[Gdal-dev] Scaling rasters

[Frank Warmerdam]

Jose Luis Gomez Dans wrote:
> Hi! I have a raster with value between 1 and 100, and also 0s (these are
> NODATA). I want to set all the pixels with valid values (DN>=1) to a set
> value (let's call it Z), while leaving the rest at 0. I have tried
> gdal_translate -scale 1 100 Z Z, I get something which is half-way there: I
> get Z where Z should be, but (Z-1) where I should have 0. Apart from writing
> a little program that does this, can the gdal standard utility programs be
> used for this?
> 
> Thanks! jose

Jose,

I can't think of any way to accomplish this with the commandline utilities.
A small python script using Numeric and GDAL should be able to do the trick,
though I don't see anything too similar in the samples directory.

Best regards,
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