JPEG2000 Image Tamper Detection Based On Regularity Of Wavelet Coefficients

Nowadays, with the rapid development of computer network and communication technology, various forms of digital media have been widely used. However, due to the widespread use of powerful image-processing software, it is increasingly easier to tamper digital images. The traditional method to distinguish trueness or fake is to embed digital watermarks or signatures in digital images in advance. But it still has a lot of weaknesses. Therefore it forms a new and important research direction to authenticate digital images without watermarks or signatures, which is called passive image detection.In the course of image forgery with paste-copy, forgers often produce some singularity points at the edge of image junction. A specific contact between the logarithm of local maximum value of wavelet transform coefficient and the singularity points of image can be used to achieve the tamper detection of images.This dissertation presents a new JPEG2000 image tamper detection measure based on regularity of wavelet coefficients. Its algorithm principle is: Firstly, this method extracts the image edge information. Then it accesses to the corresponding pixels of information on the image sub-bands with UDWT (Undecimated Discrete Wavelet Transform). Finally, curve fitting is used. The experimental results show that the algorithm can detect JPEG 2000 tampered image ideally. In addition, this method can be used effectively.