form1.cs

This approach, we feel, came very close to obtaining an image from the camera OV7620. Before we trie

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.Threading;
using System.IO;

namespace RS232Capture
{
    public partial class Form1 : Form
    {
        Mutex m_ImageLock = new Mutex();
        Mutex m_FrameLock = new Mutex();

        Queue<byte[]> m_Frames = new Queue<byte[]>();

        public Form1()
        {
            InitializeComponent();
            m_ControlThread = new Thread(Listen);
            m_ControlThread.Start();
            m_DrawThread = new Thread(Draw);
            m_DrawThread.Start();

            m_Image = new Bitmap(pictureBox1.Width, pictureBox1.Height);
            pictureBox1.Paint += new PaintEventHandler(pictureBox1_Paint);
        }

        void pictureBox1_Paint(object sender, PaintEventArgs e)
        {
            m_ImageLock.WaitOne();
            e.Graphics.DrawImage(m_Image, 0.0f, 0.0f);
            m_ImageLock.ReleaseMutex();
        }

        public void Listen()
        {
            while (_continue)
            {
                if (ThePort.IsOpen)
                {
                  
                    try
                    {  
                        byte[] pixels = new byte[ThePort.BytesToRead];


                        ThePort.Read(pixels, 0, ThePort.BytesToRead);
                        /*if (!File.Exists("data.out"))
                        {
                            FileStream f = File.Open("data.out", FileMode.OpenOrCreate);
                            f.Write(pixels, 0, pixels.Length);
                            f.Close();
                        }*/
                        m_FrameLock.WaitOne();
                        m_Frames.Enqueue(pixels);
                        m_FrameLock.ReleaseMutex();
                        Thread.Sleep(0);
                    }
                    catch (Exception e)
                    {
                        //do nothing
                    }
                }
            }
        }

        public void Draw()
        {
            while (_continue)
            {
                if (m_Frames.Count > 0)
                {
                    m_FrameLock.WaitOne();
                    byte[] pixels = m_Frames.Dequeue();
                    m_FrameLock.ReleaseMutex();
                    DrawPixels(pixels);
                    Thread.Sleep(0);
                }
            }
        }

        private delegate void PixelDrawer(byte[] pixels);

        private void DrawPixels(byte[] pixels)
        {
            for (int i = 0; i < pixels.Length; i++)
            {
                m_Image.SetPixel(m_CurrentPixel % m_ImageWidth, m_CurrentPixel / m_ImageWidth, Color.FromArgb(pixels[i], pixels[i], pixels[i]));
                m_CurrentPixel = (m_CurrentPixel == m_ImageWidth * m_ImageHeight - 1) ? 0 : m_CurrentPixel + 1;

                if (m_CurrentPixel == 0)
                {
                    pictureBox1.Invalidate();
                    m_CurrentFrame++;
                    Thread.Sleep(100);
                    Graphics g = Graphics.FromImage(m_Image);
                    g.Clear(Color.White);
                    textBox2.Text = m_CurrentFrame.ToString();
                }
                //textBox1.Text += "." + pixels[i].ToString();
            }
        }

        private int m_CurrentPixel = 0;
        private Bitmap m_Image;
        private int m_ImageWidth = 320;
        private int m_ImageHeight = 240;
        private Thread m_ControlThread;
        private Thread m_DrawThread;
        private bool _continue = true;
        private int m_CurrentFrame = 0;

        private void button1_Click(object sender, EventArgs e)
        {
            try
            {
                ThePort.Open();
                byte[] handshake = new Byte[1];
                handshake[0] = 3;
                ThePort.Write(handshake, 0, 1);
            }
            catch (Exception ex)
            {
                textBox1.Text += "\n" + ex.Message;
            }
        }

        private void button2_Click(object sender, EventArgs e)
        {
            try
            {
                ThePort.Close();
            }
            catch (Exception ex)
            {
                textBox1.Text += "\n" + ex.Message;
            }
        }

        private void Form1_FormClosing(object sender, FormClosingEventArgs e)
        {
            try
            {
                _continue = false;
                ThePort.Close();
                ThePort.Dispose();
            }
            catch (Exception ex)
            {
                textBox1.Text += "\n" + ex.Message;
            }
        }
   }

}