maven apache wrote:


2010/1/12 Frank Warmerdam <[email protected] <mailto:[email protected]>>

    maven apache wrote:

           It suggests that GDAL is not recognising the georeferencing
        of the
           data.  The actual pixel values will hopefully still be accessed
           properly.

           I would actually need to see the whole gdalinfo report on the
        subdataset
           to be certain that GDAL is not finding another form of
        georeferencing,
           like GCPs or geolocation arrays.  These will not be reflected
        in the
           corner coordinates report (unfortunately).

        Thank you very much , I will paste the result.
        The whole gdalinfo metadata can be found here:
        http://dpaste.com/143948/
        And the info of  SUBDATASET_4_NAME  can be found here:
        http://dpaste.com/143949/


    "Maven",

    It seems that GDAL does not recognise the metadata on this file that
    contains the georeferencing.  However, you can fairly easily apply the
    georeferencing as part of the translation something like this:

    gdal_translate \
     HDF5:"d23.he5"://HDFEOS/GRIDS/ColumnAmountO3/Data_Fields/ColumnAmountO3
    \
     -a_ullr -180 90 180 -90

Oh thanks, it works!
But I have two questions:
1) how do you know the -a_ullr parameter?

Maven,

I read through the metadata reported by gdalinfo:

  ColumnAmountO3:GCTPProjectionCode=0
  ColumnAmountO3:Projection=Geographic
  ColumnAmountO3:GridOrigin=Center
  ColumnAmountO3:GridSpacing=(0.25,0.25)
  ColumnAmountO3:GridSpacingUnit=deg
  ColumnAmountO3:GridSpan=(-180,180,-90,90)
  ColumnAmountO3:GridSpanUnit=deg
  ColumnAmountO3:NumberOfLongitudesInGrid=1440
  ColumnAmountO3:NumberOfLatitudesInGrid=720
  HDFEOS INFORMATION:HDFEOSVersion=HDFEOS_5.1.9

This makes it pretty clear the image is a fullworld image
in geographic coordinates.  If this is a common metadata
format the driver could be updated to recognise it automatically.
Unfortunately there seem to be a variety of ways of storing
georeferencing for different HDF5 products.

2) Since some part of the tiff is blank, it is not scanned by the sensor. so I want fill them manually,so I wonder the gdal library can do it ? Also I want to add some new tags to the tif and I want to use java to implement it/

Are you wanting to interpolate these nodata areas from nearby valid
data?  There are many ways of doing this, but gdal_nodatafill.py may
prove helpful to you as a utility.  If you want to do it from Java
you will need to call the FillNodata() function which should be
available in the GDAL Java bindings.  More info on this function at:

  http://www.gdal.org/gdal__alg_8h.html#0a079afef61968f224b159d48423d1c6
  http://www.gdal.org/gdal_fillnodata.html

Best regards,
--
---------------------------------------+--------------------------------------
I set the clouds in motion - turn up   | Frank Warmerdam, [email protected]
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | Geospatial Programmer for Rent

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