Now converting Gifs to MP4s w/mmpeg & imagemagick

After ironing out a couple of access issues, the current situation is
that when a user adds a gif the gif is downloaded to the server, which
then uses ImageMagick to slice the frames of the gif into individual
.png files.

Ostensibly I should then be using ffmpeg to compile the indi frames into
an MP4, but at the moment I"m literally just converting the gif into an
mp4 with ffmpeg.

However, there are some framerate issues, and the guys at Gfycat shared
the following process:

"...we first use ffmpeg to extract all frames to pngs. Then we run
imagemagick "identify" to dump all of the centisecond delays into an
array. Then we run through the array and duplicate or cut frames as
required to best fit the gif timing. Finally, we run ffmpeg to generate
the h.264 and webm files. We chose not to override ffmpeg with set
bitrates, but use constant rate factor to let it do the optimizing"

So, at the moment it looks as though I'm missing the middle step of
adding the frames to an array and doing a check & dump before sending to
mmpeg.

Nonetheless, very pleased with the progress in 2 night's work.  Once the
conversion step is all sorted, the last part is to work on a script that
will swap out the .gif url for the mp4 / webm urls, and also use the
<video> tag in html5 in order to provide fallback depending on the
browser environment.

Nice.