Data Type       =MSG GVI weekly composite
Data sub-folder =~/SGVI/SGVI_7days
Example file    =MSG2.FD.C01.2008001.hdf            (daily map)
Example file    =MSG2.FD.C07.2008001.S001.E007.hdf  (weekly map)

[Data Format]
 1. File name convention: 
    ppp.Ccc.yyyyddd.hdf
    ppp.FD.Ccc.yyyyddd.Ssss.Eeee.hdf 
 
    where, 
           ppp:  prefix, MSG1.FD or MSG2.FD
           cc:   number of composite days 
           yyyy: year
           ddd:  day of year
           sss:  start day (day of the year)
           eee:  end day (day of the year)


 2. File attributes: 
    The numebrt of attributes of this file =            0

 3. SDS List:
     SDS 1: time_of_input_images[57], type=INT,                NATTS=1
     SDS 2: NDVI[3712,3712],          type=INT,   fill=-32768, NATTS=3
     SDS 3: pixel_time[3712,3712],    type=INT,   fill=0,      NATTS=2
     SDS 4: solar_zenith[3712,3712],  type=INT,   fill=-32768, NATTS=3
     SDS 5: solar_azimuth[3712,3712], type=UINT,  fill= 65535, NATTS=3
     SDS 6: REFL1[3712,3712],         type=UINT,  fill=0,      NATTS=3
     SDS 7: REFL2[3712,3712],         type=UINT,  fill=0,      NATTS=3
     SDS 8: REFL3[3712,3712],         type=UINT,  fill=0,      NATTS=3
     SDS 9: BT04[3712,3712],          type=UINT,  fill=0,      NATTS=3
     SDS 10: BT09[3712,3712],         type=UINT,  fill=0,      NATTS=3
     SDS 11: BT10[3712,3712],         type=UINT,  fill=0,      NATTS=3

 4. SDS Attributes:
   SDS  time_of_input_images
           #1: note= hour*100 + minute

   SDS  NDVI
           #1: UNITS= NONE
      	    #2: _FillValue= -32768
   	    #3: scale=0.00100000

   SDS  pixel_time
           #1: UNITS= HHMM
	    #2: _FillValue=0
           
   SDS  solar_zenith
           #1: UNITS= Degree
     	    #2: _FillValue= -32768
    	    #3: scale= 0.0100000

   SDS  solar_azimuth
           #1: UNITS= Degree
      	    #2: _FillValue =65535
	    #3: scale= 0.0100000

   SDS REFL1,2,3
           #1: UNITS= NONE
           #2: _FillValue = 0
           #3: scale= 0.00100000

   SDS BT4, ... BT10
           #1: UNITS= K
	    #2: _FillValue=0
           #3: scale=    0.0100000