Application of computer vision algorithms in photogrammetric approaches has been the recent trend, which makes the photograph based point cloud and 3D model generation comparable to laser scanning technology. Moreover, photogrammetric 3D model has few advantages and conveniences such as higher accuracy for shorter imaging distances (< 5 m), relatively easy data collection even in difficult terrain, high radiometric resolution of final point cloud and relatively low purchase costs. There are a many commercially available software which have the capability of 3D view generation. However they are usually expensive, generic and complex for non experts. Currently users have access to few free and open source photogrammetric software, or algorithms containing sub-steps of image processing, as well as multiple web services enabling object reconstruction from images through the internet and/or remote services. With this background, efforts have been made to compile the available packages of computer vision and photogrammetry to bring out a single platform solution “Trivim” for 3D street view generation. Trivim, an open source application, is a step forward which provides the capability of 3D street view generation with measurements comparable to ground scenario. In addition to it, it facilitates the association of a 3D database to each building segment. This application will enable users to perform onsite direct camera calibration, estimation of time and number of photographs for a particular project and creation of geo-referenced point cloud using sequence of overlapping photographs along with GPS coordinates of the camera stations. The application results in 3D models with sub meter accuracy in planimetry as well as height. 3D GIS database can be attached to the individual segments of the model and database query can be performed. The 3D models with segment wise database can be used for a variety of applications such as urban utility and property management, emergency services management, disaster loss estimation, potential tax estimation for an urban area to name a few. The package is designed such that data collection and other usual procedure such as camera calibration, scaling and geo-referencing of point, user defined segmentation for urban scenario are easier compared to other commercial generic packages of photogrammetry. This enables the utilization of any camera type, including cameras of smart phones as a measurement device. This package generates the photo textured 3D models with user assigned database by processing the input photographs and location of camera. These models can be visualized on geoportals and database query can be performed. The generated 3D model in .kmz format which can be used in any 3D GIS software for further analysis.
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