18 May
2010
18 May
'10
11:04 a.m.
On Tue, May 18, 2010 at 13:34, Liam Proven <lproven at gmail.com> wrote:
True, and I did consider that - after all, it
apparently worked fine.
But somehow seems subtly /wrong/ to me. It /ought/ to be uncompressed.
In this case, the _optimal_ compression scheme would be to convert raw
audio into binary data of the actual bits encoded, then recreate the
audio from the bits. Effectively, emulate the tape I/O circuitry of
the Apple II.
After all, mp3 and friends are compression schemes optimized for the
human hearing system, making sure the decoded audio sounds the same as
the original audio, while the waveform will not match the original.
Given that analog recording devices were designed with the same goal,
it's no surprise it works. It's just not efficient :-)
If you want to store the data uncompressed, it'd be worth thinking
about the sampling rate a bit: my guess is that standard phone rate
of 8000 Hz would be sufficient. But it depends on the modulation
scheme the Apple uses.
--
Joachim Thiemann :: http://www.tsp.ece.mcgill.ca/~jthiem