#!/bin/sh

font=/usr/X11R6/share/fonts/microsoft/arialb.ttf

for colour in white black; do
   for chr in A B C D E F G H I J K L M N O P Q R S T U V W X Y Z \
              0 1 2 3 4 5 6 7 8 9; do
     convert -size 100x100 xc:black -transparent black -font $font \
             +antialias -pointsize 40 -fill $colour -draw "text 0,100 '$chr'" \
             -crop 0x0 \
             x.png
     pngcrush -allb x.png font/$chr-$colour.png
     rm x.png
   done
done