Advanced Digital Image Forgery Detection: a Review

The use of digital photography has increased over the past few years, the trend which opens the door for new and creative ways to forge images. Now a day’s several software’s are available that are used to manipulate image so that the image is look like as original. Images are used as authenticated proof for any crime and if these image does not remain genuine than it will create a problem. Detecting these types of forgeries has become serious problem at present. To determine whether a digital image is original or doctored is a big challenge. To find the marks of tampering in a digital image is a challenging task. A copy-move image forgery is done either for hiding some image entity, or adding more minutiae resulting in forgery. In both the case, image reliability is lost. Although this technology brings many advantages but it can be used as a confusing tool for hiding facts and evidences. In the paper, first, classification of Image forgery detection techniques is discussed and the two important techniques for pixel based forgery detection are discussed. A technique for copy-move forgery detections discussed. But this approach takes into account only shifting of copied regions. So another technique is discussed for fast-copy-move detection. Basic design and algorithm of proposed system is on the basis of above mentioned techniques. First technique i.e. copy move forgery has lower computational complexity but the final result is not precise, on the other hand second approach is complex but precise. Main disadvantage of second technique is that it is not be able to detect very small copied regions. Proposed system will cover disadvantages of both the system and can be robust to various types of copy move processing. All the methods which have been suggested draw strengths from different transforms to make them robust against post processing and to reduce the number of logical blocks to compare. However, as yet no method achieved 100% robustness against post processing operations.