[ptx] RFC: "tube-panorama"

[Sebastian Nowozin]

Hi *,


my brother and me travelled some interesting road in Shanghai, that would make
a very nice picture as very long linear picture. Like photographing each side
of the road, complete as one very long picture. We thought and discussed a bit
about it and then end up at a different kind of panorama image, we called
"tube".

Here is some food for thought and questions how doable such kind of panorama
is... please discuss/reject/approve it freely :)



Three-dimensional "tube-panorama"

The idea is this: Instead of having a single point around which a sphere with
image information is constructed, one could have a "line", around which a
"tube" is constructed. The ends of the tube are half spheres. So, with a
viewer programm, one could do the usual viewing operations, plus travel on
this "line" forth and back.

The idea sounds neat, but there are some problems there. (obviously not
complete)


1. Recording the pictures

The ideal recording would be a 1-pixel 360 degree CCD slid at equal speed over
this line, recording all information. The 1-pixel lines are then used to form
the tube. This is the ideal world without any parallax effects, in reality
this has to be simulated through taking many pictures (maybe a video?). With
many objects in different depth there will be unavoidable parallax effects,
but the more pictures (video?) the less problems. The feature correlation
and/or motion detection for the pictures (to get equal-sized slides of the
tube) could be done automatically with SIFT.


2. Constructing the panorama

There would have to be a new projection type, that would have half-spheres on
both ends of the tube, and a cylinder/tube between the spheres. Besides that,
I see no obvious problems. One would have to mark where the tube starts and
ends, or this could maybe detected automatically. Each image would have to be
assigned a new coordinate: the position on the line (maybe just 0.0 to 1.0,
and maybe also automatically doable).


3. Viewing

Unfortunately it would require some slight modifications to the viewing
software to account and allow for sliding on the one-dimensional line.
Questions: Would the viewer recognize its a "tube" immediately? Can it look as
realistic as a normal spherical panorama does? How to linearly store the image
as .JPG to be able to view it statically, without viewer, too? (maybe as four
lines: two half-spheres, and two rows for the tube in length, each 180 degree)


Thanks for your thoughts :)


ciao,
Sebastian

-- 
nowozin at cs.tu-berlin.de --- http://user.cs.tu-berlin.de/~nowozin/