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3-D Shoreline Extraction from IKONOS Satellite Imagery 总被引：1，自引：0，他引：1
Shorelines are recognized as unique features on Earth. They have valuable properties for a diverse user community. At present, photogrammetry is the most popular technique used to capture a shoreline. With improved resolution and accuracy, commercial high-resolution satellite imagery is demonstrating a great potential in the photogrammetry application domain. One example is the utilization of IKONOS satellite imagery in shoreline extraction. IKONOS panchromatic imagery has a resolution of approximately one meter as well as the capabilities of stereo imaging. This article presents the results of an experiment in which we attempted to improve IKONOS Rational Functions (RF) for a better ground accuracy and to employ the improved RF for 3-D shoreline extraction using 1-meter panchromatic stereo images in a Lake Erie coastal area. Two approaches were investigated. One was to rectify the ground coordinates derived from vendor-provided RF coefficients using ground control points (GCPs). The other was to refine the RF coefficients using the GCPs. We compare the results from these two approaches. An assessment of the shoreline extracted from IKONOS images compared with the existing shoreline is also conducted to demonstrate the potential of the IKONOS imagery for shoreline mapping. 相似文献
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Rongxing Li Sagar Deshpande Xutong Niu Feng Zhou Kaichang Di Bo Wu 《Marine Geodesy》2013,36(3):143-159
This paper investigates the geopositioning accuracy achievable from integrating IKONOS and QuickBird satellite stereo image pairs with aerial images acquired over a region at Tampa Bay, Florida. The results showed that the accuracy is related to a few factors of imaging geometry. For example, the geopositioning accuracy of a stereo pair of IKONOS or QuickBird images can be improved by integrating a set of aerial images, even just a single aerial image or a stereo pair of aerial images. Shorelines derived from the IKONOS and QuickBird stereo images, particularly the vertical positions, are compared with the corresponding observations of water-penetrating LiDAR and water gauge stations and proved that differences are within the limit of the geopositioning uncertainty of the satellite images. 相似文献
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Island shoreline mapping based on field measurements by collecting visually discernible features is costly and even unrealistic to be implemented in practice because of the nonuniqueness, fuzziness, and ambiguity of shoreline features. The MHHW (the mean higher high water) shoreline, i.e., the intersection of the coastal profile with the MHHW, is recommended to be chosen as a significant shoreline indicator of an island. An approach for mapping the MHHW shoreline using the aerial/satellite stereo images is proposed. In the proposed procedure, first, the height difference between the instantaneous shoreline and the MHHW shoreline is calculated by the ocean tide model; then the orthometric/normal height of the instantaneous shoreline is determined from the stereo images; last, the instantaneous shoreline is used as an intermediate for determination of the height of the MHHW shoreline. The proposed procedure is applied to the MiaoZiHu Island located in the East China Sea. Preliminary experimental result shows that in ideal cases, the horizontal positional accuracy of the extracted shoreline can reach 0.2 m from aerial images of 0.1 m resolution. 相似文献
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陆地卫星自20世纪70年代初发射以来即用于岸线动态的研究，SPOT卫星资料的利用更增加了该类研究的精度， Radarsat影像由于其对水陆界线的敏感而被用于海岸带制图；航空摄影影像由于其比例尺大，空间分辦率高，成像时间可以人为控制，便于低潮时海滩大比例尺制图等优点而被广为利用。自20世纪三四十年代以来，已经有了许多海滩的航空照片，据此可以获得较长系列的海滩变化信息。 相似文献
