Identity requirements in information systems can be satisfied by the integration of biometric technologies with cryptography algorithms. In this field, one of the most important areas is the generation of strong cryptographic keys produced from many kinds of biometrics. This paper describes some solutions within this scope focusing on an efficient approach to generating cryptographic keys from visual patterns containing personal information. Generated cryptographic key may be identified by user features, and used by particular persons. In particular, key generation using palm images and coronary vessels will be presented.