Learning to hash faces using large feature vectors

Face recognition has been largely studied in past years. However, most of the related work focus on increasing accuracy and/or speed to test a single pair probe-subject. In this work, we present a novel method inspired by the success of locality sensing hashing (LSH) applied to large general purpose datasets and by the robustness provided by partial least squares (PLS) analysis when applied to large sets of feature vectors for face recognition. The result is a robust hashing method compatible with feature combination for fast computation of a short list of candidates in a large gallery of subjects. We provide theoretical support and practical principles for the proposed method that may be reused in further development of hash functions applied to face galleries. The proposed method is evaluated on the FERET and FRGCv1 datasets and compared to other methods in the literature. Experimental results show that the proposed approach is able to speedup 16 times compared to scanning all subjects in the face gallery.