help with regionprops in order to draw boundary

i have the following image

and I am using this code to draw a bounding box around the image

img=imread('li.jpg');
% figure(1)
imshow(img);
img=rgb2gray(img);
threshold = graythresh(img);
img =~im2bw(img,threshold);
 img = bwareaopen(img,30);
pause(1)

imshow(~img);
[L Ne]=bwlabel(img);
regProp=regionprops(L,'BoundingBox');
hold on
for n=1:size(regProp,1)
    rectangle('Position',regProp(n).BoundingBox,'EdgeColor','r','LineWidth',2)
end
hold off
pause (1)
figure
for n=1:Ne
    [r,c] = find(L==n);
    n1=img(min(r):max(r),min(c):max(c));
    figure;
    imshow(~n1);

     saveas(figure(n),fullfile('C:\SegmentedCharacters',['figure' num2str(n) '.jpg']));
  end

but i am unable to do so. Could anyone help me out? Thank you.

Answer 1

[Image Analyst]

There were lots of fixes that needed to be made. Here is the fixed code:

% Initialization steps.
clc;    % Clear the command window.
close all;  % Close all figures (except those of imtool.)
clear;  % Erase all existing variables. Or clearvars if you want.
workspace;  % Make sure the workspace panel is showing.
format long g;
format compact;
fontSize = 20;

grayImage = imread('li.jpg');
% Display the image.
subplot(3, 3, 1);
imshow(grayImage);
axis on;

% Get the dimensions of the image.  Convert to gray scale if it's more than 1 color channel.
% numberOfColorChannels should be = 1 for a gray scale image, and 3 for an RGB color image.
[rows, columns, numberOfColorChannels] = size(grayImage);
if numberOfColorChannels > 1
  % It's not really gray scale like we expected - it's color.
  % Use weighted sum of ALL channels to create a gray scale image.
  grayImage = rgb2gray(grayImage); 
end
% Crop off white surround
grayImage = grayImage(321:472, 97:1104);
subplot(3, 3, 2);
imshow(grayImage);
axis on;

% Set up figure properties:
% Enlarge figure to full screen.
set(gcf, 'Units', 'Normalized', 'OuterPosition', [0 0 1 1]);
% Get rid of tool bar and pulldown menus that are along top of figure.
set(gcf, 'Toolbar', 'none', 'Menu', 'none');
% Give a name to the title bar.
set(gcf, 'Name', 'Demo by ImageAnalyst', 'NumberTitle', 'Off')

% Let's compute and display the histogram.
[pixelCount, grayLevels] = imhist(grayImage);
subplot(3, 3, 3); 
bar(grayLevels, pixelCount); % Plot it as a bar chart.
grid on;
title('Histogram of original image', 'FontSize', fontSize, 'Interpreter', 'None');
xlabel('Gray Level', 'FontSize', fontSize);
ylabel('Pixel Count', 'FontSize', fontSize);
xlim([0 grayLevels(end)]); % Scale x axis manually.

% threshold = graythresh(grayImage); % Bad for a JPG image
threshold = 200;
mask = grayImage > threshold;
% Get rid of small blobs
mask = bwareaopen(mask, 50);
subplot(3, 3, 3);
imshow(mask);
axis on;
[labeledImage, numberOfRegions] = bwlabel(mask);
props = regionprops(labeledImage,'BoundingBox');
hold on
for n = 1 : numberOfRegions
  rectangle('Position',props(n).BoundingBox, 'EdgeColor','r', 'LineWidth',2)
end
hold off

% Crop regions and save them.
folder = 'C:\SegmentedCharacters';
for n = 1 : numberOfRegions
  croppedImage = imcrop(mask, props(n).BoundingBox);
  subplot(3, 3, n+3);
  imshow(croppedImage);
  axis on;
  % Save to disk
  baseFileName = sprintf('figure %d.png', n);
  fullFileName = fullfile(folder, baseFileName)
  imwrite(croppedImage, fullFileName);
end

[shru s]

Thank you so much for your help. You are awesome!