Unban Three Dimensional Modeling And Its Precision Analysis By Use Of Digital Mapping Camera (DMC) Data

Urban management is a necessary requirement for sustainable urbandevelopment，is an important indemnification for the rapid development of the city.The characteristic of the modern city have more and more people, more bigger area，more closely between the cities. Complex urban environment requires scientific,effective and proper management methods and practices.3D city building can find abreakthrough for this problem to settle.3D City based Geographic Information System is a digital important part ofurban construction, is composed of the total feature topographic maps, digitalorthophoto maps, digital elevation models,3D city models and other basicinformation data， and, establish a basis spatial database combining with theunderground pipelines, planning, land, transportation emergency command and otherindustry information. Application developing on this basis, to build a real, intuitive,convenient monitoring city-based3D GIS platform for the applications of differentsectors to query, statistics and analysis. Establishing3D digital city by using highresolution aerial images can provide a virtual urban environment, achieve ageographic information sharing, communication and publishing through internettechnology and establish the foundation for a more scientific, standardized andrational use of resources, and promoting the sustainable urban development ofinformation technology services.3D city models include the spatial features of above and below ground surfaceand the natural landscapes such as land, lakes and vegetation etc. and various culturallandscapes such as buildings，roads, pipelines，geological structure and so on.3Dcity model is the basic data of the digital city construction, are the important part ofthe urban three-dimensional geographic information system, is the basis of theanalysis of spatial data. The style of obtaining the basic data and the methods ofbuilding the Urban3D model decide the timeliness an the efficiency of establishingthe three-dimensional model, and accuracy of three-dimensional model directlyimpact on the accuracy of the data analysis.In this paper, taking Langfang planning area as the study area and taking DMCaerial photographic survey data as the data source for the city establish technological method of three-dimensional model and modeling accuracy assessment, the mainfindings are as follows:1. Formed a set based on aerial images DMC city three-dimensional modeling ofthe production methods from summing technical methods and processes of the citythree-dimensional, including data preprocessing, aerotriangulation, DEM dataproduction, model framework data acquisition, modeling texturing and so on.2. Summed up the best way of using the DMC aerial photogrammetry dataprecise3D modeling large urban area based on different data sources through the citythree-dimensional modeling methods and the advantages and disadvantages of variousmethods of analysis.3. By the method of following the uniform distribution and randomly selected,using high-precision topographic field survey data to evaluate and verify the accuracyof characteristics points and representativeness side length. Summed that using theDMC aerial imagery modeling three-dimensional model accuracy is relativelyuniform, the location of the building has less impact on accuracy, and the precisioncan meet the construction of three-dimensional urban management informationsystem, which can also provide scientific decision-making for the city administration.4. This study provides proven technology of3D city modeling based on DMCaerial image data, which can be used in the construction of three-dimensionalinformation city and provide a scientific ideas and methods for3D city management.