3d Tracking Issues in PFHoe and PFTrack

What seemed to be a rather simple shot turned out to be much more difficult than originally anticipated. I originally shot this for a PFhoe Tutorial on 3d tracking. (http://www.pfhoe.com/) This is Pixel Farms entry level 3d tracking program. I ran the shot through that, and got an o.k. track, but far from perfect. There was a lot of slipping of the 3d elements, and I was having a tough time orienting the table top in 3d space. Since the analyzing tools in PFHoe are just about non-existent, I brought it into the big boy, PFTrack to see how that handled it. First it went through the automatic tracking, and what I got was a complete mess. When I looked at the results, what finally dawned on me was that the scene has a bunch of high contrast areas that the program is picking up as tracking points, but that are not true spots in 3d space. Only after basically throwing out about 90% of the automatic tracks, and adding 30 manual tracks of my own, was I able to get a decent result. It is still not perfect, as there are some pixel slips, but I am working on it. Click the picture for a larger view of some areas I point out that were false positives coming from the automatic tracker. The underside of the table is very high contrast to the floor, causing intersections that look like good spots to track to the program, but indeed do not stay in the same point in 3d space throughout the shot, therefore giving erroneous tracks. Needless to say, this does not make a good shot for a PFhoe tutorial. Guess I should maybe do a PFTrack tutorial instead.

PF Track Dining Room Table Test from Art Guglielmo on Vimeo.