Image Tracking and Computer Vision Using Fourier Image Correlation

///////////////////////////////////////////////////////////////////////////////
//
//  ImageMarkerList.cs
//
//  By Philip R. Braica (HoshiKata@aol.com, VeryMadSci@gmail.com)
//
//  Distributed under the The Code Project Open License (CPOL)
//  http://www.codeproject.com/info/cpol10.aspx
///////////////////////////////////////////////////////////////////////////////

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Drawing;

namespace OpenCVDemo
{
    public class ImageMarkerList
    {
        /// <summary>
        /// Marker list.
        /// </summary>
        protected List<marker> m_list = new List<marker>();

        /// <summary>
        /// Clear.
        /// </summary>
        public void Clear() { m_list.Clear(); }

        /// <summary>
        /// Add text and point.
        /// </summary>
        /// <param name="text"></param>
        /// <param name="p"></param>
        public void Add(string text, System.Drawing.Point p)
        {
            m_list.Add(new marker(text, p));
        }

        /// <summary>
        /// Add text and point.
        /// </summary>
        /// <param name="text"></param>
        /// <param name="p"></param>
        public void Add(string text, System.Drawing.PointF p)
        {
            Add(text, new System.Drawing.Point((int)p.X, (int)p.Y));
        }

        /// <summary>
        /// Add text and rectangle.
        /// </summary>
        /// <param name="text"></param>
        /// <param name="r"></param>
        public void Add(string text, System.Drawing.Rectangle r)
        {
            m_list.Add(new marker(text, r));
        }

        /// <summary>
        /// Add text and rectangle.
        /// </summary>
        /// <param name="text"></param>
        /// <param name="r"></param>
        public void Add(string text, System.Drawing.RectangleF r)
        {
            Add(text, new System.Drawing.Rectangle((int)r.Left, (int)r.Top, (int)r.Width, (int)r.Height));
        }

        /// <summary>
        /// Render.
        /// </summary>
        /// <param name="b"></param>
        /// <param name="stemLength"></param>
        /// <param name="opacity"></param>
        public void Render(System.Drawing.Bitmap b, Font f)
        {
            Render(b, f, 16, 0.7f);
        }

        /// <summary>
        /// Render.
        /// </summary>
        /// <param name="b"></param>
        /// <param name="stemLength"></param>
        /// <param name="opacity"></param>
        public void Render(System.Drawing.Bitmap b, Font f, int stemLength, float opacity)
        {
            int w = b.Width;
            int h = b.Height;
            System.Drawing.Color [] clrs = {
                Color.Red, Color.Blue, Color.Green, Color.Orange, Color.Purple, Color.Brown,
                Color.Cyan, Color.Magenta, Color.Aqua, Color.GreenYellow, 
                Color.Gray, Color.Crimson, Color.BlueViolet, Color.Olive,
                Color.OrangeRed, Color.Plum, Color.PeachPuff, Color.PaleTurquoise, Color.Orchid,
                Color.SandyBrown, Color.RoyalBlue, Color.Lime, Color.Violet, Color.DarkCyan};
            int op = (int)(255 * opacity);
            op = op < 0 ? op : op > 255 ? 255 : op;
            using (System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(b))
            {
                for (int i = 0; i < m_list.Count; i++)
                {
                    Color c = Color.FromArgb(op, clrs[i%clrs.Length]);
                    float angle = 11.61f * ((4095 * i) % 31);
                    m_list[i].Draw(g, f, c, w, h, stemLength, angle);
                }
            }
        }

        /// <summary>
        /// Marker inernal class.
        /// </summary>
        protected class marker
        {
            /// <summary>
            /// Draw.
            /// </summary>
            /// <param name="g"></param>
            /// <param name="c"></param>
            /// <param name="w"></param>
            /// <param name="h"></param>
            /// <param name="stemLength"></param>
            /// <param name="angle"></param>
            public void Draw(System.Drawing.Graphics g, Font f, Color c, int w, int h, int stemLength, float angle)
            {
                string text = Text;

                angle = angle * (float)System.Math.PI / 180f;
    
                Point src = new Point();
                Point dst = new Point();
                int radius = 4;
                if (!IsRect)
                {
                    src = new Point(
                        (int)(Location.X + ((stemLength) * System.Math.Cos(angle))),
                        (int)(Location.Y + ((stemLength) * System.Math.Sin(angle))));

                    dst = new Point(
                        (int)(Location.X + ((radius + stemLength) * System.Math.Cos(angle))),
                        (int)(Location.Y + ((radius + stemLength) * System.Math.Sin(angle))));
                }
                else
                {
                    if (angle < System.Math.PI/2)
                    {
                        // Top right corner.
                        src = new Point(Rectangle.Right, Rectangle.Top);
                    }
                    if ((angle >= System.Math.PI/2) && (angle < System.Math.PI))
                    {
                        // Top left corner.
                        src = new Point(Rectangle.Left, Rectangle.Top);
                    }
                    if ((angle >= System.Math.PI) && (angle < 3*System.Math.PI/2))
                    {
                        // Bottom left corner.
                        src = new Point(Rectangle.Left, Rectangle.Bottom);
                    }
                    if (angle >= 3*System.Math.PI/2)
                    {
                        // Bottom right corner.
                        src = new Point(Rectangle.Right, Rectangle.Bottom);
                    }
                    dst = new Point(
                        (int)(src.X + ((stemLength) * System.Math.Cos(angle))),
                        (int)(src.Y + ((stemLength) * System.Math.Sin(angle))));
                }

                if ((text.Length > 0) && (f != null))
                {
                    SizeF sf = g.MeasureString(text, f);
                    using (Pen p = new Pen(c, 1))
                    {
                        g.DrawLine(p, src, dst);
                    }
                    using (SolidBrush sb = new SolidBrush(c))
                    {
                        if (src.X > dst.X)
                        {
                            // left.
                            dst.X -= (int)(sf.Width + 0.5f);
                        }
                        if (src.Y > dst.Y)
                        {
                            // upper left.
                            dst.Y -= (int)(sf.Height + 0.5f);
                        }
                        using (SolidBrush sbBack = new SolidBrush(Color.FromArgb(128, Color.Gray)))
                        {
                            g.FillRectangle(sbBack, dst.X, dst.Y, (int)sf.Width + 1, (int)sf.Height + 1);
                        }
                        g.DrawString(Text, f, sb, dst);
                    }
                }
            }

            /// <summary>
            /// Point constructor.
            /// </summary>
            /// <param name="text"></param>
            /// <param name="p"></param>
            public marker(string text, System.Drawing.Point p)
            {
                IsRect = false;
                Location = p;
                Text = text;
            }

            /// <summary>
            /// Rectangle constructor.
            /// </summary>
            /// <param name="text"></param>
            /// <param name="r"></param>
            public marker(string text, System.Drawing.Rectangle r)
            {
                IsRect = true;
                Rectangle = r;
                Text = text;
            }

            /// <summary>
            /// Is rectangle.
            /// </summary>
            public bool IsRect { get; set; }

            /// <summary>
            /// Location.
            /// </summary>
            public System.Drawing.Point Location { get; set; }

            /// <summary>
            /// Rectangle.
            /// </summary>
            public System.Drawing.Rectangle Rectangle { get; set; }

            /// <summary>
            /// Text.
            /// </summary>
            public string Text { get; set; }
        }
    }

    

}