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1.
Sea WiFS与AVHRR资料自动几何配准   总被引:3,自引:0,他引:3  
研究了一种自动几何配准的方法,来实现多时相的卫星资料和不同遥感资料之间的几 配准。利用海岸线自动选取GCP的点,借助相关松弛法录找同名点,且有判别机制来保证GCP的正确性,可以方便地得到分布密集的GCP值。同时研究了二元n次方程组和GCP数目与配维精度的关系,得到GCP数目的增加可明显提高几何配准精度。利用该方法对SeaWiFS和AVHRR资料进行了几何配准,可以提高几何配准的精度和节省机时,为遥  相似文献   

2.
针对光学和合成孔径雷达(synthetic aperture radar,SAR)影像间的几何形变和辐射差异造成的配准困难问题,提出一种基于空间几何约束和结构特征的光学影像与SAR影像自动配准方法.首先,利用分块的Harris算子在输入影像上提取分布均匀的特征点,根据有理函数模型对输入影像进行局部几何纠正,实现输入影像...  相似文献   

3.
通过对GF-2卫星影像正射校正及波段模拟配准误差试验,分析GF-2卫星正射校正方法的选择以及不同配准误差下对GF-2卫星影像自动分类结果的影响;最后介绍GF-2遥感影像在森林资源监测应用中的初步测试。研究结果表明:正射校正时,当校正精度要求控制在RMS2时,控制点数量选择范围在85~95间较为合理,且控制点数在90个时,RMS值最小;经有理函数模型与卫片模型比较后,卫片模型校正精度较高;以目视判读为主时,实践中建议使用三次卷积重采样法输出结果最好;波段模拟配准误差试验中,配准误差与各地类面积变化间存在显著的线性关系;对于森林面积监测时,配准误差应小于0.3个像元。此研究可为新型国产卫星数据在森林资源监测中的应用提供参考。  相似文献   

4.
针对多源光学卫星影像几何校正过程中同名点匹配率低、配准过程自动化差等问题,本文采用相位一致性代替原始尺度不变特征变换(scale invitation feature transform,SIFT)算法中的像素灰度值梯度对主方向和特征向量进行描述,提升特征描述的正确率;以频率域下相位分析结果为约束条件对匹配结果进行优化,抑制错误匹配同名点;同时,提出了一种基于随机采样一致性(RANSAC)的自适应选择策略,提高参数估计阶段的自动化水平;最后,实现多源光学卫星影像间的配准。多组数据实验结果表明了该方法在辐射非线性畸变多源光学卫星影像间配准中的有效性和适用性。  相似文献   

5.
针对常规SAR影像匹配方法在地形起伏较大区域无法获取理想的SAR立体影像匹配结果的问题,该文提出了一种基于模拟纠正影像的SAR立体影像匹配方法。利用观测区域粗分辨率DEM进行SAR影像模拟,进而获取几何纠正SAR影像,在几何纠正SAR影像上实现影像匹配,等效于常规基于灰度影像匹配中进行的影像粗配准工作,并且相比于常规粗配准,该等效粗配准过程能够均衡地顾及到整幅影像的像元,最终实现了地形起伏较大区域的高精度SAR立体影像匹配。采用COSMO-Skyped影像数据进行了实验,实验结果表明,匹配精度达到了3个像素左右,比常规的基于灰度影像匹配方法有较大提高,能够有效解决地形起伏较大区域SAR立体影像匹配问题。  相似文献   

6.
作为SPOT系列卫星的性能补充,Pleiades卫星具有0.5 m的高空间分辨率且最大幅宽达到了20 km。本文针对Pleiades卫星影像的特性,研究了基于Pleiades卫星影像的1∶10 000数字正射影像图的制作流程,探讨了制图过程中涉及的关键技术,并就用户关心的影像质量控制问题进行了分析。  相似文献   

7.
Panchromatic data of pixel resolution 5.8 m obtained from IRS-1C and IRS-1D satellites proved to be very useful for mapping purposes. One of the popular data product is the 70 km swath mosaic which is covered by a combination of 3 CCD line sensors, each with 4096 pixels. Each CCD-line sensor with different imaging times causes geometric problems of mosaicing three strips data together. In this paper, we propose the details of the design elements of system that caters to the need for accurate and automatic multi strip image registration without any second resampling of the data. The systematic geometric correction grid mapping is improved to facilitate accurate mosaicing by automatic image registration task that makes use of the overlap data within image strips and image registration is achieved up to sub-pixel level.  相似文献   

