Motion Detection using Camshift algorithm Matlab code

There are two files included.

1.convert video frames using this .m file

clc;
cd frames;

for i = 2:107,
    filename1 = sprintf('%3.3i.png', i);
    filename2 = sprintf('%3.3i.png', i-1);
    A = imread(filename1, 'png');
    A = RGB2GRAY(A);
 
    B = imread(filename2, 'png');
    B = RGB2GRAY(B);
 
    C = imabsdiff(A,B);
    C = medfilt2(C, [5 5]);
    imwrite(C, sprintf('Frame %4.4d.png', i), 'png');
end

cd ..

disp('Done.');

2. Camshift.m

clc;
disp('Running...');
close all;
clear;
cd frames;

    WHITE = 255;

    % Threshold of convergence (in pixels for each deg. of freedom)
T = 1;
 
    % Number of pixels to expand search window by.
    P = 5;

avi = avifile('output1.avi');

% Initial search window size.
%W = [10 10];
W = [99 99];

% Initial location of search window.
%L = [95 193];
L = [71 141];

% For plotting motion
Xpoints=[];
Ypoints=[];

disp('Frame: Coordinates');

for frame = 1:44,
filename = sprintf('%3.3i.png', frame);
R = imread(filename, 'png');

% Convert image from RGB space to HSV space
I = rgb2hsv(R);

% Extract the hue information
I = I(:,:,1);
    I = roicolor(I, 0.83, 1.0);
 
    % Initialization
    oldCamL = [0 0];
    MeanConverging = 1;

    for i = L(1) : L(1)+W(1),
        x = i;
        y = L(2);
        if x > size(I,1) | y > size(I,2) | x < 1 | y < 1
            continue;
        else
            R(x, y,:) = 0;
        end
    end
 
    for i = L(1) : L(1)+W(1),
        x = i;
        y = L(2) + W(2);
        if x > size(I,1) | y > size(I,2) | x < 1 | y < 1
            continue;
        else
            R(x, y, :) = 0;
        end
    end  
 
    for i = L(2) : L(2)+W(2),
        x = L(1);
        y = i;
        if x > size(I,1) | y > size(I,2) | x < 1 | y < 1
            continue;
        else
            R(x, y, :) = 0;
        end
    end  

    for i = L(2) : L(2)+W(2),
        x = L(1)+W(1);
        y = i;
        if x > size(I,1) | y > size(I,2) | x < 1 | y < 1
            continue;
        else
            R(x, y, :) = 0;
        end
    end  

M00 = 0.0;
for i = L(1)-P : (L(1)+W(1)+P),
            for j = L(2)-P : (L(2)+W(2)+P),
                if i > size(I,1) | j > size(I,2) | i < 1 | j < 1
                    continue;
                end
                M00 = M00 + double(I(i,j));
            end
end

M10 = 0.0;
for i = L(1)-P : (L(1)+W(1)+P),
            for j = L(2)-P : (L(2)+W(2)+P),
                if i > size(I,1) | j > size(I,2) | i < 1 | j < 1
                    continue;
                end
                M10 = M10 + i * double(I(i,j));
            end
end

M01 = 0.0;
for i = L(1)-P : (L(1)+W(1)+P),
            for j = L(2)-P : (L(2)+W(2)+P),
                if i > size(I,1) | j > size(I,2)| i < 1 | j < 1
                    continue;
                end              
                M01 = M01 + j * double(I(i,j));
            end
end

xc = round(M10 / M00);
yc = round(M01 / M00);

oldL = L;
L = [floor(xc - (W(1)/2)) floor(yc - (W(2)/2))];
     
        % Check threshold
        if abs(oldL(1)-L(1)) < T | abs(oldL(2)-L(2)) < T
            MeanConverging = 0;
        end
    end
 
    s = round(1.1 * sqrt(M00));
    W = [ s      floor(1.2*s) ];
    L = [floor(xc - (W(1)/2)) floor(yc - (W(2)/2))];
 
    % Output the centroid's coordinates
    disp(sprintf('%3i:   %3i, %3i', frame, xc, yc));
    Xpoints = [Xpoints xc];
    Ypoints = [Ypoints yc];
 
    % Superimpose plus sign on to centroid of hand.
    plus_sign_mask = [0 0 0 0 0 0 1 0 0 0 0 0 0;
                     0 0 0 0 0 0 1 0 0 0 0 0 0;
                     0 0 0 0 0 0 1 0 0 0 0 0 0;
                     0 0 0 0 0 0 1 0 0 0 0 0 0;
                     0 0 0 0 0 0 1 0 0 0 0 0 0;
                     0 0 0 0 0 0 1 0 0 0 0 0 0;
                     1 1 1 1 1 1 1 1 1 1 1 1 1;
                     0 0 0 0 0 0 1 0 0 0 0 0 0;
                     0 0 0 0 0 0 1 0 0 0 0 0 0;
                     0 0 0 0 0 0 1 0 0 0 0 0 0;
                     0 0 0 0 0 0 1 0 0 0 0 0 0;
                     0 0 0 0 0 0 1 0 0 0 0 0 0;
                     0 0 0 0 0 0 1 0 0 0 0 0 0];
sizeM = size(plus_sign_mask);
for i = -floor(sizeM(1) / 2):floor(sizeM(1) / 2),
        for j = -floor(sizeM(2) / 2):floor(sizeM(2) / 2),
            if plus_sign_mask(i+1+floor(sizeM(1) / 2), j+1+floor(sizeM(2) / 2)) == 1
                R(i+xc, j+yc, :) = WHITE;
            end
        end
end
% ----------------------------------------------------------------------
    % Display the probability image.
    I = rgb2hsv(R);
    S = [];
    S(:,:,1) = I(:,:,1);
    S(:,:,2) = I(:,:,1);  
    S(:,:,3) = I(:,:,1);
% Extract the hue information
    avi = addframe(avi, S);
 
end
disp('AVI move parameters:');
avi = close(avi)
plot(Ypoints,Xpoints, 'go' , Ypoints, Xpoints);
axis([0 320 0 240]);
cd ..
disp('Done.');