JPEG image tampering detection based on blocking artifacts

Abstract

In the modern world, digital images play very important role in areas like insurance processing, intelligence services, surveillance systems and forensic investigation. After the advent of the digital medium, image forgery has become a threat. In today’s digital age, because of the availability of many image editing and processing tools it is possible to change the information represented by a digital image very easily without leaving any obvious traces of tampering. Since tampering of digital images has become so easy, integrity or authenticity of digital images has become a question, resulting in a need for robust and reliable tamper detection methods. One of the methods that allowed copied areas actual detection on doctored JPEG images is blocking artifacts method. This study analyzes the blocking artifacts method and then proposed a new method to improve it. The improvement enables the blocking artifacts method to detect manipulations that uses painting technique. The proposed method called a Marker algorithm was added to the blocking artifacts method proposed by Tralic, et al. (2012). The addition of this algorithm facilitates the detection process of the blocking artifacts method by making the tampered area more visible. Finally, this study evaluated the proposed method in detecting a tampered area by using the percentage of effective detection as a measure. The analysis shows that the proposed method is capable of making the tampered area more visible, thus improving the blocking artifacts method.