Re: Database Post Processing - Save refined links

Posted by matlabbe on
URL: http://official-rtab-map-forum.206.s1.nabble.com/Database-Post-Processing-Save-refined-links-tp6504p6520.html

Hi Davide,

It seems to be a g2o issue. If I set Optimizer/Strategy=2 (GTSAM) instead, the modified graph is exactly the same when re-opening the database. I think g2o fails because it is a little more sensible to covariances in the links. When we refine, we change those covariances. But why it doesn't re-optimize exactly the same on reload is still an open question... we would have to debug if the poses+covariances that we feed to optimizer are the same just after refining and when we reload the database.

Note that in the database, Reg/Strategy=0, set to 1 if you want to refine with lidar. PM/OutlierRatio=0.01 is very low, normally it would be between 0.5 and 0.9 (the lower the more robust to dynamic objects). In general outdoor, I would not set Reg/Force3DoF to true because the terrain is rarely perfectly flat.

cheers,
Mathieu