modisread.py 文件源码

def read_band(fileObj,key,b,d):
    '''reads MODIS data,scale them with the Solar Zenith and returns one band'''
    print 'read image '+str(b)+' from dataset '+str(key) +'... '
    dsObj=fileObj.select(key)
    B=sp.array(dsObj.get(),sp.float32) # float32
    attr=dsObj.attributes()
    scale=attr['reflectance_scales'][b]
    offset=attr['reflectance_offsets'][b]
    dn=B[b,:,:]
    bad_ind=(dn>=32767).nonzero() # Bit16 zeigt fehlerhafte Messungen an
    band=(scale*(dn-offset))/sp.cos(d['SolarZenith'])
    band[bad_ind]=0
    print ' done'
    return band