[5794] in cryptography@c2.net mail archive
Re: grabbed video as a source of entropy
daemon@ATHENA.MIT.EDU (Eugene Leitl)
Wed Sep 29 20:33:09 1999
From: Eugene Leitl <eugene.leitl@lrz.uni-muenchen.de>
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Message-ID: <14321.8989.91496.246371@lrz.de>
Date: Tue, 28 Sep 1999 13:20:45 -0700 (PDT)
To: David Honig <honig@sprynet.com>
Cc: Eugene Leitl <Eugene.Leitl@lrz.uni-muenchen.de>, <cryptography@c2.net>
In-Reply-To: <3.0.5.32.19990927182344.0082d730@pop.sprynet.com>
David Honig writes:
> Even if I had the same hardware, perhaps the tolerances on my ADCs are
> different from yours.
>
> And illumination levels will affect certain kinds of noise.
Sure, but the entropy generation rate will be in any case higher than
stuff coming from /dev/dsp
> The point: Measure it.
>
> Use Shannon's entropy formula, for instance.
I'm not very well versed in such matters, and pressed for time in my
day/night job.
> >I wouldn't mind any pointers to sources extracting, say, LSB from
> >grabbed frames.
>
> Distill (irreversibly compress, e.g., by xor'ing several words together)
> your data. Measure again; distill again until 1 bit/baud. Hash before use.
I was looking for sources performing such steps. And I wouldn't want
to crypto-hash lest the raw entropy gets debased by hidden algorithmic
order.
> Any OTP tool should facilitate or automate these steps.
