OpenCV Q&A Forum - RSS feedhttp://answers.opencv.org/questions/OpenCV answersenCopyright <a href="http://www.opencv.org">OpenCV foundation</a>, 2012-2018.Wed, 04 Sep 2013 18:02:22 -0500How is the [R|t] matrix actually found when using the EPnP algorithm?http://answers.opencv.org/question/17722/how-is-the-rt-matrix-actually-found-when-using-the-epnp-algorithm/I am using OpenCV's **EPnP algorithm** to solve for the pose of an aircraft with a known pattern of LEDs. I have been able to get pose estimation working without too much trouble, but I am now in the writing phase of my thesis and have some questions about how the algorithm actually works. I was hoping that someone could point me towards some information that might help to put me on the right track.
I have found this paper (http://cvlabwww.epfl.ch/~lepetit/papers/lepetit_ijcv08.pdf) to be very helpful in understanding how the four control points are found in the camera frame of reference, but the paper does *not* go on to explain ***how the rotation-translation matrix [R|t] is actually found***, which gives us the pose information.
I have looked through the OpenCV source code and have located the "compute_R_and_T()" function, but have struggled to understand what all is going on. Are there any technical papers or OpenCV documentation that could help me out?
Thanks,
MikeMon, 29 Jul 2013 13:18:15 -0500http://answers.opencv.org/question/17722/how-is-the-rt-matrix-actually-found-when-using-the-epnp-algorithm/Comment by FndrPlayer39 for <p>I am using OpenCV's <strong>EPnP algorithm</strong> to solve for the pose of an aircraft with a known pattern of LEDs. I have been able to get pose estimation working without too much trouble, but I am now in the writing phase of my thesis and have some questions about how the algorithm actually works. I was hoping that someone could point me towards some information that might help to put me on the right track.</p>
<p>I have found this paper (<a href="http://cvlabwww.epfl.ch/~lepetit/papers/lepetit_ijcv08.pdf">http://cvlabwww.epfl.ch/~lepetit/papers/lepetit_ijcv08.pdf</a>) to be very helpful in understanding how the four control points are found in the camera frame of reference, but the paper does <em>not</em> go on to explain <strong><em>how the rotation-translation matrix [R|t] is actually found</em></strong>, which gives us the pose information.</p>
<p>I have looked through the OpenCV source code and have located the "compute_R_and_T()" function, but have struggled to understand what all is going on. Are there any technical papers or OpenCV documentation that could help me out?</p>
<p>Thanks,</p>
<p>Mike</p>
http://answers.opencv.org/question/17722/how-is-the-rt-matrix-actually-found-when-using-the-epnp-algorithm/?comment=20188#post-id-20188Does anybody know how I can get a hold of Alexander Shishkov? It looks like he wrote the EPnP algorithm code and is the most equipped to answer my question. Thank you!Wed, 04 Sep 2013 18:02:22 -0500http://answers.opencv.org/question/17722/how-is-the-rt-matrix-actually-found-when-using-the-epnp-algorithm/?comment=20188#post-id-20188