Detection of Copy-Move Image Forgery Using DCT

Abstract

With the advancements in computer technology digital image tampering like copy-move forgery has become frequent. In this paper, we present a novel DCT-based technique for detecting copy-move forgery. DCT is applied to each fixed-size overlapping block of image to represent its features. The dimension of the features is reduced using truncation. Then the feature vectors are lexicographically sorted and, duplicated image blocks will be neighboring in the sorted list. Thus duplicated image blocks will be compared in the matching step. To make the method more robust, a scheme to judge whether two feature vectors are similar is imported. Simulation results show that the proposed technique is capable of detecting the duplicated regions even when an image was distorted by JPEG compression, blurring or additive white Gaussian noise.