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> Date: Mon, 4 Feb 2013 00:46:53 -0800
> From: elmer cabekaziruronometu wix gmail com > To: gimp-user-list gnome org > Subject: Re: [Gimp-user] Unskewing images of flat rectangular objects in Gimp > > Øyvind Kolås <pippin gimp org> wrote: > > The perspective tool has an inverse mode, if you align the grid lines > > from the wireframe preview with the lines desired to become > > horizontal/vertical and then do the transform you should end up with a > > rectified version of the quadliteral. > > Thanks! That worked. The size and aspect ratio of the rectified > quadrilateral isn't always close to what I want it to be, though. Is > there a way to specify this before I do the perspective transform, or > do I just need to do it in 2 steps (correct perspective, and then > re-size)? This is certainly an issue - the perspective tool would really benefit from having an option to automatically preserve the x/y aspect ratio (much like scaling already does), though exactly how it would work mathematically I don't know. I've found that if you note the [1,1] and [2,2] numbers in the transformation matrix you can do a manual rescale using those values as your X and Y scalars and it really helps, but it's not exact since it doesn't take rotations into account. -- Stratadrake strata_ranger hotmail com -------------------- Numbers may not lie, but neither do they tell the whole truth. |