利用云导风矢量的台风中心自动定位

文中提出了一种利用云导风矢量图进行台风中心自动定位的方法。云导风矢量通过对具有一定时间间隔的两幅相关卫星云图进行模板匹配而得出。模板匹配就是根据已知模式的图像在一幅陌生图像中寻找对应于该模式的子图像的过程。根据气象知识 ,台风云系运动的特点是中心平移量大而自旋很弱 ,且台风中心与台风云系整体的移动方向一致 ,因此求出云导风矢量图中与台风整体移动矢量大小和方向一致的矢量集合的最密集区 ,经过数学形态学处理后便得到台风中心

AUTOMATIC LOCATION OF TYPHOON CENTER USING CLOUD DERIVED WIND VECTORS

An automatic locating algorithm is presented for typhoon center using cloud motion wind vectors derived from the satellite cloud images. The cloud motion wind vectors are obtained by implementing template matching to a pair of interrelated satellite cloud images with vegulan time interval. The template matching is a process to find the child image that corresponds to the given pattern image in an unknown pattern image. Three matching algorithms are compared. Namely, the absolute difference matching algorithm, the sequential similarity detection algorithm and the infrared cross-correlation coefficients matching algorithm. The third one is selected to acquire the set of cloud motion wind vectors due to its desirable vector results. Aiming at the specific typhoon cloud image, two simplifications are processed in the course of acquiring the cloud motion wind vectors. According to meteorological analysis, typhoon center motion has two important characteristics: (1) The translation in the central area is great while the spin is feeble. (2) The center moving direction is compatible to that of the whole typhoon clouds. According to these characteristics, the algorithm for automatically locating the typhoon center can be depicted as follows: firstly pick up the vectors that compatible to the whole typhoon cloud motion vectors in the cloud motion wind vectors image, then find out the thickest area of the satisfied vectors, lastly process the thickest area with mathematical morphology until there exists only one pixel point. The locating result shows that the thought in the paper is good and can be a promising application in the typhoon center location field.