[gdal-dev] reading Arc/Info Binary Grid

[Frank Warmerdam]

Robert Denham wrote:
> 
> Frank,
> it appears there are two ways to specifiy the projection information
> for UTM here. The one you might be more familiar with looks like this:
> 
> f2 [site1biggrd2m]> cat prj.adf
> Projection UTM
> Zone 56
> Zunits NO
> Units METERS
> Spheroid AUSTRALIANNATIONAL
> Xshift 0.0000000000
> Yshift -10000000.0000000000
> Parameters

Robert,

I have added support for using the Yshift to detect UTM in the
southern hemisphere. 

> This contain no parameters, and zone information etc is referenced
> directly. The other:
> 
> > > f2 [64676964grd1l]> cat prj.adf
> > > PROJECTION UTM
> > > UNITS meters
> > > SPHEROID WGS84
> > > DATUM WGS84
> > > PARAMETERS
> > > 153 0 0
> > > -40 0 0
> is actually the result of exporting an imagine .img file to a grid. It
> seems that enough information is there to set the zone and offset ok (for
> example the central meridian of zone 56 is 153, and presumably -40 is
> equivalent to a y offset of -10000000.

I have added support for this formulation as well. I am assuming that any
negative value for the second parameter indicates southern hemisphere, and
otherwise using northern hemisphere. 

Best regards,

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I set the clouds in motion - turn up | Frank Warmerdam, warmerdam at p...
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and watch the world go round - Rush | Geospatial Programmer for Rent