  Based on fixed point theory, this paper proposes a simple but efficient
method for image integrity authentication, which is different from Digital
Signature and Fragile Watermarking. By this method, any given image can be
transformed into a fixed point of a well-chosen function, which can be
constructed with periodic functions. The authentication can be realized due to
the fragility of the fixed points. The experiments show that 'Fixed Point
Image' performs well in security, transparence, fragility and tampering
localization.
