Hi Marion,
We haven't implemented specifically this feature, but we have done something similar that perhaps you could adapt for your needs.
As of v4.5, NCrunch is now able to export code coverage data in partcover format. You can export this using the export button on the Tests Window toolbar, and it is also automatically exported by the NCrunch console tool.
The partcover file contains the coverage data in IL sequence point form, so it's aligned with the basic method/class structure. I would hope it should be relatively simple to write a tool that can read from this file and translate it to whatever format you need.