冠层孔隙度是计算林冠叶面积指数的重要参数之一,对冠层生长情况的评价起到至关重要的作用。为合理获取林冠孔隙度值,本文提出利用Matlab对半球型冠层图像进行分析。提取RGB图像单一颜色分量,将提取后的图像进行分割获取有效区域,再利用改进的OTSU算法提取其像素点信息并进行计算得到孔隙度值,将该值与Winscanopy处理结果对比表明,两者具有较高的相关性。本文提出的计算方法为有效获取冠层孔隙度开辟了新途径。
Canopy gap fraction is one of the important parameters of leaf area index calculation,playing a crucial role in evaluating canopy growth.In this paper,MATLAB is applied to analyze hemispherical photographs to obtain reasonable values of canopy gap fraction.After extracting the single color component,the photographs are segmented to get effective area,then information of every pixel is extracted and calculated to get values of canopy gap fraction through using improved OTSU algorithms.By contrasting values of canopy gap fraction with processing results of Winscanopy,it can draw a conclusion that correlation of both sides is very high.The proposed calculation method opens up new avenues for effectively getting canopy gap fraction.
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