>> For example, let's say I have a large number of .WAV files in the
>> harddrive I'm looking at, is there any easy way for me to extract the
>> major frequencies from them, assuming I also specify an estimated
>> sample rate, a particular playback rate, and the depths into the file
>> I am examining? (This would be the first step toward creating
>> sound envelopes for them. I think.)
>>
>> Or has somebody already done that, and it's already available as a 'C'
>> program?
Tom Harrington <tph@[EMAIL PROTECTED]
> wrote:
>Err, sure it's possible.
It's not that hard for the Atari ST, just time consuming, and I have
other things to do with my life. But now that I have a Mac 'mini,'
there has GOT to be SOME way of ****ting it over to the Mac. And it is
bound to work a whole lot faster. Maybe there is a 68k emulator out
there somewhere, and the i/o is mapped into the addressing space in a
rational, well-do***ented way?
>I would expect this task to be a decidedly non-trivial one, but that
>doesn't mean it's impossible or that it hasn't been done. If you're
>just starting to learn to write software, you'll need to learn to
>crawl and walk before you can run with a complex project.
Hey, I'm a 68000 assembly language programmer, not a 'C' programmer;
there are fewer instructions and addressing modes for the 68k.
To elucidate the matter a little more, let's suppose I have 100 megs of
null bytes in a .RAW or .WAV file. (I am assuming that .RAW and .WAV
files similarly contain series of 32 bit long words.) If that's the
case, it really doesn't matter what the sample rate is, or what the
playback rate is, you are still going to get a series of zero
frequencies, whether the file was examined in a forward direction, or a
backward direction. Of course, that's a trivial situation. On the
other hand, if your 100 meg file is full of a whole bunch of $ffffffff
long words, you are (I would expect) going to be returning a series
of the highest frequencies that are possible. You might even want to
flag an overflow situation. But if you are dealing with some raw data
sampled from a musical performance - say, a cello and an oboe, the
bytes are going to be anything but well-ordered; the frequencies
returned will depend a lot on what you might specify for a sample rate,
and a playback rate.
I was just hoping someone had already concocted a command along those
lines for the Darwin 'terminal' for the Mac...
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