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0 votes
0 answers
27 views

Image analysis with MATLAB: transforming an image taken at an angle back to direct view

I have a series of photographs taken at an angle, like this: What I would like to do is "straighten" these photographs into direct view: The above examples are taken from this Photoshop ...
Jonathan Huang's user avatar
0 votes
0 answers
118 views

How to do Perspective Transformation of Image

Suppose I have colmap camera poses, is it possible and how to obtain a new view of input image I (planar object) from a different viewpoint/camera pose using those poses? Colmap camera poses has ...
pkn's user avatar
  • 1
0 votes
0 answers
61 views

Align horizontal lines in projected view of matrix via opencv

I have two different matrices A (shape 5, 11) and B (shape 5, 2). I want to have a projected view of each of these matrices. Unfortunately, the horizontal lines that are separating different values, ...
bearyTheBear's user avatar
2 votes
1 answer
1k views

How to get rotation matrix from camera perspective

I have a camera mounted on a post which is looking at a specific field. I know the exact real world position of the camera C and I know the exact size and real world position of the field P1, P2, P3, ...
Dev_IL's user avatar
  • 282
0 votes
0 answers
116 views

How to turn these camera properties into standard calibration?

I have a product of a long closed company whose camera properties i need to figure out. I have the following info about the camera (e.g. FOV), and wonder how i turn this into standard camera ...
Diederick C. Niehorster's user avatar
2 votes
0 answers
308 views

OpenCV Perspective Transform with Reference Object

I'm a beginner with OpenCV, and I'm currently building out a project with a goal to find some relevant dimensions of a building (for now, just width and height in feet). See image below: I added a ...
dukedoug's user avatar
1 vote
1 answer
2k views

Given camera parameters, how do I find the transform from view space to pixel coordinates? What is wrong with my matrix?

For a specific image containing a known 3d obj model, I have the corresponding model matrix and the camera parameters fx,fy,cx,cy. Having applied the model matrix to the 3d model vertices, I want to ...
John Katsantas's user avatar
1 vote
1 answer
1k views

How to find a four point polygon approximation with OpenCV?

So I have a problem that requires me to get a perspective transform on a series of numbers. However, in order to get the four point transform, I need the correct points to send as parameters to the ...
Mateus Braga's user avatar
0 votes
0 answers
412 views

Estimate camera pose from 3 points with OpenCV

I have a straightforward (I guess) problem to solve with opencv: I have 3 non-colinear Points in the 3D system given in cm: Point A = Point(.., .., ..); Point B = Point(.., .., ..); Point C = Point(....
Duloren's user avatar
  • 2,652
0 votes
1 answer
386 views

Euclidean Distance of 2 points in opencv warped image

I have an image having a scale of cm/mm. I have warped it using cv2.getPerspectiveTransform and then I measure the Euclidean distance between 2 points of the scale. I know that warped images give ...
Saqib Naseeb's user avatar
0 votes
1 answer
287 views

Measuring objects in a photo taken by calibrated cameras, knowing the size of a reference object in the photo

I am writing a program that captures real time images from a scene by two calibrated cameras (so the internal parameters of the cameras are known to us). Using two view geometry, I can find the ...
stressed out's user avatar
0 votes
0 answers
276 views

estimation of the ground plane in pinhole camera model

I am trying to understand the pinhole camera model and the geometry behind some computer vision and camera calibration stuff that I am looking at. So, if I understand correctly, the pinhole camera ...
Luca's user avatar
  • 10.9k
1 vote
0 answers
291 views

calculating topdown/birds eye map from images with a sequence of poses

I am trying to build a topdown birds eye map of the road surfaces from a sequences of images, each which I know the ground truth poses. The data is from the KITTI dataset, of which I know the distance ...
avp's user avatar
  • 33
0 votes
2 answers
639 views

Calculate homography by two parrallel lines

I know two lines (in the form Ai x'+Bi y'+ Ci =0) on the image, which is a pair of parallel line (in the form x = ki) on a real word plane(just like a pair of road traffic marking line). How ...
Mad S.Zhong's user avatar
0 votes
0 answers
413 views

How to find the coordinates of the fourth vertex of a square in a projective perspective

If I suppose that I know the coordinate of three points (eg. A'B'C') in a 2D coordinate system of A'B'C'D', my question is how can I find the coordinate of the fourth point D' (the same question for A'...
Ja_cpp's user avatar
  • 2,304

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