[Xastir] .tfw to .fdg conversion??

[Kirk Mefford]

At 11:21 PM 5/22/2003, Curt Mills, WE7U wrote:
>On Thu, 22 May 2003, Kirk Mefford wrote:
>
> > Since no one answered me on my last question I did some more digging.
>
>That means no-one knew the answer, or no-one has read it yet that does.
>
>
> > I have a rather large image I want to use a map that was created with a
> > ESRI worldfile ".tfw" file for the georeferencing information.  Xastir I
> > know doesn't support this format but does support Geotiff files with .fdg
> > data files.
>
>Yes.  It also supports images as long as they have associated ".geo"
>files and you have compiled in ImageMagick (most image formats) or
>XPM (XPM format images).

I am very aware of that.  That's why my first idea was to make a .geo data 
file for the image, hence my first question.  I know the format of .geo 
files and basically how they are made... I made a couple to experiment 
earlier from a tigermap image.

I've found it somewhat difficult to get the calculation just right to make 
the map line up with other maps though.  That's why I asked if there was an 
easy way to extract or decode the data from the worldfile data format 
either automatically or manually.  The worldfile data I have to the image 
in question is for the upper left and lower right pixel but I can't seem to 
understand how to pull a lat/lon from the worldfile data.