Emgu.CV.CvInvoke.CV_MAKETYPE C# (CSharp) Method

        public static int CV_MAKETYPE(int depth, int cn)
        {
            return ((depth) + (((cn) - 1) << 3));
        }

        /// <summary>
        /// Fit an ellipse to the points collection
        /// </summary>
        /// <param name="points">The points to be fitted</param>
        /// <returns>An ellipse</returns>
        public static Ellipse EllipseLeastSquareFitting(PointF[] points)
        {
            IntPtr   seq    = Marshal.AllocHGlobal(StructSize.MCvSeq);
            IntPtr   block  = Marshal.AllocHGlobal(StructSize.MCvSeqBlock);
            GCHandle handle = GCHandle.Alloc(points, GCHandleType.Pinned);

            CvInvoke.cvMakeSeqHeaderForArray(
                CvInvoke.CV_MAKETYPE((int)CvEnum.MAT_DEPTH.CV_32F, 2),
                StructSize.MCvSeq,
                StructSize.PointF,
                handle.AddrOfPinnedObject(),
                points.Length,
                seq,
                block);
            Ellipse e = new Ellipse(CvInvoke.cvFitEllipse2(seq));

            //The angle returned by cvFitEllipse2 has the wrong sign.
            //Returned angle is clock wise rotation, what we need for the definition of MCvBox is the counter clockwise rotation.
            //For this, we needs to change the sign of the angle
            MCvBox2D b = e.MCvBox2D;

            b.angle = -b.angle;
            if (b.angle < 0)
            {
                b.angle += 360;
            }
            e.MCvBox2D = b;

            handle.Free();
            Marshal.FreeHGlobal(seq);
            Marshal.FreeHGlobal(block);
            return(e);
        }