共查询到20条相似文献，搜索用时 31 毫秒
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Testing satellite and ground thermal imaging of low-temperature fumarolic fields: The dormant Nisyros Volcano (Greece) 总被引：1，自引：0，他引：1
E. Lagios S. Vassilopoulou V. Sakkas V. Dietrich B.N. Damiata A. Ganas 《ISPRS Journal of Photogrammetry and Remote Sensing》2007,62(6):447-460
The Nisyros Volcano (Greece) was monitored by satellite and ground thermal imaging during the period 2000–2002. Three night-scheduled Landsat-7 ETM+ thermal (band 6) images of Nisyros Island were processed to obtain land surface temperature. Ground temperature data were also collected during one of the satellite overpasses. Processed results involving orthorectification and 3-D atmospheric correction clearly show the existence of a thermal anomaly inside the Nisyros Caldera. This anomaly is associated mainly with the largest hydrothermal craters and has land surface temperatures 5–10 °C warmer than its surroundings. The ground temperature generally increased by about 4 °C inside the main crater over the period 2000–2002. Ground thermal images of the hydrothermal Stephanos Crater were also collected in 2002 using a portable thermal infrared camera. These images were calibrated to ground temperature data and orthorectified. A difference of about 0–2 °C was observed between the ground thermal images and the ground temperature data. The overall study demonstrates that satellite remote sensing of low-temperature fumarolic fields within calderas can provide a reliable long-term monitoring tool of dormant volcanoes that have the potential to reactivate. Similarly, a portable thermo-imager can easily be deployed for real-time monitoring using telemetric data transfer. The operational costs for both systems are relatively low for an early warning system. 相似文献
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结合国家1∶50 000数据库更新工程中影像正射纠正的需要,对于我国较多山区地形复杂、GPS控制点的测量困难地区,利用1∶50 000 DLG中的道路和1∶50 000 DRG数据作为控制资料,通过对控制点选取方式和纠正方法的研究,实现对SPOT 5影像的正射纠正,避免了外业控制点的测量。经过试验,分析其正射纠正精度,... 相似文献
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Landsat (TM) imagery studies combined with photogeology, heliborne EM-radiometric interpretations and field data provided the fracture pattern in the eastern Chalkidiki peninsula, northern Greece. Processing of the respective data revealed the following four main directions of lineaments trending 070°–080°, 120°–130°, N-S and E-W. This fracture pattern is persistent in all geological units including the Tertiary basins and may represent reactivated older or even Tertiary fractures superimposed on all units. The control and the distribution of the major mineralization such as Pb---Zn (Au---Ag) massive sulphides, Mn (Fe) oxides, and porphyry Cu (Au) are of similar orientation to the deduced fracture pattern.These findings support the remote sensing is an important mineral exploration tool which can become quite effective when combined with ore deposit type, geochemical and geophysical data in partly explored areas. 相似文献
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浅谈QuickBird遥感卫星影像几何精校正 总被引：2，自引：0，他引：2
QuickBird卫星影像是目前商用高精度遥感图像，因其空间分辨率较高，数据产品格式复杂，目前在实际应用中对其几何精校正（包括正射校正）还存在许多问题。本文就近年来承担有关项目——高精度遥感图像在西藏、云南、四川等地区机场建设工程应用的基础上，探讨了QuickBird卫星影像的几何精校正方法、原理以及高精度正射遥感影像地图制图工艺的关键性技术问题。 相似文献
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邓盛满 《测绘与空间地理信息》2014,(3):204-206
采用基于RPC模型进行ZY-3影像正射纠正处理时,当使用全局布点控制方案时控制点增加到12个以上后,对整景影像的纠正精度影响不明显,且由于选取多个高精度的控制点非常困难,而有时控制点的增加并不一定能带来精度的提高。本文通过采用几种不同的控制点布设方案对同一景ZY-3影像进行正射纠正,并对几种方案的纠正成果进行了精度比较和分析,从而进一步证实了选择合适的控制点布设方案和控制点数量大大提高ZY-3影像的纠正质量和纠正效率。 相似文献
