公开(公告)号：US11245894B2

公开(公告)日：2022-02-08

申请号：US16897681

申请日：2020-06-10

Applicant: LG Electronics Inc.

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

IPC: H04N19/12 ,  H04N19/593 ,  H04N19/11 ,  H04N19/176 ,  H04N19/61 ,  H04N19/70

Abstract: Embodiments of the disclosure provide a method and apparatus for processing a video signal. Particularly, a method for decoding a video signal according to an embodiment of the disclosure may include: determining, among predefined secondary transform sets based on intra-prediction modes of a current block, a secondary transform set applied to the current block; obtaining a first syntax element indicating a secondary transform matrix applied to the current block in the determined secondary transform set; deriving a secondary inverse-transformed block by performing a secondary inverse transform on a left top region of the current block by using the secondary transform matrix specified by the first syntax element; and deriving a residual block of the current block by performing a primary inverse transform on the secondary inverse-transformed block using a primary transform matrix of the current block.

公开(公告)号：US20200322611A1

公开(公告)日：2020-10-08

申请号：US16904985

申请日：2020-06-18

Applicant: LG Electronics Inc.

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

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

Abstract: A method for decoding an image by a decoding device according to the present invention comprises the steps of: deriving, from a bit stream, transform coefficients of a block to be decoded; deriving residual samples of the block to be decoded, on the basis of a selective transform of the transform coefficients; and generating a reconstructed picture on the basis of the residual samples of the block to be decoded and prediction samples of the block to be decoded, wherein the selective transform is performed on the basis of a modified transform matrix, the modified transform matrix comprises a matrix including a modified basis vector, and the modified basis vector contains a certain number of elements selected from N elements.

公开(公告)号：US20200304791A1

公开(公告)日：2020-09-24

申请号：US16898928

申请日：2020-06-11

Applicant: LG Electronics Inc.

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

IPC: H04N19/122 ,  H04N19/176 ,  H04N19/159 ,  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：US20190387241A1

公开(公告)日：2019-12-19

申请号：US16429956

申请日：2019-06-03

Applicant: LG ELECTRONICS INC.

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

IPC: H04N19/44 ,  H04N19/625 ,  H04N19/46 ,  H04N19/176

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.