Camera self-calibration

Camera calibration is the recovery of intrinsic parameters of camera. The standard off-line calibration procedure is to acquire images of an object with known Euclidean structure and compute the camera matrix that minimizes the error between the image of the object and its reprojection.

Self-calibration methods can be used when no Euclidean information is available , and, if properly designed, can also cope with varying intrinsic parameters. If the intrinsic parameters are wrong, the reconstruction will suffer from a projective distortion even if the motion is correct.

Reference จาก http://mi.eng.cam.ac.uk/~prdsm2/Research/SelfCalibration/

Type of camera parameters

1. Extrinsic camera parameters : the parameters that define the location and orientation
   of the camera reference frame with respect to a known world reference frame.
   These are the parameters that identify uniquely the transformation between the
   unknown camera reference frame and the known world reference frame
   
2. Intrinsic camera parameters: the parameters necessary to link the pixel coordinates of
   an image point with the corresponding coordinates in the camera reference frame.
   

Reference : http://www.cse.unr.edu/~bebis/CS791E/Notes/CameraParameters.pdf