Unfortunately, we do not have .pdf parsing/renderning at this time in the library.
That said, I was faced with the same problem some time ago. I have solved it by using "pdftoppm.exe" commandline utility, run as 'slave' program, then interpreting results. I am not sure what counds as "launch external program" in your environment, but I would say that launching commandline should be possible for you.
I can send you some snippets of code if you like this path.