基于亮度相关矩的MODIS和SPOT影像融合研究   总被引：4，自引：0，他引：4  

陈少辉  张秋文  王乘  周建中 《遥感学报》2006,10(1):90-96

针对MODIS影像空间分辨率较低的问题，提出了一种基于亮度相关矩的多分辨率图像融合方法。该方法首先对SPOT影像进行小波分解，将MODIS影像构成的RGB颜色系统变换到IHS颜色系统；然后，根据强度分量和SPOT影像低频分量的均值和方差来定义图像亮度相关矩；最后，IHS逆变换和小波逆变换得到包含更多信息和有效特征的融合图像。试验结果证明该方法得到的融合图像在保留地物光谱信息和提高空间分辨率上都具有很好的效果。  相似文献   

Quantitative assessment of remotely sensed global surface models using various land classes produced from Landsat data in Istanbul     

Naci Yastikli  Umut G. Sefercik  Fatih Esirtgen 《中国地理科学(英文版)》2014,24(3):307-316

Digital elevation model(DEM) is the most popular product for three-dimensional(3D) digital representation of bare Earth surface and can be produced by many techniques with different characteristics and ground sampling distances(GSD). Space-borne optical and synthetic aperture radar(SAR) imaging are two of the most preferred and modern techniques for DEM generation. Using them, global DEMs that cover almost entire Earth are produced with low cost and time saving processing. In this study, we aimed to assess the Satellite pour l'observation de la Terre-5(SPOT-5), High Resolution Stereoscopic(HRS), the Advanced Space-borne Thermal Emission and Reflection Radiometer(ASTER), and the Shuttle Radar Topography Mission(SRTM) C-band global DEMs, produced with space-borne optical and SAR imaging. For the assessment, a reference DEM derived from 1∶1000 scaled digital photogrammetric maps was used. The study is performed in 100 km2 study area in Istanbul including various land classes such as open land, forest, built-up land, scrub and rough terrain obtained from Landsat data. The analyses were realized considering three vertical accuracy types as fundamental, supplemental, and consolidated, defined by national digital elevation program(NDEP) of USA. The results showed that, vertical accuracy of SRTM C-band DEM is better than optical models in all three accuracy types despite having the largest grid spacing. The result of SPOT-5 HRS DEM is very close by SRTM and superior in comparison with ASTER models.  相似文献   

Semi-supervised support vector regression model for remote sensing water quality retrieving   总被引：1，自引：0，他引：1  

Xili Wang  Li Fu  Lei Ma 《中国地理科学(英文版)》2011,21(1):57-64

This paper proposed a semi-supervised regression model with co-training algorithm based on support vector machine, which was used for retrieving water quality variables from SPOT5 remote sensing data. The model consisted of two support vector regressors (SVRs). Nonlinear relationship between water quality variables and SPOT5 spectrum was described by the two SVRs, and semi-supervised co-training algorithm for the SVRs was established. The model was used for retrieving concentrations of four representative pollution indicators—permanganate index (CODmn), ammonia nitrogen (NH₃-N), chemical oxygen demand (COD) and dissolved oxygen (DO) of the Weihe River in Shaanxi Province, China. The spatial distribution map for those variables over a part of the Weihe River was also produced. SVR can be used to implement any nonlinear mapping readily, and semi-supervised learning can make use of both labeled and unlabeled samples. By integrating the two SVRs and using semi-supervised learning, we provide an operational method when paired samples are limited. The results show that it is much better than the multiple statistical regression method, and can provide the whole water pollution conditions for management fast and can be extended to hyperspectral remote sensing applications.  相似文献   

Assessment of SPOT 5 and QuickBird remotely sensed imagery for mapping tree cover in savannas     

G.S. Boggs 《International Journal of Applied Earth Observation and Geoinformation》2010

