Fast Marching in 3D¶
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This tour explores the use of Fast Marching methods in 2D.
warning off
addpath('toolbox_signal')
addpath('toolbox_general')
addpath('toolbox_graph')
addpath('solutions/fastmarching_2_3d')
warning on
name = 'vessels';
options.nbdims = 3;
M = read_bin(name, options);
M = rescale(M);
Size of the image (here it is a cube).
n = size(M,1);
Such a volumetric dataset is more difficult to visualize than a standard 2D image. You can render slices along each X/Y/Z direction.
clf;
imageplot(M(:,:,50), 'X/Y slice', 1, 3, 1);
imageplot(squeeze(M(:,50,:)), 'X/Z slice', 1, 3, 2);
imageplot(squeeze(M(50,:,:)), 'Y/Z slice', 1, 3, 3);
We can display some horizontal slices.
slices = round(linspace(10,n-10,4));
clf;
for i=1:length(slices)
s = slices(i);
imageplot( M(:,:,s), strcat(['Z=' num2str(s)]), 2,2,i );
end
You can also perform a volumetric rendering. In order to do so, you need to set up a correct alpha mapping to make transparent some parts of the volume. Here, each time the options.center value is increased.
clf;
h = vol3d('cdata',M,'texture','2D');
view(3); axis off;