[Gdal-dev] geotiff nodata tag

[Frank Warmerdam]

On 10/7/05, Matt Wilkie <matt.wilkie at gov.yk.ca> wrote:
> Hi Folks,
>
> Frustratingly ESRI's ArcMap & Catalog  ignore the nodata value in
> geotiffs created by gdal (for 8bit greyscale at least, I don't know
> about RGBa). Is the nodata tag a specific gdal thing or is it part of
> the official GeoTIFF spec?

Matt,

It is specifically a GDAL extension to the GeoTIFF format.  I think the
only way ArcMap would recognise the nodata value would be if
an appopriately constructed Imagine .aux file was associated with it.

Best regards,
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