[gdal-dev] gdal_fillnodata smoothing water for a DEM

[Ivan Price]

Thanks Matt

my problem is that this operation needs to be performed over a very wide area, comprised of many images with many water bodies, so it needs to be automatic.

My plan is to write something in python that:

- generates vector polys from original NODATA pixel areas (greater than a given area)
- performs the raster interpolation using fillnodata (fills lakes)
- then loops through each vector (water) feature:
  - creates a raster mask of this feature
  - calculates the average elevation for the water feature
  - writes that value back over the same data, 
  - loops next vector feature

our data is fairly good in that the water/shoreline doesn't vary much, so i'm expecting ther'l be no cliff effects as you experienced.

cheers for your input!

-i


-----Message d'origine-----
De : Matt Wilkie [mailto:matt.wilkie at gov.yk.ca] 
Envoyé : Tuesday, 27 September 2011 7:48 PM
À : Ivan Price
Cc : gdal-dev at lists.osgeo.org
Objet : Re: [gdal-dev] gdal_fillnodata smoothing water for a DEM

On September-27-11 9:50:39 AM, Matt Wilkie wrote:
> Here is an excellent article on editing elevation models using photo 
> tools by Tom Patterson of the US National Park Service:
> http://www.shadedrelief.com/dem/dem.html

If this appears to be out of context, that's because it is. ;-) It's an addendum to a longer message with some attached images which is still waiting in the moderation queue.

matt wilkie
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