IMAGE DECODER

摘要

PROBLEM TO BE SOLVED: To prevent deterioration in the image quality in the case of decoding a coded signal and to prevent the image quality from being considerably deteriorated even on the occurrence of missing information. SOLUTION: An inverse quantization means 22 applies inverse quantization to a coded prediction error signal to obtain an orthogonal transform coefficient and an error inverse quantization means 23 applies inverse quantization to a quantized signal denoting a quantization error to obtain a quantization error of the orthogonal transform coefficient. An error adder means 24 adds outputs of the inverse quantization means 22 and the error inverse quantization means 23 and an inverse orthogonal transform means 25 applies inverse orthogonal transform to the result of sum. Then an adder means 26 adds an image signal stored in a frame memory and an output signal of the inverse orthogonal transform means 25 and provides an output of an image signal as a decoding result.