[Gdal-dev] Re: Fwd: gdalwarp with change in projection for tiles then adjacent tiles overlap slightly with a black border at edge.

[Frank Warmerdam]

John Mitchell wrote:
> Frank,
> 
> Is their any plans on getting rid of the black border that you get when 
> using gdalwarp to reproject individual tiles which results in the black 
> border slightly overlapping the image of its adjacent reprojected tile?
> 
> If the above answer is no then how would I put in a request to gdal for 
> this capability.

John,

There are already mechanisms to handle this.  Either treating the black as
nodata, or running gdalwarp in such a way to generate an alpha channel so
that the extra pixels are recognizable as transparent.  So, I don't
anticipate any changes in gdalwarp unless I am missing your point.

There have been a few gdalwarp related questions on the list I'd intended
to get back to and try to answer but I'm pretty swamped and that hasn't
happened.  It would be nice to have a "gdalwarp tricks and tips" topic in
the wiki!

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | President OSGeo, http://osgeo.org