US 12,256,102 B2
Image coding using transform index
Junghak Nam, Seoul (KR); Jaehyun Lim, Seoul (KR); Moonmo Koo, Seoul (KR); and Seunghwan Kim, Seoul (KR)
Assigned to LG Electronics Inc., Seoul (KR)
Filed by LG Electronics Inc., Seoul (KR)
Filed on Oct. 19, 2023, as Appl. No. 18/381,790.
Application 18/381,790 is a continuation of application No. 17/503,792, filed on Oct. 18, 2021, granted, now 11,831,918.
Application 17/503,792 is a continuation of application No. PCT/KR2020/005079, filed on Apr. 16, 2020.
Claims priority of provisional application 62/834,950, filed on Apr. 16, 2019.
Prior Publication US 2024/0048766 A1, Feb. 8, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. H04N 19/60 (2014.01); H04N 19/122 (2014.01); H04N 19/159 (2014.01); H04N 19/176 (2014.01); H04N 19/18 (2014.01)
CPC H04N 19/60 (2014.11) [H04N 19/122 (2014.11); H04N 19/159 (2014.11); H04N 19/176 (2014.11); H04N 19/18 (2014.11)] 4 Claims
OG exemplary drawing
 
1. An image decoding method performed by a decoding apparatus, the method comprising:
receiving image information including prediction mode information and information on transform coefficients for a current block;
deriving prediction samples of the current block by performing an intra prediction based on the prediction mode information;
generating residual samples of the current block based on the information on the transform coefficients; and
generating reconstructed samples for the current block based on the prediction samples and the residual samples,
wherein the image information includes intra prediction type information for the current block,
wherein based on a tree type of the current block being single tree or dual tree luma, the intra prediction type information includes a matrix based intra prediction (MIP) flag representing whether MIP is applied to the current block,
wherein in response to the MIP being applied to the current block as the value of the MIP flag is equal to 1, the prediction samples of the current block are derived by reducing neighboring reference samples of the current block, performing a matrix-multiplication on the reduced neighboring reference samples, and adding an offset to values on which the matrix-multiplication is performed,
wherein a size of the matrix used for the matrix-multiplication is determined in response to a size of the current block,
wherein the size of the matrix is 16×8 in response to the size of the current block being 8×8,
wherein based on an intra sub-partitions (ISP) being not applied to the current block, a width and height of the current block being more than or equal to 4, the prediction mode information representing an intra mode and the MIP flag representing that the MIP is not applied, the image information includes low frequency non-separable transform (LFNST) index information related to one of transform kernels in an LFNST transform set for the current block,
wherein a parsing order of the MIP flag always precedes a parsing order of the LFNST index information,
wherein based on the MIP flag representing that the MIP is applied, the LFNST index information is not present and a value of the LFNST index information is derived as 0, and
wherein the residual samples are generated based on the information on the transform coefficients by using the LFNST index information.