1 | function [F, inls] = rEG(u, th, th7, conf) |
---|
2 | |
---|
3 | %rEG Robust computation of epipolar geometry based on RANSAC |
---|
4 | % |
---|
5 | % [F, inls] = rEG(u, th, th7, conf) |
---|
6 | % u point correspondences (6xn), where n is the number of corrs. |
---|
7 | % th threshold value for the Sampson's distance (see FDs) |
---|
8 | % th7 threshold for inliers to iterate on F (default = th) |
---|
9 | % conf confidence level of self-termination (default = .95) |
---|
10 | |
---|
11 | MAX_SAM = 100000; |
---|
12 | iter_amount = .5; |
---|
13 | |
---|
14 | if nargin < 3 |
---|
15 | th7 = th; |
---|
16 | end; |
---|
17 | |
---|
18 | if nargin < 4 |
---|
19 | conf = .95; |
---|
20 | end; |
---|
21 | |
---|
22 | len = size(u,2); |
---|
23 | ptr = 1:len; |
---|
24 | max_i = 8; |
---|
25 | max_sam = MAX_SAM; |
---|
26 | |
---|
27 | no_sam = 0; |
---|
28 | no_mod = 0; |
---|
29 | |
---|
30 | while no_sam < max_sam |
---|
31 | for pos = 1:7 |
---|
32 | idx = pos + ceil(rand * (len-pos)); |
---|
33 | ptr([pos, idx]) = ptr([idx, pos]); |
---|
34 | end; |
---|
35 | |
---|
36 | no_sam = no_sam +1; |
---|
37 | |
---|
38 | aFs = fu2F7(u(:,ptr(1:7))); |
---|
39 | |
---|
40 | for i = 1:size(aFs,3) |
---|
41 | no_mod = no_mod +1; |
---|
42 | aF = aFs(:,:,i); |
---|
43 | Ds = mfFDs(aF,u); |
---|
44 | % Ds = fFDs(aF,u); |
---|
45 | v = Ds < th; |
---|
46 | v7 = Ds < th7; |
---|
47 | no_i = sum(v); |
---|
48 | |
---|
49 | if max_i < no_i |
---|
50 | inls = v; |
---|
51 | F = aF; |
---|
52 | max_i = no_i; |
---|
53 | max_sam = min([max_sam,nsamples(max_i, len, 7, conf)]); |
---|
54 | end |
---|
55 | |
---|
56 | if sum(v7) >= 8 + iter_amount*(max_i - 8) |
---|
57 | aF = u2F(u(:,v7)); |
---|
58 | Ds = mfFDs(aF,u); |
---|
59 | % Ds = fFDs(aF,u); |
---|
60 | v = Ds < th; |
---|
61 | no_i = sum(v); |
---|
62 | if max_i < no_i |
---|
63 | inls = v; |
---|
64 | F = aF; |
---|
65 | max_i = no_i; |
---|
66 | exp_sam = nsamples(max_i, len, 7, .95); |
---|
67 | max_sam = min([max_sam,exp_sam]); |
---|
68 | end |
---|
69 | end |
---|
70 | end |
---|
71 | end |
---|
72 | |
---|
73 | if no_sam == MAX_SAM |
---|
74 | warning(sprintf('RANSAC - termination forced after %d samples expected number of samples is %d', no_sam, exp_sam)); |
---|
75 | end; |
---|
76 | |
---|
77 | |
---|
78 | |
---|
79 | |
---|
80 | |
---|
81 | |
---|
82 | |
---|
83 | |
---|
84 | |
---|
85 | |
---|