Mathieu, If 0 is a valid value at some locations of your raster, then you cannot use it as the nodata value. Use an alpha band instead for example by using -dstalpha instead of -dstnodata 0
Even > Hello, > > I crop a 3 band raster by a polygon with the following formula : > /gdalwarp -of GTiff -cutline polygon.shp -cl polygon input.tif output.tif > / > But pixels outside my polygon are assigned the 0 value. I'd like them to > have nodata > > If I put the -dstnodata 0 option : > /gdalwarp -of GTiff -cutline polygon.shp -cl polygon input.tif output.tif > -dstnodata 0/, all the pixels in each of the 3 bands that contain the 0 > value will be turned to nodata, even if they are contained in my polygon. > > Hence, 127 0 222 will become 127 nodata 222 > or 0 127 222 will become nodata 127 222 > > How to put the nodata value only outside my polygon ? > > Thanks a lot in advance ! > > Mathieu > > > > -- > View this message in context: > http://osgeo-org.1560.x6.nabble.com/Cropping-a-raster-by-a-polygon-only-nodata-outside-polygon-wanted-tp5181426.html > Sent from the GDAL - Dev mailing list archive at Nabble.com. > _______________________________________________ > gdal-dev mailing list > [email protected] > http://lists.osgeo.org/mailman/listinfo/gdal-dev > -- Spatialys - Geospatial professional services http://www.spatialys.com _______________________________________________ gdal-dev mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/gdal-dev
