共查询到20条相似文献,搜索用时 143 毫秒
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卫星遥感立体像对提取DEM是地貌信息获取的一个重要里程碑,ASTER卫星传感器是可以拍摄立体像对传感器中的代表,具有数据质量稳定、覆盖广泛、价格低廉的特点。本文通过实例研究了ASTER立体像对在高山峡谷地区提取DEM的精度。首先简述ASTER的立体像对提取DEM的国内外发展现状,然后针对一处高程变化显著地区在1:10万比例尺地形图采集地面控制点(GCP),用1:5万精度的DEM作检验,获得GCP范围内高程误差为±20.4m,GCP范围外高程误差为±48.2m,平均误差是±34.3m。这证明可以在小区域内选取GCP控制点,由ASTER立体像大范围外推生成大范围DEM,而且采用常规的技术手段和普通的商业软件就可实现。该方法提取DEM对于我国地形资料缺乏的西部地区有很强的实用性。 相似文献
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基于WorldView-2制备大野口流域高分辨率DEM及精度分析 总被引:1,自引:0,他引:1
在全野外GPS地面控制点基础上,对WorldView-2影像自带RPC文件进行校正,利用数字摄影测量软件系统在立体模型上通过影像自动匹配技术快速提取黑河流域上游大野口子流域1∶5 000比例尺数字高程模型(DEM)。由于区域地形复杂、交通不便,研究区南部无地面控制点覆盖。基于立体模型交互式操作,匹配60个均匀分布高精度影像连接点,提高了DEM自动提取精度。并在对阴坡森林覆盖区、大野口水库等重点区域进行DEM编辑基础上,辅助地形特征点和线数据提高了成果精度。由15个外业控制点、12个模型保密点组成的检查点进行定量DEM验证,结果表明:两组高程中误差最大为1.9 m,达到该比例尺山地一级精度2.5 m的要求。
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《遥感信息》2016,(6)
利用卫星热点监测森林火灾,在我国已有近20年的应用历史,但提高火场或火点定位精度的一直没有大的突破,经过系统级及GCP控制校正的监测图像,往往还存在2~4个像元的误差,影响了开展地面核查和处置的工作效率。针对以上问题,提出了一种基于90m DEM(数字高程模型)提取地性线,并集成立体可视地形地貌图、江河及大型湖泊矢量地图,以此为地理参照数据控制校正MODIS林火监测图像的方法。实验结果表明,与原有的几何纠正技术相比,利用地性线控制精校正的监测图像,其火场的定位误差从2~4个像元提高到1个像元内,GCP(控制点)的均方误差仅为431m,该技术方法能极大地提高卫星林火监测的几何精度。 相似文献
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合成孔径雷达干涉测量(InSAR)是获取数字高程模型(DEM)的常规手段,而通过干涉技术获得DEM后,其精度会受到轨道定位、影像的配准、干涉图获取、相位解缠等精度的影响。已有的利用区域网平差提升DEM精度的研究忽略了DEM的初始平面定位误差的影响。引入DEM的平面高程一体化区域网平差,将区域网平差分解为平面定位六参数的优化和高程误差模型的平差求解两个独立的平差过程,同时利用激光测高数据作为高程控制。从哨兵干涉生成的20 m分辨率DEM实验结果看,平差后DEM的高程均方根误差(RMSE)从平差前的19.372 m提升到了3.459 m。DEM对应连接点的平面内符合精度RMSE从初始182.462 m提升至14.887 m。而传统的不考虑平面误差的DEM优化方法在平差后高程精度提升至7.865 m,远低于所提出的方法,验证了提出的考虑平面误差的区域网平差方法的有效性。 相似文献
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基于高空间分辨率与立体像对遥感数据的建筑物三维信息提取 总被引:1,自引:0,他引:1
准确获取建筑的三维分布信息对于城市规划与管理、灾害风险评估与防范以及灾后救助等都具有非常重要的意义。针对目前建筑物信息提取研究集中于二维平面信息提取,三维信息提取研究较少,且方法自动化程度较低,实用性和和推广性不足,提出了综合立体像对和高空间分辨率两种遥感数据进行建筑物三维信息提取的方法。首先,基于小波变换融合方法对GeoEye\|1高空间分辨率全色和多光谱影像进行融合,然后运用面向对象方法对融合后的高空间分辨率遥感影像进行建筑物基底轮廓提取,再利用IRS\|P5立体像对反演地物高度,最后通过数据整合获得研究区建筑物的三维空间分布。研究结果表明:该方法可以充分利用不同遥感数据的优势,获得较高的提取精度;研究所需数据容易获取,方法具有较好的可操作性和推广性。 相似文献
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不同模式Radarsat 影像DEM 提取及精度比较 总被引:2,自引:0,他引:2
利用摄影测量方法进行DEM 提取是热带雨林地区雷达应用方向之一。以热带雨林地区平地、丘陵和山地混合地形区为研究对象, 收集了F、S 和W 等不同波束模式的Radarsat-1 SAR 影像9 景, 组合成6 个不同类型的立体像对, 进行DEM 提取, 探讨基于距离ö多普勒构像方程的Radarsat 影像的DEM 提取方法。通过对DEM 结果进行精度验证和比较, 认为提取的DEM 精度受多种因素影响, 同种波束模式的立体配置, 立体交会角越大,DEM 精度越高; 对于地表起伏较小的平地,DEM 精度要高于丘陵山地区, 该研究区DEM 精度的平均误差可以达到14 m 左右,RMSE 可以达到29 m 左右。 相似文献
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T. Toutin 《International journal of remote sensing》2013,34(22):5181-5192
A digital terrain model (DTM) extracted from QuickBird in-track stereo images using a three-dimensional (3D) multisensor physical model developed at the Canada Centre for Remote Sensing, Natural Resources Canada was evaluated. Firstly, the stereo photogrammetric bundle adjustment was set-up with about 10 accurate ground control points and 1-2 m errors in the three axes were obtained over 48 independent checkpoints. The DTM was then generated using an area-based multi-scale image matching method and 3D semi-automatic editing tools and then compared to lidar elevation data with 0.2-m accuracy. An elevation error with 68% confidence level (LE68) of 6.4 m was achieved over the full area. Since the DTM is in fact a digital surface model where the height, or a part, of land cover (trees, houses) is included, the accuracy depends on the land cover types. Using 3D visual classification