[Qgis-user] Rasters alpha channel black instead of transparent

[Alister Hood]

Hi,
This sounds like http://hub.qgis.org/issues/2491

> Date: Tue, 30 Aug 2011 02:38:30 -0700 (PDT)
> From: Pedro Ven?ncio <pedrongvenancio at yahoo.com>
> Subject: [Qgis-user] Rasters alpha channel black instead of
> 	transparent
> To: "qgis-user at lists.osgeo.org" <qgis-user at lists.osgeo.org>
> Message-ID:
> 	<1314697110.55042.YahooMailNeo at web65605.mail.ac4.yahoo.com>
> Content-Type: text/plain; charset="iso-8859-1"
> 
> Hello everyone,
> 
> I was cutting some rasters in the same way I did several times in the
past,
> adding the alpha channel to ensure transparency:
> 
> gdalwarp -of GTiff -r lanczos -dstalpha -cutline shapefile.shp
raster_input.tif
> raster_output.tif
> 
> However, now the area that would appear transparent, is shown in black
on QGIS
> 1.7 (and 1.8 dev), as you can see in the picture attached.
> 
> I've tried other software and it open the image with transparency in
these
> areas.
> Images that I've cut in the past and opened correctly in QGIS, now are
black
> instead of transparent.
> 
> Why is this happening? It is an option that can be changed?
> 
> Thanks!
> 
> Best regards,
> Pedro Venbncio
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