V4L capturing

There is several applications for continuous pictures capturing (e.g. for web, emailing)

• webcam
• streamer
• videodog

Common configuration and control commands

1. Control the TV card (v4lctl is a part of the xawtv package)

• v4lctl -c /dev/video0 list
• v4lctl -c /dev/video0 bright "60%"
• v4lctl -c /dev/video0 contrast "55%"

2. Capture the snaps (streamer is a part of the xawtv package)

• streamer:

Usage:

streamer -i 1 -c /dev/video0 -s 320x240 -q -j 80 -f jpeg -n ntsc -b 24 -o /var/www/webcam.jpeg

streamer -i 1 -c /dev/video0 -s 320x240 -q -j 80 -f jpeg -n ntsc -b 24 -o /dev/stdout |uuencode thief.jpeg|sendmail alarm@foo.com

• videodog:

Usage:

videodog -x 640 -y 480 -w 3 -b 1 -c 65535 -m PAL -q -d /dev/video0 -j -f /var/www/webcam.jpg

• webcam:

This useful tool supports continuously moving (ftp or scp - ssh copy) of jpeg output to remote server. Also allows put in additional text (date time, location), rotating of image.

Usage:

webcam /etc/webcamrc

Image format information

Good place to look is http://www.fourcc.org/

About philips webcam compression format good info and free decoders can be found on http://www.saillard.org/linux/pwc/