PICTURE CODING AND DECODING METHOD AND ITS DEVICE

摘要

PROBLEM TO BE SOLVED: To reduce a bit quantity necessary for coding while suppressing the deterioration in a picture quality in the coding of the picture. SOLUTION: A shape extraction means 2 binarizes a picture signal 1 by a prescribed threshold value to extract shape information. Next a shape coding means 4 codes this shape information by a binary picture coding technique to output as a shape coded signal. On the other hand, an off-shaped pixel substituting means 6 inputs shape information 3 and the picture signal 1 to judge the in-shape or off-shape by shape information 3 and to substitute off-shaped pixel of the picture signal 1 with such a prescribed rule as reduces high frequency components. As the result, the coding efficiency of a picture signal coding means 7 at an object area boundary part is improved.