1. A method of authenticating a digital still image captured using a digital image capture device and processed using signature data to produce an authentication signature wherein the authentication signature is stored at a remote location for later use in verifying the authentication of the captured digital still image, the method comprising the steps of: transmitting the digital still image to the remote location; accessing the signature data; applying the signature data to the transmitted digital still image to produce a verification signature; accessing the authentication signature stored at the remote location; and comparing the authentication signature with the verification signature to determine the authentication of the transmitted digital still image.