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Units of the camera intrinsic parameters

I read the webpage (https://developer.microsoft.com/en-us/windows/holographic/locatable_camera) that talks about the intrinsic parameters being part of the projection transform.

Matrix4x4 format Terms
m11 m12 m13 m14 fx 0 0 0
m21 m22 m23 m24 skew fy 0 0
m31 m32 m33 m34 cx cy A -1
m41 m42 m43 m44 0 0 B 0

I implemented some code to take a picture with the Hololens RGB camera in pixel format BGRA32. After taking the picture, I get the PhotoCapture.PhotoCaptureResult and the PhotoCaptureFrame in the callback method. I used the PhotoCaptureFrame TryGetProjectionMatrix method to retrieve the projection transformation. The transformation I got is the following:

1.51969 0.00000 -0.00170 0.00000
0.00000 2.69773 -0.02484 0.00000
0.00000 0.00000 -1.00000 0.00000
0.00000 0.00000 -1.00000 0.00000

It seems the transformation is already in the form

Fx 0.0 Cx
0.0 Fy Cy
0.0 0.0 1.0

I then did a video capture of the checkerboard with the Hololens RGB camera. I ran the opencv camera calibration example, and got the following intrinsic values:

1.7230957099738822e+04 0.0 7.0350000000000000e+02
0.0 1.7230957099738822e+04 3.9550000000000000e+02
0.0 0.0 1.0

I know that these values are in pixels. Looking at the values from the projection transformation, they don't match or are even close to each other.

I'd like to ask if the projection matrix that I got from the picture is the correct matrix that has the intrinsic parameters. If so, what units are the intrinsic parameters from the projection matrix in?

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