地球信息科学学报 ›› 2013, Vol. 15 ›› Issue (2): 249-254.doi: 10.3724/SP.J.1047.2013.00249

• 遥感科学与应用技术 • 上一篇    下一篇

遥感影像混合像元的分解——基于加权后验概率的支持向量机分类算法

许菡, 孙永华, 李小娟   

  1. 首都师范大学资源环境与旅游学院, 北京100048
  • 收稿日期:2012-11-08 修回日期:2013-02-18 出版日期:2013-04-25 发布日期:2013-04-18
  • 通讯作者: 李小娟(1965-),女,博士,教授,博士生导师,主要从事资源环境遥感动态监测、土地利用数据建库与更新、资源环境信息系统等基础与应用研究。E-mail:xiaojuanli@263.net E-mail:xiaojuanli@263.net
  • 作者简介:许菡(1979-),女,博士研究生,主要研究方向为遥感图像处理。E-mail:xuhan2009@gmail.com
  • 基金资助:

    国家“973”计划前期研究专项课题“城市典型区域不均匀沉降信息获取与机理研究”(2012CB723403)。

Unmixing of Remote Sensing Images Based onWeighted Posterior Probability Support Vector Machines

XU Han, SUN Yonghua, LI Xiaojuan   

  1. College of Resource Environment and Tourism, Capital Normal University, Beijing 100048, China
  • Received:2012-11-08 Revised:2013-02-18 Online:2013-04-25 Published:2013-04-18

摘要: 混合像元是遥感影像中普遍存在的现象, 对此, 本文提出基于加权后验概率的支持向量机进行影像混合像元分解。该分类算法可判定端元种类的同时得到每种地物的后验概率, 从而进行非线性模型的混合像元分解。由于加权后验概率的支持向量机分类算法能够减少分类器受土地覆盖类型模糊样本点的干扰, 因此, 改善了非线性混合像元分解模型的精度。首先, 由样本点计算得到核函数参数值, 然后, 计算影像中每一种土地覆盖类型的后验概率, 将其作为各个两类支持向量机分类器的权系数并求得多类后验概率值, 确定影像每一种土地覆盖类型并得到丰度值。本文采用TM 多波段遥感影像验证该方法的可行性, 实验区位于我国东北部的大兴安岭中北段地区, 土地覆盖类型包含农田、居民地、水体、荒地等。将本文提出的混合像元分解方法结果与标准支持向量机模型分解的结果对比表明, 以加权后验概率的支持向量机遥感影像混合像元分解方法精度优于标准支持向量机模型。

关键词: 加权后验概率, 支持向量机(SVM), 遥感影像, 分类, 混合像元分解

Abstract: Considering a lot of mixed image pixels are contained in remote sensing images, weighted posterior probability support vector machines are introduced to deal with the remote sensing images unmixing. Weighted posterior probability support vector machines aremotivated by statistical learning theory and is the further research result of regular SVM. Each ground posterior probability can be computed when training samples are determined by the proposed method. Non-linear unmixing mixed pixels model precision are improved by the method because weighted posterior probability support vector machines can avoid the effect on classifier than SVM. In order to solve the multi-class problem, two-class classification methods has been extended to multi-class classification methods and many algorithms have been developed. There are three classes can be described as following, one to many combination model, one to one combination model, and SVM decision tree. With weighted posterior probability support vector machines used on sub-pixel unmixing on remote sensing images, the classifier number are depressed than remote sensing images unmixing without weighted posterior probability support vector machines. The classification result based on weighted posterior probability support vector machines are more accurate according to empirical knowledge. Sample weighting is the main reason avoiding the negative effect of ambiguous ground class. The ground object endmembers can be determined by the proposed method and the posterior probability also be count out at the same time. The result of posterior probability is considered as the percent of each ground object belong to a pixel of remote sensing images. Multi-channel remote images data are used to validate the proposed method in this paper. The experiment results show that the unmixing model based on weighted posterior probability support vector machines has been improved over support vector machines algorithms. The precision of unmixing result obtained based on the proposed method is better than those of support vector machines algorithms.

Key words: unmixing pixels, weighted posterior probability, support vector machines (SVM), remote sensing image, classification