The ground truth files must be created manually. You can use Gimp/MsPaint to create a matrix of the ground truth. Black pixels are no loop closures and white pixels are loop closures.
To help creating the ground truth, you can use the rtabmap-console to generate a first draft "ground truth" using the "-createGT" argument. You should manually verify that white pixels are correct and add a margin around the loop closures detected. You may need to add white pixels on loop closures not found.
For example with the
sample dataset:
$ cd rtabmap/bin
$ ./rtabmap-console -createGT data/samples
The generated ground truth "GroundTruth_generated.bmp" can be compared to the manually updated one
here. I put them here for info:
---- manually update --->
(Note also that I have just fixed an
issue for the saved file name.)
After that, you can follow directives on the
Benchmark page to compute Recall/Precision curve using the ground truth created.