Tamper detection based on the consistency of quantization error caused by multiple JPEG compression

When creating a digital forgery to a JPEG image, it is often involved uncertain times of compression, which may lead to the limitation of some current methods for JPEG tamper detection. This paper intends to do a research towards multiple JPEG compression forensics detection technology, which based on the theory of double JEPG compression detection algorithm proposed by Farid. Multiple JPEG compression detection algorithm based on the consistency of quantization error is proposed in this paper to deal with the situation that tampered images were compressed with quality factors ranging from low to high. The algorithm makes use of the consistency of the DCT coefficients quantization error between the unrecovered image and the recovered image when compressed with special quantization matrix to detect the compression trace. This technique is used to detect tampered image and obtain a good result.