iOS icon resizer script

Goodness, iOS 6 & 7 needs a lot of different icon sizes for a universal app. I wish Apple would support SVG. Here's my little script to resize a large icon down. It requires Imagemagick.

#!/bin/bash
# Usage: iconmaker.sh bigicon.png
# You need to brew install imagemagick
filename=$(basename "$1")
extension="${filename##*.}"
filename="${filename%.*}"
echo "resizing ${filename}..."
echo "filename = $filename"
for size in 29 40 50 57 58 72 76 80 100 114 120 144 152
do
    echo "$filename$size.png"
    convert {$1} -resize $sizex$size $filename$size.png
done

This is a note to myself really.