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0
votes
1answer
43 views

removing spurious lines in raster before or after vector conversion?

I'm looking for a feature/function in either python opencv/ndimage/gdal/etc. or qgis/saga/grass that will help clean up a skeletonized image that I'd like to vectorize into a shapefile of ...
1
vote
2answers
50 views

how to get a low level road network from openstreetmap data?

I've extracted the road network of a city from openstreetmaps (filetype: osm). One part of the road networks look like this: However, there are too many details in this data. I'd like to represent ...
3
votes
1answer
3k views

Create centreline from a polygon

I am working on a project to create a centerline from a polygon automatically. The user select a polygon and click a button, the centerline will create for him. I have tried the build-in function ...
17
votes
3answers
3k views

Find tunnel 'center line'?

I have some map files consisting of 'polylines' (each line is just a list of vertices) representing tunnels, and I want to try and find the tunnel 'center line' (shown, roughly, in red below). I've ...
11
votes
4answers
2k views

Simplifying polygons to linestring

I would like to simplify some polygons that represent rivers into linestrings. I assume that holes in polygons can be omitted. Anybody has some good idea how to simply do it? It would be nice, if it ...