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How to know if the stereo calibration results are good or not?

Hi Im using two point Grey Chameleon3 mono camera set up as Master Salve and synchronized so can work as stereo camera. I have a installed ROS driver and able to publish the camera topics . Im using this ROS driver https://github.com/KumarRobotics/flea3. And with roslaunch flea3 stereonode.launch left:=18081067 right:=17496474 camera:=stereocamera

can launch the driver.

Then was following the ROS tutorial camera_calibrationTutorialsStereoCalibration to calibrate the cameras. I got 70 samples for the calibration and the epipolar error was around 0.2. This are the Calibration results

 Left:
('D = ', [-0.20826996106865595, 0.18366155924086058, -0.0034661778577718466, 0.00307931151347718, 0.0])
('K = ', [432.82205088588205, 0.0, 272.95231180581044, 0.0, 435.6996693192078, 174.95641222266673, 0.0, 0.0, 1.0])
('R = ', [0.9746296173669449, 0.02700939091034212, -0.22218821245470002, -0.026808041682390916, 0.9996329035169494, 0.003922640364378138, 0.22221259607033478, 0.0021333093834195356, 0.974995903139473])
('P = ', [482.0586696457318, 0.0, 402.53031158447266, 0.0, 0.0, 482.0586696457318, 178.41748809814453, 0.0, 0.0, 0.0, 1.0, 0.0])

Right:
('D = ', [-0.20871659658963718, 0.13988041114304747, -0.0024096479983088267, 0.0031211255518143266, 0.0])
('K = ', [428.59279077571426, 0.0, 275.84270706306677, 0.0, 430.39539990687126, 189.6284029604295, 0.0, 0.0, 1.0])
('R = ', [0.9744460995294874, 0.030491070431326987, -0.22254234144476925, -0.03069272631969819, 0.9995256063000713, 0.002553213962635353, 0.2225146189867814, 0.004342461793354892, 0.9749196825188937])
('P = ', [482.0586696457318, 0.0, 402.53031158447266, -71.0404082822227, 0.0, 482.0586696457318, 178.41748809814453, 0.0, 0.0, 0.0, 1.0, 0.0])
('self.T ', [-0.14360295357921507, -0.004493432498569846, 0.03279579808809728])
('self.R ', [0.999992392164315, -0.003887570979931969, 0.0003200083856870595, 0.0038871258997246238, 0.9999914930203251, 0.0013799055115972527, -0.0003253701440041504, -0.0013786511006187285, 0.9999989967272028])
None
# oST version 5.0 parameters


[image]

width
512

height
384

[narrow_stereo/left]

camera matrix
432.822051 0.000000 272.952312
0.000000 435.699669 174.956412
0.000000 0.000000 1.000000

distortion
-0.208270 0.183662 -0.003466 0.003079 0.000000

rectification
0.974630 0.027009 -0.222188
-0.026808 0.999633 0.003923
0.222213 0.002133 0.974996

projection
482.058670 0.000000 402.530312 0.000000
0.000000 482.058670 178.417488 0.000000
0.000000 0.000000 1.000000 0.000000

# oST version 5.0 parameters


[image]

width
512

height
384

[narrow_stereo/right]

camera matrix
428.592791 0.000000 275.842707
0.000000 430.395400 189.628403
0.000000 0.000000 1.000000

distortion
-0.208717 0.139880 -0.002410 0.003121 0.000000

rectification
0.974446 0.030491 -0.222542
-0.030693 0.999526 0.002553
0.222515 0.004342 0.974920

projection
482.058670 0.000000 402.530312 -71.040408
0.000000 482.058670 178.417488 0.000000
0.000000 0.000000 1.000000 0.000000

I have couple of doubts. First why I have in the Right camera

'self.T ', [-0.14360295357921507, -0.004493432498569846, 0.03279579808809728])
 ('self.R ', [0.999992392164315, -0.003887570979931969, 0.0003200083856870595, 0.0038871258997246238, 0.9999914930203251, 0.0013799055115972527, -0.0003253701440041504, -0.0013786511006187285, 0.9999989967272028])

Then, How to interpret the camera matrix,distortion,rectification and projection matrix and how to know that the numbers are good?

Thanks

Asked by Astronaut on 2018-08-24 03:49:22 UTC

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