## Die Suche ergab 7 Treffer

16. Jun 2011 14:34
Forum: Computer Vision
Thema: Assignment 3 - Problem 3 - Thresholding ?
Antworten: 1
Zugriffe: 1361

### Assignment 3 - Problem 3 - Thresholding ?

In figure 2 of problem 3 (feature matching) you can see several points which are not connected to another point. As far as I can tell, there HAS to be a threshold applied onto the distances between the points, otherwise in at least one image, every point should have a connected point. Do we also hav...
1. Jul 2010 13:08
Forum: Computer Vision
Thema: Scale of extracted parameters (projecting matrix)
Antworten: 11
Zugriffe: 4105

### Re: Scale of extracted parameters (projecting matrix)

@JanEisklar

Sorry, I think you misunderstand me. It looks like you tried to normalize the reconstructed projection matrix P (from make_camera.m), but I've meaned that you have to normalize the computed projection matrix P before applying RQ-decomposition.

Sincerly,
30. Jun 2010 16:46
Forum: Computer Vision
Thema: Scale of extracted parameters (projecting matrix)
Antworten: 11
Zugriffe: 4105

### Re: Scale of extracted parameters (projecting matrix)

@Christoph Thanks for clearing - it works. @runaway We got the same results as you did if we remove our normalization. You have to normalize your projection matrix P to the euclidean norm of the last row of M (see http://de.wikipedia.org/wiki/Projektionsmatrix#Geometrische_Deutung_der_Projektionsmat...
29. Jun 2010 17:46
Forum: Computer Vision
Thema: Scale of extracted parameters (projecting matrix)
Antworten: 11
Zugriffe: 4105

### Re: Scale of extracted parameters (projecting matrix)

Hi, we calculated the calibration matrix K but captured weird results. In our case the coefficent alpha_y = -alpha_x. If we account that in backprojection we got the correct result. How could it that alpha_x = -alpha_y? Is that some problem with the RQ-decomposition as the RQ-Decomposition is not un...
25. Jun 2010 10:35
Forum: Computer Vision
Thema: Exercise 4, Q1b
Antworten: 1
Zugriffe: 855

### Exercise 4, Q1b

Hi, we think there is an error in the starting kit of exercise 4 in question 4b. In line 22 there is a conversion from homogeneous to cartesian and back, cart2hom(hom2cart(squares)); Since the coordinates of "squares" are in cartesian, this call is in the wrong way round we think. Hope this hint cou...
21. Mai 2010 16:46
Forum: Computer Vision
Thema: Ex3 1b
Antworten: 1
Zugriffe: 340

### Ex3 1b

Hi @all,

we are not sure how the output Hessian matrix (H in hessian.m) should look like.

Do we have to concatenate the single derivatives [Ixx Ixy; Ixy Iyy] or do we have to provide the determinant det(H) like the cornerness map from the harris detector?

Thanks
17. Mai 2010 18:47
Forum: Computer Vision
Thema: Ex 2 1b)
Antworten: 1
Zugriffe: 290

### Ex 2 1b)

Hi @all, we have a question on the exercise mentioned above. In this thread it was said by Diane, that all histograms should be normalized. So, we wonder which normalization method should be used. We first think that we should normalize using the MAX-norm, but then look at the m-file for the Dx/Dy-h...