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### Understanding the Result of Camera Calibration and its Units

Hi,

I am quite new to camera calibration.

I have 35 images, based on the following functions :

findChessboardCorners() cornerSubPix() drawChessboardCorners() calibrateCamera()

I now have

1. Camera Matrix - 3x3 dimension
2. Distortion Coefficient - 1x5 dimension
3. Rotation Vector - 35x3 dimension
4. Translation Vector - 35x3 dimension

Questions :

1. camera matrix

 [ 2421.70421334667, 0, 2138.107444179007;
0, 2429.244140012221, 1136.772764836856;
0, 0, 1]


In the above , what are the units of fx, fy , Cx and Cy ?

1. Distortion Coefficient
[-0.2877455633196141,
0.2968104208806526, -0.001127291269463514, -0.002010576239298727, -0.3457992571078199]


Do we have any Units for K1, K2, P1, P2, K3 ?

1. Rotation Vector
[-0.1019788539700399; 0.3918509002001774; 0.0734955967493143]
[-0.1165422449849887; 0.5017699087572564; 0.4257284491781231]
[-0.1233545118567792; 0.5922964766688477; 1.001270611741778]
[-0.5253276710841507; -0.01653828323651414; -1.386034124708322]
so on ... for all 35 images


What about the unit of Rotation Matrix? How should I understand it? What does this values mean?

1. Translation Vector
[152.8348988935562, -168.8318694822206; 951.100836109663]
[191.0103136141713; -207.2053481732149; 963.7313891311128]
[307.0885175766131; -212.1491832662802; 945.4874998124949]
[221.391205120318; -22.64308775049023; 910.7108013142725]
so on ... for all 35 images


What about the unit of Translation Vector? How should I understand it ? What does its values mean?

I also tries the camera calibration app in Matlab, I set the same image but it does not show the same result?