Patent ID: 7715636

Claim:
A decoding apparatus comprising: a random-number generating section that generates random numbers according to distribution of original data corresponding to respective quantization indexes of entropy-encoded code data; a dequantization section that sets respective quantization indexes of the entropy-encoded data to a quantization index of interest in order, wherein if a dequantization value can be estimated for the quantization index of interest based on a threshold comparison with neighboring quantization indexes, the dequantization section generates a dequantization value for the quantization index of interest using a dequantization-value estimating section without using the random numbers, and if the dequantization value cannot be estimated for the quantization index of interest, the dequantization section generates the dequantization value for the quantization index of interest using the random numbers generated by the random-number generating section, and the dequantization section includes a dequantization-value outputting section that generates and outputs the dequantization value to be used as decoded data based on the dequantization value generated by the dequantization section.