Random Thoughts

The other week I was tinkering with editing GIF animations in Emacs, and then I started wondering: Can this be any more ridiculous?

Yes.

So it’s a mashup of the Emacs meme mode and the new GIF animation code.  I spent most of the time on this wondering whether I could somehow make one or the other a minor mode before giving up and just mashed the code into meme.el, which can be found on Github.

The main challenge here was figuring out how to make this fast enough.  The first naive implementation just created an SVG 25 times a second with all the data in it, and Emacs just isn’t fast enough to print a ~2MB XML structure that often.  (Not to mention when animating bluray screen grabs: The SVG structure is then about 7MB.)

So I cheated and pre-computed the screengrab bits, and then plonked down those bits into the printed XML structure.  Which made it fast enough even for bluray animations on my rather spiffy machine; your mileage may vary.  If your machine is too slow, you may have to pre-downscale the screengrabs the animations are based on.

Exporting to GIF and MP4 is supported if you have ImageMagick “convert” and “ffpmeg” installed.

I was wondering what a convenient production process for GIFs from movies would be like, so I hacked my hacked version of mplayer a bit more.  Nothing major, since it already has all the functionality, but it doesn’t group continuous screenshots by name, which makes picking out the animations afterwards awkward.

There’s probably a gazillion GIF editors out there already, but since the things you typically want to do with an animation (trim start/end, adjust speed and how many frames to skip) are kinda trivial, it seemed more convenient to just write a mode in Emacs.  So I did.

It uses the ImageMagick “convert” command to actually stitch the images together in the end after you’ve done the edit, so it’s not a pure Emacs-only solution.

And here’s the result:

I’m sure this is going to turn out to be really useful some day!