15 - Passive-blind Image Forensics

Abstract

This chapter discusses passive-blind image forensics (PBIF). PBIF is concerned with two problems: image forgery detection and image source identification. Most of the image forgery detection techniques are associated to the specific image forgery creation techniques. Forgery detectors uncover act of fabrication by assessing the authenticity of a given image. There are two approaches for image forgery detection: detecting the authentic characteristics of images and detecting the telltale characteristics specific to the image forgery creation techniques. The goal of the passive-blind image source identification is to identify the type of image source. Identification of the image source helps in deciding whether an image is acceptable for a specific application. One problem of concern in image source identification is the classification of photographic images (PIMs) and photorealistic computer graphics (PRCGs), so the chapter summarizes the differences between PIMs and PRCGs––namely, object model difference, light transport difference, and acquisition difference. The chapter gives a reference of data set by enlisting the category of images in it and concludes with a review of the automatic or the semi-automatic computer techniques for image forgery creation.