private Bitmap ProcessImage(SequenceReader reader)
        {
            // set up the face model
            var root      = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, @"..\..\");
            var faceModel = new FaceModelParameters(root, false);

            faceModel.optimiseForImages();

            // set up a face detector, a landmark detector, and a face analyser
            var faceDetector     = new FaceDetector();
            var landmarkDetector = new CLNF(faceModel);
            var faceAnalyser     = new FaceAnalyserManaged(root, true, 0);

            // read the image from the sequence reader
            var frame     = new RawImage(reader.GetNextImage());
            var grayFrame = new RawImage(reader.GetCurrentFrameGray());

            // detect faces
            var faces       = new List <Rect>();
            var confidences = new List <double>();

            faceDetector.DetectFacesHOG(faces, grayFrame, confidences);

            // detect landmarks
            var image = frame.ToBitmap();

            foreach (var face in faces)
            {
                landmarkDetector.DetectFaceLandmarksInImage(grayFrame, face, faceModel);
                var points = landmarkDetector.CalculateAllLandmarks();

                // calculate action units
                var features = faceAnalyser.PredictStaticAUsAndComputeFeatures(grayFrame, points);

                // find the action units
                var actionUnits = (from au in features.Item2
                                   where au.Value > 0
                                   orderby au.Key
                                   select au.Key);

                // get top emotions
                var topEmotions = GetTopEmotions(actionUnits);

                // draw the emotion on the face
                using (Graphics g = Graphics.FromImage(image))
                {
                    string name = string.Join(Environment.NewLine, topEmotions);
                    Font   fnt  = new Font("Verdana", 15, GraphicsUnit.Pixel);
                    Brush  brs  = new SolidBrush(Color.Black);
                    var    bump = 36;
                    System.Drawing.SizeF stringSize = g.MeasureString(name, fnt);
                    g.FillRectangle(new SolidBrush(Color.Yellow), (int)face.X + bump, (int)face.Y, stringSize.Width, stringSize.Height);
                    g.DrawString(name, fnt, brs, (int)face.X + bump, (int)face.Y);
                }
            }
            return(image);
        }
        private void ProcessIndividualImages(ImageReader reader)
        {
            // Make sure the GUI is setup appropriately
            SetupFeatureExtractionMode();

            // Indicate we will start running the thread
            thread_running = true;

            // Reload the face landmark detector if needed
            ReloadLandmarkDetector();

            if (!landmark_detector.isLoaded())
            {
                DetectorNotFoundWarning();
                EndMode();
                thread_running = false;
                return;
            }

            // Setup the parameters optimized for working on individual images rather than sequences
            face_model_params.optimiseForImages();

            // Setup the visualization
            Visualizer visualizer_of = new Visualizer(ShowTrackedVideo || RecordTracked, ShowAppearance, ShowAppearance, false);

            // Initialize the face detector if it has not been initialized yet
            if (face_detector == null)
            {
                face_detector = new FaceDetector(face_model_params.GetHaarLocation(), face_model_params.GetMTCNNLocation());
            }

            // Initialize the face analyser
            face_analyser = new FaceAnalyserManaged(AppDomain.CurrentDomain.BaseDirectory, false, image_output_size, MaskAligned);

            // Loading an image file
            var frame      = new RawImage(reader.GetNextImage());
            var gray_frame = new RawImage(reader.GetCurrentFrameGray());

            // For FPS tracking
            DateTime?startTime     = CurrentTime;
            var      lastFrameTime = CurrentTime;

            // This will be false when the image is not available
            while (reader.isOpened())
            {
                if (!thread_running)
                {
                    break;
                }

                // Setup recording
                RecorderOpenFaceParameters rec_params = new RecorderOpenFaceParameters(false, false,
                                                                                       Record2DLandmarks, Record3DLandmarks, RecordModelParameters, RecordPose, RecordAUs,
                                                                                       RecordGaze, RecordHOG, RecordTracked, RecordAligned, true,
                                                                                       reader.GetFx(), reader.GetFy(), reader.GetCx(), reader.GetCy(), 0);

                RecorderOpenFace recorder = new RecorderOpenFace(reader.GetName(), rec_params, record_root);

                // Detect faces here and return bounding boxes
                List <Rect>  face_detections = new List <Rect>();
                List <float> confidences     = new List <float>();
                if (DetectorHOG)
                {
                    face_detector.DetectFacesHOG(face_detections, gray_frame, confidences);
                }
                else if (DetectorCNN)
                {
                    face_detector.DetectFacesMTCNN(face_detections, frame, confidences);
                }
                else if (DetectorHaar)
                {
                    face_detector.DetectFacesHaar(face_detections, gray_frame, confidences);
                }

                // For visualization
                double progress = reader.GetProgress();

                for (int i = 0; i < face_detections.Count; ++i)
                {
                    bool detection_succeeding = landmark_detector.DetectFaceLandmarksInImage(frame, face_detections[i], face_model_params, gray_frame);

                    var landmarks = landmark_detector.CalculateAllLandmarks();

                    // Predict action units
                    var au_preds = face_analyser.PredictStaticAUsAndComputeFeatures(frame, landmarks);

                    // Predic eye gaze
                    gaze_analyser.AddNextFrame(landmark_detector, detection_succeeding, reader.GetFx(), reader.GetFy(), reader.GetCx(), reader.GetCy());

                    // Only the final face will contain the details
                    VisualizeFeatures(frame, visualizer_of, landmarks, landmark_detector.GetVisibilities(), detection_succeeding, i == 0, true, reader.GetFx(), reader.GetFy(), reader.GetCx(), reader.GetCy(), progress);

                    // Record an observation
                    RecordObservation(recorder, visualizer_of.GetVisImage(), i, detection_succeeding, reader.GetFx(), reader.GetFy(), reader.GetCx(), reader.GetCy(), 0, 0);
                }

                frame      = new RawImage(reader.GetNextImage());
                gray_frame = new RawImage(reader.GetCurrentFrameGray());

                // Write out the tracked image
                if (RecordTracked)
                {
                    recorder.WriteObservationTracked();
                }

                // Do not cary state accross images
                landmark_detector.Reset();
                face_analyser.Reset();
                recorder.Close();

                lastFrameTime = CurrentTime;
                processing_fps.AddFrame();

                // TODO how to report errors from the reader here? exceptions? logging? Problem for future versions?
            }

            EndMode();
        }