ubuntu: install driver for webcam

* depending on what webcam do you have, you need to install the corresponding drivers (UVC, gspca, sq930x, etc.)

* first, I install UVC driver but the /dev/video0 is missing; later I realized that it is because UVC does not support my webcam.

* in my case, I have to install gspca drive and need sq930x to support the Creative Lab Live Ultra webcam. The guide to install the driver gspca here (the summary in clipmarks.com)

* now I can use guvcview to open the video; or open the video stream by OpenCV
File: test_webcam.py

#!/usr/bin/env python
# 29.April.2011
# test the webcam in Ubuntu
import cv

cap = cv.CaptureFromCAM(0)

win_name = 'video'
while True:
	frame = cv.QueryFrame(cap)
	cv.ShowImage(win_name, frame)

	c = '%c' % (cv.WaitKey(10) & 255)
	if c in ['q', 'Q', 'x1b']:


Example of an image