Another resurrected script. This script uses a path along the skewed horizon and rotates the image so that the horizon is straight.

Download the script here: http://registry.gimp.org/node/22910

The script is located in GIMP at <image> Layer > Auto rotate.

View the original, skewed image here.

After using the script and before cropping the image. You can see the originally drawn path at the horizon angle of the original image.



Image cropped.




Jolie has written an excellent tutorial that does the same thing. Be sure to check it out.
Fix a skewed horizon the professional way!

Is it used as a de-skew tool? I'm not sure of its use beyond that.

As far as I know, that's all it is used for, de-skewing. You could probably rotate something with it also.

One of the few really good things about paint shop pro was their de skew function, it worked a lot like this. I'll give it a try.