Written by Mauve of irc.mizuumi.net
The FrameDisplay tool allows you to view the character's frames of animation and overlays visual hitbox data on top of the frames. With this tool you are able to view individual frames of animation, scroll through frames, and even auto-play animation loops. The tool also comes equipped with the ability to toggle the alpha channel, the box perimeters, and the background gradient.
The Green boxes represent a hittable box. The Grey box represents A collision box (character collision boxes won't overlap). And the Red boxes represent the attack box (hitbox).
Hittable boxes and Attack boxes aren't and they can pass through one another, though obviously an attack box will "hit" a hittable box and inflict damage. The collision boxes for the characters are solid and two collision boxes can not overlap.
For details on how to control the switches and frames while using the tool, please read the framedisplay.txt that comes with the download package.
You can download the tool here. Current version: 0.1 (last updated 12/30/2008).