LBP-DCT based copy move forgery detection algorithm

Abstract

Increase on the availability of the image editing software makes the forgery of the digital image easy. Researchers proposed methods to cope with image authentication in recent years. We proposed a passive image authentication technique to determine the copy move forgery. First, the method divides the image into overlapping blocks. It uses LBP (Local Binary Pattern) to label each block. Labeled blocks are transformed into frequency domain using DCT (Discrete Cosine Transform). Sign values of the first fifteen coefficients of the zigzag scanned block plus average Y, Cb, Cr values constitutes the feature vector for the block. Finally, the feature vectors are lexicographically sorted and element-by-element similarity measurement is used to determine the forged blocks. Experimental results show that the method has higher accuracy ratios and lower false negative values under some post processing operation compared to other DCT based methods. Our method can also detect multiple copy move forgery.