Program for discrete sampling of audio files?

[Thomas Keller]

Hello there!

I'm currently working on a project for my studies involving multimedia
databases, concentrating on the MM extensions Oracle provides.

The project idea: Wouldn't it be nice to search for any kind of music just
by your mood? - e.g. for depressive guys: fast music (hardcore), if your
girlfriend comes around: slow, silent classic, whatever you might think of.

How to accomplish that? Well, extract/sample the amplitudes in different
frequency areas (e.g. 1kHz, 5kHz, 10kHz, ..., 20kHz) at discrete times like
every half second and store these tupels in the database. Then use standard
SQL AVG and STD (standard deviation) and compare the gathered results
against user-defined thresholds.

Now, I'm looking for a software which is able to extract these sample
information and outputs them in some parsable format, a CLI Linux/Unix OS
program would be great. Does anybody know a program is capable to
accomplish that?

Thanks in advance,
Thomas.

[Steven Winikoff]

Post by Thomas Keller
Now, I'm looking for a software which is able to extract these sample
information and outputs them in some parsable format, a CLI Linux/Unix OS
program would be great. Does anybody know a program is capable to
accomplish that?

You might want to look at Audacity [ http://audacity.sourceforge.net/ ]
or Glame [ http://glame.sourceforge.net/ ].

I don't think either of them can do what you want directly, but both of
them are able to read and edit sound files in various formats. If you
read the source code, you'll probably find what you're looking for.

- Steven
________________________________________________________________________
Steven Winikoff |
Concordia University | "[...] And it didn't stop being magic
Montreal, QC, Canada | just because you found out how it was
***@alcor.concordia.ca | done."
http://alcor.concordia.ca/~smw | - Terry Pratchett

[Mårten Svantesson]

Post by Thomas Keller
Hello there!
I'm currently working on a project for my studies involving multimedia
databases, concentrating on the MM extensions Oracle provides.
The project idea: Wouldn't it be nice to search for any kind of music just
by your mood? - e.g. for depressive guys: fast music (hardcore), if your
girlfriend comes around: slow, silent classic, whatever you might think of.
How to accomplish that? Well, extract/sample the amplitudes in different
frequency areas (e.g. 1kHz, 5kHz, 10kHz, ..., 20kHz) at discrete times like
every half second and store these tupels in the database. Then use standard
SQL AVG and STD (standard deviation) and compare the gathered results
against user-defined thresholds.
Now, I'm looking for a software which is able to extract these sample
information and outputs them in some parsable format, a CLI Linux/Unix OS
program would be great. Does anybody know a program is capable to
accomplish that?

This sound a lot like a phase vocoder analysis program. There exists
many programs like this. An example is the old pvanal program whose
output normally is used for resynthesis by the Csound sound synthesis
program (http://www.csounds.com/). Pvanal is distributed with Csound.

A description of the file format can be found here:
http://www.ee.columbia.edu/~dpwe/resources/pvanal.html

Links to several more command line phase vocoding programs can be
found here:
http://linuxsound.atnet.at/one-page.html#dsp