deskew plugin

[Michael Thaler]

Hi,

I ported the deskew plugin from gimp to Krita (1.6). Deskew is a plugin to 
automatically rotate an image such that the text is straight. You can find 
more information about the gimp deskew plugin here: 
http://www.cubewano.org/gimp-deskew-plugin/

I don't know if it is currently allowed to check in code in Krita 1.6 so I put 
the plugin on my homepage for now: 
http://users.physik.tu-muenchen.de/mthaler/code/deskew.tar.gz
You can use the image from 
http://www.cubewano.org/gimp-deskew-plugin/attachment/wiki/Screenshots/bor-skewed.jpg 
to try it out.

Just copy it into the krita/plugins/filters directory, then do a make -f 
Makefile.cvs and ./configure --prefix=/usr/local --enable-debug=full (or 
whatever options you use). This should create the necessary makefiles in the 
deskew directory. cd there and just do make && make install. The plugin is 
under enhance->deskew.

It is basically a pretty straightforward port of the gimp plugin code (which 
is a port from some obscure tool). Right now it probably only works for RGB, 
but it uses the the rotate_visitor to rotate the layer. So that part is 
already colorspace independent. The only missing thing is to transform the 
src pixels to rgb before analyzing them. Also I don't know if the preview 
widget actually makes sense. I don't think the algorithm works with scaled 
down text anyway, if the original text is not rather large. What do you 
think?

Should I check this in the Krita 1.6 branch?

Greetings,
Michael