Image processing method and image processing device

摘要

An image processing method and device computes the image quality as an evaluation value, determine the image quality based on this evaluation value, and employ a restoration process in accordance with image quality when this image quality is poor. The image processing device includes an image quality computation unit to extract a characteristic amount to determine the image quality of the image data entered by an image input device and to compute the characteristic amount as the evaluation value, a binary threshold determination unit to determine a binary threshold value for the image to be processed using an evaluation value obtained by the image quality computation unit, and an image quality improvement unit to determine candidates for image quality improvement unit by extracting sections which have the possibility of image quality deterioration based on the characteristics and to perform image quality improvement on candidates for image quality improvement processing using the evaluation value obtained by said image quality computation unit. The image quality computation unit extracts a characteristic amount of the image in sections with the possibility of image quality deterioration unit determines the image quality using this characteristic amount as an evaluation value; the binary threshold value determination means determines the optimum binary threshold value on the basis of this evaluation value; and the image quality improvement unit extracts candidates for and performs the image quality improvement process only when image quality improvement is necessary.