#! /bin/sh
#Motion detection script for use with Nemisis Linux video capture program.
#Written by David Bowler 7 Sep 2000
#Require packages:  	Nemisis http://www.inodes.org/nemesis
#			netpbm ftp://metalab.unc.edu/pub/Linux/apps/graphics
# This script may be freely copied and modified

STREAMER=/usr/local/bin/streamer
RESOLUTION=480x360
DEVICE=1
FRAMERATE=1
SENSITIVITY=30
PNMPSNR=/usr/src/netpbm-9.6/pnm/fiasco/pnmpsnr

$STREAMER -s $RESOLUTION -i $DEVICE -o /tmp/image.jpg
djpeg -scale 1/4 -ppm /tmp/image.jpg > /tmp/image.ppm
while true
do
sleep $FRAMERATE
$STREAMER -s $RESOLUTION -i $DEVICE -o /tmp/image2.jpg
djpeg -scale 1/4 -ppm /tmp/image2.jpg > /tmp/image2.ppm
date>/tmp/Ycolour
$PNMPSNR /tmp/image.ppm /tmp/image2.ppm>>/tmp/Ycolour 2>&1
Y=`awk '/Y  color/ {print int($4)}' /tmp/Ycolour`
if [ $Y -lt $SENSITIVITY ]
then 
cp /tmp/image2.jpg `date +%m%d%H%M%S.jpg`
fi
mv /tmp/image2.ppm /tmp/image.ppm
done