Take one digital video capture card, a big cheap hard disk, a home-brew infrared receiver, and a seven-year-old PC out of your nearest closet or dumpster. Add some free software and-voila!-you have a personal video recorder, your own homemade Tivo. As with Tivo, watch what you want, when you want. Thumb your nose at the head of Turner Broadcasting or whoever else is angry that you have broken your "contract" to sit through commercials and are "stealing" programming if you don't. Know that you have built this insidious entertainment appliance yourself.
Which you can do if you're literate enough to run a few basic Web searches, do not run for cover at the mention of Linux, and know which is the business end of a Phillips-head screwdriver. Of course, you could buy a similar personal video recorder (PVR) unit from Sony or Philips or Sonic Blue. Or wait for your cable company to install one. Or buy software from Snapstream or Showshifter or one of the other companies that's sprung up to let you convert your new $1,000 PC into a good imitation of a $200 VCR. But where would be the fun in that?
Klaus Schmidinger runs a small software company about an hour from Munich. He and 90-odd of his closest friends on the Net have spent thousands of hours-"Do you ever sleep?" asks one e-mail correspondent-developing open-source software, and a little bit of hardware, to let any Linux box record and play back digital TV signals (for an overview and the download, go to www.cadsoft.de/vdr).
You can do all the things you can do with the commercial versions, such as scrolling through lists of programs and selecting the ones you want. Plus, you can make new copies of recorded programs with the commercials edited out (or, for that matter, create video files with nothing but commercials). And if there's a feature you want that's not there, you can fire up a text editor, rewrite the code, and fix it.
For now, whatever you do with your Linux recorder, with the exception of rebroadcasting or selling digitized shows, is still mostly legal. That may change (in the United States at least) if entertainment industry lobbyists get their way: On tap in the current Congress, for example, is one bill that would require any digital device capable of storing copyrighted material to abide by whatever restrictions publishers decide to impose on how the material can be viewed, played, or copied. Another would permit registered copyright owners to hack into any computer they believe might be involved in illicit reproduction of their property, to prevent that computer from sharing the owners' copyrighted material. The move to increase the power of content publishers has raised the ire of the Electronic Frontier Foundation (www.eff.org), a nonprofit organization that battles restrictions to Internet information flow.
When he started the project back in late 1999, none of these issues really occupied Schmidinger's attention. The idea of competing with the newly introduced Tivo or ReplayTV machines wasn't important back then either, he says, although now he's glad to have built a PVR that can't be silently "up-graded" by the manufacturer to record shows you would never ask for or to record every button you press, for evidence in a lawsuit.
Schmidinger was working on a completely different hobby project-building a personal full-motion flight simulator-when he read in a German computer magazine that a couple of enterprising brothers, Marcus and Ralph Metzler, had written a Linux driver for a digital video card.
Five months later he had a prototype that could record video and play it back. Forty versions and two years after that, the first "official" version was done. Download it, compile it, install it on your Linux box, and the catchily named "vdr" program will help you build a list of programs to record-with priority rankings in case more than one show you want is scheduled at one time and you don't have multiple video cards. Then whatever you can fit on your hard drive at the rate of 2GB per hour of video is yours to do with as you please. (VDR is the acronym for video disk recorder, which is what Europeans call our personal video recorders. Transatlantic incompatibility lives on.)
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.