The most commonly used camera calibration method is perhaps the DLT (direct linear
transformation) method originally reported by Abdel-Aziz and Karara [1]. The DLT method uses a
set of control points whose object space/plane coordinates are already known. The control points
are normally fixed to a rigid frame, known as the calibration frame. The problem is essentially to
calculate the mapping between the 2D image space coordinates (xi
) and the 3D object space
coordinates (Xi
). For this 3D ÅÆ 2D correspondence the mapping should take the form of a 3x4
projection matrix (P) such that xi
= PXi
for all