Boosting Face Recognition in Real-World Surveillance Videos
Face recognition becomes a challenging problem in real-world surveillance videos where the low-resolution probe frames exhibit variations in pose, lighting condition, and facial expressions. This is in contrast with the gallery images which are generally frontal view faces acquired under controlled environments. A direct matching of probe images with gallery data often leads to poor recognition accuracy due to the significant discrepancy between the two kinds of data. In addition, the artifacts such as low resolution, blurriness and noise further enlarge this discrepancy. In this paper, we propose a video based face recognition framework using a novel image representation called warped average face (WAF). The WAFs are generated in two stages: in-sequence warping and frontal view warping. The WAFs can be easily used with various feature descriptors or classifiers. As compared to the original probe data, the image quality of the WAFs is significantly better and the appearance difference between the WAFs and the gallery data is suppressed. Given a probe sequence, only a few WAFs need to be generated for the recognition purpose. We test the proposed method on the ChokePoint dataset and our in-house dataset of surveillance quality. Experiments show that with the new image representation, the recognition accuracy can be boosted significantly.