How to make a simple audio oscilloscope?

HolgiB · Post by **HolgiB** » Wed Jan 24, 2007 9:51 pm

I am working on an audio player application for the PSP, based on SDL.

It would be nice to have something moving in the player GUI. So my idea was to integrate a kind oscilloscope like many player apps have.

I googled a lot but still not found a small example or informations about something like that can be realized.

Anybody here can tell me something about this or where I can find a good example?

Holger

groepaz · Post by **groepaz** » Wed Jan 24, 2007 11:08 pm

thats pretty trivial, something like that:

for(i=0;i<size;i++)
{
putpixel(i,halfsize+(audiobuffer/somefactor));
}

do that after every swap of the audio buffer and you'll get something like the scope visualisation in xmms/winamp

HolgiB · Post by **HolgiB** » Thu Jan 25, 2007 12:23 am

Thank you! I was already looking at Fourier which looked way to complicate for me :-).

This looks really easy. So I will have to experiment with the values a little to get a good result.

Holger

groepaz · Post by **groepaz** » Thu Jan 25, 2007 8:14 pm

hehe...the fourier transformation you would need to do an "equalizer" type of visualisation. (although if all you want is visualisation you can get away with simpler, not terribly accurate, stuff)