Using Your Digital Camcorder as a Webcam

Using Your Digital Camcorder as a Webcam
by Andrew Alexander

Continuing in a series of one frequently asked question every day until Christmas, we come up with one of the more regular questions on the message board. This is actually a really interesting question with a highly unsatisfying answer. Since I’ve built up the disappointment, I’ll cut to the chase and then explain why afterwards. The answer is that you can’t easily use a miniDV camera as a webcam. Now I’ll tell you why.
The feature most common among miniDV cameras is the port which you use to attach it to your computer, known as a DV port (digital video) and by many other names, such as "i.Link", "firewire" and "IEEE1394", all referring to the same technology. When you connect your camcorder to your computer, you are using this firewire connection to stream the video and audio signals onto your hard drive. This is done by use of a Windows technology known as WDM ("Windows Driver Model"). WDM is a relatively new system meant to replace VfW ("Video for Windows"), the previous standard for importing and converting video from one source to the computer.

Unfortunately, most webcams and webcam programs need VfW to work, and firewire uses WDM, not VfW. Windows has in its programming a facility to translate a VfW program to output WDM, but not vice versa, so when you fire up your webcam program, the odds are it will not recognize your miniDV camcorder, connected by firewire.

So how can you make it work? Get an analog video capture card, such as the Matrox eTV G450, or an ATI Radeon with video capture, or Hauppage WinTV. All these cards use a VfW device to capture video and should be recognized in webcam software. Otherwise, invest a couple of bucks into a USB webcam.