Reduced Time Complexity for Detection of Copy-Move Forgery Using Discrete Wavelet Transform

As result of powerful image processing tools, digital image forgeries have already become a serious social problem. In this paper we describe an effective method to detect Copy-Move forgery in digital images. Our technique works by first applying DWT (Discrete Wavelet Transform) to the input image to yield a reduced dimensional representation [1]. Then the compressed image is divided into overlapping blocks. These blocks are then sorted and duplicated blocks are identified using Phase Correlation as similarity criterion. Due to DWT usage, detection is first carried out on lowest level image representation. This approach drastically reduces the time needed for the detection process and increases accuracy of detection process.