All Questions
Tagged with computer-vision camera
21
questions
1
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0
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127
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calibrating camera using 3d objects such as rubik's cube?
Hello all hope everyone is doing fine.
I have a vision related problem where I want to calibrate my camera using a 3d object such as rubik's cube with known dimensions. I have a cube with 60mm length, ...
- 11
0
votes
2
answers
55
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Fixing distortion in photographic reproductions
I am currently building a photographic setup which I intend to use to make reproductions of a large amount of transparencies(positive and negative film strips). As I will be using a fairly small (1&...
- 103
4
votes
3
answers
1k
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Detecting bullet holes using Python with camera or sensors
I am trying to build a system to detect bullet holes in paper. I've read many StackOverflow threads but not a single one satisfied me. Current methods, which I am using, are good but not perfect and ...
- 41
1
vote
0
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70
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How is focal length estimated?
There are a number of approaches to calibrate cameras. In this process you estimate the intrinsic parameters using a checkerboard of known size.
I'm confused on how the focal lengths are found. The ...
- 854
0
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1
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245
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Find camera pose by knowing triangle coordinates
I have this concrete problem where I know the 3 coordinates of a triangle $ABC$ in a $xyz$ frame reference and I need to estimate the position $P$ and direction $\vec{n_{p}}$ of a stationary camera ...
- 111
0
votes
1
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168
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Understanding legacy code: Algorithm to remove radial lens distortion
The method below to remove lens distortion from a camera was written more than ten years ago and I am trying to understand how the approximation works.
...
0
votes
1
answer
516
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Camera Pose Estimation from Vanishing Points
I want to estimate the pose of camera (Location and Orientation). Can I use Vanishing Points to get the location and orientation of the camera?
There is object in the image which I also know his size,...
- 3
-1
votes
1
answer
252
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Why reprojection error is minimized instead of triangulation error for bundle adjustment?
For bundle adjustment optmization why is reprojection error minimized instead of traingulation error or ray-to-3d point error? Disadvantage with reprojection error is: for perspective camera, its ...
2
votes
1
answer
558
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Stereo triangulation similar triangle derivation
I understand that the similar triangles are the red and blue triangles. I'm trying to understand where $T + x_r - x_l$ comes from. I understand we are trying to compute the length of the base of the ...
- 23
1
vote
2
answers
8k
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Camera calibration and extrinsic parameters for perspective transformation
I'm working in a photogrammetry camera and laser application where I need to measure a displacement in a specific plane, this is a quick diagram of the setup:
In order to get proper measurements I'm ...
- 137
0
votes
1
answer
320
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Pinhole camera model from houdini parameters
From a simulation with Houdini software I retrieved these parameters:
Camera position: -0.675839, 33.5945, 0.0318854
Camera Rotation: 0.0318854, 92.4693, 0.1
Focal Length: 52.5172 mm
Image size: 1920 ...
3
votes
0
answers
814
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Correct Fish Eye camera Radial Distortion and blurry effect at the image edges
There are a lot of questions regarding this topic ,but I am trying to get a more clear picture from these questions.
I am trying to calibrate a fish eye camera and I am using OpenCV omnidir class ...
- 131
1
vote
2
answers
322
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Estimate camera generalized velocity from consecutive frames
Let's suppose I have a camera which can move freely in 3D space and has 6 degrees of freedom. Is it possible to estimate the linear and angular velocity of the camera from 2 or more consecutive frames?...
- 141
5
votes
2
answers
3k
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How to estimate radial distortion from lens characteristics?
Is there a way to estimate the radial distortion coefficients without calibration, given the lens characteristics, such as its diameter and its focal length?
Typically for camera calibration a ...
- 5,101
3
votes
2
answers
6k
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Camera calibration using multiple images
I am trying to get the hang of camera calibration. For this purpose, I have mainly watched this lecture on youtube: Lecture 12: Camera Model by UCF CRCV. I believe that I understood the main ideas:
...
- 183