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This paper presents the main results of a comprehensive ADS40 performance analysis conducted at the Vaihingen/Enz test field. As such it represents one example of an independent in-flight performance study for one of the new and commercially operational digital airborne camera systems. Based on a large number of well coordinated and defined object points, which served as independent check points, the absolute geometric accuracy of the ADS40 from true operational data has been verified. Empirical analysis of data from flying heights ranging from 1500 m to 4000 m proved the ADS40 geometric accuracy to be in the range of 1–2 μm at image scale for horizontal coordinates and 0.03–0.05‰ of the flying height for vertical components. This is fully within specification for airborne imaging. 相似文献
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一种高精度的干涉雷达复数影像配准方法 总被引：2，自引：0，他引：2
在总结现有算法的基础上,提出了基于相干系数、Harris特征点、小波金字塔及TIN三角微分纠正技术的单视复数雷达图像的配准流程。通过ERS 1/2的实验表明,提高了配准的精度和效率,特别是保证了在没有精确轨道甚至没有轨道参数的情况下也能获得很高的配准精度,计算正确的干涉相位图。在重采样过程中采用的三角联网策略,进一步使匹配点的局部拟合误差得到有效控制,得到配准精度更高的复图像对。在CPU 3.06GHz计算机上,43 s内完成5000像素×1000像素的主辅图像的配准,平均相干系数为0.719855。 相似文献
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Akira Hirano Roy Welch Harold Lang 《ISPRS Journal of Photogrammetry and Remote Sensing》2003,57(5-6):356
The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on-board the National Aeronautics and Space Administration's (NASA's) Terra spacecraft provides along-track digital stereo image data at 15-m resolution. As part of ASTER digital elevation model (DEM) accuracy evaluation efforts by the US/Japan ASTER Science Team, stereo image data for four study sites around the world have been employed to validate prelaunch estimates of heighting accuracy. Automated stereocorrelation procedures were implemented using the Desktop Mapping System (DMS) software on a personal computer to derive DEMs with 30- to 150-m postings. Results indicate that a root-mean-square error (RMSE) in elevation between ±7 and ±15 m can be achieved with ASTER stereo image data of good quality. An evaluation of an ASTER DEM data product produced at the US Geological Survey (USGS) EROS Data Center (EDC) yielded an RMSE of ±8.6 m. Overall, the ability to extract elevations from ASTER stereopairs using stereocorrelation techniques meets expectations. 相似文献
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Maria Antonia Brovelli Mattia Crespi Francesca Fratarcangeli Francesca Giannone Eugenio Realini 《ISPRS Journal of Photogrammetry and Remote Sensing》2008,63(4):427-440
Interest in high-resolution satellite imagery (HRSI) is spreading in several application fields, at both scientific and commercial levels. Fundamental and critical goals for the geometric use of this kind of imagery are their orientation and orthorectification, processes able to georeference the imagery and correct the geometric deformations they undergo during acquisition. In order to exploit the actual potentialities of orthorectified imagery in Geomatics applications, the definition of a methodology to assess the spatial accuracy achievable from oriented imagery is a crucial topic.In this paper we want to propose a new method for accuracy assessment based on the Leave-One-Out Cross-Validation (LOOCV), a model validation method already applied in different fields such as machine learning, bioinformatics and generally in any other field requiring an evaluation of the