Linked Questions

34
votes
7answers
22k views

How to find image coordinates of the rendered vertex?

I have a simple mesh of a cube. I would like to know what are the coordinates of each vertex in the rendered image (i.e. for each 3d vertex I'd like to know it's pixel coordinates). Is there a way ...
15
votes
3answers
14k views

How can I get the camera's projection matrix?

As asked. I need a way to get the projection matrix of the active camera, via python. EDIT: I think this question is different from the one asked here, because getting a matrix is different from ...
9
votes
1answer
7k views

What is blender's camera projection matrix model?

I have question what is blender's camera projection model. I want to use blender to my computer vision experiment which need to compare real photo and CG. For real photo, I used camera matrix K for ...
5
votes
1answer
3k views

Distortion Coefficients and Camera intrinsic of blender's cameras?

I'm looking to run a SLAM algorithm over images generated from blender but I need to know the intrinsic properties of the camera. I've taken a brief look at the python api and there doesn't seem to be ...
2
votes
1answer
2k views

blender camera from 3x4 matrix

In computer vision, the transformation from 3D world coordinates to pixel coordinates is often represented by a 3x4 (3 rows by 4 cols) matrix P as detailed below. Given P I need code to return a ...
4
votes
1answer
1k views

How can I get the projection matrix of a panoramic camera with a fisheye equisolid lens?

I am working on a project in which i used the panoramic camera with fisheye equisolid lens on Cycles render. For some tests, I need the projection model that uses by this camera to project a 3D point ...
0
votes
0answers
1k views

How to project a point from 3D to 2D in blender?

I know how to obtain the 4x4 projection matrix of the camera in Blender, but it seems its format is different from the standard camera projection matrices. I would appreciate it if someone explains ...
1
vote
1answer
663 views

what is the meaning of 4x4 projection matrix?

I want to know the meaning of 4x4 projection matrix and how can I transform it 3x4 usual shape. I understand that, in Blender, I can compute projection matrix as following, ...
1
vote
0answers
566 views

How to compute image coordinates from projection matrix?

I get the projection matrix from the Camera object (projection_matrix) and it is a 4x4 matrix. I have an object in the scene whose "worldPosition" is known (x,y,z). Now I want to project the 3D point (...
3
votes
0answers
303 views

stereo camera extrinsic parameter

In Blender, we have an option to make Blender camera to be a stereo system. I found this post very helpful in getting the camera parameters (including intrinsic and extrinsic parameters). Yet, the ...
2
votes
2answers
143 views

How to set object at a specific depth from the camera, at a certain pixel

I want to set an object at a certain distance (or depth) relative to the camera; and also at a particular pixel. Example: I set up a camera at a random position in blender. I want an 1280x720 image. ...
1
vote
0answers
144 views

Homography between two planes with rotation and translation

I generated two camera views using Blender with rotation and translation. Now I want to know how to compute homography between camera view A to B? I found how to compute homography for rotation only ...
2
votes
1answer
48 views

What Lens Model does Blender use for Camera Tracking?

I recently started working with the camera-tracking estimator to produce short augmented reality videos. I'd like to learn more about the lens model and its parameters (K1, K2, etc...). Can anyone ...
0
votes
1answer
15 views

How to calculate the transformation from the pivot point to each stereo camera

I checked the API documentation and this related question, and it looks like there is no easy way to get the pose of both the left-stereo and right-stereo cameras. So, I think the only solution is to ...