Fast and robust identification methods for JPEG images with various compression ratios

We propose two identification methods for JPEG-coded images. The purposes are to identify the images that are compressed from the same original image with various compression ratios in fast and robust manner. The first approach can avoid identification leakage or false negative (FN), and could result in a few false positives (FP). The second approach can avoid both FN and FP, with a slightly longer processing time. By combining the two schemes, a faster and a more perfect identification can be achieved, in which IN and FP can be avoided.