oups, Resending previous incomplete message
Sandor,
you are looking only at spikes. My algorithm presented in recent threads on
the talk list about Building Geometries detection will also detect regular
geometries that have any irregular edge ( a difference of more then 2 degrees
). It cannot distinguish valid irregular geometries, but they are in general a
small numbers, and most flagged buildings correspond to imprecise building
traces.
regular polygons- 90, 90, 90, 90
- 90, 270, 90, 90, 90, 90
- 120 * 6 (hexagon)- 135 * 8 (octagon)
refhttps://lists.openstreetmap.org/pipermail/talk/2018-August/081274.htmlhttps://lists.openstreetmap.org/pipermail/talk/2018-September/081392.html
Pierre
Pierre
Le jeudi 18 octobre 2018 09 h 15 min 53 s HAE, SandorS
a écrit :
Some days ago there was a question on an OSM forum whether such algorithm
exists and used by some of the OSM users. Honestly I even did not know that
such an issue exists and probably I am not alone. The reason to that is either
that the spiky configurations are hardly visible in maps or that robust users
handle them as a special case when process tiny outgrowths in their data
generalisation programs. A closer look at the issue has shown that the issue is
real and rather general. Spiky configurations exist on most of the area
borders, roads, roundabouts and so on, there is a huge number of them and
almost all are errors. To provide strong arguments about the former statement I
have made an algorithm, a simplified version of the tiny outgrowths detection
and removal, and applied the corresponding program to the OSM UK buildings. The
algorithm on a certain abstraction level, its use and the processing results
are described in details in an article here
https://drive.google.com/open?id=1MaLdnSnc454xKjn3eL95vDQKeoIW8zGU . There are
around 120K spiky buildings in OSM and out of these 2834 in the UK. In
addition, the paper presents many examples how the spiky buildings look before
and after the correction. Also, the paper contains links to the output data of
the demo/test processing and how these could be used for visual analyses. So,
if interested, enjoy the paper.
Regards, Sandor.
Sent from Mail for Windows 10
___
dev mailing list
d...@openstreetmap.org
https://lists.openstreetmap.org/listinfo/dev
___
talk mailing list
talk@openstreetmap.org
https://lists.openstreetmap.org/listinfo/talk