On Tue, Feb 14, 2012 at 6:55 AM, kfj <[email protected]> wrote: > > > On 14 Feb., 18:25, Dan <[email protected]> wrote: >> in the software that creates the panorama > > The code which does the transformations is in libpano. First you have > to get a checkout of the code from their repository. Then you have to > look into the file math.c. The routines from where you can find your > way down are 'execute_stack' and 'execute_stack_new'. > > The transform is a rather complicated sequence of separate partial > transforms, including translations, rotations and more involved stuff. > These are modelled as individual functions which are put onto a stack, > which is, later on, executed for every target pixel in the warped > image. The execution of the transformation stack is done inside the > warping routine, and once the source location needed for the target > pixel has been determined, it's interpolated from the source image and > written to the target. Then the same is done for the next target pixel > and so on. I wish there was proper documentation for this - I have had > to work it out from the sources myself. If you want to just play with > the transform and not dig into the C code, you can use the utility > program pano_trafo which comes with hugin, and if you have a python- > enabled hugin, you can use the transforms in python as well.
The only thing that I would add to Kay detailed response is that the equirectangular is a very special type of projection in libpano. It is sort of the intermediary projection between fisheye or rectilinear and most projections. This is partially because it has the property x = \lamba and y = \phi --dmg > > 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] > For more options, visit this group at http://groups.google.com/group/hugin-ptx -- --dmg --- Daniel M. German http://turingmachine.org -- 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
