公开(公告)号：US20230164332A1

公开(公告)日：2023-05-25

申请号：US18100781

申请日：2023-01-24

Applicant: LG ELECTRONICS INC.

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

IPC: H04N19/18 ,  H04N19/91 ,  H04N19/176 ,  H04N19/60 ,  H04N19/46 ,  H04N19/184

CPC classification number: H04N19/18 ,  H04N19/91 ,  H04N19/176 ,  H04N19/60 ,  H04N19/46 ,  H04N19/184

Abstract: An image information decoding method performed by means of a decoding device according to the present invention comprises the steps of: decoding a non-separable secondary transform (NSST) index from a bitstream if NSST is applied to a target block; decoding information relating to transform coefficients with respect to the target block from the bitstream on the basis of the decoded NSST index; and deriving the transform coefficients with respect to the target block on the basis of the decoded information relating to the transform coefficients, wherein the NSST index is decoded prior to the information relating to the transform coefficients with respect to the target block.

公开(公告)号：US20230164326A1

公开(公告)日：2023-05-25

申请号：US18094732

申请日：2023-01-09

Applicant: LG Electronics Inc.

Inventor： Mehdi SALEHIFAR ,  Seunghwan KIM

IPC: H04N19/159 ,  H04N19/132 ,  H04N19/176 ,  H04N19/593 ,  H04N19/70

CPC classification number: H04N19/159 ,  H04N19/132 ,  H04N19/176 ,  H04N19/593 ,  H04N19/70

Abstract: An image decoding method according to the present document can comprise the steps of: on the basis of first flag information indicating whether or not matrix-based intra prediction (MIP) can be applied to a current block, receiving second flag information indicating whether or not the MIP is used for the current block; receiving matrix-based intra prediction (MIP) mode information on the basis of the second flag information; generating intra prediction samples for the current block on the basis of the MIP mode information; and generating reconstructed samples for the current block on the basis of the intra prediction samples.

公开(公告)号：US20230128355A1

公开(公告)日：2023-04-27

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 ,  H04N19/96 ,  H04N19/18 ,  H04N19/176 ,  H04N19/46

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：US20230049623A1

公开(公告)日：2023-02-16

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：US20220385943A1

公开(公告)日：2022-12-01

申请号：US17767368

申请日：2020-10-08

Applicant: LG ELECTRONICS INC.

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

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

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：US20220377336A1

公开(公告)日：2022-11-24

申请号：US17864666

申请日：2022-07-14

Applicant: LG Electronics Inc.

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

IPC: 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：US20220217364A1

公开(公告)日：2022-07-07

申请号：US17707000

申请日：2022-03-29

Applicant: LG Electronics Inc.

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

IPC: H04N19/18 ,  H04N19/119 ,  H04N19/132 ,  H04N19/176 ,  H04N19/186 ,  H04N19/60 ,  H04N19/70 ,  H04N19/129 ,  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：US20220182651A1

公开(公告)日：2022-06-09

申请号：US17671946

申请日：2022-02-15

Applicant: LG ELECTRONICS INC.

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

IPC: H04N19/44 ,  H04N19/176 ,  H04N19/46 ,  H04N19/625 ,  H04N19/11 ,  H04N19/119 ,  H04N19/159 ,  H04N19/105

Abstract: Provided is a method for decoding a video signal based on a reduced transform, which includes: checking whether a transform skip is applied to a current block; obtaining a transform index indicating a transform kernel of the current block from the video signal when the transform skip is not applied to the current block; determining a region where a primary transform is applied to the current block based on the transform kernel indicated by the transform index and a size of the current block; and performing an inverse primary transform on the region to which the primary transform is applied by using the transform kernel indicated by the transform index.

公开(公告)号：US20220109875A1

公开(公告)日：2022-04-07

申请号：US17429518

申请日：2020-02-10

Applicant: LG Electronics Inc.

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

IPC: H04N19/60 ,  H04N19/176 ,  H04N19/105 ,  H04N19/46

Abstract: Embodiments in the present specification provide a method and device for processing video signal by using a sub-block unit transform. A method of decoding a video signal according to an embodiment of the present specification includes: a step for acquiring, from the video signal, information related to a transform of the current coding unit; and a step for applying an inverse transform, including a horizontal transform and a vertical transform, to a transform unit of the current coding unit on the basis of information related to the transform, wherein the information related to the transform includes: a first flag related to whether the current coding unit is divided into a plurality of sub-blocks; a second flag acquired on the basis of the first flag, and related to the respective sizes of the sub-blocks; a third flag acquired on the basis of the first flag, and related to dividing directions of the coding unit; and a fourth flag related to a sub-block in which a coded block flag (CBF) is present among the sub-blocks divided from the current coding unit on the basis of the second flag and the third flag.

公开(公告)号：US20210218996A1

公开(公告)日：2021-07-15

申请号：US17047849

申请日：2019-04-17

Applicant: LG Electronics Inc.

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

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

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.