[Gimp-developer] Blur tool darkens image?

[Jasper Schalken]

> You could have a look at the matrix convolution filter code. (Be warned
> there are some minor bugs concerning edge effects IIRC) but it will serve
> as an introduction to the different ways of treating edge data.

Is that "void convolve_region(...) {...}" in
/gimp/trunk/app/paint-funcs/paint-funcs.c?

It doesn't have many comments, so I'm not sure what its doing nor what
a convolution matrix is. I thought it would be along the lines of "for
each pixel in the region make it the average of all the pixels within
a certain radius". However, that gives a box blur and it may be
Gaussian instead.

I think I will just put this in a bug report and let someone who knows
have a look. :S