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Three-dimensional modelling from single images remains an interesting topic of investigation in the research community, even though range sensors are becoming a common alternative for the generation of 3D information. The interest in single-image-based modelling is motivated by a wide spectrum of applications such as cultural heritage, civil engineering, urban planning and even criminology. In this paper a complete new production flowline is presented for modelling based on a single image. The modelling process consists of a series of familiar steps in photogrammetry and computer vision: feature extraction, vanishing point computation, camera self-calibration, 3D reconstruction and dimensional analysis. In particular, the methodology developed for single-image-based modelling takes a scientific approach combining several proven techniques with robust estimators. Finally, in order to demonstrate its capabilities, the reported examples include several real situations applied in different contexts. 相似文献
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The geological structure exposed by paleoearthquake trenches is the key material to the right cognition of fault activity and paleoearthquake. However, paleoearthquake trenching inevitably destroys active tectonic geomorphic evidence and trench exposures are usually difficult to reserve. The conventional process of recording the delicate geological information, manually constructing photomosaics by image-editing software, is time-consuming and produces undesirable artificial distortions. Herein, we explored the process of constructing trench orthophotomosaics and the 3D image model using the Image-based Modeling technology and applied it to the Liutiaohe trench across the Tianqiaogou-Huangyangchuan Fault, Gansu Province. Based on the 3D image modeling and orthophotomosaic, we firstly constructed the control points and scale bars on cleaned trench walls and collected photos of all sections of the trench with a digital camera in the field, and then reconstructed the 3D model of the trench through the Agisoft PhotoScan, an efficient image-based modeling software, and finally yielded the 3D image model of the trench and othophotomasaics of the trench exposures. The results show that the automated workflow can produce seamless, sub-millimeter-level high-resolution photomosaics more quickly, with precision in the centimeter range, and the 3D image model is of great help to identify strata and geological structures in trenches with much lower capital and labor costs and low expertise levels compared with LiDAR, meanwhile, the 3D archive benefits the share and communication and even allows future reinterpreting the site using new insights. 相似文献
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国家1:50000数据库更新工程总体设计研究与技术创新 总被引：6，自引：2，他引：4
为了全面提高1:50000数据库的信息现势性和要素完整性,我国"十一五"期间组织实施了国家1:50000数据库更新工程.介绍该工程总体技术研究与技术创新工作,包括研究设计以地形数据全要素更新、全区域变化检测和全过程质量控制为主要特征的1:50000数据库全面更新模式,研究提出符合我国大面积快速更新实际需要的缩编更新优先、影像一体化更新为主的主体更新方法,设计研制规模化更新所需的生产技术系统,制定配套的生产技术规定,建立规模化更新生产业务体系,并在全国大规模更新生产中广泛使用.Abstract： The currency of geographic data refers to its consistency with respect to the real world, and plays a criti-cal role in geographic information service and applications. In order to improve the quality of geographic informa-tion service, State Bureau of Surveying and Mapping of China had launched a five year's national campaign to up-date 1 : 50000 topographic database. This paper outlines the master design and technical development of this na-tional updating engineering, which adopts a full coverage updating strategy characterized by all element topo-graphic data modeling, change detection in all related areas, and whole process data quality controlling. High resolution image-based updating and large-scale data generalization-based updating were developed and used as two majors updating techniques, a series of technical production specifications were made, Based on the above, a technical system for large scale updating production, mainly including image based updating software and data generalization based updating software, has been developed and equipped to a large number of production units. The new technical pro-duction system has been successfully implemented in national campaign to update 1 : 50000 topographic database. 相似文献
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Chris McGonigle Jonathan H. Grabowski Craig J. Brown Thomas C. Weber Rory Quinn 《Estuarine, Coastal and Shelf Science》2011
