Fragile and semi-fragile colour image authentication using weighted finite automata

This paper presents an efficient technique for combined fragile and semi-fragile colour image authentication. The authentication signature is extracted from image representation in the automata domain. In the automata domain the self-similarity of the coloured image is represented using weighted finite automata. The proposed technique is capable of detecting malicious attacks as well as colour tampering whilst maintaining rather simple implementation along with a compact signature length. Experimental results are presented to demonstrate the effectiveness of the proposed technique for well-known images.