Projective geometry is an incidence geometry of colinearity preserving transformations. Its use is widespread in computer graphics, computer vision, image registration, photography, among others. Homogeneous coordinates are commonly used to represent objects (point, lines, planes etc.) in real projective geometry. These are well-known to represent translation, rotation and perspective transformation simply as matrix-vector multiplication.
Questions tagged [projective-geometry]
94 questions
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Calculate distance between two points in a perpective image
I want to verify the distance between two points C and D (CD) in a perpective image.
The picture is taken in my living room. Dimension of each tiles is 0.6x0.6 (in meters).
Real world measurements:
Distance between point A and point D (AD) = 1.8…
Sarweshkumar C R
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How to estimate camera pose according to a projective transformation matrix of two consecutive frames?
I'm working on the kitti visual odometry dataset. I use projective transformation to register two 2D consecutive frames(see projective transformation example here
). I want to know how this 3*3 projective transformation matrix is related to the…
leo
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Projective Geometry - Find Plane in 3D using eigen
I'm trying to construct a plane out of three points in 3D.
I want to use projective geometry to achieve this.
As far as I know, one can "simply" solve the following to find a plane:
A * x = 0 ,where
A is a 3x4 Matrix - each row being one of the…
NewTech
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Reconstruct 3D points from two images, given camera movement
I am trying to reconstruct the real-world coordinates of 3D points from two images taken from the same camera. The camera is not calibrated, but the movement (translation and rotation) is known. In short:
Requirement:
No calibration
Extra…
Nick Lee
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how to produce projective transformation matrix best fit for multiple 4-point sets?
Normally I am using this kind of matlab code to do a projective transformation with a single set of reference points:
fixedpoints = [0 0; 50 0; 50 100; 0 100];
movingpoints= [752 361; 888 361; 885 609; 736…
peter e
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Conjugate rotation transformation in OpenCV
I am trying to apply a certain rotation to an image, but it doesn't work as expected. The rotation I have is:
[0.109285 0.527975 0.000000
-0.527975 0.109285 0.000000
0.000000 0.000000 1.000000]
Which should be a rotation of…
aledalgrande
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Convert pitch, roll, and yaw angles
I have a pitch, roll, and yaw angles (in degrees). I want to find the angle to north.
My goal is to transform this info (pitch+roll+yaw) to a simple compass degrees.
1smae1
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Recovering pose from essential matrix gives inconsistent sign of translation vector
I have three views with point correspondences and I want to compute the pose of the camera at the second and the third view. I therefore generate a random dataset (no noise) containing points in the different views with known rotation and…
takahashi
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Epipolar constraint in the 8-point algorithm
I am developing a system using two cameras, and I want to know is it possible that the epipolar constraint can be satisfied by a matrix that this not part of the set of essential matrices? If so, in which situation do I have to handle this matrix?
GovernorBandicoot
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Wrong Homography Transformation
Recently, I studied homography transformation (which adds an addition dimension to 2D points[x,y]->[wx,wy,x]) and projective geometry.
When I tried to transform the bottom part of photo 1 to the top of a new image, the result is wrong.
The reason I…
Alex Lin
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Creating a Cube-based 3-Dimensional Game
I am trying to create a 3-dimensional game that is based entirely off of cubes of the exact same size. I wanted to learn how to make my own 3-dimensional game using only 2-dimensional game libraries. Currently, the way I am doing is that I have an…
Sidd Singal
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Rectification-projective2d
Does any one know how this function (projective2d) works? I have a code for rectification and my Matlab have error with this function (Undefined function 'projective2d' for input arguments of type 'double'), however I think it should work for double…
user3174909
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How to "translate" the movement of the camera to the image?
I'm doing some work with a camera and video stabilization with OpenCV.
Let's suppose I know exactly (in meters) how much my camera has moved from one frame to another and I want to use this to return the second frame where it should be.
I'm sure I…
user2987702
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Algorithm to interpolate any view from individual view mapped on a sphere
I'm trying to create a graphics engine to show point cloud data (in first person for now). My idea is to precalculate individual views from different points in the space we are viewing and mapping them into a sphere. Is it possible to interpolate…
user11615
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MATLAB: projective transformations
I have a picture
and I want to get projective transformation by shifting it back like this:
but the only result I can see is this:
and I cannot find my mistake. My code (A - picture I want to transform):
p=0.25;
a=p*rows(A);
U = @(m, n) ([1 1; 1…
myname
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