Hi everybody, Short question: How do you compute the pose of the camera in real world coordinates (x,y,z and rotation) given a 4x4 model view matrix of a particular object and the known location and rotation of that object in the real world? Question explained in more detail: I have a question related to a somewhat special 3D/real world problem: I am using an augmented reality (AR) library that detects specific markers (2D patterns) in pictures taken of the real world (imagine a picture of an office with a poster hanging on one of the walls, where that poster shows a very distinct 2D marker pattern). The idea behind AR is that you display such real world pictures on a screen and overlay rendered 3D objects; for example you could render a shelf next to the wall where the marker was detected. For this purpose the AR library I am using returns an OpenGL style model view matrix for each marker it detected. If AR in OpenGL is all you want to do then that is all you need to correctly render objects onto markers. However, I am not trying to do AR but rather estimate the camera's real world pose. To me it seems that by having knowledge of the true, real world location of a marker and the model view matrix returned by the AR library for that particular marker, it should be possible to determine the real world pose of the camera (where we assume a pinhole camera for simplicity). I am interested in getting the (x,y,z) coordinates and the rotation of the camera in the real world. How would you compute that? Thanks a lot! -Jonas

I agree. I forgot to mention that I also know the size of the object.

Isn't this a cross-post?

@The OP: It looks like there are more responses in your other thread, so I'd recommend continuing the discussion there.