make mac os app icons (need 50 pixels padding around, see https://bootcamp.uxdesign.cc/creating-app-icons-for-macos-11-and-up-1132ccd479bc )

make-macapp-icon-ffmpeg.sh

if [ "$#" -eq 2 ]
then
mkdir $2

ffmpeg -y -i $1 -vf scale=16x16 $2/icon-16x16@1x.png
ffmpeg -y -i $1 -vf scale=32x32 $2/icon-16x16@2x.png
ffmpeg -y -i $1 -vf scale=32x32 $2/icon-32x32@1x.png
ffmpeg -y -i $1 -vf scale=64x64 $2/icon-32x32@2x.png

ffmpeg -y -i $1 -vf scale=128x128 $2/icon-128x128@1x.png
ffmpeg -y -i $1 -vf scale=256x256 $2/icon-128x128@2x.png

ffmpeg -y -i $1 -vf scale=256x256 $2/icon-256x256@1x.png
ffmpeg -y -i $1 -vf scale=512x512 $2/icon-256x256@2x.png

ffmpeg -y -i $1 -vf scale=512x512 $2/icon-512x512@1x.png
ffmpeg -y -i $1 -vf scale=1024x1024 $2/icon-512x512@2x.png

else
    echo "please pass your image filename and a directory to put results in"
    exit 1
fi