Re: [docbook-apps] Mediaobjectco, callouts

[Michael Smith <smith@xml-doc.org>]

"Thomas, Ludger" <Ludger.Thomas@iese.fraunhofer.de> writes:

> Dear all,
> I wonder if there is a solution to handle screenshots and callouts. As
> "Unfortunately, this feature is currently not implemented in the DocBook
> XSL stylesheets."
> (http://www.sagehill.net/docbookxsl/AnnotateListing.html)

As far as PDF output, it is implemented in dblatex -

  http://dblatex.sourceforge.net/

> we currently have to do this by hand, which is not really
> satisfactory and efficient.
> Are any approaches available we could use to handle screenhots more
> efficiently and automate the update of screenshots and embedded callouts
> (e.g. extension for Saxon ...)?

For HTML output, I guess the extension would need to create a
composite image: the original image composited with an overlay
with the callouts in the right places.

The ImageMagick library does compositing (see the composite(1)
docs). There is a Java interface to that. Also C++, Perl, Python,
Ruby, and Tcl interfaces. 

I imagine it is technically possible to write an extension that
would use that. It would need to get the dimensions of the
original image, then create another image of the same dimensions,
but just with the callouts in it, then composite them together.

  --Mike

-- 
Michael Smith
http://sideshowbarker.net/