CameraCalibration Methods 
The CameraCalibration type exposes the following members.
Name  Description  

CalibrateCamera 
Estimates intrinsic camera parameters and extrinsic parameters for each of the views
 
EstimateRigidTransform 
Estimate rigid transformation between 2 point sets.
 
GetAffineTransform 
Calculates the matrix of an affine transform such that:
(x'_i,y'_i)^T=map_matrix (x_i,y_i,1)^T
where dst(i)=(x'_i,y'_i), src(i)=(x_i,y_i), i=0..2.
 
ProjectPoints 
Computes projections of 3D points to the image plane given intrinsic and extrinsic camera parameters.
Optionally, the function computes jacobians  matrices of partial derivatives of image points as functions of all the input parameters w.r.t. the particular parameters, intrinsic and/or extrinsic.
The jacobians are used during the global optimization in cvCalibrateCamera2 and cvFindExtrinsicCameraParams2.
The function itself is also used to compute backprojection error for with current intrinsic and extrinsic parameters.
 
SolvePnP 
Estimates extrinsic camera parameters using known intrinsic parameters and extrinsic parameters for each view. The coordinates of 3D object points and their correspondent 2D projections must be specified. This function also minimizes backprojection error.
 
StereoCalibrate 
Estimates transformation between the 2 cameras making a stereo pair. If we have a stereo camera, where the relative position and orientatation of the 2 cameras is fixed, and if we computed poses of an object relative to the fist camera and to the second camera, (R1, T1) and (R2, T2), respectively (that can be done with cvFindExtrinsicCameraParams2), obviously, those poses will relate to each other, i.e. given (R1, T1) it should be possible to compute (R2, T2)  we only need to know the position and orientation of the 2nd camera relative to the 1st camera. That's what the described function does. It computes (R, T) such that:
R2=R*R1,
T2=R*T1 + T
