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Nemesis a complete Linux video security system. It s idea is a cheap replacement for your commercia

Nemesis V0.0.1 ALPHA
http://www.inodes.org/nemesis

About

	Nemesis is a complete Linux video security system. It's idea is a
cheap replacement for your commercial video system that can retail from a
total of $15,000 up. Well that's what they quoted me before I decided to do it
myself.

	This is an initial ALPHA release to get some ideas on improvements that
I can make etc. Also people that like my idea have been bugging me to release
it. The next release will most likely be a total rewrite since I'm not happy
with how all the modules fit together at the moment. There's not much really
holding everything together.

Minimum Hardware Requirements

	Well I'm not really sure, I need some testers to try and work this out
:) 

	* Video Capture Card - streamer uses video for Linux which is now
	     supported by the Linux kernel to do it's capturing. This means
	     there are a fair amount of ways to capture data ranging from a
	     quick-cam plugged into your parallel port to a card with a bt848
	     chipset in a PCI slot.
	
	* Video Camera - If your using some sort of bt848 chipset card like I
	     am you'll need a video camera. I'm using a simple little CCD
	     camera that gives me video out plugged straight into the back of
	     the card.

	* Copious amounts of hard disk - I'm using JPEG compression to store
	     the images. With a B&W camera at 320x200 this equates to approx
	     13k per image. I find that recording at 5 fps is adequate for my
	     environment so this equates to about 220 Meg an hour, or 5.2 Gigs
	     for 24 hours worth.

	* CPU - The machine I'm running on is a Celeron 300A. This seems to be
	     adequate. It will even p[lay mp3' while it records :) The whole
	     recording process is not really CPU intensive it's more a disk
	     speed issue.

	As you can see there's not really that much that you need. All up a
full system cost me $1700 for a full installation. This probably equates to
about $1000US. 

What does what?

	The main executables that do all the work are 
		- streamer, and
		- vplay

	streamer does the actual video grabbing. It's a highly adapted version of
Gerd Knorr streamer that comes with xawtv. 

	vplay is used for playback of the recorded images. It has a simple
interface that lets you playback the saved video from anytime within the last
24 hours. It also lets you save the current image to a floppy or a directory
on the hard disk.

Some Useful Scripts

	At the moment the system is glued together by a couple of perl scripts

	start_hour.sh - I put this script in my crontab and run it every hour. This 
			is because currently the directory images are placed in is 
			decided by the time of day the next script starts. This kludge
			will be improved in future version.

	stream.pl - This is the script that does most of the work, passing the
		    appropriate arguments to streamer, changing to the right
		    directory etc

	restart.pl - You can run this to restart, streamer, since it does a
		     killall first in case it hasn't died properly.

Current Deployments

	I have a system currently using all this software already in
production in a hotel in Sydney, Australia. To give it some sort of full
proofness, ie you don't have to know anything about Linux to use it I've done
a few things to simplify matters.

	First of all I've tied to vplay to a button in my favourite
window manager so that the player can be easily started to see if anythings
happened and I have restart.pl tied to a button to restart the recorder in case
it stops for some reason.

	I have set the machine up so that rc.local runs startx. Yes this is
evil but if the machine crashes etc I want it to come back up in a sane state
without anyone having to log in. It actually runs startx in a while loop so
you can kill the X server with ctrl-alt-backspace if things really go wrong.
Then I put start_hour.sh in a crontab so the recorder keeps running.


	Of you have any suggestions, improvements, patches etc please e-mail
me at [e-mail].

John Ferlito
[e-mail]