How to transform pixel coordinate to camera coordinate

Robotics & Edge Computing Robotics - Isaac Isaac Gym
1

Hello, I am now trying to get the 3D position from a camera image. But I did not find the camera intrinsic parameters to get the relationship between pixels and meters.

2

Hi @291797245

There is the next subsection about Camera Intrinsics in the Isaac Gym docs

Screenshot from 2022-04-30 11-55-10
Screenshot from 2022-04-30 11-55-101113×821 147 KB

3

Thanks a lot. Actually, I have found this page, but I do not really know the meaning of projection matrix and the view matrix. Is the projection matrix to transform camera coordinate to image coordinate? But how to transform the image coordinate to pixel coordinate? And what is the meaning of view matrix?
Plus, I do not think the projection matrix is to transform camera coordinate to image coordinate after some trials.
Thanks again!

4

Hi @291797245

In the following links, there is information about the matrices, for example

Also, you can check the following snippet (shared by @gavrielstate) that uses the projection and view matrix to generate the point cloud

5

Thanks a lot!!!
I think this website is really helpful!
Plus, I found that the transformation from pixel coordinate to image coordinate can be calculated by using depth image.
Thanks!

6

May i ask that Is this simple and correct: the camera coordinates are pointwise multiplied by the inverse matrix of the view matrix to get the coordinates in the world coordinate system。