Structure and Motion Toolkit in MATLAB

Philip Torr (view profile)

04 Mar 2004 (Updated )

Structure and Motion Toolkit in MATLAB.

torr_display_epipolar(f,ax_handle2,ax_handle3,m3)
```%	By Philip Torr 2002
% so we display an epipolar line from image 1 into image 2
%%%%%%%

function torr_display_epipolar(f,ax_handle2,ax_handle3,m3)

% (x2 y2 m3) F (x1 y1 m3)'
%  (image 2) F ( image 1)'

%while 1

%this takes one image and draws the corresponding epipolar line.
Fmat = [[f(1) f(2) f(3)]; [f(4) f(5) f(6)];[f(7) f(8) f(9)]];

[U,S,V] = svd(Fmat);
S(3,3) = 0;
F2 = U*S*V';

[v,d] = eig(F2);
ee = v(:,1);
%Fmat * ee

axes(ax_handle2);
hold on
[Xcur,Ycur] = GINPUT;
n_plots = length(Xcur);

plot(Xcur,Ycur, 'w+','LineWidth',2);
%  plot(matches12(i,1), matches12(i,2), 'b+','LineWidth',2);
xxx1 = [Xcur,Ycur, ones(n_plots,1) * m3];

% (x2 y2 m3) F (x1 y1 m3)'
%  (image 2) F ( image 1)'

el2 = F2 * xxx1';
%is this the wrogn way round>
el2 = el2';

axes(ax_handle3);

%define two points x1 = 0, x2 =
% note x 1 + y 2 + m3 3 = 0
% y = (-m3 3 - x 1 ) / 2

x1 = ones(n_plots,1) * -20000;
%    y1 = - (el2(:,3) * m3) ./el2(:,2);
y1 = (- (el2(:,3) * m3) - (x1(:) .* el2(:,1))) ./el2(:,2);

x2 = ones(n_plots,1) * 20000;
y2 = (- (el2(:,3) * m3) - (x2(:) .* el2(:,1))) ./el2(:,2);

hold on
a = [x1,x2]';
b = [ y1,y2 ]';
%    plot(x1,y1, 'g+');
line(a,b,'Color','r');

hold off

%end```