8.
图像配准技术是近年来发展迅速的图像处理技术之一,是图像融合、目标提取与定位、变化监测、高分辨率影像重建等处理工作不可缺少的步骤。首先给出了多源遥感影像配准的概念和基本过程,然后着重从匹配基元、转换函数、相似性测度、匹配策略4个方面对国内外现有的影像配准技术和方法进行了分析和评述,最后指出了影像配准技术所面临的主要难题和发展方向。  相似文献   

9.
图像配准技术是近年来发展迅速的图像处理技术之一,是图像融合、目标提取与定位、变化监测、高分辨率影像重建等处理工作不可缺少的步骤.首先给出了多源遥感影像配准的概念和基本过程,然后着重从匹配基元、转换函数、相似性测度、匹配策略4个方面对国内外现有的影像配准技术和方法进行了分析和评述,最后指出了影像配准技术所面临的主要难题和发展方向.  相似文献   

10.
单小军  唐娉  胡昌苗  唐亮  郑柯 《遥感学报》2014,18(2):254-266
环境与灾害监测预报小卫星星座(环境一号卫星,HJ-1A/B)自发射以来,在环境监测、灾害评估、土地资源调查等领域发挥了重要的作用。但是HJ-1A/B卫星CCD图像的2级产品(HJ-1 CCD图像)几何精度低,实际应用中需要进行几何精校正。HJ-1 CCD图像具有宽覆盖、大视场角、几何变形复杂的特点,几何精校正难度大。针对该问题,本文提出了一个以Landsat TM全球拼接图像为基准,基于Forstner算子和模板匹配的分层配准方法。该方法使用分层匹配获得的大量高精度且分布均匀的控制点构建Delaunay三角网,有效地解决了HJ-1 CCD图像的几何精校正问题。在配准技术研究的基础上,研发了HJ-1 CCD图像几何精校正系统,系统具有全球HJ-1 CCD图像的自动批量处理能力。实验结果表明,本文提出的几何精校正方法精度高,实现了环境星图像的自动批量处理。  相似文献   

11.
Sentinel-1卫星TOPS模式影像通常在几何配准的基础上,再次利用Burst重叠区域进行增强谱分集处理以实现高精度配准。几何配准主要依赖卫星轨道参数,难以进一步提高其配准精度,因此Sentinel-1影像配准的关键则是通过增强谱分集准确估计出几何配准后的残余偏移量。然而,增强谱分集易受失相干噪声等因素的影响,低相干条件下难以满足0.001像素的配准精度要求。因此本文首先针对单基线条件下的增强谱分集配准处理进行以下改进:①完善增强谱分集多视理论,采用前置多视处理,优化增强谱分集处理流程;②基于增强谱分集相位的残余偏移量等权估计升级为加权估计,改善参数估计方法;③完善距离向增强谱分集加权估计理论,实施距离向增强谱分集配准,增加增强谱分集的观测量。然后在单基线配准的基础上,针对时序影像处理提出优化方案:①根据影像干涉对组合所形成的增强谱分集冗余观测量进行多基线配准;②采用分布式目标技术提高增强谱分集干涉图相位质量。上述改进方案互相补充,不但能独立实施,而且可以联合使用。研究结果表明,以上改进方法能够在一定程度上提高配准精度。  相似文献   

12.
KOMPSAT3(阿里郎三号)卫星携带高分辨率0.7 m全色和2.8 m多光谱有效载荷,回访周期短,覆盖范围广,得到了广泛的应用。但由于受太阳辐射、大气干扰、云折射等物理因素的影响,造成波段之间在局部区域图像上发生非线性几何畸变,导致多光谱假彩色合成数据产生重叠现象,严重影响多光谱数据质量。本文针对在极端条件下产生的图像局部非线性几何畸变现象,探索国内外各种波段间配准方法,研究发现基于华浩超算平台的几何精校正算法能很好地达到波段间配准效果,消除了多光谱假彩色合成数据的影像重叠现象。  相似文献   

13.
针对遥感图像几何校正中GCP选取受人为因素影响较大、分布与数量难以确定等问题,在分析图像局部特征的基础上,结合Voronoi图,基于ENVI/IDL与ArcGISEngine一体化开发技术,研究了一种具有半自动选取和空间分析功能的GCP选取方法。实验通过一幅面积为3278.47km。的遥感图像进行几何校正,结果表明本文研究的GCP选取方法可以将工作效率提高近一倍,总RMS可降低约0.3个像素,在实际生产中具有一定的参考意义。  相似文献   

