Extraction And Representation Of Spiral Band And Center Location For Developing Typhoon

Of all natural disasters, typhoon poses the most dangerous threat to life and property. It is very important to recognize typhoon and locate the center through satellite image. But the work is still in research due to the complex nature of cloud shape and structure of typhoon.The main targets are extraction and representation of spiral band and center location for developing typhoon in the paper. Using techniques of Computer Vision, integrated expert experience, feature extrication on incomplete spiral band gain successes; and results of center location are satisfactory. First spiral band extraction is performed on the basis of cloud image segmentation. A principal curve is used to represent the shape feature of every region. Then Hough transform is applied to these curves to detect a logarithm spiral equation which can match the curves well. To achieve the goal, coordinates transform is employed to reduce the parameter dimension of Hough transform. After the spiral is obtained, locate the typhoon center on the center of the spiral. Another algorithm of curve imitation directly is put forward. Through curve imitation on single spiral pieces or two pieces that can be connected for many times, the center position is obtained by synthesizing the imitation results. Cloud image sequences may reflect the motion of clouds. It has the advantage over single image in typhoon prediction. In the paper, existing cloud motion wind algorithm is improved for embodying the motion tendency of small cloud details. Motion vectors are categorized into 16 different directions. Bisected the image into four quadrants according to the typhoon center, the number of motion vectors satisfied the correct motion conditions should reach the maximum. According to the fact, the motion vector image is used to locate the typhoon center. The algorithms in the paper extract shape and motion feature successfully and apply in center location. The research results will play an important part in system of typhoon automatic recognition and location.