The featured visualization plugin on Winamp last month was the Advanced Visualization System 2.x or just AVS.

If the plugin model has done anything, it has provided a small doorway for powerful software to be made available for free. AVS allows you to "roll your own" visualization using a variety of effects. You can add AVI's, images, text, and all sorts of render and transformation effects, most of which have beat sensitivity.

Documentation

For a quick introduction to using the effects in AVS, check out Nullsoft Developer Network's AVS Developer Docs. The documentation is a bit sketchy right now, but it's being worked on.

The documentation gets you familiar with the interface, but there is little on the effects themselves. Your best bet is to just play with them to see what they do, and examine the presets that come with AVS to see how it is they accomplish what they're doing.

Functionaility

There are basically two things you can add to create a vis - "render" and "trans" (transformations.) Render displays objects on the screen, such as AVIs, pictures, text, or generated effects like scopes, spinners, dot fountains, whatever. Transformation effects the rendered objects by changing color fading, bump mapping, swirls, warps, rotations, etc. Many of the trans and render effects are beat sensitive. Almost all the effects are totally customizable, from changing the color, to writing trigonometric functions to manipulate their behavior. The are also "APE"s, which are external plugin effects for AVS. There's currently a fireworks effect and a static tv-like effect available as APEs. APEs allow third party programmers to add effects to AVS. Plugins for Plugins. You can also allegedly load Sonique (another mp3 player) plugins into AVS using the SVP loader.

To get it to list your avi's in the dropdown box in AVS you need to copy your AVI's into the C:\Program Files\Winamp\PLUGINS\avs directory. In order to switch the avi files on the fly, you have assign separate hot keys with the same effects but a different avi. Unfortunately, there is no luma or chroma key in the program.

If you use the rend.>picture, the picture needs to be in .bmp format and it also needs to be in the avs folder.

Using Line Input

I initially had a difficulty trying to get Winamp to accept line input. Most AVS effects do nothing at all until they're being feed an audio stream, and from a VJ perspective, Visualizing to MP3s is about as cool as masturbation. To get winamp to render vis effects from a line input, press "Ctrl+L" to play a location, and enter "linein://". In addition, you have to select "Microphone 1" in the "Recording Control" window of "Volume Control". I also had a problem where I had to have a CD playing before beat detection triggered from the line input. I tested it out and it definitely was triggering from the mic and not the CD, but the CD still had to be playing. To solve this I set winamp to auto-repeat.

Beat Detection

The beat detection seems to react to high freq's rather then the low freq's, ie it seems to follow the hihats rather than the bass drum. It also has a max bpm detection level of 140, so it doesn't work very well when used for happy hardcore and the like.

Speed

The program does have some speed issues. Running 640x480 fullscreen at 16bit on a Asus V6600 Deluxe Geforce, Celeron 300a@450mhz, 160mb ram, Wide SCSI HD, I couldn't get much more then 22 fps, even using the built in presets. Running avs on a PIII 500mhz "512k burst cache", ati 16mb with openGL, and direct 3d, 64mb ram, win 98, it just bearly ran at 30fps on the simple presets. The Pixel Doubling feature does help the fps rate quite a bit.

Tips

I had some fun using the "webdings" font with the text renderer. Another trick is animating text the old fashioned way. Pick a monospace font ("courier new" for example), and pick a window of how many characters you want to animate. For example, if I wanted to scroll my name across the middle of the screen showing 8 characters at a time, I'd do something like this:

C; CR; CRO; CROS; CROSi; CROSiS; CROSiS ;CROSiS ;ROSiS

Now put it centered on the screen. because i've selected a monospace font (where every typed character is the same width), and each piece of text is exactly 8 characters long (notice the padded spaces), it will march across the screen to the beat. Get creative. You can scroll, wipe, or whatever.

More Eyecandy

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