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I have .tiff files from aerial photography. I also have coordinates of the center of these pictures (northing, easting, height as well) stored in a excel table.

Is there a way to create .tfw world file from these information and, if so, what is the easiest?

PolyGeo
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hotigeftas
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  • A .tfw can apply a Translation, Scale and Rotation to am image. Most modern software create geotiff. This means the tfw information is inside the tif. You can manually georeference an image, creating a tfw, then edit it for each .tif. – klewis Jan 29 '18 at 16:51

1 Answers1

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From Wikipedia World file, with a real world file the generic meaning of the six parameters are

3.0384141414141403  A: x-component of the pixel width (x-scale)  
0                   D: y-component of the pixel width (y-skew)
0                   B: x-component of the pixel height (x-skew)
-3.0384143049932475 E: y-component of the pixel height (y-scale), typically negative
249090.9532070707   C: x-coordinate of the center of the upper left pixel 
142689.2657928475   F: y-coordinate of the center of the upper left pixel

in a simple way, if you know the size of the .tiff file (width and height) you can compute the A,E,C,F parameters, but not D and B (usually 0, no rotation). 

width, heigth = (990,741)
xul,yul = ( 249089.434, 142690.785) ->  coordinates of the upper left corner
xlr,ylr =  ( 252097.464, 140439.320) -> coordinates of the lower rigth corner  
A = (xlr-xul)/width  ->  3.0384141414141403
E = (ylr-yul)/height -> -3.0384143049932475
center of the upper left pixel 
C = xul + (A * .5)    -> 249090.9532070707
F = yul + (E * .5)    -> 142689.2657928475

But formally, you need to compute a six-parameter affine transformation

gene
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