makegif.sh

#!/bin/sh

# From http://blog.pkh.me/p/21-high-quality-gif-with-ffmpeg.html

# Usage:
# ./makegif.sh export01 output.gif

palette="/tmp/palette.png"

filters="scale=640:-1:flags=lanczos"

frames=`mktemp -d`

for i in 1; do
    for file in $1/*.png; do
        filename=$(basename "$file")
        cp $file "$frames/$i-$filename"
    done
done

ffmpeg -thread_queue_size 512 -v warning -pattern_type glob -i "$frames/*.png" -vf "$filters,palettegen=stats_mode=diff:max_colors=16" -y $palette
ffmpeg -thread_queue_size 512 -v warning -pattern_type glob -i "$frames/*.png" -i $palette -lavfi "$filters [x]; [x][1:v] paletteuse=dither=sierra2_4a" -y $2

rm -r $frames