of the stereo QuickBird images, different classes (deciduous, conifer, mixed and sparse forests, residential areas, bare soils and lakes) were generated to take into account the height of the surfaces (natural and human-made) in the accuracy evaluation. LE68 values of 3.4 m to 6.7 m were thus obtained depending on the land cover types with biases representative of the surface heights. On the other hand, LE68 values of 0.5 m and 1.3 m with no bias were obtained for lakes and bare soils respectively. These last results are more representative of the real stereo QuickBird potential for DTM and 5-m contour line generation, compliant with the highest topographic standard. Since the images were acquired in wintertime and the lidar data in summertime, better results could thus be expected when using stereo images acquired in summertime, mainly in deciduous forests to integrate the full canopy height into the DSM. 相似文献
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立体视觉中的双目匹配方法研究 总被引:12,自引:0,他引:12
本文首先对已有的双目立体视觉方法进行分析和总结 ,并依所选取的匹配特征和匹配方法的不同而将其分为利用灰度图像区域间相似性、特征点相关、边界或二阶导数过零点、二值拉普拉斯图像匹配、校正透视形变、动态规划、利用区域分割的结果和立体视觉连续性原理的各种演绎等类 ;然后对用金字塔图匹配边界基元的双目立体视觉方法进行了重点探讨 ;本文还对利用基极线约束实现匹配进行详细分析与推导 相似文献
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GeoEye-1 and WorldView-2 pan-sharpened imagery for object-based classification in urban environments 总被引:1,自引:0,他引:1
M.A. Aguilar M.M. Saldaña F.J. Aguilar 《International journal of remote sensing》2013,34(7):2583-2606
The latest breed of very high resolution (VHR) commercial satellites opens new possibilities for cartographic and remote-sensing applications. In fact, one of the most common applications of remote-sensing images is the extraction of land-cover information for digital image base maps by means of classification techniques. The aim of the study was to compare the potential classification accuracy provided by pan-sharpened orthoimages from both GeoEye-1 and WorldView-2 (WV2) VHR satellites over urban environments. The influence on the supervised classification accuracy was evaluated by means of an object-based statistical analysis regarding three main factors: (i) sensor used; (ii) sets of image object (IO) features used for classification considering spectral, geometry, texture, and elevation features; and (iii) size of training samples to feed the classifier (nearest neighbour (NN)). The new spectral bands of WV2 (Coastal, Yellow, Red Edge, and Near Infrared-2) did not improve the benchmark established from GeoEye-1. The best overall accuracy for GeoEye-1 (close to 89%) was attained by using together spectral and elevation features, whereas the highest overall accuracy for WV2 (83%) was achieved by adding textural features to the previous ones. In the case of buildings classification, the normalized digital surface model computed from light detection and ranging data was the most valuable feature, achieving producer's and user's accuracies close to 95% and 91% for GeoEye-1 and VW2, respectively. Last but not least and regarding the size of the training samples, the rule of ‘the larger the better' was true but, based on statistical analysis, the ideal choice would be variable depending on both each satellite and target class. In short, 20 training IOs per class would be enough if the NN classifier was applied on pan-sharpened orthoimages from both GeoEye-1 and WV2. 相似文献
