Hello,
 
I would like to calibrate shots with image modeler and then use the calibration in a program so I need the transformation matrix which serve in image Modeler.
I looked at the .rzi file but I just found the positions of all points in 2D and 3D but no transformation matrix. that is to say that you re-evaluate the matrix every time that you load a project ?
Is it possible to access to this matrix when the project is opened or to calculate it simply ?
 
thank you,
Laure

Hello Laure,
 
 The calibrated camera informations are between <CFRM> tags :
 
<SHOT i="3" n="P9170067.JPG" ci="1" w="1600" h="1200">
  <CFRM cf="1" fovx="56.9484" rd="0.167074">
   <T x="-13.4346" y="-4.40166" z="3.34393"/>
   <R x="91.076" y="-1.12015" z="-66.0866"/>
  </CFRM>
 
......
</SHOT>
 
T: is the translation (position) of the camera
R: is the rotation (Euler angles)
fovx: field of view horizontal (in degree)
rd: the radial distortion
 
Best,
 
Stef

Hello Steph,
 
When you talk about euler angles, you mean real euler angles (with 3 rotations Z,Y,Z where repere changes each times), or just a rotation X, followed by a rotation Y, followed by a rotation Z ?
 
Thx.

Hello,
 
  Its not the ZYZ case, but your second asumption X,Y,Z in that order.
 
Best,
 
Stef

Thx and sorry for your name SteF
 
 

Hello, Stef!
 
I used MATLAB Camera Calibration Toolbox
(http://www.vision.caltech.edu/bouguetj/calib_doc/)
for calibration before that. And I would like to translate the calibration
data
computed with IM to the format used in MATLAB Camera Calibration Toolbox
(http://www.vision.caltech.edu/bouguetj/calib_doc/htmls/parameters.html).
Can you please give me the exact and detailed specification on the camera
calibration data stored in the rzi file.
 
Here is the example of the calibration data computed with IM:
<CINF i="1" n="Camera Device" sw="2048" sh="1536" fbs="c" fovx="45.6673"
ds="c"/>
<SHOT i="1" n="001.jpg" ci="1" w="2048" h="1536">
<CFRM cf="1" fovx="49.4626" rd="0.250264">
<T x="299.278" y="28.9404" z="139.605"/>
<R x="44.8392" y="38.9884" z="60.3329"/>
</CFRM>
 
And I need to get the extrinsic parameters from this data. As I understood
<T ... > defines absolute camera position in the world coordinate system. Am
I right? Does <R ... > define the rotation of the camera around the camera center?
How can I get the rotation matrix (or extrinsic camera calibration matrix, or
camera projection matrix) from the rotation vector, stored in <R ... >?
It was said, that R defines the Euler angles, but I didn't completely
understand the convention used (what do x, y, z in <R ... > mean?). Different conventions are
described in http://mathworld.wolfram.com/EulerAngles.html, for example. Which
formulas for calculation of rotation matrix A (according to that article
terms) should I use? I guess I tried all of them, but still did not succeeded.
Please help!
 
Thanks in advance!