摘要 |
PURPOSE:To evaluate blur itself regardless of the level of a picture signal by extracting an edge part of an input image, obtaining the average picture element value of the edge part, and using the average picture element value as an index for the picture quality of input picture elements. CONSTITUTION:An image D of a peripheral part (edge part) obtained when an image B is magnified into an image C is taken out by an exclusive OR of the images B and C or by subtracting the image B from the image C. Then a sum IB of the picture element values of an input image A included in the area of the binarized image B is obtained. The value of IB is divided by an area SB of the image B (pattern part) to obtain the average density MB (average picture element value) of the pattern part. Then a sum ID of the picture element values of the image A included in the area of the image D of an edge part is obtained, and the value ID is divided by an area SD of the image D to obtain the average density MD of a peripheral part. Then an average density ratio R is obtained between a pattern part B and an edge part D. The picture quality is decided by the value of the ratio R. Thus the picture quality is quantitatively evaluated regardless of the level variance of an input picture signal. |