A Method Based on Two Constraints for Camera Calibration Interior Parameters

In the digital photogrammetry system, camera calibration is an essential part and its accuracy directly affects system accuracy. Because non-metric digital camera interior parameters are the stationary in the measurement process, the camera interior parameters should be accurately calibrated in the laboratory. Considering the lack of general DLT algorithm, we adopt nonlinear model of the camera based on distortion. And two additional constraints are used to accurately calibrate the parameters of the camera. The experimental results are analyzed and compared with the V-STARS system. The results of interior parameters calibration are less than 1 pixel. Test results meet the requirements of industrial digital photogrammetry.