说明：  读取hdf，HDF 是美国国家高级计算应用中心（National Center for Supercomputing Application）为了满足各种领域研究需求而研制的一种能高效存储和分发科学数据的新型数据格式。一个HDF文件中可以包含多种类型的数据，如栅格图像数据，科学数据集，信息说明数据。这种数据结构，方便了我们对于信息的提取。例如，当我们打开一个HDF图像文件时，除了可以读取图像信息以外，还可以很容易的查取其地理定位，轨道参数，图像噪声等各种信息参数。HDF 的数据结构是一种分层式数据管理结构。
(read hdf,HDF is the National Center for Supercomputing application (National Center for Supercomputing Application) is a new efficient storage and data dissemination of scientific data format in order to meet the demand of various fields and the development of the. A HDF file can contain multiple types of data, such as raster image data, scientific data sets, and information indicating data. This data structure facilitates our extraction of information. For example, when we open a HDF image file, in addition to reading the image information, we can easily find its geographical location, track parameters, image noise and other information parameters. The data structure of HDF is a hierarchical data management structure.)