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Subject: Re: randomness and playlists
From: Andrew Jamieson (
Date: 2002-05-02

This is a good idea. A couple of questions:

* What are you planning to use as the entropy source for the random seed?
The least significant digits on keystroke timing and hard disk spin-up
timing is sometimes used in crypto circles. Also there are the A/D inputs
(that go somewhere, and may not be usable, I'll check this).

* What algorithm are you thinking of for the iterations (something like
SHA-1 would be indistingushible from random for our purposes, but is
probably overkill)? And how do we stop songs repeating?

Just trying to make myself feel useful (or at least annoying) ;)


----- Original Message -----
From: "Daniel Stenberg" <>
To: <>
Sent: Thursday, May 02, 2002 1:12 AM
Subject: randomness and playlists

> Hey
> It struck me that if we end up with a playlist consisting of lots of
> and we want random selection, press play and a random tune starts... you
> N pieces of music and then shuts off.
> Now, you start the player again. Where do you start again?
> My thoughts:
> We do no true random selections. We do a random based on a seed. The
> becomes the same every time given the same seed.
> This way, we can store "index" and "seed" only, and then we always know
> track we played before this one (in fact, we have full backtrace all the
> way), which one is next etc. No matter if you shut off the player in
> between... And you won't hear the same tune twice until all tunes are
> If you're not happy with the random order, you get a new scramble by
> the seed.
> --
> Daniel Stenberg -- Hacking Archos =>

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