公开(公告)日：2024-08-06

申请号：US17962077

申请日：2022-10-07

Applicant: LG Electronics Inc.

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

IPC: H04N11/02 ,  H04N19/132 ,  H04N19/159 ,  H04N19/176 ,  H04N19/18 ,  H04N19/61

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

Abstract: A video transform method includes: receiving a quantized transform coefficient for a target block and a transform index for a non-separated secondary transform; inverse-quantizing the quantized transform coefficient; deriving an input transform coefficient size indicating the length of the inverse-quantized transform coefficient to which the non-separated secondary transform has been applied, an output transform coefficient size indicating the length of a modified transform coefficient to which the non-separated secondary transform has been applied, and a transform set mapped to the intra mode of the target block, when the transform index does not indicate that the non-separated secondary transform is not performed; and deriving the modified transform coefficient on the basis of a matrix operation on a transform kernel matrix in the transform set indicated by the transform index, and a transform coefficient list corresponding to the input transform coefficient size.

公开(公告)号：US12052421B2

公开(公告)日：2024-07-30

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 ,  H04N19/176 ,  H04N19/18 ,  H04N19/186 ,  H04N19/46

CPC classification number: H04N19/132 ,  H04N19/176 ,  H04N19/18 ,  H04N19/186 ,  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.

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.