Dear list,
Currently I try to classify aerial images (30cm resolution) in order to get a generalized vector landcover map. Since the SMAP results contain lots of small areas. I use r.neighbour (again and again) to filter those areas and then convert the results into vector format.
unfortunately those map still contains about 60000 polygons and most of them are smaller than maybe 50sqm. How is it possible to delete those polygons with different category values? I don't need them on the map?
I would like to dissolve them according to their area size and/or maybe their category value for example and put them to one of the larger neighbour areas. I tried already the -d parameter in the v.extract module established by Radim and Hamish (my last test was on 17.June from CVS) - thanks a lot for this help! - but this problem probably can't be solved with it.
I hope anyone has an idea to solve this, too ...
thanks a lot
Otto
I have added 'sides' option to v.to.db, so now it is becomming
SQL exercise.
Radim
On Friday 18 June 2004 13:15, Otto Dassau wrote:
Dear list,
Currently I try to classify aerial images (30cm resolution) in order to get
a generalized vector landcover map. Since the SMAP results contain lots of
small areas. I use r.neighbour (again and again) to filter those areas and
then convert the results into vector format.
unfortunately those map still contains about 60000 polygons and most of
them are smaller than maybe 50sqm. How is it possible to delete those
polygons with different category values? I don't need them on the map?
I would like to dissolve them according to their area size and/or maybe
their category value for example and put them to one of the larger
neighbour areas. I tried already the -d parameter in the v.extract module
established by Radim and Hamish (my last test was on 17.June from CVS) -
thanks a lot for this help! - but this problem probably can't be solved
with it.
I hope anyone has an idea to solve this, too ...
thanks a lot
Otto
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