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This study presents a building extraction strategy from High-resolution satellite stereo images (HRSSI) using 2D and 3D information fusion. In the 2D processing strategy, a visible vegetation index (VVI) is generated. In the 3D processing, a disparity map is generated using semi-global matching (SGM). To remove defects from the disparity map, an object-based approach is proposed by using mean-shift image segmentation and extracting rectangles. By removing terrain effects, a normalized disparity map (nDM) is produced. In the next step, vegetation pixels are removed from nDM and an initial building mask is generated. As nDM does not have precise building boundaries, hybrid segmentation by the kernel graph cut (KGC) is applied to the feature space including the RGB, nDM, and VVI and the results are used in a decision level fusion step. By this methodology, segments that are highly intersected with initial building mask are classified as buildings. Finally, a building boundary refinement (BBR) algorithm is applied to buildings for removing the remaining defects. The proposed method is applied to two pairs of GeoEye-1 stereo images including residential and industrial test areas. Evaluation results show the completeness and correctness level of higher than 90% for the two test areas. Further evaluations show that the quality metric has significantly changed after decision level fusion using the KGC. 相似文献
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立体视觉测量系统中,光学系统产生的畸变使目标的成像偏离了理论成像点,导致系统产生测量误差。针对提高系统测量精度的问题,提出一种基于立体视觉的测量方法。首先,根据标定板上各角点的像素分辨率,拟合整个成像平面的四次多项式,且多项式的系数与物体到相机的距离成比例;然后,应用双目测距原理,测量被测物体的纵向距离;最后,基于所得的多项式,应用单目相机测量待测物体的横向尺寸。实验结果表明,对于所提方法,当物体距离相机5 m以内时,其纵向距离误差可以减小到5%以内;当物体距离相机1 m时,其横向宽度测量误差在0.5 mm内,逼近理论最高分辨率。 相似文献
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为满足物流分拣的低成本和实时性要求,提出了基于多个立体摄像头的系统获取典型物体的完整立体信息的方法,并结合机械臂搭建了实验硬件平台。实验采用了2个微软Kinect摄像头在水平面上实现了约3 mm精度的物体定位,根据物体的立体信息建立立体模型,并计算了物体的取向、尺寸、含有的平面等多个可用于物体操作的立体特征,计算速率约为1 s/帧。根据这些信息,使用了机械臂成功进行了连续100次抓取。实验结果表明,这套方法和平台无需离线学习即可以实时提取多种尺寸和形状的物体的立体特征,机械臂可以基于此进行精度较高的物体操作。 相似文献
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T. ASTARAS N. LAMBRINOS N. SOULAKELLIS 《International journal of remote sensing》2013,34(9):1549-1559
Abstract Landsat-3 RBV, Landsat-5 TM imageries and SPOT PA stereopair diapositives were visually interpreted for the purpose of finding the accuracy of certain morphometric variables of three drainage basin sample areas in Central Macedonia, North Greece, drawn separately from each of the above three types of satellite imageries and comparisons were made between the efficiency of drainage systems drawn from each of the above imageries and the drainage systems extracted from the available topographic maps of 1:50000 scale. The main findings were the following: (1) SPOT PA stereopair diapositives of 1:200000 scale can be used to map drainage systems to an order of magnitude slightly more than TM imagery of 1:125000 scale, but significantly more than RBV imagery of 1:125000 scale. This slight superiority of SPOT imagery over TM imagery implies that the greater spectral range of TM, compared with the shorter range of SPOT imageries, vastly outweighs the advantage of SPOT'S superior resolution, but not the superiority of stereoscopic view; (2) TM imagery can be used to map drainage systems to an order of magnitude significantly more than RBV imagery; and (3) RBV imagery can be used to map drainage systems to an order of magnitude less than topographic maps of 1:50000 scale but better than topographic maps of 1:100000 scale. 相似文献