Creating word file

[Astrid Emde]

The discription of the wld-file you can find under:

http://mapserver.gis.umn.edu/doc44/raster-howto.html

Georeference with World Files

I hope that will help

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Georeference with World Files
World files are a simple mechanism for associating georeferencing (world
coordinates) information with raster files. ESRI was the first company
to propagate the use of world files, and they often used with TIFF
instead of embedding georeferencing information in the file itself.

The world file contents look like the following. The first coefficient
is the X pixel size. The second and third are rotational/shear
coefficients (and should normally be 0.0). The fourth is the Y pixel
size, normally negative indicating that Y decreases as you move down
from the top left origin. The final two values are the X and Y location
of the center of the top left pixel. This example is for an image with a
2m x 2m pixel size, and a top left origin at (356800E, 5767999N).

2
0.0000000000
0.0000000000
-2
356800.00
5767999.00

The name of the world file is based on the file it relates to. For
instance, the world file for aerial.tif might be aerial.tfw. Conventions
vary for appropriate endings, but with MapServer the extension .wld is
always OK for world files.


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Greetings Astrid

-------------------------------------
  Astrid Emde
  CCGIS GbR
  Siemensstraße 8
  53121 Bonn
  Germany
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   astrid.emde at ccgis.de
          www.ccgis.de
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  Tel.:      ++49 (0) 228 90826 19
  Fax.:      ++49 (0) 228 90826 11
  Zentrale:  ++49 (0) 228 90826 0
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Stephane Nicolas wrote:
> Hi,
>
>
>  I am trying to produce a world file (.tfw) for my tif image for use with
> php/map server. The image is x pixels by y pixels. I am unsure what the
> values would be for the first and 4 value.
>
>  ?
>
>  0
>
>  0
>
>  ?
>
>  90
>
>  -180
>
>  All the help on the internet has not made it clear to me.
>
>  I will appreciate a "non-mathematic" help....not that clever!
>
> s.
>