Tampering detection for composite images based on re-sampling and JPEG compression

Image forgery detection is an important issue in digital forensics. We propose in this manuscript an algorithm for image composite tampering detection. In the algorithm, we first divide a possibly composite image into overlapped blocks, then define and extract a block measure factor which contains both re-sampling characteristics and JPEG compression characteristics for each block, and apply the block measure factor to discriminate the tampered regions from non-tampered regions. Experimental results show that with the proposed algorithm, composite images are correctly recognized, and at the same time, the tampered regions are determined effectively.