I re-added a straightening function the the calibrate_lens tool. Call it with a -w 1 flag.
It assumes that all lines that are taller than they are wide are vertical. Then it rotates these about the image centre such that the difference in their max/min x-coordinates is minimised, and returns the angle of rotation. It's very crude and I haven't really tested. Take a look in Straighten.cpp if you're interested. Cheers, Tim On 22 December 2010 10:44, kfj <[email protected]> wrote: > > > On 22 Dez., 04:16, Tom Sharpless <[email protected]> wrote: > > > Kay is right. There is no way software, just looking at an image, can > > tell which way is up. That requires outside information, either from > > a person, who can judge such things, or even better, from a sensor in > > the camera. > > Maybe intelligent guesswork could get it right in a reasonable number > of cases, though: > > - roll isn't excessive > - pitch isn't either > - there are vertical linear edges detectable in the image > > with these guesses assumed true (and specified as prerequisites for > the method to work), try > > - any detectable linear edges roughly parallel to assumed vertical are > candidates > - if a good number of these candidates are near paralel or can be > found to converge in a common point, they probably are vertical too > > The person who takes the photo doesn't just hold the camera out > randomly, particularly if the intent is to later make it into a > panorama, so the approach might work just like auto-levelling in hugin > works well with it's statistical approach if the images are > reasonable. Most photographers will make an effort to get their > verticals right, so it would only be a matter of fine-tuning the > result. If that fails or the prerequisites aren't met, it can still be > done manually. > > Kay > > -- > You received this message because you are subscribed to the Google Groups > "Hugin and other free panoramic software" group. > A list of frequently asked questions is available at: > http://wiki.panotools.org/Hugin_FAQ > To post to this group, send email to [email protected] > To unsubscribe from this group, send email to > [email protected]<hugin-ptx%[email protected]> > For more options, visit this group at > http://groups.google.com/group/hugin-ptx > -- You received this message because you are subscribed to the Google Groups "Hugin and other free panoramic software" group. A list of frequently asked questions is available at: http://wiki.panotools.org/Hugin_FAQ To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/hugin-ptx
