Divide the composite image into overlapped blocks and calculate the measure of each block. The forged area can be effectively exposed by checking inconsistencies of blockingartifact.
然后将待检测图像重叠分块并计算其相应块效应测度，利用块效应不一致性检测篡改区域。
2
However, in the compression process of blocking image data, severe boundary artifact will be produced because of boundary extension and coefficient quantification.