[Geotiff] GeoTIFFs in ArcGIS 10

[Frank Warmerdam]

On 11-04-07 09:18 PM, Max Martinez wrote:
> April,
>
> There are at least two possibilities.
>
> First, the mask could be a whole other image in the TIFF file. This image would
> have a NewSubfileType tag value with the second bit turned on. You could
> disable this bit (then the mask image would either be ignored or treated as
> another image in the dataset) or you could remove the whole mask image by
> relinking the IFD chain without including the mask IFD.
>
> The other possibility is that the mask is an additional sample included with
> the 4 band image (so the image has actually 5 samples). In this case the
> ExtraSamples tag would likely have a value of 2 for “Unassociated alpha data”
> for the sample representing the mask. If you changed this value to 0, the mask
> would possibly be treated as another band and you might then be able to avoid
> displaying it.

April,

I would add that it would be helpful to see a report on the contents of the
file from the tiffinfo utility.  I believe it is available as part of
the FWTools for windows kit at:

   http://fwtools.maptools.org/

If you install the software, then launch the FWTools shell and enter a
command like:

   tiffinfo C:\path\to\your.tif > C:\path\to\your.txt

Then send the .txt file to the list.  That will give more concrete
information on how the file is setup.

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
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