An apparatus for calibrating a stereoscopic camera (401, 402, 501, 502), the apparatus comprising: - a processing unit configured to support at least a first triangulation unit, a second triangulation unit and a Bundle Adjustment unit, with respect to at least one stereo-image of the stereoscopic camera, wherein: - the first triangulation unit and second triangulation unit are coupled to the Bundle Adjustment unit; - the first triangulation unit is configured to generate a first plurality of 3D object-point coordinates estimates, E3D, based on at least a plurality of measured 2D image-point correspondences, PCO, of the stereo-image and an initial calibration estimate, CAE, of the stereoscopic camera; - the first triangulation unit is further configured to generate a first reprojection error, RPE1, corresponding to the error between the PCO and a projection of the E3D on the CAE; - the Bundle Adjustment unit is configured to generate a refined calibration estimate, RCA, of the stereoscopic camera based on at least the PCO, the CAE and the E3D; - the second triangulation unit is configured to generate a second plurality of 3D object-point coordinates estimates, NE3D, based on at least the PCO and the RCA; - the second triangulation unit is further configured to generate a second reprojection error, RPE2, corresponding to the error between the PCO and a projection of the NE3D on the RCA; - the Bundle Adjustment unit is further configured to generate the refined calibration estimate, RCA, of the stereoscopic camera based on at least the PCO, the CAE and the NE3D; and, - the processing unit is further configured to determine a convergence criterion based on at least the RPE2 by iteratively generating the RCA and the RPE2, the convergence criterion being indicative of whether or not a camera calibration ground-truth has been found. - a processing unit configured to support at least a first triangulation unit, a second triangulation unit and a Bundle Adjustment unit, with respect to at least one stereo-image of the stereoscopic camera, wherein: - the first triangulation unit and second triangulation unit are coupled to the Bundle Adjustment unit; - the first triangulation unit is configured to generate a first plurality of 3D object-point coordinates estimates, E3D, based on at least a plurality of measured 2D image-point correspondences, PCO, of the stereo-image and an initial calibration estimate, CAE, of the stereoscopic camera; - the first triangulation unit is further configured to generate a first reprojection error, RPE1, corresponding to the error between the PCO and a projection of the E3D on the CAE; - the Bundle Adjustment unit is configured to generate a refined calibration estimate, RCA, of the stereoscopic camera based on at least the PCO, the CAE and the E3D; - the second triangulation unit is configured to generate a second plurality of 3D object-point coordinates estimates, NE3D, based on at least the PCO and the RCA; - the second triangulation unit is further configured to generate a second reprojection error, RPE2, corresponding to the error between the PCO and a projection of the NE3D on the RCA; - the Bundle Adjustment unit is further configured to generate the refined calibration estimate, RCA, of the stereoscopic camera based on at least the PCO, the CAE and the NE3D; and, - the processing unit is further configured to determine a convergence criterion based on at least the RPE2 by iteratively generating the RCA and the RPE2, the convergence criterion being indicative of whether or not a camera calibration ground-truth has been found.