Image processing device and method

In an image processing method for reducing an input image while preventing moire without deterioration of image quality, presence/absence of periodicity is detected for each pixel on the input image, and if there is periodicity, an image period is detected (S 4 ). Sample points are sequentially extracted from the input image at prescribed sampling intervals (S 5 ). A value is obtained by multiplying the image period by n (n is a natural number) that exceeds the sampling interval, to set a smoothing area. Pixels around a sample point is smoothed in the set smoothing area. The pixel value for a reduced image is obtained (S 6 ). If there is an unprocessed sample point (NO at S 8 ), the step goes back to S 6 , and the next sample point is subjected to a similar process. If the process is terminated for all the sample points (YES at S 8 ), the reduced image is output.