This report provides a detailed study of the problem of real time camera calibration. This analysis, based on the study of literature in the area, as well as the experiments carried out on real and synthetic data, is motivated by the requirements of the VISTEO project. VISTEO deals with a fusion of real images and synthetic environments, objects etc in TV video sequences. It thus deals with a challenging and fast growing area in virtual reality research - Augmented reality (AR). AR generates a composite view of the real scene viewed by the user and a virtual scene generated by the computer which augments the real scene with additional information.