Abstract: A new visibility auto-calculation method based on the edge of images is proposed.Firstly，the visibility definition of the atmospheric sciences is simplified.Then these inherent features for the landmark boundary region，such as gradient，contrast，brightness etc，are extracted and used to calculate visibility with the simplified definition.Finally，according to a preset threshold the visibility of landmark is quantitatively determined and visibility calculating is implemented.In this paper a system model for visibility auto-calculation is built，comparing the data between experiments and the actual observation，the feasibility and the effectiveness of the method is verified，in comparison with other methods，the method has improved significantly in the reliability and effectiveness for the calculation.

Key words: visibility, edge, gradient, contrast, brightness

摘要： 一种新的基于图像边缘处理的能见度自动计算方法被提出。它首先对大气科学中定义的能见度进行简化，接着对地面标记物边界区域提取边缘梯度、对比度、亮度等图像内在特征并针对这些特征利用简化的能见度定义进行计算，最后根据预定义的阈值定量地判定地面预设标志物的可见性从而实现计算能见度。一个能见度自动计算系统模型被建立，通过实验与实际观察结果的数据对比，验证了其算法的可行性和有效性，与已有算法相比其算法在计算的可靠性和有效性方面具有明显改善。

关键词: 能见度, 边缘, 梯度, 对比度, 亮度