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Re: netcdf-java post from address@hidden requires approval

Hi Shao:

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thank you

address@hidden wrote:
>
> Subject:
> process swath data by netCDF
> From:
> Yuanzheng Shao <address@hidden>
> Date:
> Thu, 12 Feb 2009 16:29:26 -0500
> To:
> address@hidden
>
> To:
> address@hidden
> CC:
> address@hidden
>
>
> Hi everyone,
> My aim is to extract the visible and infrared imagery from the DMSP/OLS
'smooth' data (with the format of OIS). Because the OIS belongs to swath data,
I think the current GridDatatype is unsuitable to process this format.
Definitely using the method "ucar.nc2.FileWriter.writeToFile", we can get the
corresponding netCDF file and we can view the visible and infrared imagery of
the netCDF file in NetCDF Tools.
>
> Then I want to write the geotiff with GeotiffWriter, but it failed because
the the axis in this file is unequally spacing (lat, lon). That's why the
GeotiffWriter throws an exception at GridCoordSystem.isRegularSpatial(), the
exception info was "Must have 1D x and y axes for  infraredImagery". So it
seems that I can not get the geotiff file from the generated netCDF file.
>
> So I changed to use gadl_translate tools to generate geotiff file. The good
news was I got the geotiff files and these files can be viewed correctly. The
bad news was that when I path this geotiff file with gdalinfo, it displayed
that this file was not a valid geotiff, without the Coordinate System.
>
> My question is how could extract different band from the swath data and write
them to geotiff? Does netCDF can perform this task? If I can not achieve this
aim only by netCDF, can anyone give me some suggestion?
> Maybe convert swath into grid is a effect method, but I have not found any
tools could do this.
>
> I also attached my sample data, which include the original OIS data, the
generated nc file by netCDF, and the gerated tif files by gdal_translate.
>
> Many thanks.
>
> Yuanzheng Shao
> CSISS, George Mason University
> 6301 Ivy Lane, Suite 620
> Greenbent, MD 20770
> TEL:571-480-3560
>