Videoconferencing for Linux

Plugging video into the Linux desktop, whether for a webcam or for use in videoconferencing/videophone, is still something of an adventure. But like most Linux configurations that are still a bit problematic, with the right tour guide, it's almost a walk in the park. This recipe aims to be that guide.

Though videoconferencing/videophone is harder to set up on Linux than it is on Mac or Windows, it's still a useful tool, and an alternative to Vonage and Skype. In general, videoconferencing works best (or at all) when using the same client, including versions running across platforms.

For this recipe, I recommend using a telephone-style headset to work through this piece with. But even then, feedback between a microphone and speakers will be difficult to avoid. You can use headphones if you're using a digi/webcam microphone, but your sound quality will most likely be better with a microphone in a headset assembly.

Though I used the Debian Linux distribution, Ubuntu users should be able to use the same instructions. If you aren't using a Debian-based distribution, you should use the instructions for automated installation (for example, yum install filename for Fedora/RHEL) or the installer GUI that works with your distribution. The program filename should be the same.

Video4Linux (v4l, v4l2 - gspca)

This is the basic building block underlying most Linux video applications.

The first step is selecting a webcam with a Linux driver.

Compatible USB (only) Videocams

You can find a list of cameras with compatible drivers here.

This is a good place to use your Web browser's page search feature—usually, control + F—to look up model names or USB ID codes. My camera is an inexpensive Aiptek DV4100M digicam with "live video" and flash disk storage for digital images and video.

If you have a camera you want to use, but it doesn't seem to appear on the list, plug it in and get a list of all plugged-in USB devices. Assuming it isn't a pure webcam, make sure your camera is set to "live" or "video" mode once your USB cord is plugged into the computer. If you don't have a camera already, use the list to guide you in finding a camera that will work for Linux video without problems.

Note that a

monospace

font means that this is text that should be entered or displayed via Linux terminal application. $ means do this from a user prompt, # means a root (admin) command given from a root login, a user with the root password accesses a root login by:

$ su root
Password:

To discover the USB identification information from your camera:

username@workstation:~$ lsusb
Bus 002 Device 007: ID 08ca:2040 Aiptek International, Inc.
Bus 002 Device 005: ID 050d:0551 Belkin Components
Bus 002 Device 006: ID 04a9:220e Canon, Inc. CanoScan N1240U/LiDE 30
Bus 002 Device 004: ID 04a9:1094 Canon, Inc. 
PIXMA iP3000x Printer

The first hex 4-digit number after the ID is the product ID. The second is the vendor. I'd search on product ID. If both numbers match something in the driver list, then you are in business with Linux video. If not, I recommend finding a supported camera. Either a digicam or webcam that's listed should work fine.

With a webcam, make sure it's running in the desired mode—live or disk access—to match videoconferencing or image/video retrieval from camera flash disk.

INSTALLING VIDEO4LINUX

Make sure gnome-desktop-environment (or the equivalent in your distro) is installed. If it isn't and you're using the KDE window manager as your desktop, when you install it, make sure that KDE stays the default window manager.

"Use the Source, Luke!"

If the version installed via your distro's automated installer fails, download the gspca source or, if available, a binary from your distribution from here. I'm not providing instructions for Debian, because this is one of the rare cases when building from source is actually easier. Besides, I never did get gspca-source working, as I would ordinarily install via apt-get.

If you got a source tarball (tarball file extensions are tgz , tar.gz , tar.bz2), then do this:

$ tar xzvf gspca*
$ cd gspca*
$ su root
# make && make install && depmod "ae

If this fails, open the README file in the gspca directory to see what it can tell you. If that doesn't help, go to the Where To Get Help section at the end of this Recipe.

Next, plug in the camera. Make sure that it's in "live" (or Web or video) mode with the USB cord plugged in. Not "picture" or "still" image. Get this wrong, and the camera will think it's supposed to transfer your last batch of still offline images or videos. Don't take for granted that it will stay in the mode you left it in, either. If you got it running and it suddenly fails, check this first.

$ ls /dev/vid*

You should see a video0 file in that directory. If you do, you've got video.