Probability of a unique crypto key generation based on finger's different images with two scanners

In practical cases, one finger is always scanned with different scanners at different time, which generates different fingerprint images. The key issue of the fingerprint-based cryptosystem is how to realize a unique crypto key from a fingerprint feature data which may differ from scanner to scanner. In this paper, the main difference between the fingerprint key-generation cryptosystems and the fingerprint-based recognition system was studied and a crypto key generation scheme based on one fingerprint image was proposed. The experimental results showed that about forty percent fingers can generate a same crypto key even if the images are from different scanners. That is to say, a unique crypto key could be generated based on different fingerprint images of one finger even these images were scanned with different scanners. This means the efforts of future work should be the technology of image quality checking and key generation scheme.