DEVICE AND METHOD FOR PROCESSING IMAGE AND COMPUTER READABLE STORAGE MEDIUM

摘要

PROBLEM TO BE SOLVED: To provide an image processor for performing dynamic range compression while holding the high frequency components of source images. SOLUTION: A differential coefficient calculation circuit 112a calculates a coefficient based on the differential coefficient of a gradation conversion curve used for gradation conversion in a gradation conversion circuit 112e. A smoothed image preparation circuit 112b prepares the smoothed image (low frequency image) of the source image and a high frequency component preparation circuit 112c calculates the difference between the prepared smoothed image and the source image as the high frequency component. A high frequency component addition circuit 112d adds the calculated high frequency component to the source image or the smoothed image based on the calculated coefficient and the gradation conversion circuit 112a gradation-converts the image to which the high frequency component is added.