Image-based Distance Measurement Method Study

The image-based measurement technique is one kind of novel noncontact measurement technique, which develops from the computer vision realm and primarily regards images as the carrier and means to detect or transfer the information. The image-based measurement technique can bring us the actual information of the examined object after dealing with the characters detected from the images. Moreover, this measurement technique has very strong adaptability in the aspects of accuracy, speed, intelligence and so on. Combining its high accuracy and good stability with the mature technique of image process, this measurement technique can be immediately applied in the practical measurement system and make it have the better automation ability. Therefore, the image-based measurement technique can be used to extremely extensive field, such as: computer vision, universe remote sensing, the manufacture of the super or large-scale integrated circuit and the on-linely measure of the industry spot.This paper is based on the projective geometry of computer vision and mainly made the research on the image-based distance measurement problems. The main research achievements are shown as the following:1. Developed from the theory of projective geometry, this paper made a detailed research on the basic theory of the image-based plane measurement technique. All kinds of methods about the key homography matrix have been fully discussed. And each method has been given the result of simulate and actual experimentation. After that, a practical application was introduced.2. After the discussion of the plane measurement, we continue the discussion about the important method of the stereo measurement, such as: the method of resolving the fundamental matrix, the method of recovering the fundamental matrix from the camera matrix, the method of recovering the 3D point based on the trigonometry. After that, the result of actual experiment was shown.3. At finally, this paper made some discussion about several problems that related tothe image-based distance measurement, such as: the dense stereo matching based on epipolar constraint and edge points detecting, the method for height measure based on single image.