Function estimateWo​rldCameraP​ose() or extrinsics() for fisheyeParameters is missing. Is it possible to change these functions for fisheye?

I am using a camera system which has a fisheye lens. I have calibrated the camera and I have the intrinsics. I want to estimate the extrinsics and camerapose for the camera. I have imagePoints, worldPoints and parameters of the camera.

But the function - estimateWorldCameraPose() cannot accept fisheyeParamaters or fisheyeIntrinsics.

My error is -

Error using estimateWorldCameraPose

Expected cameraParams to be one of these types:

cameraParameters, cameraIntrinsics

Instead its type was fisheyeIntrinsics.

Is it possible to change these functions for fisheye?

Or is it mathematically not possible?

Thank you.

Answer 1

[Qu Cao]

fisheyeIntrinsics can't be used directly. Instead, you can use undistortFisheyeImage function to produce both undistorted image for further processing and a "virtual perspective" camera intrinsics. See syntax which returns "camIntrinsics"

The new camIntrinsics can then be used in workflows involving a pinhole camera. It is a virtual pinhole camera created from the original fisheye camera. This new intrinsics object (non-fisheye) can then be fed into estimateWorldCameraPose.

[POORNAPRAGNA LS]

Thank you for the response.

Would the camera pose from estimateWorldCameraPose would be the camera pose of the virtual pinhole camera and not the actual camera? Or would both be the same?

[Qu Cao]

Both would be the same.

[POORNAPRAGNA LS]

Thank you. A link to a documentation about this to read up would be great.

[POORNAPRAGNA LS]

As a follow up to this question, would the focal length and principal point of the virtual camera extracted from undistortFisheyeImage be the same as the focal length and principal point of the actual camera?

[Ron Leonard]

the focal length and principal point return by undistortFisheyeImage isn't same with the actual camera. the new parameters is the virtual and ideal pinhole camera's.