gzthermal compression visualization

Neat little tool: gzthermal-web, which visualizes the efficiency of compression from gzip. Each byte is colored depending on how well it compresses; dark blue for 1 bit up to red for 9 bits. It’s a wrapper for the gzthermal tool, as discussed on Hacker News and in this sort of odd article. (Undocumented feature; append &w=1 for a wider image.)

Here’s my weblog visualized with it, sorry for the giant long image. It looks better if you view the image alone shrunk-to-fit.

Structure is clear. The bright yellow parts are inlined PNG images which won’t gzip very well since they’re already compressed. The dark blue chunk at the front is my calendar, a bunch of stupidly repeated HTML. Blog posts are the motley blue/green patches separated by the dark blue of the HTML boilerplate between blog entries.

I’m not exactly sure how I’d act on this information. But it looks neat!