Math Forum Discussions

Sanjeev

Posts: 4
Registered: 12/27/12

MATLAB Moving Object detction
Posted: Jan 2, 2013 7:13 AM

Plain Text

Can any1 help me with my code? i cant get the moving object output to the real time input. I jst get a colored empty screen
function realVideo()

% Define frame rate
NumberFrameDisplayPerSecond=25;

% Open figure
hFigure=figure(1);

% Set-up webcam video input
source= videoinput('winvideo');

% Set parameters for video Acquire only one frame each time
set(source,'FramesPerTrigger',1);
% Go on forever until stopped
set(source,'TriggerRepeat',Inf);
% Get a RGB image
set(source,'ReturnedColorSpace','RGB');
triggerconfig(source, 'Manual');

% set up timer object
TimerData=timer('TimerFcn', {@FrameRDisplay,source},'Period',1/NumberFrameDisplayPerSecond,'ExecutionMode','fixedRate','BusyMode','drop');

% Start video and timer object
start(source);
start(TimerData);

% We go on until the figure is closed
uiwait(hFigure);

% Clean up everything
stop(TimerData);
delete(TimerData);
stop(source);
delete(source);
% clear persistent variables
clear functions;
end

function FrameRDisplay(obj, event,source)
persistent IM;
trigger(source);
IM=getdata(source,1,'uint8');
subplot(2,1,1);
imagesc(IM);
bg = getsnapshot(source(1)); % read in 1st frame as background frame
bg_bw = rgb2gray(bg); % convert background to greyscale

% ----------------------- set frame size variables -----------------------
fr_size = size(bg);
width = fr_size(2);
height = fr_size(1);
f = zeros(height, width);
%f2 = zeros(height, width);

% --------------------- process frames -----------------------------------

for i = 2:3:(length(source)-1)

fr1 = source(i-1).cdata; % read in frame-i-1
fr_bw1 = rgb2gray(fr1); % convert frame-i-1 to grayscale
fr2 = source(i).cdata; % read in frame-i
fr_bw2 = rgb2gray(fr2); % convert frame-i to grayscale
fr3 = source(i+1).cdata; % read in frame-i+1
fr_bw3 = rgb2gray(fr3); % convert frame-i+1 to grayscale

fr_diff1 = abs(double(fr_bw1) - double(fr_bw2)); % First frame Difference cast operands as double to avoid negative overflow
fr_diff2 = abs(double(fr_bw2) - double(fr_bw3)); % Second frame difference cast operands as double to avoid negative overflow

if ((fr_diff1(k,j) > thresh) && (fr_diff2(k,j) > thresh))
f(k,j) = 255;
else
f(k,j) = 0;

end

end

subplot(2,1,2);
imagesc(uint8(f));
title('MOVING OBJECT');
end