Make a multi-resolution favicon.ico from a source image, using ImageMagick

mkfavicon.sh

#!/bin/bash

# from
# http://bergamini.org/computers/creating-favicon.ico-icon-files-with-imagemagick-convert.html

convert source-WxW.png -resize 256x256 -transparent white favicon-256.png
convert favicon-256.png -resize 16x16 favicon-16.png
convert favicon-256.png -resize 32x32 favicon-32.png
convert favicon-256.png -resize 64x64 favicon-64.png
convert favicon-256.png -resize 128x128 favicon-128.png
convert favicon-16.png favicon-32.png favicon-64.png favicon-128.png favicon-256.png -colors 256 favicon.ico