One more thing -- if you have trouble with the scale filter, replace -1 with -2. Nainko's got a much more elaborate solution in forum #104, but it should work fine with -2/%height%.

on Twitter, I often prefer gifs to MP4s because not as much quality is lost during Twitter's processing. Here are their current gif constraints:

  • Resolution should be <= 1280x1080 (width x height)
  • Number of frames <= 350
  • Number of pixels (width * height * num_frames) <= 300 million
  • Filesize <= 15Mb
With my process, duplicate frames are made transparent and large swathes of other frames are made transparent wherever possible. So how small your gif ends up will depend in part on how much is changing from frame to frame.