Is there any tool that can help me with my problem?
I have polygons looking like this :
And what I want, is to simplify or gain convex boundary of such polygons.

I tried Simplify Polygon in ArcMap, Simplify Geometryin QGIS and v.clean in Grass using: snap lines/boundaries, remove small angles at nodes.
I tried these tools also on polygons converted to lines.
Some of these tools worked, but my layer was changed too much. I need something like inteligent convex boundary.
Do you have any ideas ?

v.cleandid you use this parametertool=rmarea? – Taras Mar 04 '19 at 11:06arcpy.da.UpdateCursorbut the generic nature of the question doesn't support the effort of writing an answer. – Vince Mar 04 '19 at 12:32