[Gdal-dev] Re: Angular units in GeoTiffs

[Brent Fraser]

Frank,

  Many thanks.  I can't connect to CVS (is it still cvs.maptools.org?), but
I guess I can wait for the nightly snapshot...

Brent


----- Original Message ----- 
From: "Frank Warmerdam" <warmerdam at pobox.com>
To: "Brent Fraser" <bfraser at geoanalytic.com>
Cc: "GDAL Dev" <gdal-dev at remotesensing.org>
Sent: Monday, October 18, 2004 3:13 PM
Subject: Re: Angular units in GeoTiffs


> Brent Fraser wrote:
> > Frank,
> >
> >   Is there any way to create a GeoTiff with the GeogAngularUnitsGeoKey
set
> > using gdalwarp?  I want to create LatLong geotiffs with the tag set to
> > Angular_Degree.  The GeoTiff spec doesn't say if there is any default
units
> > setting (maybe I missed it) and some applications don't like it when it
is
> > missing.
>
> Brent,
>
> In my not-so-humble opinion any software that doesn't assume degrees for
> unstated angular units is *trying* to make life difficult for users.
> Sometimes I wish I could bash software developes with a clue stick.  Of
course
> sometimes I could stand a good clue-whack or two.
>
> There is currently no way to force GDAL to write out this tag except to
> change the source.  You could, of course, accomplish this in an extra
> translation step using geotifcp but that would be tedious.
>
> Since you feel it would be helpful, I have modified the GDAL GeoTIFF
> driver in CVS to always emit GeogAngularUnitsGeoKey (as Angular_Degree).
> The change is now in CVS.
>
> 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    | Geospatial Programmer for Rent
>