PICTURE DECODING METHOD AND DEVICE THEREFOR

摘要

PROBLEM TO BE SOLVED: To efficiently remove a block distortion contained in a picture signal and to improve the quality of a picture in the ratio of signal to noise. SOLUTION: A code is decoded from encoding data 102 in a code decoding part 103 and a quantization conversion part 104 calculates the quantization representative value and the quantization clipping range of a conversion coefficient. The quantization representative value is converted in an inverse orthogonal conversion part 105 and the decoding picture signal is obtained. The picture signal is restored in a maximum posteriori probability estimation part 106 and the conversion coefficient is obtained in an orthogonal conversion part 108 through a conversion judgment part 107. The conversion coefficient is compared with the quantization clipping range in a coefficient comparison part 109. When it is settled in the quantization clipping range, the conversion coefficient is returned to the inverse orthogonal conversion part 105 as it is. When it is not settled in the quantization range, the coefficient settled in the quantization range is obtained in a random number generator 110 and it is returned to the inverse orthogonal conversion part 105.