Fig. 3From: Camera calibration with coplanar conics: a unified explanation and ambiguity analysisFour conics classes with different shapes. From left to right, they are respectively PAP conics with three DOF, OPAS conics with two DOF, concentric conics with two DOF, and PAA conics with one DOF. Their quadrangles are respectively a quadrangle whose four vertices lie on a common circle, a trapezoid, a parallelogram, and a rectangleBack to article page