how to detect hand from an image ?

I have to detect hand from an image. First when I tried this code that is given in below link: https://www.mathworks.com/matlabcentral/answers/112917-how-to-detect-hand then it detect my hand with an arm area as shown in given figure. Can you please tell me how can I detect hand from an arm.

Here is the code:

    folder=('C:\Users\Tayaba Abro\Desktop');
    baseFileName=('hand.jpg');
    fullFileName=fullfile(folder,baseFileName);
    format long g;
    format compact;
    fontSize = 20;

    %IMAGE SEGMENTATION
    img=imread(fullFileName);
    img=rgb2ycbcr(img);
    for i=1:size(img,1)
        for j= 1:size(img,2)
            cb = img(i,j,2);
            cr = img(i,j,3);
            if(~(cr > 132 && cr < 173 && cb > 76 && cb < 126))
                img(i,j,1)=235;
                img(i,j,2)=128;
                img(i,j,3)=128;
            end
        end
    end
    img=ycbcr2rgb(img);
    subplot(2,2,1);
    image1=imshow(img);
    axis on;
    title('Skin Segmentation', 'FontSize', fontSize);
    set(gcf, 'Units', 'Normalized', 'OuterPosition', [0 0 1 1]);

    %SEGMENTED IMAGE TO GRAYIMAGE
    grayImage=rgb2gray(img);
    subplot(2,2,2);
    image2=imshow(grayImage);
    axis on;
    title('Original Grayscale Image', 'FontSize', fontSize);
    set(gcf, 'Units', 'Normalized', 'OuterPosition', [0 0 1 1]);

    %GRAY TO BINARY IMAGE
    binaryImage = grayImage < 245;
    subplot(2, 2, 3);
    axis on;
    image3=imshow(binaryImage, []);
    title('Binary Image', 'FontSize', fontSize);

    % Label the image 
    labeledImage = bwlabel(binaryImage);  % label the connected components in an image and assigning each one a unique label
    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 )
    end

    % 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, 4);
    image4=imshow(handImage, []);
    title('Hand Image', 'FontSize', fontSize);

[Image Analyst]

No, no one can, because you forgot to attach 'hand.jpg'.

Answer 1

[Tayyaba Abro]

Answer 2

[jue xi]

hi i need to detect hand from image too. but after that i need to calculate the length of hand. does anyone know how to get the measurement? any steps of function i can use?