Sheer compensation and uneven grid size in camera calibration

malharjajoo
56 ●1 ●2 ●8

Hi,

I have done camera calibration recently and the output only seems to contain the focal length (f) and principal point (cx and cy) as indicated here.

However, from the theory it is known that (digital) camera sensors can involve sheer and unequal sizes pixel grids in x and y direction.

$C:\fakepath\sheer.png$

My Question: Does openCV account for sheer or unequal grid sizes ? I can't find this in the docs ....

Thanks!

Comments

unequal grid sizes : fx != fy (CALIB_FIX_ASPECT_RATIO)

About skew factior I think it is always 0 in opencv

LBerger ( 2018-01-15 02:08:50 -0600 )edit

Thanks! I remember now. Also, is there any reason the skew factor is always = 0 ?

malharjajoo ( 2018-01-15 07:43:11 -0600 )edit

see Multiple View Geometry in computer vision p 157 : x- and y- axes are not perpendicular

LBerger ( 2018-01-15 08:02:56 -0600 )edit

The book's not free, is it ?

malharjajoo ( 2018-01-15 15:41:02 -0600 )edit

No it is not

LBerger ( 2018-01-16 03:17:14 -0600 )edit

Thanks! If you can convert your comment as an answer, I will mark it as the solution as well.

malharjajoo ( 2018-01-20 10:16:30 -0600 )edit