Research On Detecting The Copy-Move Forgery In The Image

Digital images are easy to manipulate and edit due to availability of powerful image processing and editing software. These forgeries, if used in the multimedia or courts of law, can have an important impact to our society.Now, in the image authentication, there are some passive-blind authentication algorithm emerging which need not to add additive information besides active authentication which based on digital signature and digital watermarking. In this paper, we concentrate on detection of a specific category of digital image forgery—copy-move forgery. Copy-move forgery is a local image forgery technique, in which a part of a digital image is copied and then pasted to another portion of the same image in order to conceal an important object in the scene. This is one of the simple and effective image forgery techniques. Now almost all the detecting approaches are based on block matching, they are less robust or greater complexity in computing. This paper describes a new and efficient algorithm for detecting and localizing this type of malicious tampering. The algorithm is based on the pixel matching. Our technique works by first applying wavelet transform to the input image to yield a reduced dimension representation. The image at the lowest resolution is divided into four subimages, the phase correlation is computed between the four subimages and the shift between the copied region and the pasted region is obtained using it. After shifting the input image, we will mark the copy-move forgery region. The algorithm is easy understood and carried out. The experimental results show that our method is more effective than other exiting algorithms and can successfully detect the type of tampering for digital images that have been subjected to various forms of post copy-move region image processing, including lossy JPEG compression, lossy JPEG2000 compression and filtering after compression.