Howtosignalprocessing
- What is the difference between perspective and affine transformation?
- What is perspective transform?
- What is the difference between homography and fundamental matrix?
- What is a homographic transformation?
What is the difference between perspective and affine transformation?
Affine transformations can be thought of as a subset of all possible perspective transformations, aka homographies. The main functional difference between them is affine transformations always map parallel lines to parallel lines, while homographies can map parallel lines to intersecting lines, or vice-versa.
What is perspective transform?
Fundamentally, it is a transformation of a frame of reference that allows a more “democratic” way of perceiving and acting in the world. Perspective transformation implies not just a change of perception but action as well because it is not enough to see the world differently; one must act differently in it.
What is the difference between homography and fundamental matrix?
Whereas a homography relates coplanar image space points, the essential matrix relates any set of points in an image to points in another image taken by the same camera. Because the essential matrix is more generic than a homography it requires more points to calculate. findEssentialMat requires >= 5 points.
What is a homographic transformation?
Homography, also referred to as planar homography, is a transformation that is occurring between two planes. In other words, it is a mapping between two planar projections of an image. It is represented by a 3x3 transformation matrix in a homogenous coordinates space.
