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boundary and pointsI have a point cloud and need to process a very detailed boundary around the outer points. Is there a tool in QGIS? Convex hull is not detailed enough.

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  • What do you mean by 'detailed enough'? Could you edit your post to share a sketch/diagram of what you are looking for? Also see this question.
    – Simbamangu
    Jul 29, 2015 at 8:48
  • I the pic you see the points and a hand drawn boundary.
    – Pimpel
    Jul 29, 2015 at 8:56

2 Answers 2

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In QGIS, many of the really good tools are in the processing toolbox; you need 'concave hull':

Try it with different threshold values for different levels of detail:

Finally, add a 10% buffer around the outside to make it resemble the sketch you provided:

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  • And then buffer the result to get the boundary line to look more like the OP's illustration.
    – user23715
    Jul 29, 2015 at 17:00
  • Good point, could make it match perfectly!
    – Simbamangu
    Jul 29, 2015 at 17:25
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Try Concave hull, What are Definition, Algorithms and Practical Solutions for Concave Hull?

Concave hull has a smaller area, and most of implementations allows you to tune how small and precise resulting polygon should be.

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