Using homographies, we change the perspective of already taken images.
A homography can be used to transform a tilted image into a head-on version. Just define some points on the image, define the target as a rectangle, and have the transformation match those points up
![]() Memorial Glade |
![]() East Asian Library |
![]() Source Rectangle |
![]() Target Rectangle |
![]() Professor Efros's Door |
![]() Meme |
![]() Failure Case |
![]() Squares too small |
We can also transform one image into the perspective of another. Then we can stitch the images together using some method previously learned to create a mosaic or panorama.
![]() ... |
![]() ... |
![]() Beach |
![]() ... |
![]() ... |
![]() Mount Tam |
![]() ... |
![]() ... |
![]() Mount Tam |
Today I learned it's surprisingly annoying to define correspondences in landscape images, even by hand, since a lot of the features are rounded and getting a perfect selection is challenging. Even the slightest error can cause signficant distortions, unless you define way too many points.