[PD] audio fingerprints

[Christian Klippel]

hi david,

Am Freitag, 29. November 2002 05:30 schrieb David Sabine:
> Hello all,
>
> The past discussion on this topic has been primarily about the 'database'
> which might store the audio fingerprints.
>
> However, the initial problem is not storage or retrieval of the
> fingerprint, but what does the fingerprint LOOK like?  How does one create
> a 'stamp' or 'summary' or 'fingerprint' of a sound file?  For example, if I

there are serveral ways. i digged into that topic a long time ago when i 
wanted to restore the titles of my mp3 files. 
btw, there are some open-source tools around that do that, and can work
in conjunction with a song-database.....

first, you can count the beats in the file, secondly you can calc the number
of beats for one minute, an you can create some kind of "beat pattern" to
identify it. but thats not enough. you should also capture the avareage 
energys in specified frequency bands. you can also extract a pattern out
of this to analyze sound material. for example, like : "after two times of
high mid-frequency energy follow 3 times of low freq and one high freq"
also the average loudness of a sound (also in "patterns" of serveral seconds
each) can help. other characteristica may be the distribution of loud and
silence phases in the material.

give all these "parameters" a weight, and such "fingerprint" where the most 
parameters are around the same weight's probably is the right one decribing
a actual fingerprinted song.

> Regards,
> Dave S
>
>

greets,

chris