The real fun is how to sign the image (or other binary file) outside the web page without altering the image file (so that non-compliant viewer programs could still display the image).

Some graphics formats allow comments, e.g. gif

I suppose if you wanted to get really fun, you could mess with the least significant bits.

andy.

In reply to Re: (ichimunki) Re x 3: Digital Signatures on Web Pages by andye
in thread Digital Signatures on Web Pages by John M. Dlugosz

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