[gdal-dev] crop a non-square subwindow?

[Frank Warmerdam]

On 11-03-10 05:07 PM, Wendell Turner wrote:
> Is there a way to force pixels outside of the cropping
> polygon to be 'not there', or transparent?  Is there a burn
> value that indicates that?

Wendell,

The -dstnodata parameter can be used to set the output nodata value.  I'm
not sure if it will properly mark that value as no data or not and whether
the end application honours nodata values in geotiff is ... variable.

Another approach is to use -dstalpha to add an alpha channel to the output.

Best regards,
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