Use of very wide angle fisheye cameras

[visocopter]

Hi,

is it possible to use a fisheye camera with a very high FOV (>180 deg) fisheye lens with Open Vins?

I have a global shutter camera and would like to use a circular 180 degree fisheye lens.
As I understood the documentation, there are two camera models supported: pinhole-equi and pinhole-radtan.

Would the pinhole-equi model sufficient for this task?
Or generally: What would have to be done to use a circular 180 degree fisheye camera?

Keep up the great work!

Cheers,
James

[goldbattle]

We leverage the opencv fisheye mode:
https://docs.opencv.org/master/db/d58/group__calib3d__fisheye.html

My understanding that their model does not support very large FOV cameras. Additionally, I think some of the estimation code for triangulating features would need to be changed as right now we assert that features must lie in front of the camera, thus for >180deg this won't hold since features can lie behind the camera frame. I don't have any experience with these cameras, but I think another issue is performing feature tracking on these large FOV angles due to the large amounts of distortion. You can try selecting a region of interest in the middle of the image to reduce the FOV is you are stuck with a high FOV sensor.

[visocopter]

Alright thank you very much.
Would a 160 degree lens work then with the existing models since the image wouldn't be behind the frame?
(Like the Intel Realsense T265, which has a 160 degree FOV I think)

[goldbattle]

Yes, you can checkout the other issues created for that.

• Camera frame moves crazy in RVIZ with D435i #64 (comment)
• T265 calibration using Kalibr #97
• https://github.com/rpng/open_vins/issues?q=T265+

[visocopter]

Okay thank you!