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Exposing Yourself to the Web

by Larry Gilbert

What would George Orwell think? One chilling prophecy of his most well-known novel, 1984, has come true within 11 years of the time it portrays. Television cameras, linked by a global electronic network, peer at streets, offices, and households throughout the world--and more are being linked up every day.

However, that probably wouldn't have surprised him as much as the fact that anyone is allowed to take a peek through these digital port-holes. And what would he make of the reasons why more and more people are willingly making these cameras available: admiration of parrots and fish? remote operation of model railroads? monitoring of a coffee pot across the building (or across the Atlantic)? sales of chia planters?!

The World Wide Web has spawned a curious Internet-wide fad: ``Web cams''. And curiosity may well be what keeps the idea going. Browsing a list of such cameras is like being a virtual tourist or (some might accuse) a Web voyeur. While it may take a bit of an intuitive leap to think of a Web page as being somewhere else in the world, having an up-to-the-minute snapshot on the page drives the point home to anyone. How else can one explain the fascination with gazing at a bus terminal in Berlin, mountains in Norway, an iguana cage in California, a home office in Texas, or a total stranger's feet in the UK?

You who are reading this magazine may already be caught up in this fad, looking to get in on it in your own little way. That's what this article hopes to help you do, first by summarizing what makes a Web cam tick, then by pointing you toward more specific information available on the net.

Methods To The Madness

People open up their vistas to the Web for many reasons. Some of the main ones:

Utility

This is how the original Web cam got its start--and it wasn't even on the Web. In 1991, people working at the University of Cambridge Computer Lab pointed a camera at the lab's coffee pot, hooked the camera up to a computer with a video capture board, and set it up to act as an image server. Thus anyone in the building on the lab's network could see the status of the coffee pot without needlessly traipsing up several flights of stairs for a caffeine fix. The camera actually didn't appear on the Web until much later, but as near as anyone can tell, it is still the first and most famous. (Quentin Stafford-Fraser has written an amusing history of the coffee pot.)

Promotion

This is the most popular reason for setting up a Web cam. A number of hardware manufacturers and Internet service providers use their cameras as a draw for their other pages in order to hawk their goods. Some tourist spots (such as the Rhonda Smith Windsurfing Center on the Columbia River Gorge) have cameras set up to let people marvel at the view. A novelty company in California even trained a camera on one of its chia planters, presuming people would sit and watch the thing grow (perhaps someone does).

Self-expression

Like wearing a loud tie or festooning your car with plastic toys, setting up a unique Web cam is a good way to attract attention, for better or worse. I can think of no other purpose for things like Nick's Feet Cam in Great Britain or the ``ShuttleCam'' that Dr. Ritchey Ruff set up to display the status of the model dangling from his office's ceiling.

Philanthropy?

The spirit of generosity that permeates the Web may inspire you to set up a camera of your own. Even now, you may be saying to yourself, ``By golly, I want to give something back to this wonderful virtual community! I'm going to point a camera at the moldy pickles in my fridge and hook it up to the Web for the whole world to see! But... where do I start?''

Four Steps To Becoming A Web Exhibitionist

Assuming you've already decided on your planned Web cam's purpose (or lack thereof), setting it up involves tackling four main problems.

1. Finding a camera
Having a video camera is a rather important requirement. If you are lucky enough to have a workstation with teleconferencing capability already set up, then half your work is already done (assuming you want to broadcast your stony staring-at-the-CRT face to the computing world at large). You may also have the good fortune of working for a company or institution with a security camera located somewhere interesting. Then, if you're persuasive enough, you might be allowed to tap into the video from that. But the odds are getting a camera will be your responsibility. A consumer-grade camcorder should work fine, and is much cheaper if you happen to own one already; you might even want to use the time-stamp feature to give your live shot a smidge more authority. You could do the bargain-hunting thing at a used camera shop, but bear in mind that an older tube-based camera may not enjoy being left on full-time and will eventually burn out; newer CCD-based cameras are more durable in that respect. In any case, take care that the output from the camera will be standard enough to match the input on your video capture device (see the next step). One inexpensive alternative for Macintosh users is the Connetix QuickCam, a small camera that requires no additional video hardware. It has been used successfully as a Web camera, but the picture is small and in black-and-white--less than ideal for things like showing off that booming organic vegetable garden.

2. Getting video into your computer
Once you've found a camera with standard video output, you'll need a video capture device or ``frame grabber''. As mentioned above, some cameras don't require one, but most do. Some lucky people, like those with a Macintosh Quadra AV or an SGI Indy, don't have to worry about this part--they've got video inputs built into their machines. But the rest of you need not panic; frame grabbers are easy to find at most computer stores, some as low as $200. They're available from a number of manufacturers, including Creative Labs, Vigra, Radius, Play, and others.

3. Getting it on the Web
Once you're finished setting up your hardware and expending your Visa card, you'll have to get your computer to grab a video image from your camera and store it at a regular interval. Then the image has to be stored as a GIF or JPEG on a public HTTP server if anyone's going to look at it. (Setting up an HTTP server is a matter for another article, but there's plenty of information about that on the Web already). [And coming up in this magazine. -Ed])

One of the most commonly-used setups works this way: A script (or batch file to you DOS heads) executes the appropriate frame-grabbing utility, runs a conversion utility to go from the frame grabber's image format to GIF or JPEG, copies the final image to an HTTP server via a local network connection, and the whole process repeats after a time. This process allows a low-cost computer to act as a dedicated camera server and lets the big, powerful HTTP server handle all the image requests. It is also a good setup choice when the camera is on a remote computer with no connection to the outside world other than PPP or SLIP (in that case the camera server has to do a dial-up and a login every time it has to copy an image). If the computer with the camera is powerful enough, and if it has a high-speed net connection, it can act as the HTTP server itself. Then, instead of linking to a stored image file, the camera link on your server can link to a CGI script that grabs a video frame and converts it on the fly, providing a truly live snapshot. (Got that?) If you wanted to get really fancy--and if you don't give a rip about browser compatibility--you could take advantage of ``client pull'' or ``server push''; on browsers like Netscape Navigator to provide continuous, albeit painfully s-l-o-w, real-time video. Cool.

This sounds like a lot of work, but at this point you have yet to solve the toughest problem of all...

4. Explaining all this to your friends and family
Yes, it's likely that most people in your life just don't understand what the World Wide Web is, let alone why you might get excited about hooking all this equipment up to it for no apparent reason other than to let others invade your privacy. How might you sum things up for them in a nutshell? Here's some ideas for what to tell them:

Wherever George Orwell is, you're giving him something to laugh about.

Larry Gilbert is a technical support person and computer geek at-large who lives in Seattle. He spends too much of his free time trying to maintain his own list of Web cams (http://www.eskimo.com/~irving/web-voyeur/) , and can be reached via e-mail at irving@eskimo.com

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