*Base on GDAL(Geospatial Data Abstraction Library)
* Digital Elevation Model(DEM)
* Working with geographic data
*read tif file
*write tif file
*GDAL is a translator library for raster and vector geospatial data formats that is released under an X/MIT style Open Source License by the Open Source Geospatial Foundation. As a library, it presents a single raster abstract data model and single vector abstract data model to the calling application for all supported formats.
* It also comes with a variety of useful command line utilities for data translation and processing.
