Re-phrase

[Sam Post <sampost gmail com>]

I haven't heard from anybody, so maybe I'll rephrase my question in
case it wasn't clear the first time.

How do you convert the following SVG code:

<svg width="22cm" height="7cm" viewBox="2 -4 22 7">
  <polygon style="fill: #ffffff" points="3.05,-3.8695 5.45,-3.8695
6.05,-3.2695 6.05,-2.1695 3.05,-2.1695 "/>
  <text style="fill: #000000; text-anchor:start; font-size: 0.8;
font-family: monospace; font-style: normal; font-weight: normal"
x="3.4" y="-2.6695">John Q</text>
...
</svg>

to an image map: 

<map name="mymap">
<area SHAPE=RECT COORDS="X,Y X2,Y2">
<area SHAPE=RECT COORDS="X,Y X2,Y2">
</map>

Any ideas? I'd like to be able to use Dia to make an image, then run a
simple script that reads the dia/svg file and outputs html for a
clickable image map. The problem is, dia's coordinate system is in
centimeters and I can't figure out how to get this into pixels, which
is what jpg's and png's use.

Thanks in advance,

Sam