[Gdal-dev] arcinfo grid gotcha

[Matt Wilkie]

Norman Vine wrote:

 > Try adding the ArcInfo bin directory to your path or copy
 >   avbase.dll
 >   avfeat.dll
 >   avgridio.dll
 > from the arcinfo bin directory into a directory on your path

Thanks Norman but that is the opposite of what I want (thanks for 
itemising exactly which dlls are needed; I can use that). AIG is 
superior as it correctly reads and transfers the projection as well as 
the numeric type while GIO does not.

Frank Warmerdam wrote:

> Users can set the GDAL_SKIP environment variable with a list of space
> seperated driver names that they wish to not be used.
...
> set GDAL_SKIP="GIO"

thanks Frank, I can work with that.  I note that this disables both read 
and write with the specified drivers.  Not a problem for me currently as 
  I don't need both at the same time very often.

Actually, now that I think about it some more, is there any reason to 
use GIO for reading grids at all? Ideally AIG would be used for reading 
AI binary grids and GIO for writing AI binary grids.

Suggestion: allow explicit commandline options to override environment 
setting. For example:

	$ export GDAL_SKIP=GIO
	$ gdal_translate -of GIO inputimg.tif outputgrid

would work.

----
The link to http://www.remotesensing.org/gdal/frmt_various.html#GIO from 
http://www.remotesensing.org/gdal/formats_list.html "ArcInfo Binary Grid 
(GIO)" is broken. That target section does not exist. It does exist in 
my local html file of the same name for v1.1.8 though.


cheers,

-- 
matt wilkie
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