The relative abundance and distribution of trees in savannas has important implications for ecosystem function. High spatial resolution satellite sensors, including QuickBird and IKONOS, have been successfully used to map tree cover patterns in savannas. SPOT 5, with a 2.5 m panchromatic band and 10 m multispectral bands, represents a relatively coarse resolution sensor within this context, but has the advantage of being relatively inexpensive and more widely available. This study evaluates the performance of NDVI threshold and object based image analysis techniques for mapping tree canopies from QuickBird and SPOT 5 imagery in two savanna systems in southern Africa. High thematic mapping accuracies were obtained with the QuickBird imagery, independent of mapping technique. Geometric properties of the mapping indicated that the NDVI threshold produced smaller patch sizes, but that overall patch size distributions were similar. Tree canopy mapping using SPOT 5 imagery and an NDVI threshold approach performed poorly, however acceptable thematic accuracies were obtained from the object based image analysis. Although patch sizes were generally larger than those mapped from the QuickBird image data, patch size distributions mapped with object based image analysis of SPOT 5 have a similar form to the QuickBird mapping. This indicates that SPOT 5 imagery is suitable for regional studies of tree canopy cover patterns.  相似文献   

地物波谱数据辅助的SPOT影像模拟真彩色方法研究   总被引：1，自引：0，他引：1  

朱长明  骆剑承  沈占锋  程熙  胡晓东 《测绘学报》2010,39(2):169-174

提出一种新的高分辨率遥感影像真彩色模拟方法。该方法从遥感成像光谱角度,依据地物波谱特性,采用光谱角匹配模型(SAM),首先计算出地物在绿(G)、红(R)、近红外(NIR)以及短波红外(SWIR)波段的整体和局部波谱向量角;然后根据角度距离构建最小距离隶属函数,查找对应地物波谱库中最为相似的地物波谱;最后对此条地物波谱曲线积分计算出该像素点在蓝波段的反射率。实验表明,该方法模拟出的SPOT真彩色影像在视觉效果和空间信息上优于传统的方法。  相似文献   

利用SPOT5 HRS/HRG立体影像提取DEM方法的探讨     

石江南  张峰 《四川测绘》2010,(6):263-265,286

本文结合生产实践讨论了利用SPOT5 HRS/HRG立体影像提取DEM的技术和方法,通过试验证明了SPOT5 HRS/HRG立体影像在提取高山峡谷地区DEM的优势,并对提取出的DEM成果精度进行了分析。  相似文献   

面向对象方法在SPOT5遥感图像分类中的应用--以北京市海淀区为例   总被引：32，自引：2，他引：30  

曹宝  秦其明  马海建  邱云峰 《地理与地理信息科学》2006,22(2):46-50

SPOT5图像的空间分辨率高,局部异质性较大,采用基于像元的传统方法分类精度低,难以满足实际应用的需要。以北京市海淀区SPOT5图像为例,应用面向对象方法对其进行分类试验,并将该方法与传统基于像元方法的分类结果进行对比分析。结果表明:利用面向对象方法对SPOT5遥感图像进行分类,不仅使分类结果具有丰富的语义信息,有效抑制“椒盐现象”的发生,还可以显著提高分类精度。  相似文献   

肾综合征出血热疫情与NDVI的时间关系——以内蒙古自治区大杨树镇为例          下载免费PDF全文

闫磊  黄华国  张文义  王剑波  任玉环  方立群  黄晓霞  曹务春  闫守邕  王世文 《遥感学报》2009,13(5):880-893

利用月度肾综合征出血热发病人数和长时序月度NDVI值的相互关系, 对肾综合征出血热的发病趋势及发病人数进行预测。研究区大杨树镇2001—2005年共有144例完整的HFRS病人资料, 以及同期详细的宿主动物捕获数据。基于Landsat TM影像以及Google earth 影像, 大杨树地区土地利用分为4种类型, 山地、林地、农田以及居民点。各类土地利用类型的NDVI数据由SPOT-4 卫星的 VGT-S10数据集(10d最大化合成的NDVI数据)提供。对HFRS病例与NDVI之间的关系进行图解分析、相关分析和回归分析。研究表明, NDVI的峰值多出现于8月, 而HFRS发病人数的峰值多出现在11月。前朔3个月的农田NDVI值与HFRS病例数之间的相关系数为0.67(P值<0.001)。农田NDVI峰值比HFRS病例的峰值提前了3个月。研究量化了NDVI与HFRS之间的关系, 为HFRS早期预警系统的建立提供了依据。  相似文献