[gdal-dev] gdalbuildvrt

[Aníbal Pacheco]

On 02/03/2011 04:59 PM, Frank Warmerdam wrote:
> On 11-02-03 01:30 PM, Aníbal Pacheco wrote:
>> Hi, I'm using gdalbuildvrt to produce a virtual raster layer which can
>> then
>> used in Mapnik and its ogcserver(WMS), everything works except that
>> the result
>> image is black & white and with a very poor resolution. The 2 source
>> tif files
>> used in this test were both colored with a good resolution. Any ideas?
>
>
> Aníbal,
>
> I would suggest examining the resulting vrt to see if there is anything
> odd about it. Start with gdalinfo to see if it's resolution seems
> reasonable
> and if in fact it is 3 bands. You might want to run "gdalinfo -stats
> xx.vrt"
> to get band statistics just to verify that the bands are radiometrically
> distinct. Also, check that the band pixel type is reasonable - the same
> as the source files.
>
> If that all looks ok, then perhaps visually examine the VRT with something
> like QGIS.
>
> After that it comes down to talking to Mapnik people about why there are
> problems.
>
> Best regards,


I think there is something wrong with the vrt because QGis does not find 
the 3rd band, here[0] is a screenshot to help. thanks

[0] http://imgur.com/OHnFg