[gdal-dev] substitute pixel values

[Hare, Trent]

Micheal,
   Check out repl_val.py in the GDAL/python samples.
http://svn.osgeo.org/gdal/trunk/gdal/swig/python/samples/

Changing it slightly you can do what you want.

original replace single value:
        scanline = numpy.choose( numpy.equal( scanline, inNoData),
                                      (scanline, outNoData) )

"Greater"
        scanline = numpy.choose( numpy.*greater*( scanline, inNoData),
                                       (scanline, outNoData) )

"Less"
        scanline = numpy.choose( numpy.*less*( scanline, inNoData),
                                       (scanline, outNoData) )


Does that help?

-Trent




On Wed, Jan 9, 2013 at 9:33 AM, Smith, Michael <Michael.Smith at maine.gov>wrote:

>  I have some DEMs that are created from lidar.  For reasons related to
> seeing currents and wind effect, we did not ask for the water to be
> flattened, but rather it shows waves.  This is cool, and what we wanted.
> BUT of course now we want to create a second set of DEMs with a  nice flat
> ocean.****
>
> ** **
>
> I have numerous pixels out in the ocean which are slightly less than 0.
> So how does one select out all pixels < 0 and substitute them with 0 with
> GDAL?  ****
>
> ** **
>
> ===============================
> *Michael Smith MS GISP*
> State GIS Manager, Maine Office of GIS
> State of Maine, Office of Information Technology
> michael.smith _at_ maine.gov
> 207-215-5530
>
> Board Member, Maine GeoLibrary
> Education Chair, Maine GIS Users Group
> State Rep, National States Geographic Information Council
> ****[image: icons]
>
> ***NOTE NEW ADDRESS***
>
> State House Station 145
> 51 Commerce Drive
> Augusta, ME 04333-0145
> 69o 47' 58.9"W  44o 21' 54.8"N****
>
> _______________________________________________
> gdal-dev mailing list
> gdal-dev at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/gdal-dev
>
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