公开(公告)号：US20230379473A1

公开(公告)日：2023-11-23

申请号：US18360351

申请日：2023-07-27

Applicant: LG Electronics Inc.

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

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

CPC classification number: H04N19/132 ,  H04N19/159 ,  H04N19/176 ,  H04N19/18 ,  H04N19/186

Abstract: A method for image decoding, 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; 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; and determining an LFNST set including LFNST matrices on the basis of the updated intra prediction mode, wherein the updated intra prediction mode is derived as an intra prediction mode corresponding to a specific position in the luma block, and the specific position is set on the basis of a color format of the chroma block.

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：US20230076486A1

公开(公告)日：2023-03-09

申请号：US17974971

申请日：2022-10-27

Applicant: LG ELECTRONICS INC.

Inventor： Moonmo KOO ,  Jaehyun LIM ,  Seunghwan KIM

IPC: H04N19/60 ,  H04N19/12 ,  H04N19/132 ,  H04N19/172 ,  H04N19/176 ,  H04N19/18

Abstract: An image decoding method according to the present document comprises a step of deriving a residual sample for a current block on the basis of a transform coefficient, wherein the step of deriving the transform coefficient can comprise the steps of: determining whether a sub block transform for performing a transform by dividing a coding unit is applied to the current block; determining whether a multiple transform selection (MTS), for which a plurality of transform kernels are used, is applied to the current block; and setting the size of a transform block to which the transform is to be applied, on the basis of whether the sub block transform is applied to the current block and whether the multiple transform selection is applied to the current block.

公开(公告)号：US20230054294A1

公开(公告)日：2023-02-23

申请号：US17791478

申请日：2021-01-08

Applicant: LG ELECTRONICS INC.

Inventor： Moonmo KOO ,  Seunghwan KIM ,  Jaehyun LIM

IPC: H04N19/132 ,  H04N19/96 ,  H04N19/18 ,  H04N19/186 ,  H04N19/176 ,  H04N19/46

Abstract: An image decoding method according to the present document may comprise a step for deriving corrected transform coefficients, wherein the step for deriving corrected transform coefficients may comprise the steps of: determining whether the tree type of the current block is a single tree; deriving a first variable and a second variable for a luma component of the current block and not deriving the first and second variables for a chroma component of the current block if the tree type is the first tree; parsing an LFNST index on the basis of the first variable and the second variable; and deriving the corrected 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：US20230047743A1

公开(公告)日：2023-02-16

申请号：US17963446

申请日：2022-10-11

Applicant: LG Electronics Inc.

Inventor： Junghak NAM ,  Jaehyun LIM ,  Moonmo KOO ,  Seunghwan KIM

IPC: H04N19/593 ,  H04N19/119 ,  H04N19/159 ,  H04N19/176 ,  H04N19/18 ,  H04N19/61 ,  H04N19/70

Abstract: An image coding method according to the present document comprises the steps of: deriving transform coefficients for a current block on the basis of residual-related information; and generating residual samples of the current block on the basis of the transform coefficients. The residual-related information comprises low frequency non-separable transform (LFNST) index information, showing information relating to non-separable transform for low-frequency transform coefficients of the current block, on the basis of a matrix-based intra-prediction (MIP) flag showing whether or not MIP is applied to the current block. The residual samples are generated from the transform coefficients on the basis of the LFNST index information.

公开(公告)号：US20230035863A1

公开(公告)日：2023-02-02

申请号：US17947047

申请日：2022-09-16

Applicant: LG ELECTRONICS INC.

Inventor： Moonmo KOO ,  Jaehyun LIM ,  Seunghwan KIM

IPC: H04N19/61 ,  H04N19/119 ,  H04N19/124 ,  H04N19/132 ,  H04N19/159 ,  H04N19/176 ,  H04N19/18 ,  H04N19/46

Abstract: An image decoding method according to the present document comprises the steps of: receiving a quantized transform coefficient for a target block and a transform index for non-separable quadratic transform; deriving transform coefficients by inversely quantizing the quantized transform coefficient; deriving corrected transform coefficients on the basis of a transform kernel matrix in a predetermined transform set indicated by the transform index; and deriving residual samples for the target block on the basis of inverse linear transform for the corrected transform coefficients, wherein when the target block is divided into a predetermined number of sub-blocks and is coded by intra prediction, the corrected transform coefficients are derived in units of the sub-blocks, and the transform index is received for the target block.

公开(公告)号：US20230035396A1

公开(公告)日：2023-02-02

申请号：US17957916

申请日：2022-09-30

Applicant: LG Electronics Inc.

Inventor： Hyeongmoon JANG ,  Eunyong SON ,  Moonmo KOO ,  Seungwook PARK ,  Yongjoon JEON

IPC: H04N19/56 ,  H04N19/176 ,  H04N19/124 ,  H04N19/503 ,  H04N19/105 ,  H04N19/70 ,  H04N19/182 ,  H04N19/513 ,  H04N19/66

Abstract: A video decoding method performed by a decoding apparatus includes the steps of: deriving control points (CP) for a current block; acquiring movement vectors for the CPs; deriving a sample unit movement vector in the current block on the basis of the acquired movement vectors; and deriving a prediction sample for the current block on the basis of the sample unit movement vector. According to the present invention, it is possible to effectively perform, through sample unit motion vectors, inter-prediction not only in a case where an image in the current block is plane-shifted but also in a case where there are various image distortions.

公开(公告)号：US20220394258A1

公开(公告)日：2022-12-08

申请号：US17776110

申请日：2020-11-13

Applicant: LG ELECTRONICS INC.

Inventor： Moonmo KOO ,  Seunghwan KIM ,  Jaehyun LIM

IPC: H04N19/12 ,  H04N19/136 ,  H04N19/61 ,  H04N19/176 ,  H04N19/18

Abstract: An image decoding method according to the present document comprises the step of deriving modified transform coefficients, wherein the step of deriving the modified transform coefficients comprises the step of parsing an LFNST index on the basis of a variable indicating whether an ISP is applied to a current block or whether an effective coefficient is present in a DC component of the current block, according to the tree type of the current block, wherein the variable may be derived on the basis of an individual transform skip flag value for a color component of the current block.

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.