I like to design using Omnigraffle, which can save files in PDF and several other standardized vector formats. I realize that "mockup to HTML" paid crowdsourcing services are a dime a dozen, but what about automatic conversion? Of course it's a very hard problem to solve computationally, but...
What are the most reliable software tools out there for automatically (or semi-automatically) converting a mockup (i.e. a PDF showing rectangular regions of color, text, and graphics) into tidy HTML+assets?
This is not asking about anything interactive like FORM controls, just static visual layout expressed cleanly in HTML.