Re: Recode to Play MP3?

["Michael J. Mahon" <mjmahon@aol.com>]

Steve ][ wrote:
> There was an app for 68k Macs that would play mp3s, it would first
> recode them to AIFF and buffer them and play them (or replay from
> bufer). 
>
> Just wondering, from a technical standpoint by Those Who Know (TM),
> what it would take to do anything similar on the IIGS. I was thinking
> that recoding would be done on a Mac or PC and then copied over to the
> IIGS, but I don't know if/what the platform could handle.

Practically, the speed of Apple II machines requires that the sound
be pre-decoded to a "raw" 8-bit PCM sound file (like a simple .wav
format, minus the header).

Once the file is in raw sample format, it can be played on *any*
Apple II, subject to memory limitations.  For 8-bit Apple II's,
my DAC522 plays the upper 5 bits of each 8-bit sample at a sample
rate of 11.025kHz.  It is available in the SOUND.EDITOR package
on my website.

As used in SOUND.EDITOR, it loads a sound segment into RAM, and so
is limited to a little less than 2 seconds of sound.  Other ways of
"packaging" DAC522, like IISOUND, permit the sound(s) to be loaded
into a RAMworks-type memory expansion card, permitting longer sounds
(but no editing) at the price of occasional "pops" as the player
transitions from bank to bank.

I've been thinking about making a player program that runs from
sounds stored in a Slinky/RAMfactor-style card, that would permit
over 90 seconds of audio at 5-bit fidelity, or over three minutes
at 4-bit fidelity.  (Maybe I could get the 5th bit back by doing a
slight decompression on the fly, but that's another story.  ;-)

The IIgs (only) can play 8-bit sampled sounds while reading more of
the file from (fast) disk, allowing a virtually unlimited length.
I'm sure someone here remembers the name of that sound player...

-michael

NadaNet file server for Apple II computers!
Home page:  http://members.aol.com/MJMahon/

"The wastebasket is our most important design
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