[Gdal-dev] looking for NoData compatibility with ESRI

[Frank Warmerdam]

Mark Phillips wrote:
> I'd like to use GDAL to write raster files containing a NoData value, in 
> a binary format that can be recognized by ESRI software (ArcMap, etc).  
> I've tried several experiments and haven't come up with anything that 
> works yet.  Geotiff seemed like an obvious choice, but apparently ESRI 
> uses a different convention from GDAL in geotiffs for storing the NoData 
> value.  I also tried ERDAS Imagine format, but it seems that GDAL can't 
> write the NoData value in an HFA file.
> 
> It doesn't matter to me which format it is --- I just need support for 
> one band, georeferencing, and a NoData value, in a format that I can 
> write with GDAL and then hand over to someone who uses ArcMap, so that 
> when they load the file, ArcMap correctly understands the georeferencing 
> and the NoData value.
> 
> I think it will work with AAIGrid (ESRI's ascii grid format), but it is 
> huge.  Does anyone know if it is possible with one of the binary formats?

Mark,

I'm sorry, but I can't think of any obvious (efficient) raster format that
you can transport nodata values in from GDAL to older versions of ArcGIS.

The most recent versions should recognise the GDAL nodata tag in GeoTIFF
but that doesn't help with older ones.

I think I have contributed code sitting in Trac for implementing nodata
support in the HFA driver but I don't think I've integrated it yet.

Best regards,
-- 
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