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From: sbarnhar%MAILBOX.MAIL.UMN.EDU@uga.cc.uga.edu ( Shawn Barnhart)
Newsgroups: comp.lang.pascal
Subject: Sound compression
Message-ID: <25947@adm.brl.mil>
Date: 12 Feb 91 20:07:33 GMT
Sender: news@adm.brl.mil
Lines: 14

I don't know much about digitized sound or compression algorithms, but my
guess is that sound compression involves sampling the sampled sound.
IE, say you sample a sound at 22 Khz and you want to compress it.  Wouldn't
you just sample the sample?  Of course this means that you can't go back
to the original sample rate.  Maybe you could save the information that
you don't sample from the sample and try to compress that using the standard
compression utilities/algorithms (Lempl-Ziv, Huffman, et al).  I've never
tried, so your mileage may vary.

There are (supposedly) "advanced" compression utilities for the Mac that can
obtain 20-30% compression of digitized sound (as opposed to resampling).
I don't know what algorithms they may use, though. I imagine they are
proprietary versions of some of the more standard algorithms.
-Shawn