[FWTools] fileexport option

[Frank Warmerdam]

On 11-01-16 11:54 PM, sethupathi balaji wrote:
> hi list
>
> Let me first extend my thanks for providing such a nice tools in FWtools 2.4.7
>
> I have bigtiff file of size 9 GB. I opened the file in fwtools and tried to
> export the tiff file in .pix format.
>
> i noticed a change of projection information when i exported tif to .pix as
> given below
>
> tif file parameters- UTM 43 N with WGS 84 &  False easting is 500000     False
> northing is 0
>
> .pix parameters   - UTM 43 S with WGS 84 & False easting is 500000     False
> northing is 10000000
>
> while other parameters like latitude of origin, central meridian, pixel size,
> origin remains the same
>
> what is the problem, i am using FWtools 2.4.7 for windows
>
>
> But when i work with images of size less than 2GB there is no such problem.

Balaji,

I skimmed the code and the logic to tranlate to PCI UTM coordinate
systems looks like:

     else if( EQUAL(pszProjection, SRS_PT_TRANSVERSE_MERCATOR) )
     {
         int bNorth;
         int nZone = GetUTMZone( &bNorth );

         if( nZone != 0 )
         {
             CPLPrintStringFill( szProj, "UTM", 16 );
             if( bNorth )
                 CPLPrintInt32( szProj + 5, nZone, 4 );
             else
                 CPLPrintInt32( szProj + 5, -nZone, 4 );
         }

This does not seem to have changed in recent memory.

/me tests translation...

Yikes, I was going to say it works fine for me, but I find exporting
a small UTM north file does, in at least some cases, get treated as a
UTM south file in the output.  I have created a ticket for this problem:

   http://trac.osgeo.org/gdal/ticket/3913

I can't think of a convenient work around for you to use.

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