Even though digital devices, especially digital cameras and camcoders, are getting popular, they are not counted in legal disputes as trustworthy devices. In this paper an image forensics technology is proposed to make digital image capturing devices have legal proof capabilities. For the images taken by digital devices to have legal proof capability, integrity should be guaranteed. Electronic signature was proposed as a means of guaranteeing the integrity of the digital files of images. However, electronic signatures require additional data of digital digest, and cannot survive digital manipulations such as lossy compression, or RST (rotation, scaling, and transformation). This paper suggests a novel algorithm of image forensics that guarantees integrity in nor-mal processing by hiding forensics information into images and identifies locations of forgery and alteration. Images produced by the proposed method maintains high image quality as PSNR over 50[dB] and guarantees integrity up to the quality factor of 85% against JPEG compression.
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