An improved tamper-detection method for digital images

With the wide use of digital multimedia, there is increasing interest in copyright protection as well as tamper detection. However, most of the research in digital watermarking is more concerned with the problem of copyright protection; we believe that the prevention of tampering has the same degree of importance. In this paper, we propose a method that can detect tampering and locate the attacked area in a digital image. The method uses the quantizing DCT coefficients of images selectively in such a way that a tamper destroys the conditions embedded in the DCT coefficients.