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1.
Referring to the high potential of topographic satellite in collecting high resolution panchromatic imagery and high spectral, multi spectral imagery, the purpose of image fusion is to produce a new image data with high spatial and spectral characteristics. It is necessary to evaluate the quality of fused image by some quality metrics before using this product in various applications. Up to now, several metrics have been proposed for image quality assessment; which are also applicable for quality evaluation of fused images. However, it seems more investigations are needed to inspect the potentials of proposed Image Fusion Quality Metrics (IFQMs) to registration accuracy, especially in high resolution satellite imagery. This paper focuses on such studies and, using different image fusion quality metrics, experiments are conducted to evaluate the sensitivity of such metrics to a set of high resolution satellite imagery covering urban areas. The obtained results clearly reveal that these metrics sometimes do not behave robust in the whole area and also their obtained results are inconsistence in different patch areas in comparison with the whole image. These limitations are in minimum situation for an image quality metric such as SAM and are completely tangible for image quality metrics such as ERGAS in case of multi modal and DIV and CC from mono modal category.  相似文献   

2.
将卫星雷达遥感应用于滑坡灾害的探测与监测,不仅可以从空间尺度上大范围捕捉到滑坡信号,而且可以从时间尺度上以较长周期追踪滑坡的运动状态。但是,卫星雷达遥感本身的局限性和滑坡所处的复杂地形环境使这一应用面临一些挑战。对卫星雷达遥感技术的4个主要挑战进行了总结与分析,同时给出了相应的解决方案:①通过提高卫星雷达影像的空间、时间分辨率,使用较长波段雷达信号或采用增强型时间序列分析技术,可降低密集植被覆盖对相干性的影响。另外,采用像素点偏移量追踪或距离向分频干涉测量方法,可克服传统干涉测量中大梯度形变引起的相位失相干。②大气延迟对卫星遥感的影响较大,尤其是地处山区的滑坡探测和监测,利用通用型卫星雷达大气改正系统可显著减弱干涉影像的大气信号并进一步简化时间序列分析,提高缓慢运动滑坡的探测和监测质量。③对于中等分辨率的雷达影像而言,利用数字高程模型可提前量化分析雷达几何畸变(如叠掩、阴影等)引发的滑坡探测监测的适用性;而对于高分辨率的雷达影像而言,利用机器学习方法无需外部高分辨率数字高程模型即可精确识别雷达影像的阴影和叠掩区并进行掩膜,从而大幅度提高数据处理效率。④针对高坡度地区残余的地形相位引起的解缠误差,可通过基线线性组合的方法予以减弱。此外,提出了一个基于多源对地观测的滑坡探测/监测系统框架,综合卫星雷达遥感与其他对地观测数据(如地基雷达、激光雷达、全球导航定位系统),搭建了一个自动化滑坡探测与监测系统。该研究旨在阐明卫星雷达遥感的优缺点,进一步深化其在滑坡灾害监测方面的应用和推广,引出未来侧重发展方向的思考与探讨。  相似文献   

3.
Global precipitation is monitored from a variety of platforms including spaceborne, ground-, and ocean-based platforms. Intercomparisons of these observations are crucial to validating the measurements and providing confidence for each measurement technique. Probability distribution functions of rain rates are used to compare satellite and ground-based radar observations. A preferred adjustment technique for improving rain rate distribution estimates is identified using measurements from ground-based radar and rain gauges within the coverage area of the radar. The underwater measurement of rainfall shows similarities to radar measurements, but with intermediate spatial resolution and high temporal resolution. Reconciling these different measurement techniques provides understanding and confidence for all of the methods.  相似文献   

4.
With the availability of very high resolution multispectral imagery, it is possible to identify small features in urban environment. Because of the multiscale feature and diverse composition of land cover types found within the urban environment, the production of accurate urban land cover maps from high resolution satellite imagery is a difficult task. This paper demonstrates the potential of 8 bands capability of World View 2 satellite for better automated feature extraction and discrimination studies. Multiresolution segmentation and object based classification techniques were then applied for discrimination of urban and vegetation features in a part of Dehradun, Uttarakhand, India. The study demonstrates that scale, colour, shape, compactness and smoothness have a significant influence on the quality of image objects achieved, which in turn governs the classified result. The object oriented analysis is a valid approach for analyzing high spatial and spectral resolution images. World View 2 imagery with its rich spatial and spectral information content has very high potential for discrimination of the less varied varieties of vegetation.  相似文献   

