Where is the Focal length, principle point and radial distortion coefficients

[zhang.wei...@gmail.com]

Now I run the calibration toolbox successfully. But I am not clear on the output parameters.

So I want to know how can I get such parameters, including focal length, principle point and radial distortion coefficients like the output of "http://www.vision.caltech.edu/bouguetj/calib_doc/".

Thanks very much!

Best regards!

Weichen

[Straw,Andrew]

On 15 Jun 2013, at 6:01 AM, zhang.wei...@gmail.com wrote:

Now I run the calibration toolbox successfully. But I am not clear on the output parameters.

So I want to know how can I get such parameters, including focal length, principle point and radial distortion coefficients like the output of "http://www.vision.caltech.edu/bouguetj/calib_doc/".

You can decompose the P matrix given in the *.Pmat.cal files. I haven't followed it in detail, but the following blog post looks like a good treatment of how to do this decomposition from a practical perspective: http://ksimek.github.io/2012/08/14/decompose/

I have Python code online in my camera_model package, which is a pure-Python implementation of ROS/OpenCV compatible cameras. Around line 865 is the RQ decomposition in which the P matrix is decomposed into intrinsic parameters that you request. https://github.com/strawlab/camera_model/blob/master/src/camera_model/camera_model.py#L865

Best,

Andrew