3D Building Modelling with Digital Map, Lidar Data and Video Image Sequences   总被引：1，自引：0，他引：1  

Yongjun  Zhang  Zuxun  Zhang  Jianqing  Zhang  Jun  Wu 《The Photogrammetric Record》2005,20(111):285-302

Three-dimensional (3D) reconstruction and texture mapping of buildings or other man-made objects are key aspects for 3D city landscapes. An effective coarse-to-fine approach for 3D building model generation and texture mapping based on digital photogrammetric techniques is proposed. Three video image sequences, two oblique views of building walls and one vertical view of building roofs, acquired by a digital video camera mounted on a helicopter, are used as input images. Lidar data and a coarse two-dimensional (2D) digital vector map used for car navigation are also used as information sources. Automatic aerial triangulation (AAT) suitable for a high overlap image sequence is used to give initial values of camera parameters of each image. To obtain accurate image lines, the correspondence between outlines of the building and their line features in the image sequences is determined with a coarse-to-fine strategy. A hybrid point/line bundle adjustment is used to ensure the stability and accuracy of reconstruction. Reconstructed buildings with fine textures superimposed on a digital elevation model (DEM) and ortho-image are realistically visualised. Experimental results show that the proposed approach of 3D city model generation has a promising future in many applications.  相似文献   

Assessing plantation canopy condition from airborne imagery using spectral mixture analysis and fractional abundances     

《International Journal of Applied Earth Observation and Geoinformation》2005,7(1):11-28

Pine plantations in Australia are subject to a range of abiotic and biotic damaging agents that affect tree health and productivity. In order to optimise management decisions, plantation managers require regular intelligence relating to the status and trends in the health and condition of trees within individual compartments. Remote sensing technology offers an alternative to traditional ground-based assessment of these plantations. Automated estimation of foliar crown health, especially in degraded crowns, can be difficult due to mixed pixels when there is low or fragmented vegetation cover. In this study we apply a linear spectral unmixing approach to high spatial resolution (50 cm) multispectral imagery to quantify the fractional abundances of the key image endmembers: sunlit canopy, shadow, and soil. A number of Pinus radiata tree crown attributes were modelled using multiple linear regression and endmember fraction images. We found high levels of significance (r² = 0.80) for the overall crown colour and colour of the crown leader (r² = 0.79) in tree crowns affected by the fungal pathogen Sphaeropsis sapinea, which produces both needle necrosis and chlorosis. Results for stands associated with defoliation and chlorosis through infestation by the aphid Essigella californica were lower with an r² = 0.33 for crown transparency and r² = 0.31 for proportion of crown affected. Similar analysis of data from a nitrogen deficient site produced an outcome somewhat in between the other two damaging agents. Overall the sunlit canopy image fraction has been the most important variable used in the modelling of forest condition for all damaging agents.  相似文献   

基于变化检测的视频对象提取及后继帧的对象跟踪     

种衍文  江柳  沈未名 《武汉大学学报(信息科学版)》2006,31(8):748-751

提出一种多尺度帧间边界变化检测方法，将当前图像划分为变化区域和非变化区域，变化区域内采用基于Hausdorff距离跟踪器找到对象在后继帧的最佳匹配位置；然后利用Snake模型拟合该位置上的非刚性形变，得到对象真实边缘；最后采用一种基于距离变换的最短路径法使开环闭合。  相似文献   

跨断层形变测量场地图形分析及设计     

祝意青  胡斌 《地震地磁观测与研究》1998,19(5):30-37

在分析了青藏体北缘跨以形变测量场地图形状态的基础上,论述了进行优化设计的必要性及新的图形设计的主要内容：（１）以ＧＰＳ控制整个断裂、以水冷、测距、基线、重力等测量手段监测各个场地测点形成的三维地形物重力变化信息;（２）断层水准、重力按新的标石裂线阵设;（３）断层水平形变可根据运动状态的不同,按“走滑型”和“倾滑型”布设;（４）场地水冷、重力定期水准、重力联测,场地水平没距网定期与区域ＧＰＳ网联测,  相似文献   

