Hi, how to accumulate total number of cars detection and reset to zero at specified time period in "Detecting Cars Using Gaussian Mixture Models"?

clear

foregroundDetector = vision.ForegroundDetector('NumGaussians', 3, ... 'NumTrainingFrames', 50);

videoReader = vision.VideoFileReader('visiontraffic.avi'); for i = 1:150 frame = step(videoReader); foreground = step(foregroundDetector, frame); end

total=0; figure; imshow(frame); title('Video Frame');

figure; imshow(foreground); title('Foreground');

se = strel('square', 3); filteredForeground = imopen(foreground, se); figure; imshow(filteredForeground); title('Clean Foreground');

blobAnalysis = vision.BlobAnalysis('BoundingBoxOutputPort', true, ... 'AreaOutputPort', false, 'CentroidOutputPort', false, ... 'MinimumBlobArea', 150); bbox = step(blobAnalysis, filteredForeground);

result = insertShape(frame, 'Rectangle', bbox, 'Color', 'green');

numCars= size(bbox, 1);
result = insertText(result, [100 100], total, 'BoxOpacity', 1, ...
  'FontSize', 14);
figure; imshow(result); title('Detected Cars');

videoPlayer = vision.VideoPlayer('Name', 'Detected Cars'); videoPlayer.Position(3:4) = [650,400]; % window size: [width, height] se = strel('square', 3);

while ~isDone(videoReader)

    frame = step(videoReader); % read the next video frame

    foreground = step(foregroundDetector, frame);

    filteredForeground = imopen(foreground, se);

    bbox = step(blobAnalysis, filteredForeground);

    result = insertShape(frame, 'Rectangle', bbox, 'Color', 'green');
    numCars = size(bbox, 1);

    for i=1:1:numCars
             total=total+bbox(i);

      end

     result = insertText(result, [10 10], total, 'BoxOpacity', 1, ...
        'FontSize', 14); 

    step(videoPlayer, result);

end