19 February 2014 Two improved forensic methods of detecting contrast enhancement in digital images
Author Affiliations +
Abstract
Contrast enhancements, such as histogram equalization or gamma correction, are widely used by malicious attackers to conceal the cut-and-paste trails in doctored images. Therefore, detecting the traces left by contrast enhancements can be an effective way of exposing cut-and-paste image forgery. In this work, two improved forensic methods of detecting contrast enhancement in digital images are put forward. More specifically, the first method uses a quadratic weighting function rather than a simple cut-off frequency to measure the histogram distortion introduced by contrast enhancements, meanwhile the averaged high-frequency energy measure of his- togram is replaced by the ratio taken up by the high-frequency components in the histogram spectrum. While the second improvement is achieved by applying a linear-threshold strategy to get around the sensitivity of threshold selection. Compared with their original counterparts, these two methods both achieve better performance in terms of ROC curves and real-world cut-and-paste image forgeries. The effectiveness and improvement of the two proposed algorithms are experimentally validated on natural color images captured by commercial camera.
© (2014) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Xufeng Lin, Xingjie Wei, Chang-Tsun Li, "Two improved forensic methods of detecting contrast enhancement in digital images", Proc. SPIE 9028, Media Watermarking, Security, and Forensics 2014, 90280X (19 February 2014); doi: 10.1117/12.2038644; https://doi.org/10.1117/12.2038644
PROCEEDINGS
10 PAGES


SHARE
Back to Top