performance of a learning algorithm (e.g. in geostatistics), but never applied to HRSI orientation accuracy assessment.The proposed method exhibits interesting features which are able to overcome the most remarkable drawbacks involved by the commonly used method (Hold-Out Validation — HOV), based on the partitioning of the known ground points in two sets: the first is used in the orientation–orthorectification model (GCPs — Ground Control Points) and the second is used to validate the model itself (CPs — Check Points). In fact the HOV is generally not reliable and it is not applicable when a low number of ground points is available.To test the proposed method we implemented a new routine that performs the LOOCV in the software SISAR, developed by the Geodesy and Geomatics Team at the Sapienza University of Rome to perform the rigorous orientation of HRSI; this routine was tested on some EROS-A and QuickBird images. Moreover, these images were also oriented using the world recognized commercial software OrthoEngine v. 10 (included in the Geomatica suite by PCI), manually performing the LOOCV since only the HOV is implemented.The software comparison guaranteed about the overall correctness and good performances of the SISAR model, whereas the results showed the good features of the LOOCV method. 相似文献
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以实际应用为背景,比较了多项式模型、直接线性变换、基于RPC文件的有理数纠正、基于GCPs的有理数纠正、局部区域纠正、双次纠正6种纠正方法,说明QuickBird预正射产品的纠正精度、算法特点.实验表明采用基于GCPs的有理数纠正,在任意多边形研究区能获得相对较高的纠正精度,具备实际应用的可行性和实用性. 相似文献
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基于GCP库的星载SAR图像自动精校正 总被引：1，自引：0，他引：1
近年来,合成孔径雷达(SAR)技术已取得巨大进步,人们也越来越重视其潜在的应用前景。但是,雷达侧视成像性质和地形起伏的影响导致SAR图像的几何畸变非常复杂,大大影响了SAR图像的应用。几何精校正是SAR图像广泛应用的前提,但是校正过程中需要大量地面控制点(GCPs),以往的人工选点方法费时费力。本文提出了一种基于控制点自动匹配的控制点选点方法,用以提高点位精度和工作效率。该方法包括纠正区域GCP库的建立和GCP图像片的自动匹配。试验结果表明,该方法具有较好的应用价值。 相似文献
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Peter Gege Jochen Fries Peter Haschberger Paul Schtz Horst Schwarzer Peter Strobl Birgit Suhr Gerd Ulbrich Willem Jan Vreeling 《ISPRS Journal of Photogrammetry and Remote Sensing》2009,64(4):387-397
A new facility designed to perform calibration measurements of airborne imaging spectrometers was established at the German Aerospace Center (DLR) in Oberpfaffenhofen. This Calibration Home Base (CHB) is optimized to characterize radiometrically, spectrally, and geometrically the APEX (Airborne Prism Experiment) imaging spectrometer, which is currently being developed under the authority of the European Space Agency (ESA). It however can be used for other optical sensors as well. Computer control of major laboratory equipment allows automation of time consuming measurements. In APEX configuration (wavelength range: 380 to 2500 nm, instantaneous field of view: 0.48 mrad, field of view: ±14) spectral measurements can be performed to a wavelength uncertainty of ±0.15 nm, geometric measurements at increments of 0.0017 mrad across track and 0.0076 mrad along track, and radiometric measurements to an uncertainty of ±3% relative to national standard. The CHB can be adapted to similar sensors (including those with thermal infrared detectors) by exchanging the monochromator’s lamp, the gratings and the filters, and by adjusting the distance between the sensor and folding mirror. 相似文献
