Detecting doctored images using camera response normality and consistency

The advance in editing techniques has facil-itated people in synthesizing realistic imageshideos that may hard to be distinguished from real ones by visual ex-amination. This poses a problem: how to differentiate real imageshideosfrom doctored ones? This is a serious prob-lem because some legal issues may occur is no reli-able way for doctored detection when human inspection fails. Digital watermarking cannot solve this problem completely. Wepropose an approach that computes the response functions of the camera by selecting appropri-ate patches in different ways. An image may be doctored if the are abnormal or inconsistent to each The normality of the response functions is by a trained support vector machine (SVM). Experiments show that our method is effective for high-contrast images with many textureless edges.