>An uncrackable system would have to have random keys, with random
>timing as well. A brute force attack could easily determin a fixed
>key since the data of a static image is unchanging.

A real live video signal from a camera starts out as an
analog phenomenon.  There will be noise in the signal, so
each frame won't be identical.  (And even if it were,
one could add a little noise of their own)

Barry

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