摘要:
The picture decoding method according to the present invention is a decoding method for decoding coded pictures by inverse quantization (IQ1) 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 (IQ11), 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.
摘要:
The picture coding method according to the present invention is a picture coding method for coding a picture on a block-by-block basis through orthogonal transformation (Fig. 3, T) and quantization (Fig. 3, Q), and coding a quantization matrix (Fig. 2) that is used to derive quantization steps for frequencies of orthogonal transformation coefficients, the method comprising: calculating a difference value between each of frequency components included in the quantization matrix (Fig. 2) and a predetermined value corresponding to said each of the frequency components; and coding the difference value into a variable length code (Fig. 3, VLC), wherein a code length of the variable length code is shorter as the difference value is smaller, or equal to a code length of a neighboring difference value of said difference value (Fig. 4).