DEM地形提取工具，可针对卫星图片提取高程，比如最常用的Google earth，方便实用。-DEM terrain extraction tool that can extract the elevation for the satellite images, such as the most commonly used Google earth, convenient and practical.

LibNav 包括在航空航天导航领域中一些常用的工具包，包括：时间信息的处理、航天工程、向量、矩阵的常用算法、数值计算方法（包括卡尔曼滤波）、车辆的运动学仿真、导航设备的仿真（VOR/DME）-LibNav is a library of support routines designed for use by programmers developing applications in the navigation area. The library consists of several