说明：  GDAL是一个操作各种栅格地理数据格式的库。包括读取、写入、转换、处理各种栅格数据格式，它使用了一个单一的抽象数据模型就支持了大多数的栅格数据
(GDAL is an operation of various raster geographic data format library. Including read, write, convert, handle a variety of raster data formats, it uses a single abstract data model is supported by the majority of raster data)