Improved Harris sub-pixel corner detection algorithm for chessboard image

Control point image locating accuracy of calibration plate is one of the major factors which determine the accuracy of camera calibration. Thus we can improve determine the accuracy of camera calibration by improve the control point image locating accuracy of calibration plate. And an improved Harris sub-pixel corner detection algorithm is put forward to improve the control point image locating accuracy. Initial location of corner point using Harris corner detection algorithm is implemented at first, and then improved Harris corner detection algorithm is used to realize sub-pixel locating accuracy. Corner points' coordinate values are gotten by means of initial location and fine location. The result of examine show that corner detection precision is improved greatly through improved Harris sub-pixel corner detection algorithm of chessboard image, and realize the sub-pixel corner detection.