A Comparative Analysis on Copy Move Forgery Detection in Spatial Domain Method Using Lexicographic and Non Lexicographic Techniques

A digitally altered image, often leaving no visual clues of having been tampered with, can be indistinguishable from an authentic image[1]. Authenticity of digital images plays important role in various fields like medical, legal, criminal, and journalism. Due to rapid advances and availabilities of powerful image processing software, digital images are easy to manipulate and modify for ordinary people. This makes it more and more difficult for a viewer to check the authenticity of a given digital image. In the fields such as forensics, medical imaging, e-commerce, and industrial photography, authenticity and integrity of digital images is essential. This motivates the need for detection tools that are transparent to tampering and can tell whether an image has been tampered just by inspecting the tampered image[3]. Copying parts of an image and pasting in the same image for covering unwanted information or creating a fake image by splicing two or more images are most used techniques in digital image manipulation. These are called copy-move and image-splicing techniques respectively. In this paper we focus on copy-cover image forgery using spatial domain method and do the comparative analysis for lexicographic and non lexicographic techniques.