public void TestArray2dRgbPixel()
        {
            using (var window = new ImageWindow())
                using (var src = new Array2dRgbPixel())
                {
                    const string imagePath = "images\\lenna.bmp";
                    var          bmp       = new System.Drawing.Bitmap(imagePath);
                    src.SetBitmap(bmp);
                    window.SetImage(src);
                    OpenCvSharp.Cv2.WaitKey(Cv2WaitKeyDelay);

                    using (var image = new Array2dRgbPixel(src))
                    {
                        image.PyramidUp();
                        window.SetImage(image);
                        OpenCvSharp.Cv2.WaitKey(Cv2WaitKeyDelay);

                        image.ResizeImage(image.Width / 2, image.Height / 2);
                        window.SetImage(image);
                        OpenCvSharp.Cv2.WaitKey(Cv2WaitKeyDelay);
                    }
                    using (var image = new Array2dRgbPixel(640, 480))
                    {
                        // Quadratic does not work.
                        Array2dRgbPixel.ResizeImageWithResizeImageInterporateKind(src, image, ResizeImageInterporateKind.Bilinear);
                        window.SetImage(image);
                        OpenCvSharp.Cv2.WaitKey(Cv2WaitKeyDelay);
                    }
                }
        }
        public void TestFaceLandmarkDetection()
        {
            const string imagePath = "images\\lenna.bmp";

            using (var window = new ImageWindow())
                using (var image = new Array2dRgbPixel())
                    using (var detector = new FaceLandmarkDetection("D:/Data/Dlib/shape_predictor_68_face_landmarks.dat"))
                    {
                        var bmp = new System.Drawing.Bitmap(imagePath);
                        image.SetBitmap(bmp);
                        image.PyramidUp();
                        window.SetImage(image);
                        OpenCvSharp.Cv2.WaitKey(Cv2WaitKeyDelay);
                        var landmarks = detector.DetectFaceLandmarks(image, -0.5);
                        foreach (var landmark in landmarks)
                        {
                            Console.WriteLine(landmark.ToString());
                        }
                    }
        }
        public void RawApiFaceLandmarkDetectionUsingMemoryInput()
        {
            const string imagePath  = "images\\lenna.bmp";
            var          imageBytes = File.ReadAllBytes(imagePath);

            IntPtr detector = IntPtr.Zero;
            IntPtr dets     = IntPtr.Zero;

            try
            {
                using (var window = new ImageWindow())
                    using (var image = new Array2dRgbPixel())
                    {
                        Console.WriteLine($"Size: ({image.Width},{image.Height})");
                        Trace.Assert(image.Width == 0 && image.Height == 0);
                        window.SetImage(image);
                        OpenCvSharp.Cv2.WaitKey(Cv2WaitKeyDelay);

                        NativeMethods.dlib_load_bmp_array2d_rgbpixel(image.DlibArray2dRgbPixel, imageBytes, new IntPtr(imageBytes.Length));
                        Console.WriteLine($"Size: ({image.Width},{image.Height})");
                        Trace.Assert(image.Width == 512 && image.Height == 480);
                        window.SetImage(image);
                        OpenCvSharp.Cv2.WaitKey(Cv2WaitKeyDelay);

                        image.SetBitmap(new System.Drawing.Bitmap(imagePath));
                        Console.WriteLine($"Size: ({image.Width},{image.Height})");
                        Trace.Assert(image.Width == 512 && image.Height == 480);
                        window.SetImage(image);
                        OpenCvSharp.Cv2.WaitKey(Cv2WaitKeyDelay);

                        image.PyramidUp();
                        Console.WriteLine($"Size: ({image.Width},{image.Height})");
                        window.SetImage(image);
                        OpenCvSharp.Cv2.WaitKey(Cv2WaitKeyDelay);

                        detector = NativeMethods.dlib_get_face_landmark_detection("D:/Data/Dlib/shape_predictor_68_face_landmarks.dat");
                        dets     = NativeMethods.vector_FaceLandmarkInternal_new1();
                        NativeMethods.dlib_face_landmark_detection_operator(detector, image.DlibArray2dRgbPixel, -0.5, dets);
                        Trace.Assert(dets != null && dets != IntPtr.Zero);
                        long count = NativeMethods.vector_FaceLandmarkInternal_getSize(dets).ToInt64();
                        // If it does not return ret here, exception occurs.
                        if (count > 0)
                        {
                            unsafe
                            {
                                FaceLandmarkInternal *faceLandmarkInternals = (FaceLandmarkInternal *)NativeMethods.vector_FaceLandmarkInternal_getPointer(dets).ToPointer();
                                for (int i = 0; i < count; i++)
                                {
                                    Console.WriteLine(new FaceLandmark(faceLandmarkInternals[i]));
                                }
                            }
                        }
                    }
            }
            finally
            {
                if (detector != IntPtr.Zero)
                {
                    NativeMethods.dlib_face_landmark_detection_delete(detector);
                }
                if (dets != IntPtr.Zero)
                {
                    NativeMethods.vector_FaceLandmarkInternal_delete(dets);
                }
            }
        }