BACKWARDS COMPATIBLE, MULTI-LEVEL REGIONS-OF-INTEREST (ROI) IMAGE ENCRYPTION ARCHITECTURE WITH BIOMETRIC AUTHENTICATION Topics: Authentication and Watermarking; Design and Implementation of Signal Processing Systems; Multimedia Databases, Indexing, Recognition and Retrieval In Proceedings of the Second International Conference on Signal Processing and Multimedia Applications - Volume 0ICETE, 320-325, 2007 , Barcelona, Spain