A little clarification is in order here I think.

A *.TFW (world file) is really an ESRI convention and should not be
confused with a standard GeoTiff file.  GeoTiff images have the
registration tags (control points, PCS code, etc.) built right into the
tiff file header itself, and that is what the MapBasic utility GEOREG.MBX
looks for in order to create the *.tab file for registering the image.  If
GEOREG.MBX does not find these tags (or valid ones) in the Tiff file
header, it throws an error as it is probably an invalid GeoTiff image
according to the standards given below in these URLs I've provided.
GEOREG.MBX does not use any ESRI *.TFW files.

For more info on geotiff's:

http://testdrive.mapinfo.com/techsupp/miprod.nsf/kbase_by_product/43838B82CBBF77D7852565A30063C76A

For more information on PCS (projection) codes used for GeoTiff
      Registration:
ftp://posc.org/pub/geodetics/

Numerous examples of GeoTiff images:
ftp://ftpmcmc.cr.usgs.gov/release/geotiff/images/pci/

Comprehensive resource link concerning GeoTiff:
http://home.earthlink.net/~ritter/geotiff/geotiff.html

Another brief explanation of the format spec.:
http://www.spot.com/spot/home/proser/geninfo/format/dimap/welcome.htm
*look at bottom of screen.

New URL for GeoTiff Information as of 6/1/99:
http://www.remotesensing.org/geotiff/geotiff.html

Worldreg, et al., are mapbasic, or generally VB utilities that look for a
separate *.TFW file associated with this tiff image, and then use that TFW
file's info to create a mapinfo *.tab file with registration information.

I found a geotiff examiner utility from Mentor Software that allows you to
view\modify a tiff file's registration tags, or a TFW files contents.  It
may be wort a look.
http://www.mentorsoftwareinc.com/freebie/freebies.htm

Regards,
-Bill


Mail List:owner-mapinfo-l
                                                  
 From:    "Robert Batenburg"                      
          <[EMAIL PROTECTED]> on 07/06/2000    
          12:07 PM AST                            
                                                  
                                                  
 To:      [EMAIL PROTECTED]              
                                                  
 cc:      [EMAIL PROTECTED]                       
                                                  
 Subject: (Document link: MapInfo -L and Co.)Re:  
          MI TFW to Tab                           
                                                  



David,

You can try WorldReg from Data Directions.  The freeware version
supports .TFW and can be found at:

http://members.aol.com/MapData/wrv3.html

(MapInfo also ships with a tool called GeoReg but it regularly responds
with "the specified file does not contain valid registration information"
so you may find WorldReg less frustrating!)

Rob.

Rob Batenburg
GIS & Data Management Specialist
Agriculture & Agri-Food Canada
Pacific Agri-Food Research Centre
Agassiz, British Columbia
[EMAIL PROTECTED]

>>> "David Thibault" <[EMAIL PROTECTED]> 07/06 5:59 am >>>
> Does someone know where i could get a mapbasic program that can read the
> georeference file (TFW)(or geotiff) without having to re-enter manually
all
> the reference coordinates of the image in MapInfo in order to produce the
> reference file (TAB).


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