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### visp_auto_tracker does not output pose data and unable to track properly

Hi all,

visp_auto_tracker was working perfectly fine for me until today...when I ran visp_auto_tracker, I got the message below repeatedly as the webcam tracked the QR code.

 *********** Parsing XML for Mb Edge Tracker ************
ecm : mask : size : 5
ecm : range : tracking : 10
ecm : contrast : threshold 5000
ecm : contrast : mu1 0.5
ecm : contrast : mu2 0.5
sample : sample_step : 4
sample : n_total_sample : 250
klt : Mask Border : 0
klt : Max Features : 10000
klt : Windows Size : 5
klt : Quality : 0.01
klt : Min Distance : 20
klt : Harris Parameter : 0.01
klt : Block Size : 3
klt : Pyramid Levels : 3
face : Angle Appear : 75
face : Angle Disappear : 75
camera : u0 : 325.03 (default)
camera : v0 : 219.983 (default)
camera : px : 523.553 (default)
camera : py : 520.561 (default)
(L0) !! /tmp/buildd/ros-hydro-visp-2.9.0-4precise-20140617-1429/src/camera/vpCameraParameters.cpp: get_K(#403) :
getting K matrix in the case of projection           with distortion has no sense
Tracking failed

getting K matrix in the case of projection                   with distortion has no sense
Tracking done in 33.239 ms


When I check "rostopic echo /visp_auto_tracker/object_position", I saw that I was no longer getting any pose data from the webcam. The tracking markers that were supposed to show up on the debug display window were no longer there as well. I noticed there were only 8 markers at the corners of the QR code labelled: mi1, mi2, mi3, mi4, mo1, mo2, mo3, mo4. I'm kind of stumped since this problem came out of nowhere and I don't recall changing anything either. Any help is greatly appreciated. Thanks!