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Hi!

I'm porting to opencv a little script for lens distortion correction.

This program is doing the undistortion with the Brown normalization, and it uses some parameters that gets out of a (close source) software for camera calibration that has values in the so called photogrammetric representation.

The main difference I have noticed till now is that it express values of focal length and principal points in mm while opencv undistort function takes values in pixel. Ok, I have pixel dimension and I can do this conversion.

But.. Even after this conversion the cv::undistort function still gets me an image that is not correctly undistorted.

I think that there should be some scaling factor that I'm not considering. So I'm asking: what are the values of distortion coefficent units? Are they in radians? Or there is some other conversion that I have to do? Some advice?

Hi!

I'm porting to opencv a little script for lens distortion correction.

This program is doing the undistortion with the Brown normalization, and it uses some parameters that gets out of a (close source) software for camera calibration that has values in the so called photogrammetric representation.

The main difference I have noticed till now is that it express values of focal length and principal points in mm while opencv undistort function takes values in pixel. Ok, I have pixel dimension and I can do this conversion.

But.. Even after this conversion the cv::undistort function still gets me an image that is not correctly undistorted.

I think that there should be some scaling factor that I'm not considering. So I'm asking: what are the values of distortion coefficent units? Are they in radians? Or there is some other conversion that I have to do? Some advice?