公开(公告)号：US11350130B2

公开(公告)日：2022-05-31

申请号：US17047849

申请日：2019-04-17

Applicant: LG Electronics Inc.

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

IPC: H04N19/00 ,  H04N19/61 ,  H04N19/159 ,  H04N19/176 ,  H04N19/625

Abstract: The present invention provides a method for reconstructing a video signal by using an approximation transform on the basis of a preprocessing/postprocessing matrix, the method comprising: obtaining a transform index of a current block from a video signal, wherein the transform index corresponds to any one of a plurality of transform combinations including at least one of DST7, DCT8, DST6, or flipped DST7, and a transform combination includes a horizontal transform and a vertical transform; deriving a primary transform for horizontal/vertical directions corresponding to the transform index; performing an inverse primary approximation transform by using the primary transform for the horizontal/vertical directions, wherein the inverse primary approximation transform is generated by multiplying the primary transform for the horizontal/vertical directions by a preprocessing matrix and a postprocessing matrix; and reconstructing the video signal by using the inverse primary approximation-transformed current block.

公开(公告)号：US11336920B2

公开(公告)日：2022-05-17

申请号：US17209854

申请日：2021-03-23

Applicant: LG ELECTRONICS INC.

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

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

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：US20220078434A1

公开(公告)日：2022-03-10

申请号：US17526940

申请日：2021-11-15

Applicant: LG ELECTRONICS INC.

Inventor： Mehdi Salehifar ,  Seunghwan Kim

IPC: H04N19/132 ,  H04N19/159 ,  H04N19/105 ,  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：US20210203969A1

公开(公告)日：2021-07-01

申请号：US17138722

申请日：2020-12-30

Applicant: LG ELECTRONICS INC.

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

IPC: H04N19/44 ,  H04N19/61 ,  H04N19/132 ,  H04N19/159 ,  H04N19/176

Abstract: Disclosed is a method for decoding a video signal, including: generating a dequantized transform block by performing dequantization for a current block; acquiring an intra prediction mode of the current block; determining a secondary transform set applied to the current block among a plurality of secondary transform sets based on the intra prediction mode; deriving a transform kernel applied to the current block in the determined secondary transform set; and performing secondary transform for a top left specific area of the dequantized transform block by using the derived transform kernel, in which the plurality of secondary transform sets may include at least one mixed secondary transform set.

公开(公告)号：US11012702B2

公开(公告)日：2021-05-18

申请号：US16898117

申请日：2020-06-10

Applicant: LG ELECTRONICS INC.

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

IPC: 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：US20210099704A1

公开(公告)日：2021-04-01

申请号：US17117785

申请日：2020-12-10

Applicant: LG Electronics Inc.

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

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

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：US12273528B2

公开(公告)日：2025-04-08

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

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：US12244812B2

公开(公告)日：2025-03-04

申请号：US17910493

申请日：2021-03-23

Applicant: LG ELECTRONICS INC.

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

IPC: H04N19/132 ,  H04N19/176 ,  H04N19/18 ,  H04N19/46 ,  H04N19/96

Abstract: An image decoding method according to the present document may comprise a step for deriving modified transform coefficients, wherein the step for deriving modified transform coefficients may comprise the steps of: determining whether the tree type of the current block is a single tree; parsing an LFNST index when the tree type is the single type, the LFNST index being parsed on the basis of a transform coefficient coding flag value for a luma component of the current block, or on the basis of whether an ISP mode is applicable to the luma component; and deriving the modified transform coefficients by applying an LFNST kernel derived on the basis of the LFNST index.

公开(公告)号：US20250024030A1

公开(公告)日：2025-01-16

申请号：US18899842

申请日：2024-09-27

Applicant: LG ELECTRONICS INC.

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

IPC: H04N19/11 ,  H04N19/176 ,  H04N19/61

Abstract: Embodiments of the present invention provide a method and apparatus for processing a video signal. A method for decoding an image signal according to an embodiment of the present invention comprises the steps of: for a current block having a width and a height different from each other, determining a modified intra prediction mode from an intra prediction mode, on the basis of a ratio between the width and the height of the current block and the intra prediction mode; determining an inverse non-separable transform set on the basis of the modified intra prediction mode; and applying an inverse non-separable transform matrix selected from the inverse non-separable transform set with respect to the top-left region of the current block, which is determined according to the width and the height of the current block.

公开(公告)号：US12192524B2

公开(公告)日：2025-01-07

申请号：US18231662

申请日：2023-08-08

Applicant: LG Electronics Inc.

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

IPC: H04N19/00 ,  H04N19/129 ,  H04N19/176 ,  H04N19/625 ,  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.