A large number (170/172) of stereo correspondences are rejected! Optical flow may have failed because images are not calibrated, the background is too far (no disparity between the images), maximum disparity may be too small (128.000000) or that exposure between left and right images is too different.

[Dzksaigao]

Hi! I'm using a stereo camera to map in gazebo.
I tried
/Stereo/OpticalFlow to false
and
Vis/CorFlowMaxLevel to 5
Stereo/MaxDisparity to 200
but it still warns

[matlabbe]

Could be bad stereo images. Can you show an example of left and right images that you feed to rtabmap? That warning would appear with/without optical flow stereo approach.