Generate an iconset and .icns for a given image

iconset.sh

# $1 = the path to your png image
imageDir=$(dirname $1);
filename=$(basename $1);
name="${filename%.*}";

# create iconset directory
iconsetDir="${imageDir}/${name}.iconset";
mkdir $iconsetDir;

# generate resized images
sips -z 16 16     $1 --out "$iconsetDir/icon_16x16.png";
sips -z 32 32     $1 --out "$iconsetDir/[email protected]";
sips -z 32 32     $1 --out "$iconsetDir/icon_32x32.png";
sips -z 64 64     $1 --out "$iconsetDir/[email protected]";
sips -z 128 128   $1 --out "$iconsetDir/icon_128x128.png";
sips -z 256 256   $1 --out "$iconsetDir/[email protected]";
sips -z 256 256   $1 --out "$iconsetDir/icon_256x256.png";
sips -z 512 512   $1 --out "$iconsetDir/[email protected]";
sips -z 512 512   $1 --out "$iconsetDir/icon_512x512.png";
sips -z 1024 1024 $1 --out "$iconsetDir/[email protected]";

# create an .icns file
iconutil -c icns $iconsetDir;