Using Direction of Longest Line Segment for Aerodrome Forward-looking Scene Matching

As conventional down-looking matching methods can not overcome perspective transmutation of forward-looking imaging, a new method based on computing direction of longest line segment from image pair is advanced for aerodrome forward-looking scene matching. Considering line feature of runway is distinct and not sensitive to perspective transmutation, firstly use Hough idea to extract longest line segment both from reference image and real-time image. Then, compute the angle difference to restore reference image before matching algorithm can be done. Results show that the method can make full use of image information and has a good ability of aerodrome positioning, especially when image pair exists biggish rotation, and it can be a first try for research of forward-looking scene matching.