[gdal-dev] Closing disconnected contours

[Chaitanya kumar CH]

zeta,

Are the lines in topo.tif contour lines? How did you generate them?


On Tue, Feb 26, 2013 at 12:20 AM, zeta <otrov at hush.ai> wrote:

> Chaitanya kumar CH wrote:
> >
> >zeta,
> >
> >The gaps are likely caused by pixels with no data. A simple method is to
> >run gdal_fillnodata.py on the original raster and then create the
> contours.
> >
> >http://www.gdal.org/gdal_fillnodata.html
>
> Thanks Chaitanya,
>
> that's excellent news, as I previously searched for algorithms about curve
> reconstruction, and none seemed easy for implementation. I was driven by
> approach using Delaunay Triangulation,  referenced to Amenta "The crust and
> the beta -skeleton: Combinatorial curve reconstruction" and plastically
>  explained i.e. here:
> http://valis.cs.uiuc.edu/~sariel/research/CG/applets/Crust/Crust.html but
> I thought to look for shortcut if possible, without reinventing
> implementation.
>
> I tried the script, and I get some gaps filled, but most aren't. I used
> -md parameter of 20px, but changed that value from 10 to 300 without
> significant improvement. Then I used mask file, which I assume works as in
> OpenCV Inpaint function, by using mask as a helper for gap detection, but
> without success.
>
> I'm attaching example image, and mask image, which I used to test the
> script, in a hope that someone can tell me if better results are possible.
>
> Thanks




-- 
Best regards,
Chaitanya kumar CH.

+91-9494447584
17.2416N 80.1426E
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