Biometric Encryption Algorithm Based On Palmprint And Two-Layer Error Correction Technique

Along with social progress and development of information technology, people are increasingly demanding information security. The traditional password and smart cards have been unable to meet the people's safety certification requirements. In this case, biometric technology, with its ease to use and high reliability, has been the focus of extensive research. However, the traditional biometric systems need to store biometric templates. As they are the private data only owned by users, and once lost we cannot make up. If criminal attacker make the biometric templates restoring original data, users will never be able to use the biometrics.Biometric encryption is proposed to protect the biometric templates, which combines the unique characteristics of one person, such as fingerprint, palmprint and iris etc., with the encryption system, encrypts the template and protects the keys. The main difficulty in biometric encryption system is that biometric data are ambiguous, but the keys are accurate, so how to combine the vague biometric data with the accurate biometric key is an important question.Fuzzy commitment scheme provided the best way to solve the problem, which is the combination of error-correcting code and the biometric key, including commitment and decommitment. However, the specific algorithm based on fuzzy commitment scheme is not very rich. Compared with other biometrics, palmprint is easy to collect, containing large amount of information etc., but there is also no realization based on palmprint using the fuzzy commitment. Hence, this paper proposed the biometric encryption algorithm based on the palmprint and the two-layer error correction technique.The two-layer error correction technique uses RS and Hadamard codes to cascade, encodes the randomly generated key, XOR the biometric data after encoding, and storages the results on a smart card. In the decryption stage, we use the fuzzy palmprint data to regenerate the key.In order to improve the contradictions between vagueness and precision, when using the palmprint to realize the two-layer error correction scheme, we should use the subspace-based feature extraction to extract the palmprint data. In addition, to get a longer key, after feature extraction, we reconstructed the palmprint image, and binarized it to get the biometric data.Experiment showed good result, in the decryption phase, the original key could be well recovered, and the False Rejection Rate(FRR) was small. In addition, we analyzed the security of the algorithm.