由于图像在经过一次 JPEG 压缩和双重 JPEG 压缩之后其 DCT 系数具有一定的相关性，通过对这种相关性进行分析，提出了一种基于 JPEG 图像双重压缩特性的图像篡改检测算法，并用此算法检测图像是否经过篡改和定位篡改区域。

-Since the image after a first JPEG compression JPEG compression and double its DCT coefficients having some relevance, by this correlation is analyzed, and an image based on JPEG image compression characteristic double tamper detection algorithm, and the algorithm used to detect whether the image been tampered with and locate the tampered areas.