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Saturday August 14, 2004

iTunes Visualizer

I'm not always the quickest to get plugged in to a new good thing. Others have no doubt known about this for ~~years~~ months. Oh well. This is for the one or two of you out there who are even more temporally challenged than I am!

About three months ago I bought an iBook (which I love), and one of the applications I use the most on it is iTunes. Not for my own music collection or to buy new music from the Apple store, but to listen to some of the free Internet radio stations (one of my favorites being Radio Paradise, because the owner/DJ has such an eclectic taste in music, and you have no idea what he's going to play next).

Well anyway, I was browsing around the Apple store last night and saw that iTunes is also a free download for Windows as well as Mac. Awright! I still use a Windows box quite a bit at home, so it'll be nice to listen to my favorite radio stations as easily as I can on the iBook.

I wasn't disappointed. As this review mentions, this is a wonderful program. Playing around with the Windows XP version last night, I discovered the visualizer and got totally mesmorized by it. I spent about an hour trying it out with different types of music (and just chat shows) and watching how it visualized. It seems to do a very good job. Ambient music is obviously very different from hard rock, which in turn is very different from your favorite politicians gabbing on national public radio. I also found this page with further tips on how to configure the visualizer. More hidden features here.

So how exactly does it work? From googling around, I've been unable to find any great pointers to the actual theories and procedures behind what it does. If anybody has any leads, please let me know. Thanks.

[Technorati Tag: Visualization]

[Technorati Tag: Graphics]

[Technorati Tag: iTunes]

( Aug 14 2004, 02:06:52 PM PDT ) [Listen] Permalink Comments [9]

Comments:

You should also check out Winamp+Milkdrop for windows. I find it's even smoother and more mesmorizing than the iTunes visualizer.

Posted by Mike on August 14, 2004 at 02:57 PM PDT #

Or Winamp (or any other audio source) + R4 for some of the nicest visualisations you've seen, and a nice Open GL based scripting API to develop new ones.

Posted by Jellybob on August 14, 2004 at 04:36 PM PDT #

Talking of online radio stations you should check out Resonance FM it's London based but can be streamed online. Oh and it is very eclectic so if you don't like what you hear when you tune in don't be afraid to try another time or check out the listings. :-)

PS. You need to go on to the "listen" page to find the high quality mp3 stream, the "mp3" link next to the "listen" link on the left gives you a lower quality stream.

Posted by nrl on August 14, 2004 at 04:50 PM PDT #

The WinAmp visualiser offers a special 3D mode, the one you need those 3D glasses to see. Try it out!

Posted by Simon on August 15, 2004 at 04:37 AM PDT #

Thanks everyone, I'll checkout all your recommendations.

Posted by Rich Burridge on August 15, 2004 at 08:23 AM PDT #

G-Force
I remember this one being really, really nice, from back in the days when I used to use Windows...
Write your own 'config' files which is kinda fun.

Posted by Hal on August 15, 2004 at 09:53 AM PDT #

You asked how the visualizer works. I don't know the exact specifics in involved, but it is pretty clear to me that it is doing a realtime Fourier analysis on the audio stream, converting that to a power spectrum, and then generating various imagery that derive from the frequency vs. time data of the scrolling spectrogram. People often ignore this facet of audio analysis, thinking that all they can do is see the realtime spectrum from moment to moment, but a spectrogam is a time-based plot of one spectrum after another (several per second), so you get not only frequency vs power for an instant, but frequency vs power vs time over a time period (so a 3D plot then). Any number of interesting pattern recognition heuristics could then tease out patterns in the spectrogram and produce imagery which is coordinated with the audio stream...which in no way diminishes the itunes visualizer's beauty. I have wasted chunks of time staring at it myself. :-) Cheers!

Posted by Keith on August 30, 2004 at 03:12 PM PDT #

Thanks Keith! Recently we had a laptop shuffle in our house. My wife now has my iBook and she's given her Windows XP laptop to her mother. I got to buy a new Powerbook, which has 128 Mb of graphics memory. This beauty can get 30+ frames per second of iTunes visualization and it's made the graphics every more impressive to me then before. It's interesting that I can only get about 15 fps on my Windows XP ICE-Cube which has a P4 3GHz and an Intel Extreme graphics chip on the motherboard. I wonder whether Apple just haven't tried to optimize the graphics for the "other" platform they support.

Posted by Rich Burridge on August 30, 2004 at 06:03 PM PDT #

yes very good on the visualizer ting but most of us have known about this for ages. so anyway im not really sure how it works but i have got a lot more different visualizers from computer programmers and they seem to know wats going on. so ask the!

Posted by Justin on October 23, 2004 at 11:50 AM PDT #