Idea/Mechanism how to include images from variable locations dynamically

[Stefan Zander <szander@multamedio.de>]

Hello everybody,

maybe somebody has a good hint / idea for solving my problem:

I need to find a way how to include images form a specific directory 
into a docbook xml file, where the path from which the images are taken 
should by specified dynamically at the beginning of the generation 
process. The directory path from which the images are taken is variable 
and depends on the case/user the document is intended to.

To put it into simpler words: I need a mechanism to tell e.g. the 
processor or a stylesheet at the beginning of the processing which 
location should be used.

I am thinking of using a parameter whose value determines which 
directory is used to include the images.

The images are included in separate files (referring to book chapters or 
sometimes to sections - for modularity reasons) which are then included 
in the main-document using the <xi:include href.../> element. The 
separate xml-files contain the content of chapters/sections whereas the 
main-document specifies the structure and sequence of the final document.

The code for including the images in each separate xml-file looks like this:
...
<figure>
  <title>title of figure</title>
  <mediaobject xml:base="...">
    <imageobject >
      <imagedata fileref="{directory}/{filename}.png" width="100%" 
scalefit="1" format="PNG" align="center" />
    </imageobject>
  </mediaobject>
</figure>
...
{directory} should be replaced by the location specified e.g. by a 
parameter whereas {filename} is a fixed entry (the filename an image).

The clue behind is to use a specific/individual set of images for each 
user the document is intended to.

I tried to use xml catalogs but it seems not to work.

I am working with:
- Windows XP SP 1
- Java 1.5
- xmllint for win32
- fop-0.92beta
- docbook DTD 4.4
- docbook-stylesheets 1.70.1

I hope I described it clear enough. If not I would be very thankful to 
provide you further information.

Best Regards

Stefan