Liveness detection using time drift between lip movement and voice

Liveness check through measuring synchrony between the lip and the voice in video sequence has been proved to be a feasible way to prevent spoofing attacks. The generic methods utilize degree of audiovisual correlation to judge consistency. However, little attention is paid to the audiovisual time drift difference between live recordings and fraudulent attacks. In this paper, the time shift difference and the delay range is concluded by delay estimation experiments on VidTIMID. According to the conclusion, we propose an improved "liveness" scores evaluation algorithm for audio-video identification system. Experimental results on the same database show that the proposed algorithm got better performance. In comparison with the traditional methods, the EER (Equal Error Rate) averagely decreases about 5%.