公开(公告)号：US11558641B2

公开(公告)日：2023-01-17

申请号：US17503042

申请日：2021-10-15

Applicant: LG Electronics Inc.

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

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

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：US11516511B2

公开(公告)日：2022-11-29

申请号：US17591431

申请日：2022-02-02

Applicant: LG ELECTRONICS INC.

Inventor： Moonmo Koo ,  Jaehyun Lim ,  Seunghwan Kim

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

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：US11470324B2

公开(公告)日：2022-10-11

申请号：US17535090

申请日：2021-11-24

Applicant: LG Electronics Inc.

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

IPC: H04N19/132 ,  H04N19/105 ,  H04N19/176 ,  H04N19/18

Abstract: An image decoding method, according to the present document, may comprise the steps of: deriving transform coefficients for a current block on the basis of residual information; determining whether a significant coefficient is present in a second region excluding a first region in the top-left end of the current block; parsing a LFNST index from a bitstream if the significant coefficient is not present in the second region; deriving modified transform coefficients by applying a LFNST matrix, derived on the basis of the LFNST index, to transform coefficients of the first region; and deriving residual samples of the current block on the basis of an inverse primary transform of the modified transform coefficients.

公开(公告)号：US11470320B2

公开(公告)日：2022-10-11

申请号：US17501885

申请日：2021-10-14

Applicant: LG ELECTRONICS INC.

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

IPC: H04N19/124 ,  H04N19/132 ,  H04N19/159 ,  H04N19/176 ,  H04N19/18 ,  H04N19/186 ,  H04N19/46

Abstract: An image decoding method according to the present document comprises the steps of: deriving a quantized transform coefficient for a current block on the basis of BDPCM; deriving a transform coefficient by performing dequantization on the quantized transform coefficient; and deriving a residual sample on the basis of the transform coefficient, wherein, when the BDPCM is applied to the current block, inverse non-separable transform is not applied to the transform coefficient.

公开(公告)号：US11445189B2

公开(公告)日：2022-09-13

申请号：US17472137

申请日：2021-09-10

Applicant: LG ELECTRONICS INC.

Inventor： Ling Li ,  Jin Heo ,  Moonmo Koo ,  Jung Hak Nam

IPC: H04N19/119 ,  H04N19/159 ,  H04N19/176 ,  H04N19/186 ,  H04N19/593

Abstract: An image encoding/decoding method and apparatus are provided. An image decoding method according to the present disclosure may include determining whether a prediction mode of a current block is an intra prediction mode based on information on the prediction mode of the current block, determining whether intra sub-partitions (ISP) is available for the current block, when the prediction mode of the current block is an intra prediction mode, decoding an ISP application indicator indicating whether to apply ISP to the current block, when ISP is available for the current block, and generating a prediction block for the current block by applying ISP to the current block, upon determining that ISP applies to the current block based on the ISP application indicator.

公开(公告)号：US20220264105A1

公开(公告)日：2022-08-18

申请号：US17732126

申请日：2022-04-28

Applicant: LG Electronics Inc.

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

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

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：US20220217401A1

公开(公告)日：2022-07-07

申请号：US17700139

申请日：2022-03-21

Applicant: LG ELECTRONICS INC.

Inventor： Moonmo Koo ,  Seunghwan Kim ,  Jaehyun Lim

IPC: H04N19/61 ,  H04N19/18 ,  H04N19/176 ,  H04N19/132 ,  H04N19/122 ,  H04N19/186 ,  H04N19/169 ,  H04N19/105 ,  H04N19/159 ,  H04N19/127

Abstract: A video decoding method according to the present document comprises a step of deriving a modified transform coefficient, and the step of deriving the transform coefficient may comprise the steps of: determining whether an LFNST can be applied to the height and width of a current block on the basis of the tree type and color format of the current block; parsing an LFNST index if the LFNST can be applied; and deriving the modified transform coefficient on the basis of the LFNST index and an LFNST matrix.

公开(公告)号：US11368691B2

公开(公告)日：2022-06-21

申请号：US17043494

申请日：2019-03-29

Applicant: LG ELECTRONICS INC.

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

IPC: H04N19/122 ,  H04N19/14 ,  H04N19/176 ,  H04N19/625 ,  H04N19/105 ,  H04N19/513 ,  H04N19/51 ,  H04N19/103 ,  H04N19/70 ,  H04N19/423 ,  H04N19/55

Abstract: Reconstructing a video signal based on low-complexity DST7 design including obtaining a transform index of a current block from the video signal and deriving a transform combination corresponding to the transform index. The transform index corresponds to any one of a plurality of transform combinations including a combination of DST7 and/or DCT8, and the transform combination includes horizontal and vertical transforms that correspond to at least one of the DST7 or the DCT8. The reconstruction also includes performing an inverse transform in a vertical direction by using the DST7, performing an inverse transform in a horizontal direction by using the DCT8, and reconstructing the video signal by using the current block on which the inverse transform is performed. The DST7 includes Discrete Fourier Transform (DFT) and has a different type of DFT structure based on a size of the current block.

公开(公告)号：US11356686B2

公开(公告)日：2022-06-07

申请号：US17266407

申请日：2019-08-08

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：US20220159299A1

公开(公告)日：2022-05-19

申请号：US17591431

申请日：2022-02-02

Applicant: LG ELECTRONICS INC.

Inventor： Moonmo Koo ,  Jaehyun Lim ,  Seunghwan Kim

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

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.