Adding a title to a roipoly image

I'd like to put a title or caption on the figure displayed by the roipoly function so that users know what to do when the image comes up. I haven't been able to do it with any title method I know of for regular figures and graphs, and every search I've done has turned up completely empty. Is there a way to do this, or does MATLAB not support it?

[Sulimon Sattari]

What version of MATLAB are you running? This worked fine for me in R2012a

I = imread('eight.tif');
c = [222 272 300 270 221 194];
r = [21 21 75 121 121 75];
BW = roipoly(I,c,r);
figure, imshow(I)
figure, imshow(BW)
figure(2)
title('hello')
figure(1)
title('hello1')

Answer 1

[Image Analyst]

Do not pass the image to roipoly(). Use text() or title() to put up instructions. Also you may want to consider roipolyold() - a more streamlined version that doesn't require confirmation. Try this:

fontSize = 16;
I = imread('eight.tif');
imshow(I);
% Enlarge figure to full screen.
set(gcf, 'units','normalized','outerposition',[0 0 1 1]);

message = sprintf('Click the vertices.\nRight click to finish and close polygon.\nDouble-click inside polygon to accept it.');
% Display instructions as title.
title(message, 'FontSize', fontSize);
text(10,10,message);
uiwait(msgbox(message));
% Unfortunately everything disappears when you run roipoly.
BW = roipoly();
subplot(1, 2, 1);
imshow(I)
subplot(1, 2, 2);
imshow(BW)

[Victoria]

The idea was to keep the message from disappearing when I run roipoly. Is there a way to do that?

[Image Analyst]

Not that I'm aware of. You could use a static text label instead of using the title. That would probably stick around.