针对以往无人机遥感用于城市植被分类时多利用影像光谱、纹理和形状等特征,影像重建点云数据未能充分利用的问题,提出一种综合影像重建点云与光谱信息的城市植被分类方法。首先,基于运动恢复结构(structure from motion,SFM)、多视图聚...针对以往无人机遥感用于城市植被分类时多利用影像光谱、纹理和形状等特征,影像重建点云数据未能充分利用的问题,提出一种综合影像重建点云与光谱信息的城市植被分类方法。首先,基于运动恢复结构(structure from motion,SFM)、多视图聚簇(cluster multi view stereo,CMVS)和基于面片模型的密集匹配(patch based multi view stereo,PMVS)算法重建研究区密集点云;然后,经滤波、插值生成研究区数字高程模型(digital elevation model,DEM)和归一化数字表面模型(normalized digital surface model,n DSM),同时结合影像光谱信息对不同高度的城市植被进行分类提取;最后,采用面向对象的影像分析方法,根据n DSM信息与归一化绿红差异指数(normalized greenred difference index,NGRDI)及可见光波段差异植被指数(visible-band difference vegetation index,VDVI)等光谱信息,分别建立了水生植被、草地、灌木、小乔木和乔木等不同植被的分类规则。实验结果表明综合利用影像重建点云得到的n DSM信息与影像光谱信息提取不同高度的植被是可行的,总体分类精度达到92. 08%。该方法可为城市植被分类与制图提供理论支持和应用参考。展开更多
An object oriented coal mining land cover classification method based on semantically meaningful image segmentation and image combination of GeoEye imagery and airborne laser scanning (ALS) data was presented. First, ...An object oriented coal mining land cover classification method based on semantically meaningful image segmentation and image combination of GeoEye imagery and airborne laser scanning (ALS) data was presented. First, DEM, DSM and nDSM (normalized Digital Surface Model, nDSM) were extracted from ALS data. The GeoEye imagery and DSM data were combined to create segmented objects based on neighbor regions merge method. Then 10 kinds of objects were extracted. Different kinds of vegetation objects, including crop, grass, shrub and tree, can be extracted by using NDVI and height value of nDSM. Water and coal pile field was extracted by using NDWI and the standard deviation of DSM method. Height differences also can be used to distinguish buildings from road and vacant land, and accurate building contour information can be extracted by using relationship of neighbor objects and morphological method. The test result shows that the total classification accuracy of the presented method is 90.78% and the kappa coefficient is 0.891 4.展开更多
通过激光雷达数据反演林木参数,特别是树高,将极大地推进激光雷达在林业上的应用。本文首先对LiDAR获取的高密度点云进行预处理,生成适合森林参数提取的规则网格数字表面模型,然后利用形态学滤波的方法逐步去掉非地形要素,形成数字高程...通过激光雷达数据反演林木参数,特别是树高,将极大地推进激光雷达在林业上的应用。本文首先对LiDAR获取的高密度点云进行预处理,生成适合森林参数提取的规则网格数字表面模型,然后利用形态学滤波的方法逐步去掉非地形要素,形成数字高程模型,最后利用数字表面模型减去得到的数字高程模型,可得到正则化数字表面模型,并求出地物的相对高度信息,在林木上就是最终得到所需要的树木平均高度信息。结合真实LH System ALS40数据进行实验,验证了本文方法的可行性。展开更多
无人机的出现,给生态调查带来关键性革新。而使用无人机进行生态调查,植物遥感分类是关键,基于平地的无人机植物物种分类创新运用于边坡,使用可见光正射影像联合nDSM(normalized digital surface model,归一化数字表面模型)对边坡植物...无人机的出现,给生态调查带来关键性革新。而使用无人机进行生态调查,植物遥感分类是关键,基于平地的无人机植物物种分类创新运用于边坡,使用可见光正射影像联合nDSM(normalized digital surface model,归一化数字表面模型)对边坡植物物种进行分类。结果表明,边坡样地的分类的精度达85%,自然样地达84%,与没有加入nDSM的分类结果对比,边坡、自然样地分类精度分别增加了32%和16%。在边坡条件下可见光正射影像与nDSM结合,可大幅度提升边坡植物物种分类精细度。展开更多
文摘针对以往无人机遥感用于城市植被分类时多利用影像光谱、纹理和形状等特征,影像重建点云数据未能充分利用的问题,提出一种综合影像重建点云与光谱信息的城市植被分类方法。首先,基于运动恢复结构(structure from motion,SFM)、多视图聚簇(cluster multi view stereo,CMVS)和基于面片模型的密集匹配(patch based multi view stereo,PMVS)算法重建研究区密集点云;然后,经滤波、插值生成研究区数字高程模型(digital elevation model,DEM)和归一化数字表面模型(normalized digital surface model,n DSM),同时结合影像光谱信息对不同高度的城市植被进行分类提取;最后,采用面向对象的影像分析方法,根据n DSM信息与归一化绿红差异指数(normalized greenred difference index,NGRDI)及可见光波段差异植被指数(visible-band difference vegetation index,VDVI)等光谱信息,分别建立了水生植被、草地、灌木、小乔木和乔木等不同植被的分类规则。实验结果表明综合利用影像重建点云得到的n DSM信息与影像光谱信息提取不同高度的植被是可行的,总体分类精度达到92. 08%。该方法可为城市植被分类与制图提供理论支持和应用参考。
基金Project(2009CB226107)supported by the National Basic Research Program of China
文摘An object oriented coal mining land cover classification method based on semantically meaningful image segmentation and image combination of GeoEye imagery and airborne laser scanning (ALS) data was presented. First, DEM, DSM and nDSM (normalized Digital Surface Model, nDSM) were extracted from ALS data. The GeoEye imagery and DSM data were combined to create segmented objects based on neighbor regions merge method. Then 10 kinds of objects were extracted. Different kinds of vegetation objects, including crop, grass, shrub and tree, can be extracted by using NDVI and height value of nDSM. Water and coal pile field was extracted by using NDWI and the standard deviation of DSM method. Height differences also can be used to distinguish buildings from road and vacant land, and accurate building contour information can be extracted by using relationship of neighbor objects and morphological method. The test result shows that the total classification accuracy of the presented method is 90.78% and the kappa coefficient is 0.891 4.
文摘通过激光雷达数据反演林木参数,特别是树高,将极大地推进激光雷达在林业上的应用。本文首先对LiDAR获取的高密度点云进行预处理,生成适合森林参数提取的规则网格数字表面模型,然后利用形态学滤波的方法逐步去掉非地形要素,形成数字高程模型,最后利用数字表面模型减去得到的数字高程模型,可得到正则化数字表面模型,并求出地物的相对高度信息,在林木上就是最终得到所需要的树木平均高度信息。结合真实LH System ALS40数据进行实验,验证了本文方法的可行性。
文摘无人机的出现,给生态调查带来关键性革新。而使用无人机进行生态调查,植物遥感分类是关键,基于平地的无人机植物物种分类创新运用于边坡,使用可见光正射影像联合nDSM(normalized digital surface model,归一化数字表面模型)对边坡植物物种进行分类。结果表明,边坡样地的分类的精度达85%,自然样地达84%,与没有加入nDSM的分类结果对比,边坡、自然样地分类精度分别增加了32%和16%。在边坡条件下可见光正射影像与nDSM结合,可大幅度提升边坡植物物种分类精细度。
