多少年以来,除了正射投影下的各种比例尺地形图外,还有一种人们总是难以割舍的地图表现形式,那就是影像地图。尽管它是中心投影,图内比例尺不够均匀、精度不高,但其真实而丰富的即时影像,对于读者来说,不必具备专门的地图知识,也无须讲解,是再直观不过了。也许正是这一原因,影像地图从几张黑白航空像片的简单拼接开始,发展到正射影像图,彩红外航片乃至卫星遥感彩片图,随着科技手段的进步而不断更新换代。为叙述上的方便
本文讨论了单张平面地图、地图边框线及图形边界的数字化数据处理方法,从而为形成平面数据库提供方法和手段。
本文根据新的国标《图式》,GIS对数据的基本要求以及AUTOCAD自身特点,浅谈数字地形图编辑技术要求,对生产实际具有指导意义。
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