Unexpected OCam model polynomial coefficients

Please provide the following info (check/uncheck the boxes after clicking “+ Create Topic”):
Software Version
DRIVE OS Linux 5.2.0
DRIVE OS Linux 5.2.0 and DriveWorks 3.5
[/] NVIDIA DRIVE™ Software 10.0 (Linux)
NVIDIA DRIVE™ Software 9.0 (Linux)
other DRIVE OS version

Target Operating System
[/] Linux

Hardware Platform
[/] NVIDIA DRIVE™ AGX Xavier DevKit (E3550)
NVIDIA DRIVE™ AGX Pegasus DevKit (E3550)

SDK Manager Version

Host Machine Version
[/] native Ubuntu 18.04

I am calibrating a camera using the calibration-intrinsics-constraints tool.
The calibration seems to be ok, and the video rectified with sample_video_rectifier looks correct.

however, the forward and inverse polynomials of the model are strange:

forward: [676.1050714975685, -0.01169171556569286, -0.0005566429701918019, 1.2019803248201785e-07, -3.5811988209938536e-10]
inverse: [936.2182648407941, -495.4591675435748, 89.17092463783173, -528.9162828835699, 999.4693482079628, -1229.616616003521, 904.7211263402859, -351.71115269928714, 55.43655195011205]

according to

Davide Scaramuzza, Agostino Martinelli, Roland Siegwart. A Toolbox for Easily Calibrating Omnidirectional Cameras. Iros, 2006, Benjing, China. ffinria-00359941f

coefficient a1 of the forward polynomial is supposed to be equal to 0

also, the plot of the inverse polynomial is unexpected.
A correct inverse polynomial should look like this:

while the inverse polynomial looks created by tool like this:

at -pi/2 indeed the inverse polynomial should be close to 0 (projection at the center of the image)

Is the nvidia SDK using a different formula than the one described in Scaramuzza’s paper?

Hi @VComito ,

We will check internally and get back to you. Thanks.

We would suggest you to not use OCAM, as we’re probably gonna deprecate it. Please use FTheta instead.