【摘要】 日食现象的发生,使得卫星可见光云图上会出现明显的阴影区,在阴影区内云图的信息无法得到分析和利用。首先阐述了日食发生的原理,由此给出阴影区内卫星接收到地球表面的辐射的订正函数,然后用该辐射订正函数对日食阴影区进行订正处理。立足于图像处理的观点,利用图像的灰度共生矩阵、纹理特征量评价可见光云图日食阴影的订正效果。结果表明,所用的订正方法是有效的,订正前后灰度共生矩阵、云图的对比度和熵的改变说明日食阴影已基本被消除,云系纹理、结构变得清晰,而订正前后云图的相关保持基本不变。更多还原

【Abstract】 Solar eclipse would result in an obvious shadow on satellite VIS imagery. In the shadow, the type and the shape of cloud can not be distinguished correctly, which would have impact on analyzing and applying the information of the satellite VIS imagery in practice, so it is very important to eliminate the eclipse shadow. In this paper, the theory of solar eclipse is given at first and then the radiant revisal function, which the satellite can receive the radiation from the earth, is given. Using the radiant revisal function, the eclipse shadow can be eliminated. Based on the point of image manipulation, using the gray level coocurrence matrix and cloud texture feature quantities, such as contrast, entropy and correlation, the effect of the solar eclipse elimination can be estimated. The results show that the method is more effective, the alteration of the gray level coocurrence matrix and the contrast and the entropy indicated that the shadow has been eliminated primarily, the texture and structure of cloud system are trenchanter than before , while the correlation of cloud system keeps unchanged.更多还原