US 12,088,831 B2
Method, apparatus and system for encoding and decoding a block of video samples
Christopher James Rosewarne, Concord (AU); and Iftekhar Ahmed, Lane Cove North (AU)
Assigned to Canon Kabushiki Kaisha, Tokyo (JP)
Appl. No. 17/642,093
Filed by Canon Kabushiki Kaisha, Tokyo (JP)
PCT Filed Aug. 4, 2020, PCT No. PCT/AU2020/050798
§ 371(c)(1), (2) Date Mar. 10, 2022,
PCT Pub. No. WO2021/051155, PCT Pub. Date Mar. 25, 2021.
Claims priority of application No. 2019232801 (AU), filed on Sep. 17, 2019.
Prior Publication US 2024/0073432 A1, Feb. 29, 2024
Int. Cl. H04N 19/186 (2014.01); H04N 19/122 (2014.01); H04N 19/132 (2014.01); H04N 19/159 (2014.01); H04N 19/169 (2014.01); H04N 19/176 (2014.01); H04N 19/18 (2014.01); H04N 19/46 (2014.01); H04N 19/61 (2014.01)
CPC H04N 19/186 (2014.11) [H04N 19/122 (2014.11); H04N 19/132 (2014.11); H04N 19/159 (2014.11); H04N 19/176 (2014.11); H04N 19/18 (2014.11); H04N 19/1883 (2014.11); H04N 19/46 (2014.11); H04N 19/61 (2014.11)] 14 Claims
OG exemplary drawing
 
1. A method of decoding a coding unit in a coding tree unit of an image from a bitstream, the coding unit having a luma channel and at least one chroma channel, the method comprising:
determining the coding unit having the luma channel and the at least one chroma channel according to one or more split flags for the coding tree unit;
decoding, from the bitstream, an index for selecting a non-separable transform kernel for the luma channel;
selecting the non-separable transform kernel according to the index;
decoding, from the bitstream, coefficients of the luma channel and coefficients of the at least one chroma channel;
determining at least whether a non-separable transform is performed on the coefficients of the at least one chroma channel;
performing, by applying the selected non-separable transform kernel, the non-separable transform on the coefficients of the luma channel to derive non-separably transformed coefficients of the luma channel, and not performing the non-separable transform on the coefficients of the at least one chroma channel, in a case where it is determined that the non-separable transform is not performed on the coefficients of the at least one chroma channel; and
decoding the coding unit by performing a separable transform on the non-separably transformed coefficients of the luma channel and on the coefficients of the at least one chroma channel.