[gdal-dev] GDALComputeRasterMinMax and 'nodata value'.

[Frank Warmerdam]

Michele Sanges wrote:
> Hi,
> 
> why the function GDALComputeRasterMinMax() computes the two values
> taking in account also the 'nodata value'?
> 
> For example:
> 
> # gdalinfo E020N40.DEM
...
> Band 1 Block=4800x1 Type=UInt16, ColorInterp=Undefined
>   Min=-9999.000 Max=5825.000 
>   Minimum=-9999.000, Maximum=5825.000, Mean=-2347.600, StdDev=4873.500
>   NoData Value=-9999

Michele,

I believe these values are computed by the GDALRasterBand::ComputeStatistics()
method which appears to include nodata handling.  So I'm not exactly sure why
it isn't excluding -9999 properly.  Perhaps a round off issue?

Can you submit a ticket with a dataset demonstrating the issue? Hopefully
a small dataset?

Best regards,
-- 
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