Create a d.o compatible mini movie gif rather than a static screenshot

creategif

#!/bin/sh

# Create an animated GIF of a screen recording to upload to d.o
# Usage: creategif input_file.mp4 output_file.gif
# As described at http://blog.pkh.me/p/21-high-quality-gif-with-ffmpeg.html

palette="/tmp/palette.png"

filters="fps=15,scale=1280:-1:flags=lanczos"

# GIF supports a 256 colour palette. Determine the best palette and store as temp file
ffmpeg -v warning -i $1 -vf "$filters,palettegen" -y $palette

# Use the stored palette to encode the GIF
ffmpeg -v warning -i $1 -i $palette -lavfi "$filters [x]; [x][1:v] paletteuse" -y $2

You'll need to install ffmpeg (Mac: brew install ffmpeg) and have this script somewhere handy.

Use the QuickTime app on your Mac to record a screen recording and then save as a file somewhere - mp4 format is good.

Put this script in /usr/local/bin and run it on the file which will give you a gif file to upload to d.o BUT CHECK HOW BIG IT IS before uploading!!