Attention: Answers.ros.org is deprecated as of August the 11th, 2023. Please visit robotics.stackexchange.com to ask a new question. This site will remain online in read-only mode during the transition and into the foreseeable future. Selected questions and answers have been migrated, and redirects have been put in place to direct users to the corresponding questions on Robotics Stack Exchange. Additional details are available here.

Focal Length from Monocular Calibration

asked 2012-01-01 11:16:23 -0500

jamesp
13 ●1 ●2 ●4

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

edit retag flag offensive close merge delete

add a comment

1 Answer

Sort by » oldest newest most voted

answered 2012-01-01 13:04:32 -0500

Dan Lazewatsky
9115 ●79 ●103 ●160 http://dan.lazewatsky.com/

updated 2012-01-01 13:05:16 -0500

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.

edit flag offensive delete link

Comments

Thank you for your reply!

jamesp ( 2012-01-08 21:13:41 -0500 )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 -0500 )edit

add a comment

Question Tools

Stats

Asked: 2012-01-01 11:16:23 -0500

Seen: 1,469 times

Last updated: Jan 01 '12

Focal Length from Monocular Calibration edit

1 Answer

Comments

Question Tools

Stats

Related questions

Focal Length from Monocular Calibration