Coordinate frame transformation from NED to OpenCV convention, and the Pinhole Camera Model

asked 2020-08-02 12:28:00 -0600

leafdet gravatar image

updated 2020-08-02 12:30:14 -0600

Hello, I'm working on an SFM module where I have camera coordinates wrt a world coordinate system (in NED). I have the calibrated camera intrinsics matrix, and with the R,T of the camera wrt world, I compute the Projection matrix (intrinscs matrix * R|T) for each image, and camera position. However, I'm not sure if this Projection matrix is right since the R|T is in NED, and openCV uses a different convention.I'm trying to use the CV::SFM::triangulatePoints, but I'm not getting consistent results. How will this affect the projection matrix, and is the conversion of the poses to the OpenCV frame necessary?

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mind telling us, what NED is ? ;)

with the R,T of the camera wrt world,

no such thing as a "world" here. do you mean the R,t Mat's from calibration ? they're camera <--> chessboard, and somehow useless for further svm calculations

berak gravatar imageberak ( 2020-08-02 12:50:54 -0600 )edit

@berak NED is the North East Down convention. It's a very commonly used convention in drones, or aerospace :). In the Pinhole Camera Model, the camera's position has a R|T wrt some origin in the world (

leafdet gravatar imageleafdet ( 2020-08-03 02:07:24 -0600 )edit