Hi, I have a vector map that has some narrow features (boat jettys etc) that I wish to smooth out. Can anyone suggest a method of achieving this please? I have tried several of the algorithims in v.generalise without success.
One of the problems I am experiencing is that small details seem to be treated similarly to large scale detail.
See links to example using snakes method.
Map prior to filtering...
<img src="http://osgeo-org.1803224.n2.nabble.com/file/n6873002/grass_test2_input.jpg" border="0" alt="map prior to filtering"/>
Map after filtering...
<img src="http://osgeo-org.1803224.n2.nabble.com/file/n6873002/grass_test2_filtered.jpg" border="0" alt="map after filtering"/>
<img src="http://osgeo-org.1803224.n2.nabble.com/file/n6873002/grass_test2_both.jpg" border="0" alt="map composite"/>
At the bottom-left of the map I have small spikes that I want smoothed over. They have been smoothed out reasonably well but the large spike has been converted into a short fat spike. I.e. it has been reduced in size by around the same percentage as the small ones. Also at the top-right of the map, a huge area of land has been chopped off.
Its as if the smoothing algorithm didnt take account of scale but just consider a number of vertices each side of the point and apply the filter without considering how far apart in metres the points are.
What I'm looking for is a way to smooth out the small detail especially small spikes, but not chop out big areas of land at larger scales.
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View this message in context: <a href="http://osgeo-org.1803224.n2.nabble.com/Smoothing-algorithim-to-remove-small-spikes-tp6873002p6873002.html">Smoothing algorithim to remove small spikes</a><br/>
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