A photographic forensic case study: Myths, principles and techniques
This paper introduces new approaches for photography forensic techniques. The first approach is on a referenced 3D photography forensic study. Two controversial photos taken by Alice and Bob are precisely analyzed based on claims from both sides. Using Google Map and these two given photos, we generate a 3D model to figure out whose claim is closer to the truth. Through thorough 3D simulations, one perceptual error made by Alice is corrected. Wrong presumptions based on false perceptual errors are corrected using referenced 3D simulations. Second, an optical aberration problem is analyzed. This paper points out that not all vanishing points can be available by drawing straight lines since distorted photos due to lens aberration can cause curvilinear perspectives which are different from linear perspectives. Third, the possibility of composite photos is also studied. Re-sampling and its technical solution is provided. As a case study, this paper presents two principles for forensic analysis and provides technical solutions. (C) 2011 Elsevier Ltd. All rights reserved.
photography forensics perceptual errors photographic distortions signal processing