5.
This paper is the first ever attempt to study population distribution in Al Ain city in Eastern United Arab Emirates (UAE) through integration of remote sensing and Geographic Information System (GIS). The remote sensing data used in this study included high spatial resolution (1 m) IKONOS imagery of February 17, 2001. For the population related studies IKONOS data offers number of advantages over other satellite images, e.g. it has high spatial resolution, it covers a larger area per image, it cost less per km2, and available on a more regular basis. Such characteristics provide a mechanism by which population estimates can be updated with high accuracy and better rate of frequency. The average difference between the population recorded in the 2001 and that estimated from IKONOS images for Al Ain city is found to be equal to 5%. GIS is used for modelling the relationship among population variables and shows result obtained. Empirical model analyses results of this study show that the overall density of the city is consistent with location theories, i.e., declining population density from the Central Business District (CBD). The trend of higher-income people living in peripheries of cities is evident worldwide as it is in Al Ain.  相似文献   

6.
高分辨率影像解译理论与应用方法中的一些研究问题   总被引:36,自引:4,他引:36  
宫鹏  黎夏  徐冰 《遥感学报》2006,10(1):1-5
近年来,不断发展的遥感技术使遥感数据呈现出高空间分辨率、高光谱分辨率和高时间采集频率的特点。卫星图像空间分辨率已经提高到0.6m级,而航空遥感数字影像分辨率高达0.1m以上。光谱分辨率高达3—4nm。不断发展的高分辨率遥感数据能够提高信息提取和监测精度,并拓展遥感数据的应用范围。目前,国外已经加快对高分辨率图像,特别是高空间分辨率影像,在城市环境、精准农业、交通及道路设施、林业测量、军事目标识别和灾害评估中的应用。但是总的情况是自动化程度不高。介绍高空间分辨率影像信息提取、高光谱和偏振影像信息提取、影像数据融合和高分辨率遥感变化探测等方面迫切需要研究的一些科学问题及其意义。建议建立图像知识库,改善数据共享环境,为有志于从事这方面研究的学者提供参考。  相似文献   

7.
与现有的大气卫星传感器相比,环境一号卫星(HJ-1)CCD相机具有较高的空间分辨率(30m),使得在城市地区找到光谱纯像元的机率大大增加。本文提出一种基于纯像元提取的城市地区气溶胶光学厚度(AerosolOpticalDepth,AOD)反演算法,利用像元纯净指数来提取CCD影像上的纯像元,并由HJ-1A星和B星的多时相CCD观测数据结合地表双向反射率模型确定纯像元的地表反射特性,在此基础上反演AOD。与AERONET地基测量数据的对比表明,该算法具有较高精度,相关系数为0.83,线性拟合斜率为1.091,截距为0.053。基于该方法的AOD反演结果作为输入,能较大程度提高HJ-1卫星CCD影像大气校正的精度。  相似文献   

8.
支撑向量机及其遥感影像空间特征提取和分类的应用研究   总被引:38,自引:3,他引:38  
提出了基于支撑向量机(SVM)的遥感影像空间特征提取的新方法,并以SPOT全色波段影像上城市特征信息的提取为应用实例,并与人工神经网络(ANN)等特征提取方法进行综合比较,认为SVM方法不但能够获得比较高的分类精度,而且在学习速度、自适应能力、特征空间高维不限制、可表达性等方面具有优势。  相似文献   

9.
The rapid growth of urban population in India is a cause of concern among country??s urban and town planners for efficient urban planning. The drastic growth of urban areas has resulted in sharp land use and land cover changes. In recent years, the significance of spatial data technologies, especially the application of remotely sensed data and geographical information systems (GIS) has been widely used. The present study investigates the urban growth of Tiruchirapalli city, Tamilnadu using IRS satellite data for the years 1989, 1992, 1995, 1998, 2001, 2004, 2007, and 2010. The eight satellite images are enhanced using convolution spatial enhancement method with Kernel (7?×?7) edge enhance function. Supervised classification method is used to classify the urban land use and land cover. The GIS is used to prepare the different layers belonging to various land uses identified from remotely sensed data. The analysis of the results show the drastic increase of built up area and reduced green cover within the city boundary limit.  相似文献   

