[PD] Seam carving audio

Mathieu Bouchard matju at artengine.ca
Tue Jul 8 08:53:56 CEST 2008

On Mon, 9 Jun 2008, Chris McCormick wrote:

> Something struck me whilst out walking today; has anyone applied the
> seam carving technique:
> <http://en.wikipedia.org/wiki/Seam_carving>
> <www.youtube.com/watch?v=6NcIJXTlugc>
> to FFT data to do a timestretch/timecompress that is more sensitive to
> attack sounds and note lengths?

I doubt that this would work at all. It's already of dubious use on 
images, as it introduces distorsions that even though they are made to 
look least like distorsions, are serious distorsions anyway, and can mess 
up the perception of the content seriously. Compared to the "deleting 
least important columns" technique that they show at 1:40, the Seam 
Carving technique sweeps the distorsions under the carpet. After that, 
don't wonder what the big lump under the carpet is.

When applying the technique to the spectrogram of a song, you should hear 
it many times more than you'd see it.

Perhaps it can be used as an interesting special effect, supposing that 
what you want to do is mess up the rhythm seriously and turn chords into 
arpeggios in truly weird ways. However, it will work at the sine wave 
level, which is somewhat less attractive than if it worked on notes.

Instead of applying it on FFT, you could apply it on a piano roll. (A real 
one, unlike GridFlow's patch of that name, which is actually botched FFT 

  _ _ __ ___ _____ ________ _____________ _____________________ ...
| Mathieu Bouchard - tél:+1.514.383.3801, Montréal, Québec

More information about the Pd-list mailing list