Malte, Dave:
I haven't seen how the image procedures work here. I wrote a module for AOLserver which allows upload of a gzip file of original images and extracts them. Then creates a series of smaller versions of each image. You can specify the sizes and a number of other options.
Most of it is not useful outside of the package, but I noticed a single procedure which takes some options for convert and creates a conversion string. There are a lot of options and you can't just plug them in, they have to be calculated. It also detects the orientation of the image.
The proc is ::qphoto::photo::convertOptions and is available in this page, near the bottom:
http://rmadilo.com/m2/servers/rmadilo/modules/tcl/twt/packages/quick-photo/tcl/quick-photo-procs.tcl
When working on this I tried Imagemagick loaded into Tcl. It was a shared library and didn't require exec. However I fould it to be significantly slower at conversions than simply exec'ing convert.
An example of the data used as input is in:
http://rmadilo.com/albums/tom/IHD2005/series.rdl
The output data is in:
http://rmadilo.com/albums/tom/IHD2005/photo.rdl
There is a form for testing out the conversion proc here:
http://rmadilo.com/albums/tom/coptions-form
