A4 - Problem 3 - eightpoint algorithm

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robert.n
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A4 - Problem 3 - eightpoint algorithm

Beitrag von robert.n » 16. Jul 2011 19:41

I have a problem implementing the eightpoint algorithm.

My \(V_A^T\) has only 8 entries. :?: However, on slide 36 nine entries are referenced when the matrix \(\tilde{F}\) ("F tilde") is built (l10-twoview-v1.pdf).

tanne
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Re: A4 - Problem 3 - eightpoint algorithm

Beitrag von tanne » 17. Jul 2011 00:00

sounds like your created equationsystem is wrong, e.g. the matrix you use with svd.

robert.n
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Re: A4 - Problem 3 - eightpoint algorithm

Beitrag von robert.n » 17. Jul 2011 01:03

I didn't stack the equations (each vector corresponds to one row), instead I used the vectors as columns of my matrix. Apparently I got confused by the wikipedia article. (They use the vectors as columns.)

Fundamental matrix still does not seem to be correct, though.


//EDIT:
I got confused by Matlab's transpose operator, while reading the slides. -.- I noticed that earlier, actually, and fixed my code almost completely. But only a few minutes ago I noticed that I missed something: T and T' are two entirely different matrices, too! Arggghhh... me :arrow: dumbass... gah :cry:

tanne
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Re: A4 - Problem 3 - eightpoint algorithm

Beitrag von tanne » 17. Jul 2011 12:37

robert.n hat geschrieben: //EDIT:
I got confused by Matlab's transpose operator, while reading the slides. -.- I noticed that earlier, actually, and fixed my code almost completely. But only a few minutes ago I noticed that I missed something: T and T' are two entirely different matrices, too! Arggghhh... me :arrow: dumbass... gah :cry:
yeah right, i was confused by the notation too. you have one T matrix for each set of points.

qgao
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Re: A4 - Problem 3 - eightpoint algorithm

Beitrag von qgao » 20. Jul 2011 12:56

robert.n hat geschrieben:My \(V_A^T\) has only 8 entries.
\(V_A^T\) should have 9 entries, because there is one additional constraint |f| = 1.

qgao
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Re: A4 - Problem 3 - eightpoint algorithm

Beitrag von qgao » 20. Jul 2011 12:58

robert.n hat geschrieben:T and T' are two entirely different matrices, too! Arggghhh... me :arrow: dumbass... gah :cry:
Right! T' is not the transpose of T, but a different matrix.

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