Abstract: In order to solve these defects such as low forgery detection precision and difficult to detect small tampered area induced by producing color interpolation noise with low resolution for using the color filter array in current image forgery location technologies, the image forgery detection algorithm based on pixel prediction error coupled likelihood mapping was proposed in this paper. Firstly, the green component is extracted from the image based on the color filter array CFA; then the prediction error and its local weighted variance model were constructed by embedding the weight factor; and the model of the false feature statistics was defined by prediction error and Bayes theory to identify the feature value that tend to zero; Finally, the likelihood ratio of the feature was built by the feature statistical model to output forgery mapping for finishing the detection. Simulation results showed that: this algorithm had better robustness to identify small false pixels, and it had higher Area under the ROC curves value and ideal ROC curve.

Key words: Image forgery; Forgery mapping; Prediction error; Forgery feature statistics; Color filter array; Likelihood ratio