CAJ | 학술논문

数字高程模型DEM是一种十分重要的数据格式，在很多领域都有广泛应用。通常，DEM数据较大。对于海量DEM数据的处理，由于受到PC机性能的限制，如果不对地形数据进行简化处理，将会影响显示效果。因此，为了在图形工作站上达到令人满意的实时显示和交互操作效果，应采取一定的算法来简化地形数据。本文利用金字塔影像对DEM数据进行分层分块存储，同时，采用OpenGL作为底层图形驱动程序，对DEM存储结果进行浏览。实验结果表明，分层分块存储DEM数据，大大减少了硬盘访问时间，提高了浏览速度。另外，还根据需求对DEM数据进行局部浏览，进一步提高了访问速度。
수자고정모형DEM시일충십분중요적수거격식，재흔다영역도유엄범응용。통상，DEM수거교대。대우해량DEM수거적처리，유우수도PC궤성능적한제，여과불대지형수거진행간화처리，장회영향현시효과。인차，위료재도형공작참상체도령인만의적실시현시화교호조작효과，응채취일정적산법래간화지형수거。본문이용금자탑영상대DEM수거진행분층분괴존저，동시，채용OpenGL작위저층도형구동정서，대DEM존저결과진행류람。실험결과표명，분층분괴존저DEM수거，대대감소료경반방문시간，제고료류람속도。령외，환근거수구대DEM수거진행국부류람，진일보제고료방문속도。
Digital Elevation Model is a very important data format. In many areas, DEM data has a wide range of applications. Usually, DEM data is huge. For the processing of the mass DEM data, due to the restrictions of PC-performance, the display of DEM data is not ideal. Therefore, in order to get a satisfactory real-time display and interaction effects on the graphic workstation, we must simplify terrain. This paper uses hierarchical pyramid images to store the DEM data on the basis of the blocks. At the same time, we can view the stored DEM data using OpenGL as the underlying graphics driver. The results shows that hierarchical storage of the DEM data based on the blocks will greatly reduce the time of access of hard disk, and improve the speed of browsing. In addition, we partially browse DEM data according to the requirement, which will further increase the access speed.