14.
The basic concepts and tools of automatic image registration are presented and the problems which exist are discussed. The paper describes work carried out at University College London on the registration of two images and on the registration of images with maps. It is shown that strategies have been developed which are applicable to different types of image and reference data and that with the tuning of well tried algorithms it is possible to achieve the required matching. The PAIRS technique for automatic registration of optical images from satellites has been implemented and tested and is now being developed for use with optical and microwave images. The ARCHANGEL system for registration of images with maps or vector data is also being implemented and initial results show considerable promise.  相似文献   

15.
Photorealistic visualization combines 3-D geometric models with their texture images to render the virtual world. This paper points out that the texture images should be radiometrically corrected to achieve a true realistic appearance. Such a correction should include not only the color adjustment among images of the same object, but also the shade variation caused by the illumination change. The objective of this study is to correct the input texture images such that their shade varies when being rendered under different illumination directions. To achieve this goal we first apply the specular-to-diffuse mechanism based on the dichromatic reflection model to remove the specular component from the texture image. The resultant diffusion-only image then undergoes a shade correction to produce a normalized shade-free texture image. In the final step, shades under any illumination are produced to achieve a true photorealistic effect. Presented in the paper are the principles and methods for such corrections, along with a performance evaluation based on the graphic and numerical results for roof texture images.  相似文献   

16.
Image registration aims at combining imagery from multiple sensors to achieve higher accuracy and derive more information than that obtained from a single sensor. The enormous increase in the volume of remotely sensed data that is being acquired by an ever-growing number of earth observation satellites mandates the development of accurate, robust, and automated registration procedures. An effective automatic image registration has to deal with four issues: registration primitives, transformation function, similarity measure, and matching strategy. This paper introduces a new approach for automatic image registration using linear features as the registration primitives. Linear features have been chosen because they can be reliably extracted from imagery with significantly different geometric and radiometric properties. The modified iterated Hough transform (MIHT), which manipulates the registration primitives and similarity measure, is used as the matching strategy for automatically deriving an estimate of the parameters involved in the transformation function as well as the correspondence between conjugate primitives. The MIHT procedure follows an optimal sequence for parameter estimation that takes into account the contribution of linear features with different orientations at various locations within the imagery towards the estimation of the transformation parameters in question. Experimental results using real data proved the feasibility and robustness of the suggested approach.  相似文献   

17.
在山区获取地面控制点比较困难,运用模拟SAR进行配准、校正,具有较大的优势。本文在分析SAR成像几何结构及ALOS PALSAR卫星轨道参数特征的基础上,运用RD定位模型对DEM的每个网格点进行雷达成像点的位置计算,模拟SAR图像,并提取当地入射角、投影角及规则化因子等;模拟出的SAR图像与真实SAR图像纹理吻合,有利于控制点的自动配准。在此基础上对ALOS PALSAR进行编码,构建基于规则化因子及入射角的地形辐射校正模型,消除面积效应及地形起伏造成的畸变问题,从结果中分析,校正后的图像明暗差异明显减少,这对雷达定量反演研究具有一定的现实意义。  相似文献   

18.
19.
In this paper the approach for automatic road extraction for an urban region using structural, spectral and geometric characteristics of roads has been presented. Roads have been extracted based on two levels: Pre-processing and road extraction methods. Initially, the image is pre-processed to improve the tolerance by reducing the clutter (that mostly represents the buildings, parking lots, vegetation regions and other open spaces). The road segments are then extracted using Texture Progressive Analysis (TPA) and Normalized cut algorithm. The TPA technique uses binary segmentation based on three levels of texture statistical evaluation to extract road segments where as, Normalized cut method for road extraction is a graph based method that generates optimal partition of road segments. The performance evaluation (quality measures) for road extraction using TPA and normalized cut method is compared. Thus the experimental result show that normalized cut method is efficient in extracting road segments in urban region from high resolution satellite image.  相似文献   

20.
数字镶嵌是一种常用的数字图像处理技术。然而,用常规的数字镶嵌技术(利用地面控制点) 镶嵌合成孔径雷达图像并不理想。因为侧视雷达图像的畸变(几何和辐值)都与射束方向距离有 关。当相邻航带图像拼接时,图像色调和几何位置偏差较大。本文解决了侧视雷达图像数字镶嵌 中的问题;详述了雷达图像辐值校正和几何校正方法的数学理论;实例证明了校正方法是有效的。 通过对侧视雷达图像进行合适的辐值校正和几何校正后,就能获得色调均匀、位置准确的镶嵌图像。  相似文献   

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