A multiple terrestrial laser scanner (TLS) integration approach is proposed for the fine surveying and 3D modeling of ancient wooden architecture in an ancient building complex of Wudang Mountains, which is located in very steep surroundings making it difficult to access. Three-level TLS with a scalable measurement distance and accuracy is presented for data collection to compensate for data missed because of mutual sheltering and scanning view limitations. A multi-scale data fusion approach is proposed for data registration and filtering of the different scales and separated 3D data. A point projection algorithm together with point cloud slice tools is designed for fine surveying to generate all types of architecture maps, such as plan drawings, facade drawings, section drawings, and doors and windows drawings. The section drawings together with slicing point cloud are presented for the deformation analysis of the building structure. Along with fine drawings and laser scanning data, the 3D models of the ancient architecture components are built for digital management and visualization. Results show that the proposed approach can achieve fine surveying and 3D documentation of the ancient architecture within 3 mm accuracy. In addition, the defects of scanning view and mutual sheltering can overcome to obtain the complete and exact structure in detail.

As an important part of the public service and educational infrastructures for national culture and heritage culture, a virtual museum presents the user experience of a real museum, with visitors, educators, and tourists interacting with the prepared digital culture contents by a mouse, touch panel, and other augmented reality devices. The goal of virtual museum is to help students and visitors to move around the virtual museum space freely and generate experience and satisfaction from the fruition of cultural heritage anytime, anywhere, and from any device. This study presents a hybrid three-dimensional virtual museum based on panoramic images and three-dimensional models. A technical framework of hybrid three-dimensional virtual museum is proposed on the basis of a typical three-tier architecture, which includes the data layer, technique supporting layer, and application layer. A hybrid three-dimensional data organization approach with geo-referenced sequence panoramic images and three-dimensional models is designed to build the data layer of hybrid three-dimensional virtual museum. A three-dimensional scene of geo-referenced sequence panoramic images and three-dimensional models is created in real time using Unity three-dimensional and web service under the mobile Internet environment for hybrid three-dimensional virtual museum. The different applications of hybrid three-dimensional virtual museum based on the data layer and technique infrastructure are designed to achieve handheld virtual museum guidance and navigation, three-dimensional browsing, and heritage culture information query for visitors with smartphones to access anytime and anywhere. As an example, a hybrid three-dimensional virtual museum application for Jinsha Archaeological Site Museum is developed with the proposed approach. The geo-referenced sequence panoramic images of museum galleries, together with three-dimensional models of cultural relics, can integrate seamlessly to a three-dimensional reality-based museum space where users can move around the space actively and freely with all kinds of personal computer and smartphone clients.

The uncertainty of indoor Wi-Fi positioning is susceptible to many factors, such as sensor distribution, the internal environment (e.g., of a shopping mall), differences between receivers, and the flow of people. In this paper, an indoor pedestrian trajectory pattern mining approach for the assessment of the error and accuracy of indoor Wi-Fi positioning is proposed. First, the stay points of the customer were extracted from the pedestrian trajectories based on the spatiotemporal staying patterns of the customers in a shopping mall. Second, the drift points were distinguished from the stay points through analysis of noncustomer behavior patterns. Finally, the drift points were presented to calculate the errors in the pedestrian trajectories for the accuracy assessment of the indoor Wi-Fi positioning system. A one-month indoor pedestrian trajectories dataset from the Xinxiang Baolong shopping mall in Henan Province, China, was used for the assessment of the error and accuracy values with the proposed approach. The experimental results were verified by incorporating the distribution of the AP sensors. The proposed approach using big data pattern mining can explore the error distribution of indoor positioning systems, which can provide strong support for improving indoor positioning accuracy in the future.

Street view (panoramic view) services have begun to shift from PC platforms to mobile smart devices. Considering the capabilities of smart terminal devices, a 3608 spherical level of detail (LoD) model for mobile street view services that renders panoramic images on the inner surface of a sphere via LoD is proposed in this article. Panoramic images are segmented into tiles and organized in a pyramid tile structure for LoD rendering to improve the rendering efficiency of the proposed model. A projection model between panoramic images and the spherical surface is presented to map the panoramic tiles on the spherical graticule. A street view-rendering algorithm of panoramic images is proposed with the rendering function of OpenGL for Embedded Systems (OpenGL ES).A street view service app running on Android, based on the proposed approach, is implemented to assess two aspects of the panoramic view model, namely visualization effect and efficiency. Experiment results reveal that the 3608 spherical LoD model of the panoramic image can display 3D street view scenes better than the cubic panoramic view model. The proposed model also has an excellent 3D visualization effect and high-efficiency rendering ability for mobile street view services.Therefore, it is applicable in large-scale mobile street view services both online and offline and in augmented reality navigation. K E Y W O R D S level of detail, mobile device, panoramic image, rendering, spherical, street view 1 | I NTR OD U CTI ON In the past, people expressed the real world abstractly through all types of maps, such as general, thematic, image, and 3D maps. In May 2007, in a collaboration with Stanford University called CityBlock, Google launched Google Street View (GSV) with 3608 panoramic images for the first time (Anguelov et al., 2010). The idea was to provide a street view of driving along every street in the world by taking pictures of all buildings and roadsides. At present, worldwide Transactions in GIS. 2017;21:897-915.wileyonlinelibrary.com/journal/tgis street view environments can be routinely captured with land-based mobile mapping systems (Li, Hu, & Chen, 2009;Anguelov et al., 2010). The extensive availability of street-level image data has proven the popularity of the street view environment among users; this environment delivers useful information that was not previously available. Street view (panoramic view) with a 3608 panoramic image has been and continues to be an exciting adventure in globalscale and street-level photo collection and service. As an online virtual imaging application, GSV allows a user to view and navigate through 3608 panoramic images and observe streets and neighborhoods virtually (Li et al., 2009;Fang, Li, & Zhang, 2011;Lewis, Fotheringham, & Winstanley, 2011). One can navigate forward and backward and then up and down as well as zoom in and out. Chinese Internet service providers, such as Tencent and Baidu, also recently launched panoramic view services in succession; these services can provide real 3D scenes for the exp...

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