Abstract: Non-measuring cameras are widely used in high-precision measurement because of their low price, small size and flexible use. However, camera calibration results have a great influence on the measurement accuracy, and the existing camera calibration methods have some problems such as insufficient accuracy or low efficiency. In this paper, a camera calibration method combining features from accelerated segment test (FAST) and double image beam adjustment is proposed. Firstly, the FAST algorithm was used to extract the marks automatically, and the initial values of the internal and external parameters of the camera were obtained by direct linear transformation method. Then, the relative parameters of the camera were calculated by the double image beam adjustment model based on the fixed baseline length constraint, and the convergence efficiency of the model was improved by the classification threshold method. The experimental results show that the proposed method has improved the accuracy of adjustment compared with the ordinary double image beam method, and the calibration error reaches 0.0064 mm. Moreover, the semi-automatic camera calibration process is realized, and the operation efficiency is improved. It is expected to be applied to the actual camera calibration operation.
Keywords: camera calibration; double image beam method; adjustment model; features from accelerated segment test(FAST) algorithm