# Tag Info

Accepted

### Why do we need 4 points for homography but 7/8 points for fundamental matrix calculation?

It is because in the case of fundamental matrix, each correspondence point relates to only one constraint(i.e it maps a point to a line in other image). Hence 8 correspondence points are required. ...

### Apply Low Pass (Smoothing) Filter on a Set of Matrices and Reject Outliers

I would build a tensor of those matrices and use low rank or some thresholding methods on it. You may have a look for Tensor SVD.
Accepted

### Apply Low Pass (Smoothing) Filter on a Set of Matrices and Reject Outliers

The method used was a parametric representation of the matrix $H$. For intuition, think of rotation matrix in $\mathbb{R}^{2}$, namely $H \in \mathbb{R}^{2 \times 2}$. Since we have series of ...

### Step by Step Camera Pose Estimation for Visual Tracking and Planar Markers

While explaining the two-dimensional case very well, the answer proposed by Jav_Rock does not provide a valid solution for camera poses in three-dimensional space. Note that for this problem multiple ...

### Finding Homography Matrix Using Lines

I am not aware of any library which works directly on lines. A by pass would be, that given 2 line, you'd use a finites sample of point on the lines to calculate the Homography. To derive the ...
1 vote

1 vote
Accepted

### How are the scaling parameters included (extracted from) an essential matrix?

The Essential matrix is defined only up to scale, so you cannot extract scale from it. In other words, if you multiply $t$ and all the 3D world points in your scene by a constant factor, the essential ...
1 vote

### Obtain motion between image features by means of the homography matrix

First, calibrate your intrinsics: The focal lengths and the principal point. Homography is not really a rigid transformation and rather a mapping of a plane onto another one. What you really need is a ...

Only top scored, non community-wiki answers of a minimum length are eligible