mov-to-gif.sh

#!/usr/bin/env bash
#
# Convert a .mov or .mp4 to a .gif using ffmpeg and gifsicle.
#
# Tools install: https://gist.github.com/dergachev/4627207#installation
#
# Sources:
# 1. https://discovergrid.com/animated-gif-with-ffmpeg-palettegen/
#    Use ffmpeg with a generated palette to map colors better
# 2. https://gist.github.com/dergachev/4627207
#    Gifsicle usage
# 3. https://www.robinstewart.com/blog/2018/10/adding-a-delay-to-the-end-of-an-animated-gif/
#    Add a delay at the end of the movie

# usage: $0 [-f FPS] .mov files...
getopts 'f:' fps
if [ "$fps" -a "$fps" != '?' ]; then
    fps=$OPTARG
else
    fps=10
fi

while [ $OPTIND -gt 1 ]; do
    shift
    OPTIND=$[ $OPTIND - 1 ]
done

while [ "$1" ]; do
    f=$1
    p=${f/.mov/}.palette.png
    g=${f/.mov/.gif}
    ffmpeg -y -i $f -vf fps=$fps,palettegen $p
    ffmpeg -y -i $f -i $p -filter_complex "fps=$fps[x];[x][1:v]paletteuse" -f gif - \
        | gifsicle -d3 "#0--2" -d200 "#-1" -O2 > $g
    rm $p
    shift
done