Identification of Motion-Compensated Frame Rate Up-Conversion Based on Residual Signals

Motion-compensated frame rate up-conversion (MC-FRUC) is originally presented to increase the motion continuity of low frame rate videos by periodically inserting new frames, which improves the viewing experience. However, MC-FRUC can also be exploited to fake high frame rate videos or splice two videos with different frame rates for malicious purposes. A blind forensics approach is proposed for the identification of various MC-FRUC techniques. A theoretical model is first built for residual signal, which is exploited as tampering trace for blind forensics. The identification of various MC-FRUC techniques is then converted into a problem of discriminating the differences of residual signals among them. A pre-classifier is designed to suppress the side effects of original frames and static interpolated frames in candidate videos. Then, spatial and temporal Markov statistics features are extracted from the residual signals inside the interpolated frames for MC-FRUC identification. Five open MC-FRUC softwares and six representative MC-FRUC techniques have been tested, and experimental results show that the proposed approach can effectively locate interpolated frames and further identify the adopted MC-FRUC technique for both uncompressed videos and compressed videos with high perceptual qualities.