ARITHMETIC DECODING DEVICE, ARITHMETIC CODING DEVICE, IMAGE DECODING DEVICE AND IMAGE CODING DEVICE

摘要

In the present invention, a coefficient presence/absence flag decoding unit (124) is provided with a quantization residual information decoding unit (111) that reduces the amount of processing related to the coding and decoding of transformation coefficients. The coefficient presence/absence flag decoding unit (124) divides a target frequency region or target pixel region into sub-blocks and derives different context indices for transformation coefficients obtained by a transformation skip or transformation quantization bypass for the pixel region and transformation coefficients obtained by a frequency transformation for each frequency component.