Benthic macroalgae form an important part of temperate marine ecosystems, exhibiting a complex three-dimensional character which represents a vital foraging and spawning ground for many juvenile fish species. In this research, image-based techniques for classification of multibeam backscatter are explored for the detection of benthic macroalgae at Cashes Ledge in the Gulf of Maine, USA. Two classifications were performed using QTC-Multiview, differentiated by application of a threshold filter, and macroalgal signatures were independently extracted from the raw sonar datagrams in Matlab. All classifications were validated by comparison with video ground-truth data. The unfiltered classification shows a high degree of complexity in the shallowest areas within the study site; the filtered demonstrates markedly less variation by depth. The unfiltered classification shows a positive agreement with the video ground-truth data; 82.6% of observations recording Laminaria sp., 39.1% of Agarum cribrosum and 100.0% (n = 3) of mixed macroalgae occur within the same acoustically distinct group of classes. These are discrete from the 8.1% recorded agreement with absences and nulls (>40 m) of macrophytes (n = 32) from a total of 86 ground-truth locations. The results of the water column data extraction (WCDE) show similar success, accurately predicting 78.3% of Laminaria sp. and 30.4% of A. cribrosum observations. 相似文献
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介绍了以拓普康IS201影像型3维扫描全站仪获取的点云数据构造不规则三角网(TIN)计算土石方量的方法,并对IS系统在齐齐哈尔市碾子山区东海采石场土石方测量中的应用情况进行了详细的介绍和分析。实际应用表明,IS201影像型3维扫描全站仪操作简便,系统测量工作效率非常高,精度更高、更可靠。 相似文献
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截至2014年底,我国共有2 729个自然保护区,面积近1.5万km2。实景三维数据具有效率高、纹理清晰、内容全面精细等特点,在支撑自然保护区规划、建设、管理方面发挥很大作用。本文分析了我国自然保护区的现状:1)按级别,县级自然保护区个数最多,国家级自然保护区总面积最大;2)按主管部门,林业主管的自然保护区个数最多,总面积也最大;3)按所属类型,森林生态自然保护区个数最多,荒漠生态自然保护区总面积最大。本文给出了实景三维地理信息系统的设计框架并在国家级自然保护区开展了实践。 相似文献
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B. Yoo 《International journal of geographical information science》2013,27(1):24-46
The depiction and navigation of large-scale urban landscapes are limited by the great cost of traditional computer-aided design (CAD) models for large urban environment in terms of both the labor of data entry and the runtime computational expense. This article presents a hybrid modeling approach that enables rapid urban model production from legacy spatial data. Our scheme fills the gap between the low geometry models, such as photo-textured digital terrains, and high geometry models, such as true three-dimensional CAD models. To achieve optimal performance in modeling and rendering, we employ bilayered displacement mapping consisting of global displacement mapping (GDM) for terrains and local displacement mapping (LDM) for buildings. The LDM is performed only within image processing so that the complexity of the models depends only on the area of an urban model. We present a use case of rapid urban model production to compare our approach with the traditional polygonal urban models of a widely used geo-browser. 相似文献
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Efforts to develop a procedurally robust method for automated classification of multibeam backscatter have taken a variety of approaches (e.g., image-based, textural, angular range analysis). For image-based classification, little research has focused on the roles of operational parameters of vessel and sonar system in affecting the final classification. Repeat multibeam surveys (2005 and 2006) conducted at the same area with different sounding densities were classified using QTC-Multiview. Comparison of class areas revealed 78% agreement between classifications derived from the two surveys. Cross-tabulation of ground truth video and class demonstrate 71% agreement in the low-density survey and 77% for the high-density. Differences between classifications are primarily attributed to variation in along track data density, errors in the compensation process, and/ or insufficient quality control of the input data. Natural change detection at the scales observed was determined not to be practically discernable from the errors associated with the classification process. 相似文献
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Sing Bing Kang 《ISPRS Journal of Photogrammetry and Remote Sensing》1998,53(6):342-353
Conventional methods for scene visualization involve 3-D model reconstruction and direct rendering of the model. More recently, however, there has been an increasing interest in an alternative means for novel view synthesis, namely image-based rendering. It refers to a collection of techniques for creating new views directly from a set of input images; these images act as the scene `model'. This paper describes in detail a particular subset of image-based rendering techniques, which we refer to as geometrically valid pixel reprojection techniques. These techniques are based on established bilinear and trilinear image constraints in the forms of the fundamental matrix and trilinear tensor, respectively. We also describe an image-based rendering technique that uses as input a collection of cylindrical panoramic images. 相似文献
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为了全面提高1∶50000数据库的信息现势性和要素完整性,我国"十一五"期间组织实施了国家1∶50000数据库更新工程。介绍该工程总体技术研究与技术创新工作,包括研究设计以地形数据全要素更新、全区域变化检测和全过程质量控制为主要特征的1∶50000数据库全面更新模式,研究提出符合我国大面积快速更新实际需要的缩编更新优先、影像一体化更新为主的主体更新方法,设计研制规模化更新所需的生产技术系统,制定配套的生产技术规定,建立规模化更新生产业务体系,并在全国大规模更新生产中广泛使用。 相似文献
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