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This refer to this post : Read Here

My goal is to select an area covering some points, but maintaining some space from points of border, like in the follow picture :

enter image description here

I think ST_Convexhull will do the job, but the border will touch the points in the edge. I need some "tolerance" increasing the area in some way.

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You could buffer the points and get the convex hull of that. Your illustration is more of a concave hull though, much more complicated. – blah238 Dec 1 '12 at 0:12
What if I create big circles around my points and do a ST_ConcaveHull ? This will make a "rubber" in circles that surround my points at the distance I need ... Can somebody explain me how can I do that in PostGIS ? – Magno C Dec 3 '12 at 10:43

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