10.
Any underground excavation or depletion of either solid minerals or liquids may lead to deformation of the surface profile for areas present above these underground zones. The awareness of deformation rate or rate of change of the natural surface is very important for proper planning and utilization of the geo-resources. These often suffer from the limitations of proper methods of data capture in such areas, accessible or in-accessible to the human beings; in terms of the data density, the time involved in the data capturing process and the associated risks in doing so. Once a proper data is captured, it may easily be used to generate the models of the geo-structures present in and around the region of interest. Till date, the conventional methods of surveying, like precise leveling or GPS, were used for the data capture, which are point observations and suffer from disadvantages like limited spatial resolution, large data capture time, easy manipulability of the collected data, high risk for the operators involved, high cost for large areas etc. With the advent of newer and advanced techniques of data capture in geo-information; use of high precision satellite imagery, especially the synthetic aperture radar (SAR) data having the complex information (i.e. the phase as well as amplitude), has been found to provide adequate data for such purposes. Interferometric synthetic aperture radar (InSAR) is a technique used to reconstruct the digital elevation models (DEM) of the observed scenes. Determination of the surface deformation profiles, integrating the surface displacements using the GIS tool (GRASS) and verification of the surface displacement rates become the main objectives of the present paper. It has been observed that the values of the displacement rates computed using the new method match closely with those obtained using the conventional methods of surface data capture techniques. It has also been found that the new method has several advantages over the conventional methods, as discussed later in this paper.  相似文献   

11.
高分辨率卫星遥感数据在城市地图更新中的应用   总被引:2,自引:0,他引:2  
城市地图是全面反映城市发展和城市社会经济现象的综合信息载体,是城市基础空间数据库和城市GIS的重要组成部分。文章就高分辨率卫星遥感数据在城市地图更新中的工艺、生产平台、影像纠正、影像融合、地图更新的方法及应用进行了探讨。  相似文献   

12.
Abstract

The paper discusses the potential of very high resolution (VHR) satellite imagery for post-earthquake damage assessment in comparison with the role of aerial photographs. Post-disaster optical and radar satellite data are assessed for their ability to resolve collapsed buildings, destroyed transportation infrastructure, and specific land cover changes. Optical VHR imagery has shown to be effective in quantifying building stock and for assessing damage at the building level. High-resolution synthetic aperture radar (SAR) imagery requires further research to identify optimum information extraction procedures for rapid assessment of affected buildings. Based on current technical and operational capabilities increasing efforts should be devoted to the generation of spatial datasets for disaster preparedness.  相似文献   

13.
TRMM PR雷达与阜阳雷达降水资料的对比研究   总被引:8,自引:0,他引:8  
王成刚  葛文忠  魏鸣 《遥感学报》2003,7(4):332-336
选取了1998年与1999年HUBEX观测资料,将TRMM卫星上的星载降雨雷达PR与阜阳的713数字化天气雷达资料在以下3个方面做了比较:(1)强度场的分布;(2)平均反射率廓线;(3)灵敏度。分析、比较结果可知阜阳雷达在探测灵敏度和水平方向的分辨率要高于PR,但由于波束宽度、衰减和资料转化过程计算误差的原因,其远距离处的观测值与真实值有一定偏差。PR波长短,对衰减敏感,尤其是在垂直方向上经过强衰减后,订正值仍偏小。但由于探测方式的不同PR在水平方向上不存在衰减的问题,且其资料分布均匀,因此提出一种用PR资料来订正地基雷达资料的方法用以提高地基雷达探测的精确度。  相似文献   

14.
TRMM PR雷达与阜阳雷达降水资料的对比研究   总被引:1,自引:0,他引:1  
王成刚  葛文忠  魏鸣 《遥感学报》2003,7(3):332-336
选取了1998年与1999年HUBEX观测资料,将TRMM卫星上的星载降雨雷达PR与阜阳的713数字化天气雷达资料在以下3个方面做了比较:(1)强度场的分布;(2)平均反射率廓线;(3)灵敏度。分析、比较结果可知阜阳雷达在探测灵敏度和水平方向的分辨率要高于PR,但由于波束宽度、衰减和资料转化过程计算误差的原因,其远距离处的观测值与真实值有一定偏差。PR波长短,对衰减敏感,尤其是在垂直方向上经过强衰减后,订正值仍偏小。但由于探测方式的不同PR在水平方向上不存在衰减的问题,且其资料分布均匀,因此提出一种用PR  相似文献   

