一种超像素上Parzen窗密度估计的遥感图像分割方法

Remote sensing image segmentation based on Parzen window density estimation of super-pixels

图像分割是高分辨率遥感图像分析中的关键步骤,对信息提取精度起到重要作用。为提高传统基于像素的遥感图像分割算法性能,提出一种在超像素上进行Parzen窗密度估计的分割算法。包括超像素初始分割、特征测量、密度估计并重新聚类3个主要步骤。在超像素初始分割阶段,采用简单线性迭代聚类算法将图像进行超像素粗分割,并将每个超像素块标记为图结构中的一个顶点;然后测量每个超像素块的Gabor纹理特征,构建高维特征向量并计算纹理间的相似度,作为图中连接2个顶点的边的权值,并在该图的最小生成树上计算2个顶点之间的距离;接着将此距离用于Parzen窗,估计每个顶点的密度,并重新聚类得到最终结果。采用多幅多光谱高分辨遥感图像验证本文提出的算法,基于目视判别以及基于准确率和召回率的定量评价,将该方法与其他分割算法的结果进行比较,验证了提出算法的有效性。

Image segmentation is a key step in the analysis of high-resolution remote sensing images and plays an important role in improving information extraction accuracy.To improve the performance of traditional pixel-based image segmentation methods,this study proposed a new algorithm based on Parzen window density estimation of super-pixel blocks.The new algorithm includes three main steps,namely super-pixel initial segmentation,feature measurement,and density estimation and re-clustering.In the first step,an image is coarsely divided using the simple linear iterative clustering(SLIC)algorithm,and each super-pixel block is marked as a node in the graph structure of the image.In the second step,the Gabor texture features of each super-pixel block are measured to construct high-dimension feature vectors.Meanwhile,the similarity of the image textures is calculated as the weight of the edge connecting two nodes in the graph.Then,the distance between the two nodes is calculated on the minimum spanning tree(MST)of the graph.In the third step,the calculated distance is used for Parzen window density estimation of each node,and re-clustering of the density values is conducted to obtain the final results.In the experiments,multiple multispectral high-resolution remote sensing images were adopted to verify the algorithm proposed in this study.Using visual discrimination and the quantitative evaluation based on precesion rate and recall rate,the segmentation results of the algorithm proposed in this study were compared with those of other algorithms.The experiments verified that the algorithm proposed in this study is effective.