Coffee Model - Video Processing

ConcentrationChange.m

Getting a file reader of the video, along with the numer of frames

reader = mmreader('Trial1.avi');
numFrames=get(reader,'numberOfFrames');

Setting the thershold values

binaryThresh = 70;
areaThresh = 150;

Looping through all of the frames

maxArea = zeros(1,numFrames);
for i = 1:numFrames

frame = read(reader,i);

Image Processing on the frame.

The frame is broken up into the red, green, and blue components

r = frame(:,:,1);
    g = frame(:,:,2);
    b = frame(:,:,3);
    % A net frame is computed, which only has the red pixels
    net = r - g - b;
    % Thresholding the image

    bw = net > binaryThresh;
    % Creating a component map baseed on area
    cc =  bwconncomp(bw,4);
    stats = regionprops(cc,'Area');
    if isempty(stats) || isempty(fieldnames(stats))
        fprintf(1,'Empty Stats structure at frame %d.\n',i);
        break;
    else

        % Creating an index of all areas greater than the threshold
        idx = find([stats.Area]>areaThresh);
        bw2 = ismember(labelmatrix(cc),idx);
        maxArea(i)= max([stats.Area]);
    end

Empty Stats structure at frame 476.

end

plot(maxArea);
xlabel('Frame (t)');
ylabel('Area (conenctration)');
title('Concentration Evolution');