计量用水智能监测系统的设计与实现     

黄静  郭勇  李乃玮 《物探化探计算技术》2003,25(3):237-240

水位传感器与单片机智能遥测终端相配合设计的计量用水智能监测系统可以通过电话线，将计量用水信息远程数传到监控中心，并在监控中心生成各种图文、报表。通过对图文、报表的分析，实现对智能遥测终端的远程监控。该系统将在水利建设中发挥重要作用。  相似文献   

错误多发异质网络环境下视频编码系统的总体设计     

沈未名  朱立  李国宽 《武汉大学学报(信息科学版)》2002,27(1):23-27

描述了针对错误多发异质的网络环境进行视频编码系统总体设计的全过程。分析了外部需求，提出了改进视频表现、增强容错能力和提供可分级编码能力的系统设计目标。在简要介绍H．263＋协议的全部16个可选的高级编码模式的基础上，重点分析了设计对系统是否采用某个高级编码模式进行取舍的理由。对视频数据流的打包、错误掩蔽和错误跟踪的机制等方面进行了讨论。实际应用表明，根据本文设计进行的系统实现完全达到了原定的系统设计目标。  相似文献   

The Development of the Chagas' Online Data Entry System (CODES-GIS)     

Jason K Blackburn  rew Curtis  Frances Currin Mujica  Farrell Jones  Patricia Dorn  Rosamond Coates 《Transactions in GIS》2008,12(2):249-265

This article describes a web‐based data entry and GIS‐driven mapping system designed for an ethnographic and entomological survey of Chagas’ disease, an emerging zoonotic disease, and Triatoma dimidiata, a primary vector, in the Los Tuxtlas region of Veracruz, Mexico. To better understand this disease in the region, a collaborative, multi‐disciplinary study was initiated to conduct a spatial investigation of T. dimidiata and a community‐by‐community survey of local perceptions of the disease. In order to facilitate such a collaborative effort the CODES‐GIS was developed. This system allows for (near) real‐time mapping, analyses, disease reporting, and results sharing. CODES‐GIS provides a framework for a research team working in a remote area with limited technology, software, or GIS expertise to benefit from (near) real‐time spatial analyses performed at collaborating institutions. The system is bi‐directional, where field personnel can upload data to the system for field‐based map production. Likewise, laboratory personnel can upload diagnostics data for viewing by field personnel. In this way, the system provides a virtual link between the field and the laboratory to increase the speed at which results are returned to the local community. The CODES‐GIS is described along with a selection of study results.  相似文献   

一种改进的UAV视频序列影像镶嵌方法     

于文率余旭初  张鹏强周俊 《测绘学院学报》2007,24(6):415-418

视频序列影像自动镶嵌是UAV视频影像处理应用中的基础环节和重要研究方向。针对序列影像镶嵌过程中,由于配准精度不高、误差累积所导致的拼接错位严重,镶嵌结果不理想的情况,从提高特征匹配的精度和准确度出发,提出了一种改进型的UAV视频序列影像自动镶嵌方法。通过对特征匹配结果的精细化处理,保证了影像配准的正确性,取得了较好的镶嵌结果。  相似文献   

海南气象影视广告营销及发展对策分析   总被引：1，自引：0，他引：1  

黄光瑞 《气象研究与应用》2007,28(4):82-85

针对海南气象影视广告业现状和存在问题,分析了海南气象影视广告媒体的优劣势,并提出了相应的解决方法和经营策略,从而推动气象影视广告业不断创新发展。  相似文献   

GIS应用现状及发展趋势探讨   总被引：10，自引：1，他引：9  

梁红莲  刘登忠 《物探化探计算技术》2001,23(1):68-73,92

作者在文中简要介绍GIS一般功能的同时,综述了GIS的应用现状。在此基础上,讨论了传统GIS、分布式GIS（C／S）和WEB GIS系统的集成策略及其优缺点,指出WEB GIS系统集成将是GIS系统在21世纪的发展趋势。  相似文献