PICTURE CODING METHOD, PICTURE DECODING METHOD, PICTURE CODING APPARATUS, PICTURE DECODING APPARATUS, AND PROGRAM THEREOF

The picture decoding method according to the present invention is a decoding method for decoding coded pictures by inverse quantization and inverse orthogonal transformation, in which a quantization matrix which defines a scaling ratio of a quantization step for each component is multiplied by a multiplier, which is a coefficient for frequency transformation or a quantization step, and also, a result of the multiplication is multiplied by a quantized value, as a process of inverse quantization.