[GRASSLIST:143] Re: NITF cropping question

[Allan Hollander]

Hi Julie,

Yes, GRASS should be able to import this image. GRASS handles raster
import and export through a library called GDAL (http://www.gdal.org/)
which supports the NITF format (see http://www.gdal.org/frmt_nitf.html).
The command to import the file in GRASS is r.in.gdal, which can be found
under the GIS Manager File > Import > Raster Map > Multiple formats using
GDAL. Once it is imported you can crop it by changing the map region to
your specific bounding box using g.region. In the GIS Manager g.region is 
found under Config > Region > Manage Region. In this input form, give the 
values for northern, southern, eastern, and western edges of the bounding 
box to crop to. Once it is cropped, you can export it using r.out.gdal 
(see File > Export > Raster Map > Multiple formats using GDAL).

Geotiff is the default export format for GDAL, but there are many others. 
To export it as MrSID however, you would need to purchase the MrSID 
encoding library from LizardTech.

You can also crop this image directly in GDAL and export it as a new
format without going through GRASS.  GDAL has a number of command-line 
utilities: the one that would accomplish this is called gdal_translate.

Best wishes,

Allan Hollander


On Wed, 15 Mar 2006, Julie Tittler wrote:

> I'm new to this software, and am still trying to get a successful install
> of the application. But, in the meantime, I was wondering if anyone can
> tell me how to do the following with the software:
> 
> I have an NITF satellite image which needs to be cropped to specific
> coordinates and saved as a new image, perhaps GeoTiff, or MrSids. Can this
> software do this, and if so, how? I did do some searching in the forum
> archives and failed to find anything specific to this. If someone could
> point me to the correct section of the documentation, or give me a series
> of steps for doing this, that would be great.
> 
> Thank you in advance for your suggestions.
> 
> Kindest Regards,
> Julie Tittler
> 

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