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Focal Length from Monocular Calibration

asked 2012-01-01 11:16:23 -0600

jamesp
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I was wondering if the parameters saved from running the cameracalibrator.py node contain the focal length/s of the camera somewhere inside. If not, is it possible to determine a focal length based on these values?

Thanks

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answered 2012-01-01 13:04:32 -0600

Dan Lazewatsky
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updated 2012-01-01 13:05:16 -0600

The camera matrix, as written out by cameracalibrator.py is as follows:

Fx  0  Cx
0   Fy Cy
0   0   1

where Fx and Fy are the x and y focal lengths in pixels, and (Cx, Cy) is the principal point.

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Thank you for your reply!

jamesp ( 2012-01-08 21:13:41 -0600 )edit

hi, but these Fx and Fy can be found from camera parameters (intrinsic), but what is the actual focal length of the camera ? in formula Fx = f * Mx , where Mx is pixel/mm on image sensor. how can we get that !! any idea !

zubair ( 2018-12-27 04:56:22 -0600 )edit

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Asked: 2012-01-01 11:16:23 -0600

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Last updated: Jan 01 '12

Focal Length from Monocular Calibration edit

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Focal Length from Monocular Calibration