Panoramic Mosaic Stitching
CSE 455: Computer Vision
Project 2 Artifact
Antonius Harijanto and Michael Hotan
We have one key difference for our Panoramic procedure. We use our images clockwise relative to perspective point. We had to renumber our images in reverse order compared to the order taken by the solution binary. Because of this, we placed a set of the test panoramic images but in reverse order. We also spoke to Avanish about this slight modification and he said it would be fine as long as we provide the images in reverse order.
We have tested our programs with different image sets including the given image set and everything works out well.
On some of our image sets, we get 0.00, 0.00 as the x and y feature alignment coordinate. When this happens increasing the RANSAC threshold value fixes it. The fact that the same thing doesn't happen so often with image sets taken with a tripod makes sense because the displacement between images is bigger when we take them without a tripod. And to tolerate this we need to increase the RANSAC threshold value.
Test sequence
Note that the image is a little different than what the solution binary generates. The reason is because we proccess the images in a clockwise manner while the solution goes the other way around.
Sequence with Kaiden panorama head
SSD ratio matching, RANSAC threshold = 2.
Sequence taken by hand
SSD ratio matching, RANSAC threshold = 4.
Observe the black cutoff on the right part of the panorama. Mike intentionally move the camera position when he took the part with black cutoff. He wanted to see the resulting panorama with such pictures. It turned out to be pretty great!
ROC comparison of our code vs. SIFT
The area under the ROC curve is the probablity of a randomly picked match to be a true match. In other words, among all the matches, the probability that a match is a ground truth is the area under the curve.
As expected, the state-of-the-art feature detection algorithm, SIFT, peforms better compared to the relatively simpler harris corner detection that we implemented for this project. Ratio test also performs better compared than regular SSD because it reduces the number of ambiguous matches.