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The paper presents the state of the art of quality control of photogrammetric and laser scanning data captured by airborne sensors. The described subject is very important for photogrammetric and LiDAR project execution, because the data quality a prior decides about the final product quality. On the other hand, precise and effective quality control process allows to execute the missions without wide margin of safety, especially in case of the mountain areas projects. For introduction, the author presents theoretical background of the quality control, basing on his own experience, instructions and technical documentation. He describes several variants of organization solutions. Basically, there are two main approaches: quality control of the captured data and the control of discrepancies of the flight plan and its results of its execution. Both of them are able to use test of control and analysis of the data. The test is an automatic algorithm controlling the data and generating the control report. Analysis is a less complicated process, that is based on documentation, data and metadata manual check. The example of quality control system for large area project was presented. The project is being realized periodically for the territory of all Spain and named National Plan of Aerial Orthophotography (Plan Nacional de Ortofotografía Aérea, PNOA). The system of the internal control guarantees its results soon after the flight and informs the flight team of the company. It allows to correct all the errors shortly after the flight and it might stop transferring the data to another team or company, for further data processing. The described system of data quality control contains geometrical and radiometrical control of photogrammetric data and geometrical control of LiDAR data. According to all specified parameters, it checks all of them and generates the reports. They are very helpful in case of some errors or low quality data. The paper includes the author experience in the field of data quality control, presents the conclusions and suggestions of the organization and technical aspects, with a short definition of the necessary control software.
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