I tested the rtabmap on kitti datasets with different sequences. I find that the results are not good. To be specific, the dense cloudpoints map has many empty areas, especially road surface. The following picture is the result of sequence 2011_09_26_drive_0001_sync. Note that there is almost no road surface but just some lane lines. I wonder why the results for kitti are not good? Maybe the influence of illumination? or other reasons? Is there any methods to improve it?
The disparity image is generated by cv::StereoBM by default. Normally when there is not a lot of texture, the algorithm won't compute any disparity. cv::StereoSGBM can be also used, but at a higher cost. Look at the corresponding parameters: