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Subject: Re: playlist ideas
From: Matt.OReilly_at_wachovia.com
Date: 2002-04-23


>> You could have one global/master playlist which loads other playlists
>> for each directory/block/whatever. This would cut down considerably
>> on the memory requirements for loading playlists, we'd only have one
>> HDD spinup when changing playlists, and it would make adding new songs
>> to the playlist much easier.

>The downside is that you can't randomise beyond the currently playing
>list. For me, an important goal for this project is whole-disk random
>playback.

There are a couple of ways around this, IMO. One would be to maintain
control (through the firmware) of the master playlist, so that when a
playlist finished playing, it would return control to the master playlist.
(Which would have to happen anyway.) This functionality could be extended
so that the Archos would return control to the master after playing a
specific track in the sub-playlist.

More problematic it seems would be keeping track of which songs had already
played, so as not to play the same song two or three times sequentially
from random selection. (This would make it not truly random after the
first song, but there's nothing truly random out there anyway, right?)
Perhaps one way around this would be to have the random generator assign a
unique value which it uses to map to a particular song. For instance:

Master
     -list1
          -song1
          -song2
          -song3
          -song4
          -song5
     -list2
          -song6
          -song7
     -list3
          -song8
          -song9

If the random number generator chose 25B for instance, it would cycle
through the playlists 25B times (25B mod n, where n is the number of
entries in the master list), then cycle through the songs in the list 25B
times (25B mod p) and play the song at that entry. The Archos would then
cache 25B and make sure that that song was not repeated. (Pick a number,
check the list, if match then re-pick...)

Someone might want to check my math theory here - there may be prime
numbers or multiples of n/p which would never be played. (Perhaps [x+1 mod
n] or [x*2 mod n] would work better...) But I think the idea is sound.

Hmmm... a lot of space for a little idea... Oh well.

Matt



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