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.