Detection of Copy-Move Forgery of Digital Images Using Discrete Wavelet Transform and Cosine Transform Coefficients Decomposition

In Copy-Move forgery، a part of an image is copied and pasted to another place at the same image. This type of manipulation is performed for add details or to conceal unwanted portions of the image. In this paper، we present an improved method using Discrete Wavelet Transform and Cosine Transform Coefficients Decomposition to detect Copy-Move forgery and its challenges. In the proposed method، with utilizing the nature of Wavelet Transform، Singular Value Decomposition and lexicographically a sorting salient improvement is yielded in comparison with relative algorithms. Although a reduction of detection accuracy occurs، it is negligible because of the increase in speed. Since human eye is more sensitive to lower frequencies، Cosine Transform can successfully detect the forged part even when the copied area is manipulated with additional operation such as retouch. Experimental results show that the proposed scheme accurately detects such specific image manipulations as long as the copied region is not rotated or scaled.