[Gdal-dev] ArcView binary raster support

[Frank Warmerdam]

Matt Wilkie wrote:
> Hi Vincent and interested coders,
> 
>> Would it be possible to add support to gdal for native ArcView raster
>>  files, including other datatypes than simple ints, and (basic) 
>> projection support?
> ...
>> BTW I send this message to the list rather than directly to Frank 
>> because maybe others are interested too and willing to share the cost
>> :-)
> 
> I think the ESRI format most likely to be recognised and utilised across
> the widest range of versions of ArcView & ArcGIS is ArcInfo GRID (the 
> 'aig' driver to gdal).
> 
> I'm not in a position to offer sharing of costs but I can certainly 
> provide GRID rasters across the range of int types and projections for 
> anyone who is interested in developing an AIG write driver for gdal and 
> needs sample data.

Vincent / Matt,

I imagine Arc/Info Binary Grids are the most natural way to provide
raster support for ArcView.  Unfortunately, a fairly valiant effort on
my part to implement write support for this format a few years ago failed.
The format is undocumented, and while I was able to deduce enough information
about it to read it effectively, I was never able to write valid files.  I
am not terribly inclined to revisit this issue, though someone keen could
start from the existing file format definition (and perhaps I have some code)
and try to implement it.

Another format that is fairly well supported by ArcView is the .HDR labelled
BIL.  I have done some improvements in recent months to this driver and
you may find it suitable for some purposes.  However, it does not seem
to be a very expressive way of describing the data type (float vs. integer
for instance) which can be a problem.

I am open to other advice on good ways of exporting raster data in a form
that is useful in ArcView.

As Vincent mentioned, things should be better with ArcGIS (and hopefully
getting better with each new version of ArcGIS).

Best regards,
-- 
---------------------------------------+--------------------------------------
I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | President OSGF, http://osgeo.org