Tutorial_of_video_tracking_JEELAB/step4_extract_image_statistics.m

% Directory setting
frame_directory = 'data/frames/';
mask_directory = 'data/predicts/';
video_names = dir( [frame_directory 'sample*'] );

% Enhancing figure visibility
set(gcf, 'Position', [0 0 800 800], 'Color', [1 1 1] );

% Figure to video 
output_video_option = 1;
if output_video_option
    output_video_directory = 'data/output/';
    if ~isdir(output_video_directory), mkdir(output_video_directory); end
end

% Main loop
for videoIdx = 1:length( video_names )
    frame_names = dir( [frame_directory video_names(videoIdx).name '/*.jpg']);
    mask_names = dir( [mask_directory video_names(videoIdx).name '/*.jpg']);
    
    %% For one video
    xy = nan([2,length( frame_names )]);
    bb = nan([4,length( frame_names )]);
    for frameIdx = 1:length( frame_names )
        
        %% Single frame loading
        frame_name = [ frame_names(frameIdx).folder ...
            '/' frame_names(frameIdx).name];
        mask_name = [ mask_names(frameIdx).folder ...
            '/' mask_names(frameIdx).name];
        
        frame = double(imread( frame_name ))/255; % Scaling to 0-1
        mask = double(imread( mask_name ))/255; % Scaling to 0-1
        
        % Manual artifact rejection
        mask(:,1:30) = 0;

        % Visualization
        
        % Original frame
        sp1 = subplot(2,2,1); hold off
        imagesc( frame );
        set(gca, 'Box', 'off', 'LineWidth', 2, 'XTick', [], 'YTick', [], 'FontSize', 15);
        title( sprintf( '(1) Frame #%04d', frameIdx ));
        colormap(sp1, 'gray');
        
        % Mask 
        sp2 = subplot(2,2,2); hold off
        imagesc( mask' );
        set(gca, 'Box', 'off', 'LineWidth', 2, 'XTick', [], 'YTick', [], 'FontSize', 15);
        title( sprintf( '(2) Mask #%04d', frameIdx ));
        colormap(sp2, 'gray');
        
        % Overlay
        overlay = repmat( frame, [1 1 3] );
        overlay(:,:,1) = 0.5*mask';
        
        sp3 = subplot(2,2,3); hold off
        imagesc( overlay );
        set(gca, 'Box', 'off', 'LineWidth', 2, 'XTick', [], 'YTick', [], 'FontSize', 15);
        title( sprintf( '(3) Overlay #%04d', frameIdx ));
        
        %% Extracting image statistics using regionprops
        mask_binary = mask > probability_threshold;
        stats = regionprops( mask_binary', 'BoundingBox', 'Area', 'Centroid', 'Orientation' );
        
        probability_threshold = 0.5; % Probability, anonymous unit (0-1)
        size_threshold = 100; % Pixel
        drawing_regionprops = false;
        
        big_enough = find( [stats.Area]>size_threshold );
        if ~isempty( big_enough )
            stat = stats(big_enough);
            xy(:,frameIdx) = stat.Centroid;
            bb(:,frameIdx) = stat.BoundingBox;
        else % if failed
            xy(:,frameIdx) = xy(:,frameIdx-1);
            bb(:,frameIdx) = bb(:,frameIdx-1);
        end
            
        sp4 = subplot(2,2,4); hold off
        imagesc( frame );
        set(gca, 'Box', 'off', 'LineWidth', 2, 'XTick', [], 'YTick', [], 'FontSize', 15);
        title( sprintf( '(4) Tracking result #%04d', frameIdx ));
        colormap(sp4,'gray');
        hold on;
        % Centroid
        plot( xy(1,frameIdx), xy(2,frameIdx), 'g*', 'MarkerSize', 20);
        % BoundingBox
        rectangle('Position', bb(:,frameIdx),'EdgeColor','g','LineWidth',2 )
        % Text annotation
        text_contents = sprintf( 'X: [%.1f], Y: [%.1f]',  xy(:,frameIdx));
        text( xy(1,frameIdx),xy(2,frameIdx) - 50, text_contents, 'Color', 'g',...
            'HorizontalAlignment', 'center' );
        
        %% Etc.
        drawnow;
        
        % Writing output video
        if output_video_option
            if frameIdx==1
                try vid_obj.close(); clear vid_obj; end
                vid_obj = VideoWriter( [output_video_directory ...
                    video_names(videoIdx).name '.mp4'], 'MPEG-4');
                vid_obj.open();
            end
            capture_frame = getframe(gcf);
            vid_obj.writeVideo(capture_frame.cdata);
            if frameIdx==length( frame_names )
                vid_obj.close();
            end
        end
    end
end