Comparation of calibration methods for bubbly flow video image

Bubble flow video imaging device uses two high speed cameras to capture the bubble rising process in a transparent still sink. Tsai´s two step calibration method, Zhang Zhengyou calibration method, Camera Calibration Toolbox for Matlab are selected to do the calibration experiments on the high speed cameras. Each calibration method gives a different calibrated model. The accuracy of different model is compared. It´s proved that Zhang´s calibration method gives the most accurate model in this experiment. The fundamental of different calibration methods are given at the beginning. The calibrated model given by Zhang´s method is used to revise bubble parameters extracted from bubble flow images.