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I am trying to implement an algorithm for calculation of 3D coordinates from corresponding image coordinates pair and I doesn't work fine. I am receiving different results when starting with expresions for x and y. This is what I am doing: 1. Stereo calibrate my setup 2. Inverse camera matrix for both cameras 3. Calculate the normalized coordinates of corresponding points for both cameras - by multipication of inversed camera matrix and homogenous pixel point coordinates 4. Calcule x3 physical/real world coordinate of the point using Rotation and Translation matrices (given by stereo calibration procedure). 5. Calculating x1 and x2 coordinates as it is written in the article
Are you sure there are no mistakes in subsection about 3D poin coordinates? — Preceding unsigned comment added by 194.29.140.25 ( talk) 11:48, 7 June 2011 (UTC)
I think (but I am not positive), that the formula for translation-from-essential is [t] = UZU' instead of VZV'. Could someone smarter check? 2001:718:1E03:5166:F2DE:F1FF:FE7E:60BC ( talk) 19:22, 6 November 2013 (UTC)
I entirely agree, http://cseweb.ucsd.edu/classes/sp03/cse252/MaSKS_Ch5.pdf this document on page 4 shows the formula for [t]x = URZU'. Moreover, I have been implementing it with openCV and the results add up with this correction and doesn't with V. — Preceding unsigned comment added by 176.186.116.116 ( talk) 18:37, 11 February 2014 (UTC)
"if \mathbf{y} and \mathbf{y}' are homogeneous normalized image coordinates"
There's no requirement that the points be normalized. This is trivial true as if \mathbf{y} is not normalized, then it is a linear multiple of some corresponding normalized point. i.e. a * \mathbf{y}. So the equation y' * E * y = 0 becomes a * a * y' * E * y = 0 which allows both sides to be divided a * a. — Preceding unsigned comment added by 124.168.160.34 ( talk) 20:04, 30 July 2014 (UTC)
I have come across sources that show instead of (note transpose in first version). E.g. here http://www.ecse.rpi.edu/~qji/CV/cvfinalproject.pdf (page 2) and here http://cseweb.ucsd.edu/classes/wi05/cse252a/lec14.pdf (page 3, second slide). Also in my experience the former version works in practice while the later does not. — Preceding unsigned comment added by Scuac ( talk • contribs) 20:42, 4 September 2014 (UTC)
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I am trying to implement an algorithm for calculation of 3D coordinates from corresponding image coordinates pair and I doesn't work fine. I am receiving different results when starting with expresions for x and y. This is what I am doing: 1. Stereo calibrate my setup 2. Inverse camera matrix for both cameras 3. Calculate the normalized coordinates of corresponding points for both cameras - by multipication of inversed camera matrix and homogenous pixel point coordinates 4. Calcule x3 physical/real world coordinate of the point using Rotation and Translation matrices (given by stereo calibration procedure). 5. Calculating x1 and x2 coordinates as it is written in the article
Are you sure there are no mistakes in subsection about 3D poin coordinates? — Preceding unsigned comment added by 194.29.140.25 ( talk) 11:48, 7 June 2011 (UTC)
I think (but I am not positive), that the formula for translation-from-essential is [t] = UZU' instead of VZV'. Could someone smarter check? 2001:718:1E03:5166:F2DE:F1FF:FE7E:60BC ( talk) 19:22, 6 November 2013 (UTC)
I entirely agree, http://cseweb.ucsd.edu/classes/sp03/cse252/MaSKS_Ch5.pdf this document on page 4 shows the formula for [t]x = URZU'. Moreover, I have been implementing it with openCV and the results add up with this correction and doesn't with V. — Preceding unsigned comment added by 176.186.116.116 ( talk) 18:37, 11 February 2014 (UTC)
"if \mathbf{y} and \mathbf{y}' are homogeneous normalized image coordinates"
There's no requirement that the points be normalized. This is trivial true as if \mathbf{y} is not normalized, then it is a linear multiple of some corresponding normalized point. i.e. a * \mathbf{y}. So the equation y' * E * y = 0 becomes a * a * y' * E * y = 0 which allows both sides to be divided a * a. — Preceding unsigned comment added by 124.168.160.34 ( talk) 20:04, 30 July 2014 (UTC)
I have come across sources that show instead of (note transpose in first version). E.g. here http://www.ecse.rpi.edu/~qji/CV/cvfinalproject.pdf (page 2) and here http://cseweb.ucsd.edu/classes/wi05/cse252a/lec14.pdf (page 3, second slide). Also in my experience the former version works in practice while the later does not. — Preceding unsigned comment added by Scuac ( talk • contribs) 20:42, 4 September 2014 (UTC)