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The shoreline is one of the most important features on earth's surface. It is valuable to a diverse user community. But the dynamic nature of the shoreline makes it difficult to be represented in a naturally dynamic style and to be utilized in applications. The officially used shoreline, for example in nautical charts, is the so-called tide-coordinated shoreline. It is also the shoreline that makes the computation of shoreline changes and associated environmental changes meaningful. Mapping of the tide-coordinated shoreline has been very costly. On the other hand, instantaneous shorelines extracted from different data sources may be available. Also, high-resolution satellite and airborne imagery have the capacity of stereo imaging and can be used to extract instantaneous shorelines at a high accuracy and low cost. This article proposes an approach to derivation of digital tidecoordinated shorelines from (a) those instantaneous shorelines and (b) digital coastal surface models and a digital water surface model. Some preliminary study results, analysis, and the potential of the approach are discussed. 相似文献
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Digital Tide-Coordinated Shoreline 总被引：4，自引：0，他引：4
The shoreline is one of the most important features on earth's surface. It is valuable to a diverse user community. But the dynamic nature of the shoreline makes it difficult to be represented in a naturally dynamic style and to be utilized in applications. The officially used shoreline, for example in nautical charts, is the so-called tide-coordinated shoreline. It is also the shoreline that makes the computation of shoreline changes and associated environmental changes meaningful. Mapping of the tide-coordinated shoreline has been very costly. On the other hand, instantaneous shorelines extracted from different data sources may be available. Also, high-resolution satellite and airborne imagery have the capacity of stereo imaging and can be used to extract instantaneous shorelines at a high accuracy and low cost. This article proposes an approach to derivation of digital tidecoordinated shorelines from (a) those instantaneous shorelines and (b) digital coastal surface models and a digital water surface model. Some preliminary study results, analysis, and the potential of the approach are discussed. 相似文献
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文章针对中低分辨率遥感影像难以提取海岸线中小尺度变化的实际问题,以渤海湾为例,利用2010—2020年SPOT5、GF-1/6、ZY-3等高分辨率遥感影像,采用数字海岸线分析和分形维数方法获取渤海湾海岸线位置变迁速率和复杂度变化过程;针对目前渤海湾海岸线变迁分析研究多基于中低分辨率遥感影像的问题,结合同时期的Landsat影像,分析遥感影像空间分辨率对渤海湾海岸线变迁速率和分形维数的影响。研究结果表明,遥感影像空间分辨率差异对分形维数的影响较小,但对不同类型的岸线变迁速率影响显著;渤海湾海岸线在2010—2020年的变化呈现出由剧烈过渡至相对稳定的状态,伴随着海岸线位置的变化,岸线的分形维数呈现出先上升再至平稳的趋势。相关研究成果能够为渤海湾地区海洋资源利用优化、海岸线及滩涂湿地等自然资源保护提供数据支持。 相似文献
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图像融合在遥感中的应用 总被引：4，自引：0，他引：4
介绍了关于低分辨率的多光谱图像与高分辨率的全色图像相融合的一些方法。图像融合的目的是为了获取高分辨率的多光谱图像,它既包含了多光谱信息又具有全色图像的高空间分辨率特点。图像融合在遥感中的主要目的在于尽量保持图像的光谱信息．以便用于土地覆盖分类等领域,这一点与其在军事应用和计算机辅助设计领域有所不同。阐述了如何在不使用高分辨率的全色图像情况下进行融合的方法,由于同时获取的多光谱图像之间存在亚像元级的偏移现象,将位移量作为附加信息来有效提高采样频率,以此获取高空间分辨率信息。最后选取了SPOT卫星的多光谱图像作为例子．对文中所阐述的算法进行了试验,并对试验结果作了比较分析。 相似文献
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提出了一种改进的Curvelet变换的融合算法,以IKONOS影像为样本数据,融合过程中将原全色波段与多光谱影像中未参与HIS分解的波段进行加权组合,形成新全色分量,再将此分量与明度分量分别进行第二代Curvelet变换,以形成新明度分量,HIS逆变换后形成融合影像。并与改进的HIS变换融合、传统的HIS变换与Curvelet变换结合的融合算法相比较,结果表明,改进的方法能增加融合影像的信息量,降低光谱扭曲度,提高融合影像与原多光谱影像的相似度。 相似文献
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A. Vela V. Pasqualini V. Leoni A. Djelouli H. Langar G. Pergent C. Pergent-Martini L. Ferrat M. Ridha H. Djabou 《Estuarine, Coastal and Shelf Science》2008,79(4):591-598
