Abstract: In this paper the planar constraints are reviewed and the relationship of the antisymmetry and the planar constraints for two perspective images is discussed And given a set of correspondent points in a plane in two images, a robust improved algorithm is proposed to transform the problem of calculating the homography matrix in the process of camera self calibration with the planar constraints to a quadratic programming problem And then the intrinsic parameters can be calculated with the planar constraints and the extrinsic parameters can be calculated using the relationship between the essential matrix and the fundamental matrix The experimental results show that the algorithm is robust