USB Webcams on Linux

While trying out various webcams on Linux, we found that the setups could vary considerably depending upon the webcam you use. The basic procedure remains the same, which includes downloading the webcam drivers, compile them, which will usually result in a kernel module, loading the module, and finally accessing it through /dev/video0 using any suitable application.

Logitech Quickcam Express



Download the drivers for Quickcam Express from http://prdownloads.sourceforge.net/qce-ga/qce-ga-0.40b.tar.gz. Extract the archive as:





tar —zxvf qce-ga-0.40b.tar.gz

This will produce a directory ‘qce-ga-0.40b’. Change to this directory and issue the command:

ln -s /usr/src/linux- 2.4.2 /usr/src/linux

make

The ‘make’ command will produce a file named mod_quickcam.o. This file is the kernel module for Quickcam Express. Copy this file to /lib/modules/2.4.2-2/kernel/drivers/usb directory. Restart the machine. Log in as ‘root’ again and issue:

modprobe mod_quickcam

Plug in the Logitech Quickcam in the USB port. Subsequently use applications like XawTV or Gnomemeeting to use the

camera. 

IBM PC Camera



The kernel module for IBM PC already exists in PCQLinux 7.1. So setting this up is just a matter of loading the module using the command:

modprobe ibmcam






and plugging in the camera to the USB port. 

Prolink Webcam



The Prolink webcam is based on a chipset called CpiA (Color Processor Interface ASIC). The module for such USB webcam already exists in PCQLinux 7.1. Also upon detection of such a cam plugged in, the corresponding module is automatically loaded. Thus we needn’t load it using the ‘modprobe’ command as in the case of IBM PC Camera. 



While there are so many other webcams in the market, we looked at some popular ones to give you an idea of how they can be set up on Linux. Besides following the steps we outlined, you just need to do a little bit of searching for drivers and going
through some ‘readme’ files. 

Shekhar Govindarajan