Hi, Try to localise the problem. Start for example by converting a small window (same you used with Mapnik) from the .vrt file into geotiff with gdal_translate. If the result is good then the problems is probably in how Mapnik treats .vrt. If GDAL makes odd result as well then the reason is probably in the .vrt file of something related to the originals. I can only say that I have used .vrt files for combining thousands of original images and results have been good both with GDAL tools and through Mapserver WMS and WCS services. I could also be good to start from the most simple case. Take two adjacent images and check them visually and with gdalinfo to see they are OK. Then make a .vrt from those two and see what happens.
-Jukka Rahkonen- -----Alkuperäinen viesti----- Lähettäjä: [email protected] puolesta: Aníbal Pacheco Lähetetty: su 30.1.2011 22:24 Vastaanottaja: [email protected] Aihe: Re: [Mapnik-users] gdal layer question Thanks, it works but the result is very strange, black and white images with very very poor quality On 01/30/2011 05:56 PM, Rahkonen Jukka wrote: > Hi, > > I would have a try with virtual raster (.vrt) by using gdalbuildvrt utility. > Mapserver does support .vrt also so you will be able to compare speed and > quality. > > -Jukka Rahkonen- > > > -----Alkuperäinen viesti----- > Lähettäjä: [email protected] puolesta: Aníbal Pacheco > Lähetetty: su 30.1.2011 19:52 > Vastaanottaja: [email protected] > Aihe: [Mapnik-users] gdal layer question > > Simple, I have a large amount of tif images (+100) > I want to define a layer using them, is that possible? > > The gdal datasource description[0] referes to a "gdal dataset" but in > the gdal utilities doc[1] seems to be no tool to build this "dataset". > > (I've tried using a shape layer built with gdaltindex like in mapserver > without luck) > > [0] http://trac.mapnik.org/wiki/XMLConfigReference#Datasource > [1] http://www.gdal.org/gdal_utilities.html > _______________________________________________ > Mapnik-users mailing list > [email protected] > https://lists.berlios.de/mailman/listinfo/mapnik-users > > _______________________________________________ Mapnik-users mailing list [email protected] https://lists.berlios.de/mailman/listinfo/mapnik-users _______________________________________________ Mapnik-users mailing list [email protected] https://lists.berlios.de/mailman/listinfo/mapnik-users
