The University of Arizona

Webcam

Technical Details

Here are some details about what happens behind the scenes to bring you images from the Arizona Webcam.

Hardware

Our camera is a Stardot Netcam Megapixel. The camera has an ethernet port and connects to our internal network.

Temperature data comes from the Atmospheric Sciences weather station just east of our building. We now use the five-minute-average of the ground-level temperature, the official reading from this station. National Weather Service data is used as a backup when the campus data is unavailable.

Our webserver (www.cs.arizona.edu) is a custom Opteron system running Apache software atop the Linux operating system.

Installation

The camera is mounted on a movable wooden platform that has been placed in the window of a ninth-floor office. To minimize reflections, the lens is as close as possible to the window. The camera plugs directly into the departmental network.

far view

The Gould-Simpson building from afar, with the camera location marked.

near view

A closer view of the building.


office

Inside the office looking out.

camera

The camera on the window sill.


Software

The camera is controlled by a collection of locally written Unix shell scripts. These scripts fetch an image from the camera and then use the ImageMagick and NetPBM tools to resize and enhance it and add the logo and text. The scripts are scheduled automatically using the Unix cron utility.

Once a minute, the webserver gets the latest image from the camera, adds the logo and text, and puts it on display. Once an hour, the image goes into the weekly archives.

Movies are produced nightly by another script that combines images collected throughout the day.

Recommendations

If you want to set up a webcam of your own, here are some suggestions.

Unless you prefer to roll your own software, as we did, look for a package that includes good software that's compatible with your webserver.

Camera quality and price vary over a wide range. A good camera capable of 24/7 networked operation costs much more than a mass-produced digital consumer camera of the same quality.

Camera placement is important. Find a nice view, but be sure that the camera never looks directly at the sun. Many cameras have an internal filter that can be permanently damaged by viewing the sun for long periods. Even if that's not a problem, the sun will overwhelm everything else and produce a washed-out image.

We don't worry about privacy issues because individuals seldom appear on camera and they're never large enough to be identified. That could be a concern in other circumstances.


The Computer Science webcam is run by the .