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alt textHello,

When I make contour lines of mountainous areas, I get some anomalies in the contour lines. At places where the lines are very close, I get polygons. In attachment [1] you will find such a .osm-file.

What is the reason of this anomaly, and how can I solve it?

I make contour lines with srtm2osm (OS: Ubuntu 11.04). In order to make a .osm-file, I use following command (with variables): mono Srtm2Osm.exe -bounds1 $ZL $WL $NL $OL -step $ele_mi -cat $ele_ma $ele_me

Thanks in advance.

asked 30 Oct '11, 12:17

Peter's gravatar image

accept rate: 0%

edited 30 Oct '11, 12:19

These are "voids" in the SRTM data - areas where there are no heights recorded in the SRTM data source.

There are a few void-filling utilities available, or you can find pre-processed SRTM data that has the voids filled in. Please note that many popular sources of void-filled SRTM data, including CGIAR and Viewfinder Panorama, are distributed under licenses that are incompatible with the OSM license.

permanent link

answered 31 Oct '11, 09:58

Andy%20Allan's gravatar image

Andy Allan
accept rate: 28%

Is there any worldwide better-than-srtm source available that has a compatible license ? If so, it could really do with some promotion, because these "srtm bugs" come back way too often (especially since they happen at high altitudes, which is often the areas you're interested in when you're interested in terrain).

(01 Nov '11, 11:31) Vincent de P... ♦

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question asked: 30 Oct '11, 12:17

question was seen: 4,313 times

last updated: 01 Nov '11, 11:31

NOTICE: is no longer in use from 1st March 2024. Please use the OpenStreetMap Community Forum