Mapping marine biocenoses is an efficient method for providing useful data for the management and conservation of Mediterranean lagoons. Fused images from two satellites, SPOT 5 and IKONOS, were tested as management tools for identifying specific ecosystems in the El Bibane lagoon, situated in southern Tunisia near the Libyan border. The objectives of this study were to provide a precise map of the entire El Bibane lagoon using fused images from SPOT 5 and to compare fused images from SPOT 5 and IKONOS over a test-area. After applying a supervised classification, pixels are automatically classified in four classes: low seagrass cover, high seagrass cover, superficial mobile sediments and deep mobile sediments. The maps of the lagoon revealed and confirmed an extremely wide distribution of seagrass meadows within the lagoon (essentially Cymodocea nodosa; 19 546 ha) and a large area of mobile sediments more or less parallel to the shore (3 697 ha). A direct comparison of overall accuracy between SPOT 5 over the entire area, SPOT 5 over the test-area and IKONOS over the test-area revealed that these tools provided accurate mapping of the lagoon environment (83.25%, 85.91% and 73.41% accuracy, respectively). The SPOT 5 images provided greater overall accuracy than the IKONOS image, but did not take into account the heterogeneous spatial structure of the seagrasses and sediments present in the lagoon environment. Although IKONOS imagery provided lower overall accuracy than SPOT 5, it proved a very useful tool for the mapping of heterogeneous structures as it enabled the patchiness of formations to be better taken into account. The use of SPOT 5 and IKONOS fused images appears to be very promising for completing the mapping of lagoons in other regions and countries of the Mediterranean Sea. 相似文献
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V. G. Bondur V. A. Dulov A. B. Murynin Yu. Yu. Yurovsky 《Izvestiya Atmospheric and Oceanic Physics》2016,52(9):888-903
The results of studying sea-wave spectra in a wide wavelength range using high resolution (0.5–1.0 m) satellite optical imagery spectra and the results of measurements carried out from an oceanographic platform using string-wave recorders, stereo system, and drifting wave buoys are presented in this paper. The wave spectra retrieved from satellite imagery and sea-truth data have been compared. A comparison has shown the adequacy of the purposely developed retrieval methods. Power approximation indices for spatial spectra in the 0.04–5.0-m wavelength range have been found. It has been shown that the wave spectra measured experimentally by satellite-based and in-situ methods best approximate the Toba spectrum. 相似文献
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Jonathan B. Thayn 《Marine Geodesy》2020,43(5):493-508
AbstractSmall stands of mangrove trees are difficult to detect and monitor using satellite remote sensing because the width of the narrow strips of vegetation are typically much smaller than the spatial resolution of the imagery. Every mangrove pixel also contains water and bare soil reflectance. Linear spectral unmixing, which estimates the fractional presence of specific land cover types per pixel, was performed on Landsat 8 imagery to detect mangroves on the eastern shoreline of the Bay of La Paz on the Baja California Peninsula of Mexico. Low-altitude aerial imagery collected from a DJI Mavic Pro drone was used as ground-reference data in the accuracy assessment. Continuous fractional presence of mangroves was detected with 80% accuracy and 85% of mangrove area was found. Future work will use linear spectral unmixing to systematically monitor mangrove extent and health in the region relative to expected growth in tourism development. 相似文献
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Shoreline change analysis and prediction are important for integrated coastal zone management, and are conventionally performed by field and aerial surveys. This paper discusses an alternative cost-effective methodology involving satellite remote sensing images and statistics. Multi-date satellite images have been used to demarcate shoreline positions, from which shoreline change rates have been estimated using linear regression. Shoreline interpretation error, uncertainty in shoreline change rate, and cross-validation of the calculated past shorelines have been performed