I'm working in both ArcMap and Grass

I have a problem with the boundaries or the edges of my vectors. The vectors are a result of object segmentation (called classification) in Grass Gis. In Grass, an images is segmented and then I converted the raster into vector resulting in this: enter image description here

(this has been edited) And this is great however, the vector layer is framed. The 'frame' isn't a separate thing; those lines are polygon boundaries like any other on the interior. There is a square around the vector layer but because I have a little over thousand object segmentation rasters (which I'll turn into vectors) I need continuation, the frame must go.

enter image description here

Any thoughts on how to eliminate the frame? I'm open to Grass and ArcMap solutions. Maybe the solution is somewhere earlier in the process (the process being object classification to vector)

Edit: Here is an example of the intersection of 4 vector layers. enter image description here


It seems that you must use the Dissolve tool, based on a common attribute.


  • How would I use dissolve? I don't see any common attributes that I could use – Adam H Nov 4 '14 at 12:57
  • From the example you sent, it seems that you first need to do a bit of editing, not all the geometries fit together along the borders. Then whatever these geometries represent, they should have an attribute that they share (a land cover class, a code, a name..). If not, you should also create this common attribute. – Gianluca Franceschini Nov 4 '14 at 13:11
  • I think I understand. I guess I'm hoping for a more automatic way of doing this, because I have such a large datasaet – Adam H Nov 4 '14 at 13:21
  • If you don't have a common attribute to dissolve on then you will need to manually merge the neighbouring polygons one by one. – Jakub Sisak GeoGraphics Nov 4 '14 at 14:30
  • @AdamH This process is known as edge-matching. In theory the common attribute would be whatever defines the classes. When you vectorized the classed raster, there should be an attribute defining what class it came from. If they're all just polygons with no attributes, you may want to go back to that step. However I should point out a simple dissolve won't eliminate the 'frame' lines completely, as it's obvious from your image that classes aren't consistent from image to image. Some seem to match, but many don't (though it's hard to see with them all one color). – Chris W Nov 4 '14 at 19:09

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