It's possible using JavaScript. Use the slice() function to do it. More on slice() function at
http://www.w3schools.com/jsref/jsref_slice_string.asp

I suggest using ODBC connection for the Centura database. More on ODBC connection via PHP at
http://www.php.net/manual/en/book.uodbc.php

For web usage and statistics, I suggest awstats (http://awstats.sourceforge.net/), very neat site and shows a lot of information regarding net usage. And best of all, it's open source. Go ahead and...

check where your DOCUMENT_ROOT is located in httpd.conf. I would suggest creating a file called phpinfo.php, and write the following text:
<?php phpinfo(); ?>
into that file. Put this file into...

Try running the image script in a separate page (the image link) and see if there's any error message pops up.
If you don't see any error, configure php.ini to display_error=On and then try again...

Here's the fix:

instead of the normal <% %> thing, switch to <script runat="server"></script>
Now that should solve the problem.