15.
有效监测人工水产养殖水面的分布变化对于海洋资源管理、生态环境保护、防灾减灾具有重要意义。本文以Landsat 5、SPOT 5和GF-1卫星影像为数据源,选择广东省北莉岛为研究区,使用线性光谱解混方法获取中等空间分辨率卫星影像的人工水产养殖水面面积,通过面向对象多尺度分割的方法结合支持向量机分类算法提取高空间分辨率卫星影像的人工水产养殖水面分布。研究结果表明,与单一卫星影像相比,综合多源中高空间分辨率卫星数据延长了人工水产养殖水面变化分析可追溯的时间跨度,提高了监测精度;联合光谱解混和面向对象分类方法开展人工水产养殖长时序遥感监测是可行的。近20多年来,北莉岛人工水产养殖水面的面积经历了先增加后缓慢减少的变化过程,1995—2000年平均增速为23.39 hm2/a,2000—2006年平均增速为23.95 hm2/a,2006—2019年平均减少速度为1.96 hm2/a。  相似文献   

16.
The present study describes a procedure for quantitatively analyzing satellite telemetry data to identify interspecific land use differences among four threatened crane species. The inherent inaccuracy of satellite telemetry data points, the temporal autocorrelation of those points, and the resolution of two land‐cover imagery products from the IGBP‐DISCover Global Land‐Cover Characterization Project (derived from AVHRR data) were assessed and integrated in a GIS. Satellite telemetry is a system where animals are tracked using battery‐operated transmitters and locations are calculated using triangulation from satellites. Using the variable spatial inaccuracy of the telemetry locations, each point was buffered using a radius based on the accuracy of the point, and then intersected with the land cover imagery. The research concluded that the methodology is valuable for studies of birds at a regional scale, with interspecific differences clearly evident, but that diurnal and nocturnal differences were not discernable due to the coarse resolution of both satellite telemetry and land‐cover data.  相似文献   

17.
高分辨率卫星影像已经成为获取地理信息的重要数据源,而其定向是一项关键技术。本文利用单侧不同数量及分布的控制点对SPOT5 HRG影像进行了定向试验,探讨了在单侧控制条件下SPOT5 HRG影像的定向精度情况,为地面控制点获取较困难地区的影像定向提供了一条参考途径。  相似文献   

18.
The spatial differentiation of socioeconomic classes in a city can deliver insight into the nexus of urban development and the environment. The purpose of this paper is to identify poor and rich regions in large cities according to the predominant physical characteristics of the regions. Meaningful spatial information from urban systems can be derived using remote sensing and GIS tools, especially in large difficult-to-manage cities where the dynamics of development results in rapid changes to urban patterns. We use here very high resolution imagery data for the identification of homogeneous socioeconomic zones in a city. We formulate the categorization task as a GIS analysis of an image classified with conventional techniques. Experiments are conducted using a QuickBird image of a study area in Lima, Peru. We provide accuracy assessment of results compared to ground truth data. Results show an approximated allocation of socioeconomic zones within Lima. The methodology described could also be applied to other urban centers, particularly large cities of Latin America, which have characteristics similar to those of the study area.  相似文献   

19.
利用雷达干涉数据进行城市不透水层百分比估算   总被引:2,自引:0,他引:2  
人工不透水层是城市地区的重要特征.作为城市生态环境的关键指数,不透水层百分比(Impervious Surfaces Percentage, ISP)常用于城市水文过程模拟、水质面源污染及城市专题制图等研究中.本文利用ERS-1/2 重复轨道雷达干涉数据,采用分类与回归树(CART)算法探究了雷达遥感在城市ISP估算中的可行性和潜力,并与SPOT5 HRG光学遥感图像的估算结果进行了分析比较.香港九龙港岛实验区的初步研究结果表明,雷达干涉数据在城市不透水层研究中具有一定的应用潜力,特别是裸土和稀疏植被的ISP估算结果要好于光学遥感,这主要得益于雷达干涉数据(特别是长时间相干图像)在人工建筑物和裸土或稀疏植被之间具有很强的区分能力,另外,雷达干涉数据和光学遥感数据间的融合能够提高ISP估算精度.  相似文献   

20.
The aim of the study was to elaborate a methodology for forest mapping based on high resolution satellite data, relevant for reporting on forest cover and spatial pattern changes in Europe. The Carpathians were selected as a case study area and mapped using 24 Landsat scenes, processed independently with a supervised approach combining image segmentation, knowledge-based rules to extract a training set and the maximum likelihood decision rule. Validation was done with available very high resolution imagery. Overall accuracies per scene ranged from 93 to 96%. The labelling disagreement in overlapping areas of adjacent scenes was 6.8% on average.  相似文献   

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