Abstract: This paper proposes an image forgery detection scheme based on JPEG compression properties, which aims to identify a special type of images that are composed of contents from different JPEG images. Inconsistency in compression qualities and block boundaries in a suspicious image can provide a clue for forgery detection. By recompressing the image with different quality factors and analyzing the induced distortion, we can estimate the quality factor initially used in the main area of the image. Thus, inconsistency can be found from fluctuation of distortion energy in different areas. The proposed scheme is capable of identifying objects from different origins, and provides a useful means of digital forensics.

Key words:

passive image forensics, image composition, JPEG compression