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



Hi Shao:

In order to post, you must sign up for this email list at

  
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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
>