公开(公告)号：US20230388547A1

公开(公告)日：2023-11-30

申请号：US18231662

申请日：2023-08-08

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：US20230328288A1

公开(公告)日：2023-10-12

申请号：US18327512

申请日：2023-06-01

Applicant: LG Electronics Inc.

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

IPC: H04N19/625 ,  H04N19/132 ,  H04N19/176 ,  H04N19/70

CPC classification number: H04N19/625 ,  H04N19/70 ,  H04N19/176 ,  H04N19/132

Abstract: A method for decoding a video signal based on reduced transform includes the steps of: obtaining, from the video signal, a transform index indicating transform kernels applied to horizontal and vertical directions of a current block; determining a region in which a transform is applied to the current block based on the transform kernels indicated by the transform index and a size of the current block; deriving, as zero, coefficients of a remaining region other than the region to which the transform is applied within the current block; and performing an inverse transform on the region to which the transform is applied using the transform kernels indicated by the transform index.

公开(公告)号：US20230308670A1

公开(公告)日：2023-09-28

申请号：US18143950

申请日：2023-05-05

Applicant: LG ELECTRONICS INC.

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

IPC: H04N19/44 ,  H04N19/159 ,  H04N19/176 ,  H04N19/625 ,  H04N19/70

CPC classification number: H04N19/44 ,  H04N19/159 ,  H04N19/176 ,  H04N19/625 ,  H04N19/70

Abstract: A method and a device for processing a video signal are disclosed. In particular, a method for decoding a video signal includes parsing a first syntax element indicating a primary transform kernel applied to a primary transform of a current block; determining whether a secondary transform is applicable to the current block based on the first syntax element; if the secondary transform is applicable to the current block, parsing a second syntax element indicating a secondary transform kernel applied to a secondary transform of the current block; deriving a secondary inverse-transformed block, by performing a secondary inverse-transform for a top-left specific region of the current block using a secondary transform kernel indicated by the second syntax element; and deriving a residual block of the current block, by performing a primary inverse-transform for the secondary inverse-transformed block using a primary transform kernel indicated by the first syntax element.

公开(公告)号：US20230171426A1

公开(公告)日：2023-06-01

申请号：US18073151

申请日：2022-12-01

Applicant: LG ELECTRONICS INC.

Inventor： Moonmo KOO ,  Jaehyun Lim ,  Seunghwan Kim

IPC: H04N19/593 ,  H04N19/11 ,  H04N19/136 ,  H04N19/159 ,  H04N19/176 ,  H04N19/196 ,  H04N19/61

CPC classification number: H04N19/593 ,  H04N19/11 ,  H04N19/136 ,  H04N19/159 ,  H04N19/176 ,  H04N19/197 ,  H04N19/61

Abstract: Embodiments in the present specification provide a video signal processing method and device. A method of processing a video signal according to an embodiment in the present specification comprises the steps of: acquiring an intra-prediction mode for a current block from the video signal; determining a modified intra-prediction mode from the intra-prediction mode for the current block on the basis of the width and height of and the intra-prediction mode for the current block; and applying a transform determined on the basis of the modified intra-prediction mode. The accuracy of prediction can be further improved by deriving a modified intra-prediction mode according to a wide-angle intra-prediction mode according to the shape of and an intra-prediction mode for a current block.

公开(公告)号：US20230164356A1

公开(公告)日：2023-05-25

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.

公开(公告)号：US20230164319A1

公开(公告)日：2023-05-25

申请号：US18097775

申请日：2023-01-17

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：US20230156223A1

公开(公告)日：2023-05-18

申请号：US18097625

申请日：2023-01-17

Applicant: LG Electronics Inc.

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

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

CPC classification number: H04N19/60 ,  H04N19/105 ,  H04N19/124 ,  H04N19/176 ,  H04N19/18 ,  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：US20230122409A1

公开(公告)日：2023-04-20

申请号：US18081297

申请日：2022-12-14

Applicant: LG Electronics Inc.

Inventor： Moonmo KOO ,  Seunghwan KIM ,  Jaehyun LIM

IPC: H04N19/61 ,  H04N19/176 ,  H04N19/18 ,  H04N19/186

Abstract: An image decoding method according to the present document comprises a step for deriving a modified transform coefficient, wherein the step for deriving the modified transform coefficient comprises a step for determining whether or not to parse an LFNST index on the basis of whether or not the width and height of a current block satisfy a condition about whether the LFNST can be applied, and whether or not the condition about whether the LFNST can be applied is satisfied is determined on the basis of a tree type and a color format of the current block and whether or not an ISP is applied to the current block.

公开(公告)号：US20230080150A1

公开(公告)日：2023-03-16

申请号：US17988611

申请日：2022-11-16

Applicant: LG Electronics Inc.

Inventor： Moonmo KOO ,  Hyeongmoon JANG ,  Seunghwan KIM ,  Jaehyun LIM

IPC: H04N19/132 ,  H04N19/159 ,  H04N19/176 ,  H04N19/18 ,  H04N19/186

Abstract: An image decoding method according to the present document may comprise the steps of: deriving an intra prediction mode of a chroma block as a cross-component linear model (CCLM) mode on the basis of intra prediction mode information; updating the intra prediction mode of the chroma block on the basis of an intra prediction mode of a luma block corresponding to the chroma block; when the chroma block is not square, remapping the updated intra prediction mode to a wide-angle intra prediction mode; and determining an LFNST set including LFNST matrices on the basis of the remapped intra prediction mode.

公开(公告)号：US20230053262A1

公开(公告)日：2023-02-16

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: 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.