maplab
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Published
20 hours ago •
ethz-asl
ethz-asl
External features
Work in progress PR, don't review yet.
Usage
Commands such as elq and rtl remain the same and are agnostic to the feature type. They will just individually process all features of all types. Commands that have extra flags now are:
v:
- You can visualize all features side by side colored by feature type using
--vis_color_by_landmark_type=true, for this I also it helps to choose a new salt since the default one gives you a bad color pattern--vis_color_salt=1337. - You can visualize only one feature type at a time with
--vis_show_only_landmark_typeand then the name of the feature (at the moment eitherBinaryorR2D2).
optvi:
- By default, all features will be optimized with equal weighting. If you want to optimize only one feature type use
--ba_visual_feature_typeand the name of the feature. No multiselection is yet available.
lc:
- Default behavior is to loop-close the binary features with the standard parameters. To select another feature type use
--lc_feature_typeand the feature name. For floating point based features select the flann search engine with--lc_detector_engine=flann. - I found it beneficial to increase the number of neighbors to search for to for example
--lc_num_neighbors=16, but be warned this increases quite exponentially the amount of time you need to spend on RANSAC then and you should increase the number of iterations--lc_num_ransac_itersto for example at least10000for16neighbors. - With SuperPoint features I found the minimum inlier ratio
--lc_min_inlier_rationeeded is much smaller0.05 - 0.1(default is0.2) but then to compensate you can drastically increase the minimum inlier count--lc_min_inlier_countto like40 - 100(default is10). - Some tuning of the sigma can also help
--lc_ransac_pixel_sigma. With the default of1.0it finds still a lot of loop closures and remains relatively conservative. With a higher sigma of2.0, I still didn't notice erroneous loop closures but there were definitely a lot more difficult perspectives that loop closed. - Using
-v=6helps show a lot of the output and is useful in tuning both the duration and the different inlier ratio / count. Maybe a bit too verbose as a default.
aam:
- Has the same parameters as
lcand you can copy what worked there, BUT there are two extra checks that need to pass which aremap_anchoring_min_medial_inlier_ratioandmap_anchoring_min_num_vertex_links. For the sake of simplicity and no headaches it makes sense to setmap_anchoring_min_medial_inlier_ratioto the same min inlier ratio as inlc. (We might want to consider removing this parameter since it seems more trouble than it's worth)
