Typography in 8 bits: System fonts (2011)(damieng.com)

  $ convert charset.png -crop 256x48+0+0 +repage c6847.png
  $ convert c6847.png -crop 8x12 +repage +adjoin 'c6847g%02x.png'

  $ convert c6847.png -threshold '1%' c6847.gif
  $ for p in c6847g??.png; do convert "$p" -threshold '1%' "`basename $p .png`".gif; done

  $ curl -O http://czyborra.com/unifont/gif2bdf

  @@ -5,20 +5,19 @@
   # into a handier bitmap distribution format font
   
   $[ = 1; $chars=$#ARGV; undef $/; 
  -
  +$dec = 32;
   for (@ARGV)
   {
  -     $dec = hex ($hex) if ($hex) = /([0-9A-F]{4})/ || next;
  +     $hex = sprintf("%04x", $dec);
        $_ = `giftopnm $_`;
        s/^P4\s(\d+)\s(\d+)\s/$wid=$1,$nib=$wid>>2,$ht=$2,''/e;
        $_ = unpack ("H*", $_);
        s/(.{$nib})/\n$1/g;
        $header ||= print "STARTFONT 2.1
  -FONT -Unicode-Charts-Medium-R-Normal--$ht-${ht}0-72-72-C-${wid}0-ISO10646-1
  +FONT -c6847-fixed-medium-r-normal--$ht-${ht}0-72-72-C-${wid}0-iso8859-1
   SIZE $ht 72 72
   FONTBOUNDINGBOX $wid $ht 0 0
  -STARTPROPERTIES 4
  -COPYRIGHT http://www.unicode.org/unicode/copyright.html
  +STARTPROPERTIES 3
   DEFAULT_CHAR -1
   FONT_ASCENT $ht
   FONT_DESCENT 0
  @@ -33,7 +32,10 @@
   BITMAP$_
   ENDCHAR
   ";
  -
  +     $dec = $dec + 1;
  +     if ($dec == 96) {
  +             $dec = 192;
  +     }
   }
   
   print "ENDFONT\n";

  $ ./gif2bdf `ls c6847g??.gif | sort` > c6847.bdf
  $ bdftopcf c6847.bdf > c6847.pcf