IMAGE PROCESSING METHOD, IMAGE PROCESSING UNIT, IMAGE CODER, AND IMAGE DECODER

摘要

PROBLEM TO BE SOLVED: To provide an image coder and an image decoder that can suppress leakage of original image data through hard copy. SOLUTION: The image decoder 250 is provided with an image decoding means 209 that decodes a coded input image entered from a data input terminal IN, an electronic watermark detection means 214 that detects an electronic watermark from the decoded image, a noise superimposing means 214 that superimposes a noise on the decoded image, and an output image buffer 210 that temporarily stores an output image on which the noise is superimposed. The output image is outputted from an image output terminal OUT 1. Since the image outputted from the output terminal is always altered through the superimposition of the noise, the original cannot be stolen by means of hard copy or the like.