A method for protecting digital images from being copied illegally

Due to the recent growth of digital multimedia transmissions on the Internet, the need for the intellectual property rights protection of multimedia information, like images, music and videos, has become more and more important. Many digital watermarking techniques have been proposed to solve this problem by hiding an invisible watermark in an image to prove the ownership of the image. In this paper, however, we propose a new scheme for the copyright protection of images. Our scheme is a DCT-based method and does not actually hide the watermark in the image. In addition, this scheme is extremely applicable for multiple watermarking. According to our substantial experimental results, this scheme is strongly robust against various kinds of image processing attacks.