[SciPy-User] line/edge detection and output of coordinates.

Christopher Barker Chris.Barker@noaa....
Fri Apr 16 11:15:50 CDT 2010

Dharhas Pothina wrote:
> So for the GIS/GDAL suggestion are you talking about exporting the
> lines once I've used another technique to highlight the edges? Or
> will the Raster 2 Vector functions also help with the edge detection.

In GIS, the a common problem is create contour lines from a digital 
elevation model. In your case, you could think of the darkness of the 
pixels as an "elevation", and thus contouring it would create a vector 
outline of the dark pixels.

Another problem in GIS is taking a rater where each pixel value 
represents some scalr quantity, like land cover type, and to turn that 
into vector polygons -- that might actually be closer to what you need 
than contouring.

One trick is that your data are noisy -- hopefully appropriate smoothing 
will take care of that.

Now that I think about it, there are other contouring tools in python, 
one in Matplotlib, for instance, that might work.


Christopher Barker, Ph.D.

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