qgis - How to generalize and vectorize a LandUseClassification raster file?

I want to vectorize that rasterfile with its 6 landuse classes. The classification is very noisy and have to be generalized before.

The result should be a polygone vector file.

I use SAGA, (GRASS) and QGIS.

Answer

To simplify the raster it might be worth looking at gdal_sieve, it's available under the "Raster" menu. See: http://www.gdal.org/gdal_sieve.html

N.