How to overlay original image with created filled circle?

Dear All,

I have following shape:

And I want to draw a filled circle above it (make a mask for this circle). I have tried following code, but it didn't work as I expected:

close all;clc; clear all;
original=imread('SA_r1.jpg'); % original=imread('u.jpg');
original=imresize(original,[500 500],'bicubic');% simple image interpolation.
bi= im2bw(original); % bi(binary image)

hbw = bwconvhull(bi);
[Clab, ~] = bwlabel(hbw);
st = regionprops(Clab,'Centroid','BoundingBox','Orientation','MajorAxisLength','MinorAxisLength');
figure; imshow(original);   hold on;
xmin=floor(st.BoundingBox(1)); ymin=floor(st.BoundingBox(2));
xmax=floor(st.BoundingBox(1)+st.BoundingBox(3)); ymax=floor(st.BoundingBox(2)+st.BoundingBox(4));

figure; imshow(hbw,[]); hold on; sp_mean=15;

r1=floor(ymin-sp_mean); r2=floor(ymax+sp_mean);c1=floor(xmin-sp_mean);c2=floor(xmax+sp_mean);
rectangle('Position',[xmin-sp_mean, ymin-sp_mean, st.BoundingBox(3)+2*sp_mean, st.BoundingBox(4)+2*sp_mean], 'Curvature',[1,1],'FaceColor','w');

figure; 
original(c1:c2,r1:r2)=rectangle('Position',[xmin-sp_mean, ymin-sp_mean, st.BoundingBox(3)+2*sp_mean, st.BoundingBox(4)+2*sp_mean], 'Curvature',[1,1],'FaceColor','w');
imshow(original); contour(original, [0,0], 'r');

Here is the results I have:

So I want to overlay original image with created filled circle and draw a contour of it.

Thanks for any help!

Answer 1

[Image Analyst]

I don't understand. What does "above it" mean to you: inteh overlay, or at a lower line number? And what does a contour mean when you're talking about a binary image? Do you want a transparent image in the overlay, like this: http://blogs.mathworks.com/steve/2009/02/18/image-overlay-using-transparency/ or this: http://www.mathworks.com/matlabcentral/answers/104889-how-to-overlay-a-foreground-image-over-a-background-image

[Ivan Shorokhov]

@Image Analyst, I want to make white circle part of the image. So it will be white circle(0) in black background(255). Right now it is only filled circle with white color.

And want to know, how I can do it (burn it or mask it or overlay it).

[Image Analyst]

See attached demos.

[Ivan Shorokhov]

@Image Analyst Thank you.