Howtosignalprocessing
- How is homography calculated?
- What is a homography?
- Why do we need 4 points for homography?
- What is 2D homography?
How is homography calculated?
Thus, homography can be calculated using relative rotation and translation between two cameras.
What is a homography?
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.
Why do we need 4 points for homography?
In fact, we need at least 4 points, because the homography matrix has 8 free variables (each point contains and x and a y, for a total of 8 equations). To make the homography more stable, we can utilize more points and derive the least squares equation to solve the overdetermined system.
What is 2D homography?
Definition: A 2D homography is an invertible mapping h from P2 to itself. such that three points x1,x2,x3. lie on the same line if and only if. h(x1),h(x2),h(x3) do.
