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For tall buildings,terrestrial laser scanner cannot obtain complete point clouds for parts above the cornice.Therefore in the mapping of ancient architectures,we use unmanned helicopter with a high-pixel digital camera to do the shooting and thus can get a complete point cloud model for the eaves.In China,we have a large number and wide distribution of ancient architectures.Their eaves have something in common: two-slope roof or four-slope roof with rich decorations on the ridges.After lots of mapping tests,we can summarize typical photogrammetric mapping methods,including the number and position of baselines,the setting of control points,as well as the shooting techniques for such special building elements as glazed tiles and Wenshou (animal decorations on the ridges) so as to reduce the difficulty of field work,increase efficiency and mapping success.The data standards of low-altitude mapping of eaves are as follows: the overall point cloud precision and resolution should reach centimeter level; the four sides should be complete with no blind zones; a complete 3D surface model should be obtained for such building elements on the ridge as Wenshou,with millimeter resolution and accurate real color information.This paper also explains the effect of merging eave point clouds obtained from lowaltitude photogrammetry with point clouds (of parts below the cornice) obtained by laser scanners.