INDRIYATI ATMOSUKARTO
CSE576 PROJECT 2 - PANORAMIC MOSAIC STITCHING
THURSDAY, 28 APRIL 2005
Objective
Implement a system to combine a series of photographs
into a 360-degree panorama.
The system will automatically align the photographs by determining
their overlap and
relative positions and then blend the resulting photos into a single
seamless panorama.
Results
To see the panorama view you will need to use an absolute URL
and not just access the page locally, so to save trouble of uploading
the page somewhere you can also access it from my webpage at http://www.cs.washington.edu/homes/indria/project/CSE576project2.
1. Test sequence
360º
view

2. Sequence taken at Magnuson Park with Kaidan Head
Taken with Shani and Anna
The radial distortion parameters may not be absolutely
accurate because there seems to be some warping
distortion especially at the walkpath and the grass. I remember it
was a sunny day so not much exposure problem,
but unfortunately a windy day as well so some of the tree leaves
were moving as we were
taking pictures.
360º
view

3. Sequence taken at Magnuson Park with Kaidan Head
Taken with Shani and Anna
Same problem as above, the radial distortion
parameter may not be the most accurate parameters since I noticed
some distortion in the grass. But then again grass is kinda difficult
to match since it all looks the same.
360º
view

4. Sequence taken at University District with Kaidan Head
There was a car passing by right at that
last shot, I didn't see it. But overall it came out better than the
previous
two sequences. This time I made sure the camera was zoomed out, and it
was using manual mode to avoid
the same problem. Plus I avoided grassy patches all together :)
360º
view

5. Sequence taken at Gasworks Park with Kaidan Head with same person in
multiple frames
Mistake: I should have asked him to
stay put for more than one frame
which should reduce the ghosting effect, or
to stand in the middle of
the frame for at least one frame since the blending effect puts heavier
weight on middle pixels.
But what surprised me was this time the grass came out well.
360º
view

6. Hand-held sequence at Skagit Valley
Mistake: too many people
walking around so there are ghosting effects and problem in matching.
Not to mention the
red trolley was just passing by at that last 2 frame. Also I
think I moved my body instead of moving the camera so
the focal
length parameter is not accurate which might explain the huge black gap
at the bottom?
Well I literally didn't hold my hand steady so the
height where each frame was taken are all different and I could not
quite figure out the overlap in between each frame cause the sun was
shining so brightly making it really difficult
to see the LCD display. Another excuse is all tulips look roughly the
same so of course there will be mismatches.
I think if I crop that black bottom part it
would leave a better impression.
360º
view

There much better isn't it :)
360º
view

What worked well
For these test images
it seems the feathering blend did a pretty good job and I was quite
happy with the results. I used SIFT features for matching and
overall they match really well except maybe on grass patchess and
water.
What didn't work so well
Taking pictures while there are people moving inside, you will
end up seeing a lot of ghosting effect.
Extra credit
Taking picture of same person in multiple frames (Result 5)
Conclusion
- Take pictures on a non-windy sunny day
- Take the extra time to make sure the camera is straight (bubbles
are aligned etc), zoomed out, and manual mode
- Find a desserted place with not many moving objects
- If taking picture of same person in multiple frames, make sure
the person is at the center or take more than one frame to reduce
ghosting effect
- Hold you hand steady and rotate the camera not your body (if you
really insit on doing handheld sequence