How to draw single bounding box by combining all bounding boxes

Hello everyone, I hope you are doing well. I have the image in which i want to draw bounding box on the object.

I have write the following code, which convert the image in binary form and draw the bounding box around white object.

But i want to draw a single bounding box. How can i draw or combine all bounding boxes in MATLAB and plot it on original Image.

Image=imread('GFSK.png')
im1=im2bw(Image);
invertedI = ~im1
[labeledImage, numRegions] = bwlabel(invertedI);
props = regionprops(labeledImage,'all' );
allLengths = [props.Area];
% NumberofPulses=allLengths;
centroids = vertcat(props.Centroid);


figure;
hold on;
for k = 1 : numRegions
    y1 = round(centroids(k, 2));
    y2 = y1;
	xt = props(k).Centroid(1);
	yt = props(k).Centroid(2);
    BB = props(k).BoundingBox;
    
	

	
    rectangle('Position', [BB(1),BB(2),BB(3),BB(4)],'EdgeColor','b','LineWidth',1) ;
    


    caption = sprintf('Class 1') ;
    hold off
    title(caption, 'FontSize',10);
end

Answer 1

[KSSV]

Image=imread('https://in.mathworks.com/matlabcentral/answers/uploaded_files/1107335/GFSK.png') ;
im1=im2bw(Image);
invertedI = ~im1 ;
[labeledImage, numRegions] = bwlabel(invertedI);
props = regionprops(labeledImage,'all' );
allLengths = [props.Area];
% NumberofPulses=allLengths;
centroids = vertcat(props.Centroid);

X = zeros(numRegions,4) ;
Y = zeros(numRegions,4) ;
figure;
hold on;
for k = 1 : numRegions
    y1 = round(centroids(k, 2));
    y2 = y1;
    xt = props(k).Centroid(1);
    yt = props(k).Centroid(2);
    BB = props(k).BoundingBox;
    
    rectangle('Position', [BB(1),BB(2),BB(3),BB(4)],'EdgeColor','b','LineWidth',1) ;
    X(k,:) = [BB(1) BB(1)+BB(3) BB(1)+BB(3) BB(1)] ;
    Y(k,:) = [BB(2) BB(2) BB(2)+BB(4) BB(2)+BB(4)] ;
    
    caption = sprintf('Class 1') ;
    hold off
    title(caption, 'FontSize',10);
end
x0 = min(X(:)) ; x1 = max(X(:)) ;
y0 = min(Y(:)) ; y1 = max(Y(:)) ;
L = abs(x1-x0) ;
B = abs(y1-y0) ;
rectangle('Position', [x0 y0 L B],'EdgeColor','r','LineWidth',1) ;

[Stephen john]

@KSSV Thanks How to draw this box on original image. and write string as class1

[KSSV]

Image=imread('https://in.mathworks.com/matlabcentral/answers/uploaded_files/1107335/GFSK.png') ;
im1=im2bw(Image);
invertedI = ~im1 ;
[labeledImage, numRegions] = bwlabel(invertedI);
props = regionprops(labeledImage,'all' );
allLengths = [props.Area];
% NumberofPulses=allLengths;
centroids = vertcat(props.Centroid);

X = zeros(numRegions,4) ;
Y = zeros(numRegions,4) ;
figure;
hold on;
for k = 1 : numRegions
    y1 = round(centroids(k, 2));
    y2 = y1;
    xt = props(k).Centroid(1);
    yt = props(k).Centroid(2);
    BB = props(k).BoundingBox;
    
    % rectangle('Position', [BB(1),BB(2),BB(3),BB(4)],'EdgeColor','b','LineWidth',1) ;
    X(k,:) = [BB(1) BB(1)+BB(3) BB(1)+BB(3) BB(1)] ;
    Y(k,:) = [BB(2) BB(2) BB(2)+BB(4) BB(2)+BB(4)] ;
       
end
x0 = min(X(:)) ; x1 = max(X(:)) ;
y0 = min(Y(:)) ; y1 = max(Y(:)) ;
L = abs(x1-x0) ;
B = abs(y1-y0) ;
imshow(Image) 
hold on
rectangle('Position', [x0 y0 L B],'EdgeColor','k','LineWidth',1) ;
caption = sprintf('Class 1') ;
title(caption, 'FontSize',10);

[Stephen john]

@KSSV Not as Title .Text should be Near to Bounding box coordinates

[KSSV]

This is easy..you can do it. Read about text

[Stephen john]

@KSSV i am unable to do that , thats why i asked

[Walter Roberson]

text(x0, y0, 'class1')