How do I take off my top track sliding doors?
I can't tell from the fuzzy photo whether the hanging hardware has a release mechanism, but typically you'd just swing the door outward (away from the closet) about 20 degrees, so that the top of the wheel clears the upper track lip, then lift it off. Obviously you'd start with the front (outer) slab. 

The post you mentioned shouldn't be an issue. If there's a slide retainer on the floor you'll need to detach it first. 

If those rivets I see engage notches in a two-piece hanger, you may have other options. I suspect that they're permanently attached in this case, though. Some have lever releases.