Generate a GIF header for your Misskey profile

misskey-gif-header.sh

#!/bin/sh
# License:  AGPLv3
# Author:   Tassoman
# URL:      https://github.com/tassoman

if [ "$#" -ne 2 ]; then
    echo "Usage: $0 <input_video> <output_gif>"
    exit 1
fi

if [ "${2##*.}" != "gif" ]; then
    echo "Error: The output file must have a .gif extension."
    exit 1
fi

palette="/tmp/palette.png"
file="${2%.*}"

ffmpeg -v error -i "$1" -vf "fps=15,scale=640:-1,palettegen" -y "$palette"
ffmpeg -v error -i "$1" -i "$palette" -lavfi "fps=15,scale=640:-1[p];[p][1:v]paletteuse=dither=bayer:bayer_scale=3" -fs 256K -y "$2"
file $2