One of the main multimedia forensics topic is image tampering detection, that is assessing the authenticity of a digital image. Information integrity is fundamental in a trial, but it is clear that the advent of digital pictures and relative ease of digital image processing today makes this authenticity uncertain. In particular, we devised a method that is able to localize which parts of an image have been altered. In fact, localization is basic within the process of image examination because it permits to link the modified zone with the corresponding image area and, above all, with the meaning of it.
Forensic instruments dealing with copy-move manipulation quite always provides a localization map, but, on the contrary, only a few tools, devised to detect a splicing operation, are able to give information about localization too. In We have proposed a method to distinguish and then localize a single and a double JPEG compression in portions of an image through the use of the DCT coefficients first digit features and employing a Support Vector Machine (SVM) classifier.
