[gdal-dev] GDAL Erdas LAN/GIS driver

[Frank Warmerdam]

Roger Bivand wrote:
> Hi,
> 
> The code for the LAN/GIS driver uses GDT_Int16 for Pixel type 2, rather 
> than GDT_UInt16. Is this justified? A user of rgdal has a case of 
> unsigned 16-bit data stored by "a forest landscape model", being treated 
> by the driver as signed. The header does not seem to have a 
> signed/unsigned flag. Is this a problem of ambiguity in use of a 
> (closed?) specification, or should the driver be using GDT_UInt16?
> 
> I'm asking on the list first, because this may be ambiguity, not a bug.

Roger,

The only specification information I have on the format does not indicate
whether 16bit values should be treated as signed or unsigned.  If you are
confident that it should be treated as unsigned file a ticket and we will
fix it - hopefully this won't just break it for someone else!

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