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

摘要

PROBLEM TO BE SOLVED: To reduce a processing amount related to coding and decoding of transform coefficients.SOLUTION: A coefficient presence/absence flag decoding unit 124 of a quantized residual information decoding unit 111 divides a target frequency domain into sub-blocks, derives a value based on a position on the frequency domain or a fixed predetermined value for a transform coefficient in a sub-block including the last coefficient as a context index, and derives a context index for a transform coefficient in a sub-block not including the last coefficient by referring to a decoded non-zero transform coefficient.