There are various simple compression schemes available. Most use some
variation of the VSDC method (Variable Slope Delta Compression) wherein
you store nybbles which contain the deltas between samples (DC), or the
slope required to get to the next sample (VSDC).

You can also look at thowing away near silence by using an escape
code and RLL (run lengh limiting) compression as used in Fax machines
and the like.

Also look at the various formats for compression in WAV files to see if
one of them meets your needs. (somewhere on
http://support.microsoft.com)

Robert


Tim Crist wrote:
>
> Help.
>
> I'm trying to reproduce low fi of 300 to 8Khz while using a minimal amount
> of flash memory to do so.  I also want to keep the code simple, and within
> the confines of an 8 bit processor if possible.
>
> I've looked at MP3 and other compression techniques, but most of them
> require a large amount of processing.
>
> First a sanity check:  If I want 3 minutes of 8 bit sound reproduced with
> the max freq. of 8Khz I'll get:
>
> (180 seconds) * (8 bits) * (16000 pulses/ second) = 23.04 megbits of memory
> required
>
> right?
>
> Is there an easy method to half, quarter, or more this audio info to save on
> memory space?
>
> Thanks,
>
> Tim Crist
>
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