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卫星影像可以低成本、高频率地提供地物光谱特性观测信息,而激光点云可以提供精细的几何结构,两类数据的融合可以实现优势互补,进一步提高地物分类和信息提取的精度和自动化程度。实现亚像素级精度的几何配准是实现两类数据融合的前提,提出了一种基于线元素距离变换模型的快速配准方法。该方法以点云为控制源,将点云中的建筑物边缘等典型线元素通过卫星影像的初始有理多项式系数(rational polynomial coefficient, RPC)投影到像方空间,与卫星影像中的线元素进行迭代最近点配准,从而通过RPC参数精校正的方式实现几何配准。采用距离变换模型作为迭代最近点搜索的查找表,提高了运算效率;采用最新的渐进式鲁棒求解策略,能在噪声极多的情况下保证配准的鲁棒性。采用GeoEye-2、高分七号、WorldView-3等卫星影像与激光点云进行了配准实验,并分别通过人工精确量测的外业控制点和作业员内业刺的控制点作为检查,证明所提方法能在3种影像上达到0.4～0.7 m的配准精度,显著优于将点云映射为二维图像然后通过多模态匹配进行配准的策略。 相似文献
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利用轨道参数修正的无控制点星载SAR图像几何校正方法 总被引：1，自引：1，他引：0
使用距离多普勒模型进行SAR图像几何校正时,卫星轨道误差、系统成像参数误差和DEM高程的误差会影响几何校正精度。本文提出了一种基于轨道参数修正的星载SAR图像几何校正方法。首先利用多项式对卫星轨道进行参数化,然后使用模拟SAR图像与真实SAR图像进行匹配得到控制点来修正轨道参数,最后利用修正后的参数进行几何精校正,从而提高几何校正精度。该方法无需地面控制点,适用于不易于人工测量获取地面控制点地区的SAR图像几何校正,与基于模拟SAR图像匹配并使用多项式改正的几何校正方法相比,本文方法具有更高的精度。使用Radarsat-2图像进行试验,并使用地面实测GPS控制点验证了本方法的有效性。 相似文献
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Rangaswamy Madugundu Vyjayanthi Nizalapur Chandra Shekhar Jha 《International Journal of Applied Earth Observation and Geoinformation》2008,10(2):211-1
This study demonstrates the potentials of IRS P6 LISS-IV high-resolution multispectral sensor (IGFOV 6 m)-based estimation of biomass in the deciduous forests in the Western Ghats of Karnataka, India. Regression equations describing the relationship between IRS P6 LISS-IV data-based vegetation index (NDVI) and field measured leaf area index (ELAI) and estimated above-ground biomass (EAGB) were derived. Remote sensing (RS) data-based leaf area index (PLAI) image is generated using regression equation based on NDVI and ELAI (r2 = 0.68, p ≤ 0.05). RS-based above-ground biomass (PAGB) image was generated based on regression equation developed between PLAI and EAGB (r2 = 0.63, p ≤ 0.05). The mean value of estimated above-ground biomass and RS-based above-ground biomass in the study area are 280(±72.5) and 297.6(±55.2) Mg ha−1, respectively. The regression models generated in the study between NDVI and LAI; LAI and biomass can also help in generating spatial biomass map using RS data alone. LISS-IV-based estimation of biophysical parameters can also be used for the validation of various coarse resolution satellite products derived from the ground-based measurements alone. 相似文献
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以PixelGrid系统为例,基于集群式系统进行高精度自动空中三角测量、DEM自动匹配与正射影像快速纠正试验,并利用控制点对产品精度进行了检验,同时统计分析了集群式系统的生产效率。 相似文献
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Sabine Thiemann Helmut Schiller 《International Journal of Applied Earth Observation and Geoinformation》2003,4(4):339-349
The spatial and temporal variability of the bulk temperature gives important insights into biological and hydrodynamic processes. However, standard algorithms for satellite data only provide information of the surface temperature. The comparison of current and new split-window coefficients applied on NOAA-14/AVHRR brightness temperatures of Lake Constance showed that a regional adaption was most promising. To derive the bulk temperature information, a priori progression from a weather station was included into the AVHRR analysis. Among the weather is data, the mean temperature of the three preceding days and the day of the year were the most relevant additional information. By a multiple regression approach the bulk temperature in the upper 4 m of Lake Constance could be determined with an accuracy of ±1.20 °C. The training of a neural network improved the determination of the bulk temperature to ±1.04 °C.An extended field campaign demonstrated that the algorithm is also applicable to other sensors with the same spectral band settings (in this case NOAA-16/AVHRR) with an acceptable error and that it is equally accurate over the entire lake. 相似文献