Questions tagged [computer-vision]
Mathematical methods used in widely understood computer vision.
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Projection and depth map of a parabolic cylinder.
The problem:
I've been working on a project involving 3D graphics and camera projections, and I came across a problem that I need some help with.
I have a parabolic cylinder described by the equation $...
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Determinant of Jacobian of camera model
Consider a simple pinhole camera model as commonly used in computer vision:
$$
x_{\rm{pcs}} = f x_{\rm{ccs}} + p_x\\
y_{\rm{pcs}} = f y_{\rm{ccs}} + p_y
$$
where ccs represents the 3D camera ...
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Optimal rotation matrix
Context: I am trying to adapt the Rigid point set registration algorithm from Point Set Registration: Coherent Point Drift to include rotation information.
My problem can be stated as follows:
$\max_{...
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Curve Fitting and continuous identification of parameterized matrix eigenvector from unconnected data points
I need some help potentially applying machine learning or curve fitting techniques to a numerical linear algebra problem I am working on.
I have a parameterized symmetric matrix $M(s)$ whose ...
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Book Recommendation on Edge or Boundary Detection
I have recently being interested in the estimation of discontinuities or jumps from noisy signals or densities and spend some time reading "Image Processing and Jump Regression Analysis" by ...
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Confused about notations used in a Computer Vision paper
I was reading a computer vision paper for 3D reconstruction and was a bit confused by two notations: https://www.researchgate.net/publication/327805907_3D_Image_Reconstruction_from_Multi-...
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Computer Vison geometry: distance estimation of moving object from single fixed camera
I have a problem that I am still not sure if it's solvable. I have a system with a single fixed camera pointing to a fixed background (i.e., a wall). the distance between lens and background (at the ...
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"Histogram Equalization" Problem
Here we deal with the problem of Histogram Equalization.
Let $\Omega$ be the set of all pixels in an image, but you can just treat it as some arbitrary set in this case.
Let $f: \Omega \rightarrow \{0,...
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Fundamental matrix from camera matrices satisfying transpose property
Assume we are given a pair of calibrated cameras with projection matrices $\mathbf \Pi_0$ and $\mathbf \Pi_1$. From Hartley and Zisserman (pg 246), the fundamental matrix is
\begin{align}
\mathbf F
&...
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Are convex objects determined by their silhouettes?
Informally, the silhouette of a 3D shape is a viewpoint-dependent 2D projection of it. You might imagine looking at several silhouettes and attempting to construct the overall shape. My question is ...
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Need help in comparing two 3D point clouds
I am supposed to take 2 input point clouds and compare them to figure out if there are any differences in them in terms of lets say the location of the components, etc.
I thought of doing the feature ...
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Moving Eyespace/Camera around Globalspace
Im having a hard time understanding the concept of moving the eyespace/camera around the globalspace mathematically. Ive checked out a lot of videos/articles etc., but tbh at this point Im just ...
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How do projective transformation matrices work?
I've been working on a tool to turn photos of graphs into digital data (I know there are already tools out there, I wanted to understand the mechanism and I find learning by doing the easiest), but I ...
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calculating relative focal length based on a cylinder
I am trying to camera match a photo of a cylinder.
The photo is taken relatively straight, and I can get a rotation matrix for the camera based on the elipsis created by projecting the top circle.
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finding the radius of a cylinder based on camera position
Not entirely sure this is the right forum, but I'll give it a go.
I have a cylinder that is projected onto a 2d plane (3d world with a virtual camera).
What I want to figure out is, given a point on ...
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