US 12,170,794 B2
Image encoding device, image encoding method and storage medium, image decoding device, and image decoding method and storage medium
Masato Shima, Tokyo (JP)
Assigned to Canon Kabushiki Kaisha, Tokyo (JP)
Filed by CANON KABUSHIKI KAISHA, Tokyo (JP)
Filed on Sep. 12, 2022, as Appl. No. 17/931,450.
Application 17/931,450 is a continuation of application No. PCT/JP2021/006754, filed on Feb. 24, 2021.
Claims priority of application No. 2020-048201 (JP), filed on Mar. 18, 2020.
Prior Publication US 2023/0007311 A1, Jan. 5, 2023
Int. Cl. H04N 19/89 (2014.01); H04N 19/124 (2014.01); H04N 19/18 (2014.01); H04N 19/60 (2014.01)
CPC H04N 19/89 (2014.11) [H04N 19/124 (2014.11); H04N 19/18 (2014.11); H04N 19/60 (2014.11)] 12 Claims
OG exemplary drawing
 
1. An image encoding device comprising:
a prediction unit configured to generate prediction errors being a difference between (a) a predicted image obtained by prediction processing for a sub-block in an input image and (b) the sub-block;
a first transform unit configured to generate first transform coefficients by performing orthogonal transform on the prediction errors;
a second transform unit configured to generate second transform coefficients by performing Low Frequency Non-Separable Transform (LFNST) processing on the first transform coefficients;
a quantization unit configured to generate quantization coefficients by performing quantization processing on the second transform coefficients; and
an encoding unit configured to encode the quantization coefficients,
wherein the encoding unit encodes information indicating whether a range of possible values at least taken by the second transform coefficients is to be (a) a first range determined based on a bit depth or (b) a second range which is a fixed range and which is not dependent on the bit depth,
wherein, in a case where the information indicates that the range of possible values at least taken by the second transform coefficients is to be the first range determined based on the bit depth, a range of possible values taken by Block-based Delta Pulse Code Modulation (BDPCM) process is the first range determined based on the bit depth, and
wherein, in a case where the information indicates that the range of possible values at least taken by the second transform coefficients is to be the second range which is the fixed range and which is not dependent on the bit depth, the range of possible values taken by the BDPCM process is the second range.