How to detect hand?

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Explorer on 19 Jan 2014
Commented: Image Analyst on 29 Sep 2018
MATLAB CODE (also attached):
clear all; close all; clc image=imread('a_ASL3.jpg'); BW=binary_image(image); BW = ~BW; st = regionprops(BW, 'BoundingBox' ); for k = 1 : length(st) thisBB = st(k).BoundingBox; rectangle('Position', [thisBB(1),thisBB(2),thisBB(3),thisBB(4)],... 'EdgeColor','r','LineWidth',2 ) end
PROBLEM I want bounding box just around hand so that I can crop it and do further operations but I am getting image as output in which there are bounding box around every object.
  1 Comment
Poornima Gokhale
Poornima Gokhale on 14 Dec 2015
I tried this code for my image.But its not working properly. How to modify?? And i want an enlarged image of individual letter to save that letter. Please help me

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Accepted Answer

Image Analyst
Image Analyst on 19 Jan 2014
Try this:
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;
% Read in a color demo image.
folder = 'C:\Users\Explorer\Documents';
baseFileName = 'a_ASL3.jpg';
% Get the full filename, with path prepended.
fullFileName = fullfile(folder, baseFileName);
if ~exist(fullFileName, 'file')
% Didn't find it there. Check the search path for it.
fullFileName = baseFileName; % No path this time.
if ~exist(fullFileName, 'file')
% Still didn't find it. Alert user.
errorMessage = sprintf('Error: %s does not exist.', fullFileName);
% Get the dimensions of the image.
% numberOfColorBands should be = 1.
[rows, columns, numberOfColorBands] = size(grayImage);
if numberOfColorBands > 1
% It's not really gray scale like we expected - it's color.
% Convert it to gray scale by taking only the green channel.
grayImage = grayImage(:, :, 2); % Take green channel.
% Display the original gray scale image.
subplot(2, 2, 1);
imshow(grayImage, []);
axis on;
title('Original Grayscale Image', 'FontSize', fontSize);
% Enlarge figure to full screen.
set(gcf, 'Units', 'Normalized', 'OuterPosition', [0 0 1 1]);
% Give a name to the title bar.
set(gcf, 'Name', 'Demo by ImageAnalyst', 'NumberTitle', 'Off')
binaryImage = grayImage < 128;
% Display the image.
subplot(2, 2, 2);
imshow(binaryImage, []);
title('Binary Image', 'FontSize', fontSize);
% Label the image
labeledImage = bwlabel(binaryImage);
measurements = regionprops(labeledImage, 'BoundingBox', 'Area');
for k = 1 : length(measurements)
thisBB = measurements(k).BoundingBox;
rectangle('Position', [thisBB(1),thisBB(2),thisBB(3),thisBB(4)],...
'EdgeColor','r','LineWidth',2 )
% Let's extract the second biggest blob - that will be the hand.
allAreas = [measurements.Area];
[sortedAreas, sortingIndexes] = sort(allAreas, 'descend');
handIndex = sortingIndexes(2); % The hand is the second biggest, face is biggest.
% Use ismember() to extact the hand from the labeled image.
handImage = ismember(labeledImage, handIndex)
% Now binarize
handImage = handImage > 0;
% Display the image.
subplot(2, 2, 3);
imshow(handImage, []);
title('Hand Image', 'FontSize', fontSize);
Image Analyst
Image Analyst on 29 Sep 2018
From my code
width = thisBB(3)
height = thisBB(4)

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More Answers (1)

Ranjitha on 7 Sep 2015
How to find the length and width for the given code.?? please do help with this.. Can you please let me know what all changes has to be made for the existing code to find length and width of the hand image.

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