Hi all,

I try to use rgbdslam for my dataset consisting out of depth and rgb images saved as png.

To make my live easy I tried to write a bag file from these images and then use this bagfile for the rgbdslam. But when I start the reconstruction I get a error about a negative mahalanobis distance and absolut nothing gets reconstructed.

What could be the cause for that? How can even a negative mahalanobis distance emerge?

here is a sample output:

[ERROR] [1359413304.934807938]: Non-Positive Mahalanobis Distance for vectors 2.68921e+22
1.42928e+22
6.56501e+22
1
and
1.08665e-31
7.1891e-32
2.5584e-31
1 with covariances
6.56972e+17           0           0
          0 7.03062e+17           0
          0           0 3.23245e+43
and
2.56023e-36           0           0
          0 2.73984e-36           0
          0           0 4.90904e-64
[ERROR] [1359413304.935060057]: Non-Positive Mahalanobis Distance for vectors -4.749e-39
-3.48146e-39
-1.29024e-38
1
and
7.44725e-30
6.38305e-30
1.98261e-29
1 with covariances
-1.29116e-43            0            0
           0 -1.38174e-43            0
           0            0  1.24853e-78
and
1.98404e-34           0           0
          0 2.12323e-34           0
          0           0 2.94807e-60
[ERROR] [1359413304.935230189]: Non-Positive Mahalanobis Distance for vectors -2.44741e+27
1.18307e+27
4.70933e+27
1
and
-6.61237e-31
3.8003e-31
1.30072e-30
1 with covariances
4.71271e+22           0           0
          0 5.04332e+22           0
          0           0 1.66333e+53
and
1.30165e-35           0           0
          0 1.39297e-35           0
          0           0 1.26891e-62

EDIT 1:

I think the problem lies in the saving and re-conversion to a sensor_msgs of the depth map. My self-written bag file is displayed totally different as the original bag file. I uploaded some Images to explain the problem a little bit better to imgur.com here

There are three screenshots. In every screenshot is the RGBDslam gui plus the window from image_view dispalying the same depth map. When I playback the original reference bag file everything works and the image_view and the RGBDslam display of the depth map are identical. When I playback my own bag file these two are significantly different.