Learning Expressive and Generalizable Motion Features for Face Forgery Detection

Previous face forgery detection methods mainly focus on appearance features, which may be easily attacked by sophisticated manipulation. Considering the majority of current face manipulation methods generate fake faces based on a single frame, which do not take frame consistency and coordination into consideration, artifacts on frame sequences are more effective for face forgery detection. However, current sequence-based face forgery detection methods use general video classification networks directly, which discard the special and discriminative motion information for face manipulation detection. To this end, we propose an effective sequence-based forgery detection framework based on an existing video classification method.To make the motion features more expressive for manipulation detection, we propose an alternative motion consistency block instead of the original motion features module.To make the learned features more generalizable, we propose an auxiliary anomaly detection block.With these two specially designed improvements, we make a general video classification network achieve promising results on three popular face forgery datasets.