I am confounded by a lack of a good test case. So here is an image
that I suggest we should use to test our "versions" of Panini.
http://turingmachine.org/~dmg/temp/equirectangular.jpg
It is 3000x1500 pixels. I understand the geometry of this building
well, and there are only straight lines in it, with only 90 degrees
angles. the sides of the staircase run parallel to the side walls. The
far away walls and the back walls are all orthogonal. The area where
the tripod was placed is below a lower ceiling (appears very curve in
the image).
Here is my version of Panini: it is 226 x 123 degrees field of view. I
am projection from the equirectangular, to cylindrical, and then to
stereographic.
http://turingmachine.org/~dmg/temp/equiToCentralCylindricalToPanini.jpg
I really like it. The only area where it breaks down is on the roof of
the ceiling above the tripod.
Can all of you generate your versions, also at a width of 3000 pixels
from this image?
--daniel
http://turingmachine.org/~dmg/temp/equiMercatorialPanini.jpg
This is 360 degrees! where most of the lines are straight. It is
slightly compressed horizontally.
Use the doors as a reference point. It is almost as if I cut the wall
behind me, and unfolded the
room slightly.
The ceiling and the floor show some curveness.
--dmg
perfect symmetry, congratulations.
> Here is my version of Panini: it is 226 x 123 degrees field of view. I
> am projection from the equirectangular, to cylindrical, and then to
> stereographic.
>
> http://turingmachine.org/~dmg/temp/equiToCentralCylindricalToPanini.jpg
quite different from what I get with the lastest libpano/hugin from SVN:
http://www.photopla.net/hugin/equi2panini.jpg
230x179.9 degrees.
If I enter 226 HFOV in the stitcher panel, it returns 173.1 VFOV.
> I really like it.
I like yours better.
And I like a lot Max' Recti-Perspective.
Can you help me understand how to add projections to libpano13 -
specifically how to pass parameters such as the width/height of the
input image (in pixel) and its HFOV/VFOV? I've tried to peek around in
the code, but I still can't find the start and the end, only bits of it
(such as that what is in math.c). Needless to say that this is because I
am an analphabet and probably what I look for is just under my nose.
Yuv
Thanks Tom, Max, Yuv,
ok, so the pannini projection (emphasis on the double n) is going to be the
one created going from sphere to central cylindrical to stereographic.
We have several variants of the pannini, depending on what middle
projection is used. The one I implemented originally in panotools is
the "equirectangular pannini". We could further derive from Max's idea
and call it
equirectangular perspective.
This means that we can compute this type of projections from any type of
cylindrical projection. It will be interesting to see what would Miller of it.
Every use is different, for this particular image I prefer the
equirectangular pannini more
than the pannini. What do others think?
I am going to try to implement it in panotools next.
--daniel
Me too, Daniel's equiToCentralCylindricalToPaniniCorrect.jpg is
identical to the results I get with my original mathmap script.
>> I think I finally go the original panini right:
>>
>> http://turingmachine.org/~dmg/temp/equiToCentralCylindricalToPaniniCorrect.jpg
>>
>> it looks very close to your 1:2.
--
Bruno