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Fun with video effects on Linux

Occasionally, your editor stumbles across some really fun software in the tireless search for interesting Linux applications. It all began with the recent acquisition of an inexpensive Kensington VideoCAM USB camera from a yard sale. This was my third yard sale camera purchase in the summer hunt for fun computer toys, it was also the first camera that I actually managed to get working under Linux. [Kensington USB Cam]

Previous attempts to get a Kodak DVC-323 cam (unsupported) and a Connectix parallel-port Quick-cam (supposedly supported, but broken) proved to be more trouble than they were worth. Unlike the other devices, the Kensington camera provided a pleasant hardware experience. It works well with most of the video applications that I have experimented with so far, and did not require a kernel build to use. The Kensington camera is not a super high-quality device, with a maximum 300x400 resolution and a total inability to handle the brightness levels found outdoors, it is mainly useful for indoor use.

Fun Video Applications

We'll take a look at a couple of interesting video applications for Linux, to see the wide variety of video applications that are available, search the FSF/UNESCO Free Software Directory and GnomeFiles sites.

The application xawtv seems to be the basic video application for X11 systems. It has a useful -hwscan (hardware scan) mode that can locate active video devices. Xawtv is useful for getting a quick video display up and running, focusing the camera, and adjusting the brightness and color balance levels. Xawtv is also useful for grabbing snapshot images, it advertises the ability to record movies, but your editor was unable to make that work. After verifying the basic functionality of your camera, it's time to move on to more interesting applications.

Mvc, the Movement Video Capture application is an interesting application that can be used to capture movement within the camera's field of view. Mvc is a tiny package that built with no problems on my RedHat 9.0 and Fedora Core 1 systems. Operation is simple, just fire it up and it will create a series of .jpg images as it detects motion. Denizens of cube-farms may find it useful for figuring out who is making off with your pencils when you are away.

EffecTV is by far, the most interesting video application that I have found: "EffecTV is a real-time video effector. You can watch TV or video through amazing effectors." The current version features 39 real-time video effects. Some of the effects are fairly simple, such as adding noise and distortion to the video, changing colors, and producing both sides of a mirror-image. Other effects are quite impressive, such as viewing through real-time morphing lenses, through-the-water simulations, and burning simulations. A number of the more complicated effects are quite subtle, you may want to leave them on for a while to get the full effect. Effectv also has a few trendy effects, such as Warhol TV, Shagedelic TV, and Matrix TV.

To switch the current effect, simply press the keyboard's up and down arrow keys. A GUI interface with buttons for each effect, and sliders to modify the parameters would be a useful addition. The effectv full-screen mode is the best way to get the most bang-per-buck from even the cheapest of video cameras. It is a bit too easy to get stuck in full-screen mode, pressing alt-enter toggles it on and off.

Below are a few still shots from some of the many effectv modes, keep in mind that they hardly do justice to the real-time video-in-motion:


Chameleon Effect	Vertigo Effect

Warhol Effect	Warp Effect

Not being easily satisfied, your editor procured a second Kensington camera on eBay for a mere 99 cents (before shipping costs). As a fun demonstration, I connected both cameras up to the USB ports on my Athlon XP1700 system, then fired up XaoS, a real-time fractal zoomer that's worthy of note. With a little effort, I was able to fill the entire screen up with three windows worth of zooming fractals and morphing video effects. Such a system would make a great store-front display, or could provide some fun interactive eye candy for your next party. This is a great way to put some of those idle processor mips to use. It must be time to look into getting one of those fancy high resolution video projection devices...

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