To retrieve height and width of more than one rectangle rectangle drawn and store it in a matrix

Hi Guys I am drawing rectangle in an image using following code

[L Ne]=bwlabel(BW2);
propied=regionprops(L,'BoundingBox');
hold on
for x=1:size(propied,1)
  rectangle('Position',propied(x).BoundingBox,'EdgeColor','g','LineWidth',2)
end
hold off

Now if there are two rectangles formed in my image and I want to know their height, width, start and end point and store it in a matrix. (data Of both the rectangles)

I dont know how to do that. plz help me.

[Karan Ratnaparkhi]

I tried findall function bt it didnt wrk.

[Jan]

How did you try to use FINDALL and what exactly means "didn't work"? Please post the code and the error message or description of the different between the results and your expectations.

Answer 1

[Jan]

hold on
RectH = zeros(1, 10);
for x = 1:10
  rectangle('Position', (rand(1, 4) * 0.5), ...
            'Tag', 'myRect');
end

Different methods to get the Positions:

Use the vector of handles, if it is available already:

PosList = get(RectH, 'Position');

If you have the AXES handle only:

RectH = findobj(allchild(AxesH), 'flat', 'Type', 'rectangle');

Or:

RectH = findobj(allchild(AxesH), 'flat', 'Tag', 'myRect');

If you have the FIGURE handle only:

RectH = findobj(allchild(FigH), 'Tag', 'myRect');

Answer 2

[Karan Ratnaparkhi]

Hey Jan Simon there are 3 rectangles formed in my image and i hav 2 get d positions of each of them and store the whole data in an array. Findobj finds d first rectangle it encounters and even if i am running a for loop for all rectangles i am getting position of first rectangle only, in array! Is der ny method to increment findobj to go for the next rectangle?

[Karan Ratnaparkhi]

After the rectangles are drawn using above code my nxt code is

Q=zeros(Ne,4);

for i=1:Ne

rects = findobj(allchild(gca), 'flat', 'Type', 'rectangle');

%rects = findall(gcf,'type','rectangle');

for K = 1:length(rects)

for x=1:Ne

for y=1:4

rpos = get(rects(K),'Position');

fprintf(1, 'Rectangle #%d: height %g, width %g at (%g,%g)\n', ...

rpos(3), rpos(4), rpos(1), rpos(2));

Q(x,y)=rpos(y);

end

end

end

end

Q(1:Ne,1:4)

Bt i am getting value in Q as:

19.5000 9.5000 2.0000 1.0000

19.5000 9.5000 2.0000 1.0000

19.5000 9.5000 2.0000 1.0000

19.5000 9.5000 2.0000 1.0000