Extracting distorted grid points for compensation of lens radial nonlinearities

A novel method for extracting distorted grid points for compensation of lens radial nonlinearities is presented. It is based on identification of homographic transformation using single image of dense planar chessboard pattern. Undistorted grid image is determined from the central part of the grid and used to find the radial distortion model by linear least square method (LSM). The model is used for dense compensation by bilinear interpolation.