GIFs standard is awesome, it is that most of the software does them wrong. To recap:
You can update multiple rectangles each with 0ms delay. Issue is that most browsers don't like dealing with 0ms updates, and will consider rectangle update a frame update. Some browsers will silently increase delays. [1]
You can pause once all necessary rectangles for frame have been updated. [2]
You can have full colour image provided that it is built from multiple rectangle updates, where each rectangle contains its own colour map. [3]
You can update multiple rectangles each with 0ms delay. Issue is that most browsers don't like dealing with 0ms updates, and will consider rectangle update a frame update. Some browsers will silently increase delays. [1]
You can pause once all necessary rectangles for frame have been updated. [2]
You can have full colour image provided that it is built from multiple rectangle updates, where each rectangle contains its own colour map. [3]
[1] : Browsers not respecting GIF rectangle update delays : http://nullsleep.tumblr.com/post/16524517190/animated-gif-mi...
[2] : gifsicle [image] --delay [delaytime] #[start]-[end] : http://linux.die.net/man/1/gifsicle
[3] : True Colour GIF : http://phil.ipal.org/tc.html