Finger vein image retrieval via affinity-preserving K-means hashing

Efficient identification of finger veins is still a challenging problem due to the increasing size of the finger vein database. Most leading finger vein image identification methods have high-dimensional real-valued features, which result in extremely high computation complexity. Hashing algorithms are extraordinary effective ways to facilitate finger vein image retrieval. Therefore, in this paper, we proposed a finger vein image retrieval scheme based on Affinity-Preserving K-means Hashing (APKMH) algorithm and bag of subspaces based image feature. At first, we represent finger vein image by Nonlinearly Sub-space Coding (NSC) method which can obtain the discriminative finger vein image features. Then the features space is partitioned into multiple subsegments. In each subsegment, we employ the APKMH algorithm, which can simultaneously construct the visual codebook by directly k-means clustering and encode the feature vector as the binary index of the codeword. Experimental results on a large fused finger vein dataset demonstrate that our hashing method outperforms the state-of-the-art finger vein retrieval methods.