US 12,113,978 B2
Encoder, decoder, encoding method, and decoding method
Masato Ohkawa, Toyama (JP); Hideo Saitou, Ishikawa (JP); Tadamasa Toma, Osaka (JP); Takahiro Nishi, Nara (JP); Kiyofumi Abe, Osaka (JP); and Ryuichi Kanoh, Osaka (JP)
Assigned to PANASONIC INTELLECTUAL PROPERTY CORPORATION OF AMERICA, Torrance, CA (US)
Filed by Panasonic Intellectual Property Corporation of America, Torrance, CA (US)
Filed on Jun. 27, 2023, as Appl. No. 18/214,653.
Application 18/214,653 is a continuation of application No. 16/911,810, filed on Jun. 25, 2020, granted, now 11,729,386.
Application 16/911,810 is a continuation of application No. PCT/JP2018/046694, filed on Dec. 19, 2018.
Claims priority of provisional application 62/611,242, filed on Dec. 28, 2017.
Claims priority of provisional application 62/611,259, filed on Dec. 28, 2017.
Prior Publication US 2023/0345000 A1, Oct. 26, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. H04N 19/12 (2014.01); H04N 19/124 (2014.01); H04N 19/176 (2014.01); H04N 19/625 (2014.01)
CPC H04N 19/12 (2014.11) [H04N 19/124 (2014.11); H04N 19/176 (2014.11); H04N 19/625 (2014.11)] 4 Claims
OG exemplary drawing
 
1. An encoder comprising:
circuitry; and
memory,
wherein the circuitry, using the memory, performs:
generating first transform coefficients by performing a horizontal transform and a vertical transform on residuals using a horizontal transform basis and a vertical transform basis, respectively, when it is determined that the horizontal transform and the vertical transform are to be performed for the current block;
generating second transform coefficients by performing a non-separable transform on the first transform coefficients when it is determined that the non-separable transform is to be performed for the current block; and
encoding a signal which indicates whether the non-separable transform is performed or not,
wherein (i) when it is determined that a selection of a transform basis based on a size of the current block is performed for the current block, the circuitry performs, before performing the horizontal transform and the vertical transform:
selecting a first transform basis, as the horizontal transform basis, from among transform basis candidates when a horizontal size of the current block is a first horizontal size that is greater than a threshold size;
selecting a second transform basis, as the horizontal transform basis, from among the transform basis candidates when the horizontal size of the current block is a second horizontal size that is smaller than or equal to the threshold size, the second transform basis being different from the first transform basis;
selecting the first transform basis, as the vertical transform basis, from among the transform basis candidates when a vertical size of the current block is a first vertical size that is greater than the threshold size; and
selecting the second transform basis, as the vertical transform basis, from among the transform basis candidates when the vertical size of the current block is a second vertical size that is smaller than or equal to the threshold size, and
wherein (ii) when the non-separable transform is performed for the current block, a basic transform basis is selected as the vertical transform basis and the horizontal transform basis.