AN END-TO-END AIRBORNE DIGITAL MAPPING SOLUTION, FOR RAPID DIRECTLY GEOREFERENCED ORTHOPHOTO PRODUCTION

摘要

Over the last decade, the evolution of airborne ortho-mapping has been focused on two important aspects: data collection and post-processing efficiency. First, the well developed Direct Georeferencing simplifies the data post-processing which eliminates the dependency of using ground control points as part of the production workflow. This technology has been well studied by EUROSDR (formerly OEEPE) in 2001. Significant cost saving has been one of the direct benefits compared to the conventional film based products. Second, the emerging use of an all-digital environment compresses the timeline for organizations to move into the use of digital sensor technology. Over the last few years, a number of large, medium and small format digital camera systems have been available as a complete replacement for film camera. Further, the flexibility of digital data collection further expands the use of such orthomapping products. Currently, temporal requirements have become a user priority in order to get final products processed as quickly as possible, while remaining sensitive to image quality expectations. However, users are challenged to educate themselves about the complex digital sensor technology, to understand what the systems can do, and to choose the "right tool for the job". Furthermore, the existing equipment being used in traditional photogrammetry workflow remains an invisible barrier for firms wishing to employ the Direct Georeferencing technology, which can bring them into a different market segment. The DSS RapidOrtho~(TM) System integrates enabling technologies and advanced workflows to generate application-specific mapping products for the Rapid Response market segments. The DSS RapidOrtho embraces the Plan-Fly-Produce concept by combining the Position and Orientation System (POS) and the Medium format Digital Sensor System (DSS) technology. First, the POS provides real-time navigation solution that is the essential information for calculating the exterior orientation parameter of each image capture. Second, the single lens, single CCD array medium format camera is the only camera type capable of generating single frame imagery with minimum image post-processing efforts, compared to other medium and large format camera with multiple lens and/or CCD array. At a 22 and now 39 MegaPixel resolution, the camera is geometrically and radiometrically calibrated with USGS certification, providing the user with a mapping quality product. The DSS RapidOrtho~(TM) solution for the Rapid Response market segment provides three major product categories via a complete data collection and processing workflow. First, the RapidOrtho product focuses on Disaster Data collection for first responders for immediate evaluation of imagery. Second, the Precision RapidOrtho product proves improved accuracy that allows further analysis of the data such as change detection. Finally, the High Precision RapidOrtho product combines all of the above features while being self-sufficient to produce rapid 3D visualization, in the combination of DTM self-extraction. In this paper, case examples for the Rapid Response applications highlighting specific data collection efforts and processing efficiencies will be demonstrated using the RapidOrtho~(TM) system. In addition, a detailed description on the data processing workflow will be demonstrated in some details.