So, I have a land use map that I need to digitize. The changes in the map is very fine so it will take a long time to manually digitize it. When I used the Raster > Conversion > Polygonize (Raster to Vector) function, the output shapefile is just black. I tried bands 1 to 4 but same result.
I also tried SAGA's Raster values to points and GRASS' r.to.vect but the result is the same: a black shapefile.
Can anyone help?