Heat Map

File: heatmap.php
This visualization tool will create a heat map from a list of provided points. It's written in PHP, although some of it is just pseudo code that you'll need to modify for your purposes. I've used this to visualize web site page clicks, in which case the clicks are logged using JavaScript, sent via AJAX, and stored in a database. I then use CSS to make the image semi-transparent and to place it over an iframe of the page. Note, this code is rather slow for a large image and/or a large number of points; you would probably get a big performance increase by writing this in C and calling out to it.

Feel free to contact me with any questions.