Chen Li Ping, Sun Yu Jun
State Forestry Administration Key Laboratory of Forest Resources & Environmental Management, Beijing Forestry University, Beijing 100083, China.
Ying Yong Sheng Tai Xue Bao. 2018 Dec;29(12):3995-4003. doi: 10.13287/j.1001-9332.201812.015.
Geographic Object-Based Image Analysis (GEOBIA) was a product under the background of increasing high-resolution remote sensing data. How to improve the accuracy and efficiency of classification of high-resolution images is one of the important topics in image processing. After objects segmented multiscale by QuickBird image was classified, the efficiency of C5.0, C4.5, and CART decision trees in object-oriented classification of forest areas was analyzed. The accuracy of those three methods were compared with kNN method. The eCognition software was used to multiscale segmentation of remote sensing images, with the result showing that 90 and 40 were the optimal scales. After separating vegetation and non-vegetation at 90 scale, 21 features such as spectrum, texture and shape of different vegetation types were extracted at 40 scale, knowledge mining was carried out by using C5.0, C4.5 and CART decision tree algorithms respectively, and classification rules were automatically established. The vegetation area was classified based on the classification rules and the classification accuracy of different methods was compared. The results showed that the classification accuracy based on decision-tree was higher than that of the traditional kNN method. The accuracy of C5.0 method was the best, with the overall accuracy and Kappa coefficient reaching 90.0% and 0.87, respectively. The decision tree algorithm could effectively improve the accuracy in classification of forest species. The Boosting algorithm of the C5.0 decision tree had the most significant improvement on the classification.
基于地理对象的图像分析(GEOBIA)是在高分辨率遥感数据不断增加的背景下产生的产物。如何提高高分辨率图像分类的准确性和效率是图像处理中的重要课题之一。对QuickBird影像多尺度分割后的对象进行分类后,分析了C5.0、C4.5和CART决策树在林区面向对象分类中的效率。将这三种方法的准确性与kNN方法进行了比较。利用eCognition软件对遥感影像进行多尺度分割,结果表明90和40为最优尺度。在90尺度上分离植被和非植被后,在40尺度上提取不同植被类型的光谱、纹理和形状等21个特征,分别采用C5.0、C4.5和CART决策树算法进行知识挖掘,自动建立分类规则。基于分类规则对植被面积进行分类,并比较不同方法的分类精度。结果表明,基于决策树的分类精度高于传统的kNN方法。C5.0方法的精度最好,总体精度和Kappa系数分别达到90.0%和0.87。决策树算法能有效提高森林树种分类的准确性。C5.0决策树的Boosting算法对分类的提升最为显著。