using the statistical methods, namely, Regression coefficient (R2) and Root Mean Square Error (RMSE). This study has been carried out along 113.5 km of coast adjoining Bay of Bengal in eastern India, over the time interval 1973 to 2003. The study area has been subdivided into seven littoral cells, and transects at uniform interval have been chosen within each cell. The past and future shoreline positions have been estimated over two time periods of short and long terms in three modes, viz., transect-wise, littoral cell-wise and regionally.The result shows that 39% of transects have uncertainties in shoreline change rate estimations, which are usually nearer to cell boundaries. On the other hand, 69% of transects exhibit lower RMSE values for the short-term period, indicating better agreement between the estimated and satellite based shoreline positions. It is also found that cells dominated by natural processes have lower RMSE, when considered for long term period, while cells affected by anthropogenic interventions show better agreement for the short-term period. However, on regional considerations, there is not much difference in the RMSE values for the two periods. Geomorphological evidence corroborates the results. The present study demonstrates that combined use of satellite imagery and statistical methods can be a reliable method for shoreline related studies. 相似文献
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1Introduction Satelliteimagerycanbecomeavaluablecompo nentinageographicinformationsystem(GIS)data baseonlyafterithasbeengeo referencedtoaground coordinatesystemwiththedesiredprojection(Mei,etal.,2001;Wang,etal.,2002).Allimagesre ceivedatagroundreceivingst… 相似文献
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利用海岸线的海洋遥感图像控制点(GCP)自动匹配法 总被引：5，自引：2，他引：3
研究一种利用海岸线自动确定海上地面控制点(GCP)的方法.借助边缘检测技术提取海岸线,将海岸线的点全部作为控制点的备选集合,利用相关松弛法寻找同名点,建立一种可靠判别机制来保证海岸线上GCP的正确性,通过平均法和插值法求取海上GCP的值.利用本方法可以方便地得到分布密集的GCP值,其中海上GCP值具有子像元精度.同时研究了一种新的几何变换方法,即用插值法直接求取需校正图像的几何变换坐标,随着插值密度的增加,求得海上GCP值的点就越多,最后使所有点的坐标值通过插值方法计算得到,代替二元n次方程组进行空间坐标变换,使遥感图像的几何配准误差在某种程度上达到0,利用该方法对海洋遥感资料进行几何配准,可以提高配准的精度和节省机时,为遥感资料的动态监测和数据库建设创造了有利条件. 相似文献
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Semi-automated procedures for shoreline extraction using single RADARSAT-1 SAR image 总被引：1，自引：0，他引：1
Coastline identification is important for surveying and mapping reasons. Coastline serves as the basic point of reference and is used on nautical charts for navigation purposes. Its delineation has become crucial and more important in the wake of the many recent earthquakes and tsunamis resulting in complete change and redraw of some shorelines. In a tropical country like Malaysia, presence of cloud cover hinders the application of optical remote sensing data. In this study a semi-automated technique and procedures are presented for shoreline delineation from RADARSAT-1 image. A scene of RADARSAT-1 satellite image was processed using enhanced filtering technique to identify and extract the shoreline coast of Kuala Terengganu, Malaysia. RADSARSAT image has many advantages over the optical data because of its ability to penetrate cloud cover and its night sensing capabilities. At first, speckles were removed from the image by using Lee sigma filter which was used to reduce random noise and to enhance the image and discriminate the boundary between land and water. The results showed an accurate and improved extraction and delineation of the entire coastline of Kuala Terrenganu. The study demonstrated the reliability of the image averaging filter in reducing random noise over the sea surface especially near the shoreline. It enhanced land-water boundary differentiation, enabling better delineation of the shoreline. Overall, the developed techniques showed the potential of radar imagery for accurate shoreline mapping and will be useful for monitoring shoreline changes during high and low tides as well as shoreline erosion in a tropical country like Malaysia. 相似文献