利用avicap32.dll实现的实时视频传输

直接上代码吧！

在窗体上调用的类：

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

using System.Net;
using System.Net.Sockets;
using System.Threading;

namespace 实时视频传输系统
{
    public partial class MainForm : Form
    {
        public MainForm()
        {
            InitializeComponent();
        }
        /// <summary>
        /// 声明Camera类
        /// </summary>
        Camera ca = null;
        //创建一个Thread实例
        private Thread thread1;
        //创建一个UdpClient实例
        private UdpClient udpReceive;
        private UdpClient udpSend;
        private byte[] bytes;
        //private DialogResult result;
        private void btnPlay_Click(object sender, EventArgs e)
        {
            btnPlay.Enabled = false;
            btnStop.Enabled = true;

            ca = new Camera(pictureBox1.Handle, pictureBox1.Width, pictureBox1.Height);
            try
            {
                ca.StartWebCam();
            }
            catch (Exception)
            {
                MessageBox.Show("未能初始化摄像头！", "错误", MessageBoxButtons.OK, MessageBoxIcon.Error);
                btnPlay.Enabled = true;
                btnStop.Enabled = false;
                ca = null;
            }
        }

        private void btnStop_Click(object sender, EventArgs e)
        {
            try
            {
                ca.CloseWebcam();

                btnPlay.Enabled = true;
                btnStop.Enabled = false;
            }
            catch (Exception)
            {
                MessageBox.Show("摄像头关闭失败！", "错误", MessageBoxButtons.OK, MessageBoxIcon.Error);
                btnPlay.Enabled = true;
                btnStop.Enabled = false;
                ca = null;
            }
        }

        private void btnClose_Click(object sender, EventArgs e)
        {
            try
            {
                ca.CloseWebcam();

                btnPlay.Enabled = true;
                btnStop.Enabled = false;
            }
            catch (Exception)
            {
                MessageBox.Show("摄像头关闭失败！", "错误", MessageBoxButtons.OK, MessageBoxIcon.Error);
                btnPlay.Enabled = true;
                btnStop.Enabled = false;
                ca = null;
            }

            //关闭程序
            this.Close();
            Application.Exit();
        }

        private IPEndPoint ipLocalPoint;
        private EndPoint RemotePoint;
        private Socket mySocket;
        private bool RunningFlag = false;
        private void btnGetIP_Click(object sender, EventArgs e)
        {
            //string GetIP;
            //IPAddress[] AddressList = Dns.GetHostEntry(Dns.GetHostEntry()).AddressList;
            //if (AddressList.Length < 1)
            //{
            //    return "";
            //}
            //return AddressList[0].ToString();
            //this.tbGetIP.Text = Convert.ToInt32(AddressList);
        }
        //IP与端口号有效验证
        private int getValidPort(string port)
        {
            int lport;
            //测试端口号是否有效
            try
            {
                //是否为空
                if (port == "")
                {
                    throw new ArgumentException("端口号无效，不能启动UDP");
                }
                lport = System.Convert.ToInt32(port);
            }
            catch(Exception e)
            {
                Console.WriteLine("无效的端口号"+ e.ToString());
                this.tbGetPort.AppendText("无效的端口号"+ e.ToString()+"\n");
                return -;
            }
            return lport;
        }
        private IPAddress getValidIP(string ip)
        {
            IPAddress lip = null;
            //测试IP是否有效
            try
            {
                //是否为空
                if (!IPAddress.TryParse(ip, out lip))
                {
                    throw new ArgumentException("IP无效，不能启动UDP");
                }
            }
            catch(Exception e)
            {
                Console.WriteLine("无效的IP："+ e.ToString());
                this.tbGetIP.AppendText("无效的IP："+ e.ToString() +"\n");
                return null;
            }
            return lip;
        }

        private void MainForm_Load(object sender, EventArgs e)
        {
            thread1 = new Thread(new ThreadStart());
            thread1.Start();
        }

        private void btnReceive_Click(object sender, EventArgs e)
        {
            //在本机指定的端口接收
            udpReceive = new UdpClient();
            //将套接字加入组播组
            udpReceive.JoinMulticastGroup(IPAddress.Parse("224.100.0.10"), );
            //接收从远程主机发送过来的信息
            IPEndPoint iep = new IPEndPoint(IPAddress.Any, );
            while (true)
            {
                //ref表示引用类型的 IPPoint实例接收消息
                try
                {
                    bytes = udpReceive.Receive(ref iep);
                }
                catch
                {
                    DialogResult result = MessageBox.Show("发送失败！");
                }
                string str = Encoding.UTF8.GetString(bytes, , bytes.Length);
                string message = "来自" + iep.ToString() + "的消息";
                //显示消息 并以message为消息的标题
                DialogResult res = MessageBox.Show(str, message);
            }
        }

        private void btnSend_Click_1(object sender, EventArgs e)
        {
            //初始化UdpClient
            udpSend = new UdpClient();
            //实际使用时应将127.0.0.1改为服务器的远程IP
            IPAddress remoteIPAddress = IPAddress.Parse("127.0.0.1");
            IPEndPoint remoteIPEndPoint = new IPEndPoint(remoteIPAddress, );
            //将发送内容转换为字节数组
            byte[] bytes = System.Text.Encoding.UTF8.GetBytes();
            //设置重传次数
            int retry = ;
            while (true)
            {
                try
                {
                    udpSend.Send(bytes, bytes.Length, remoteIPEndPoint);
                    break;
                }
                catch
                {
                    if (retry < )
                    {
                        retry++; continue;
                    }
                    else
                    {
                        DialogResult result = MessageBox.Show("发送失败！");
                        break;
                    }
                }
            }
        }

    }
}

视频封装类：

using System;
using System.Collections.Generic;
using System.Text;

namespace Camera.avicap
{
    /// <summary>
    /// Camera 的摘要说明。
    /// </summary>
    public class Camera
    {
        private IntPtr lwndC;
        private IntPtr mControlPtr;
        private int mWidth;
        private int mHeight;

        // 构造函数
        public Camera(IntPtr handle, int width, int height)
        {
            mControlPtr = handle;
            mWidth = width;
            mHeight = height;
        }

        // 帧回调的委托
        public delegate void RecievedFrameEventHandler(byte[] data);
        public event RecievedFrameEventHandler RecievedFrame;
        private AviCapture.FrameEventHandler mFrameEventHandler;

        // 关闭摄像头
        public void CloseWebcam()
        {
            this.capDriverDisconnect(this.lwndC);
        }

        // 开启摄像头
        public void StartWebCam()
        {
            byte[] lpszName = new byte[];
            byte[] lpszVer = new byte[];

            AviCapture.capGetDriverDescriptionA(, lpszName, , lpszVer, );
            this.lwndC = AviCapture.capCreateCaptureWindowA(lpszName, AviCapture.WS_VISIBLE + AviCapture.WS_CHILD, , , mWidth, mHeight, mControlPtr, );

            if (this.capDriverConnect(this.lwndC, ))
            {
                this.capPreviewRate(this.lwndC, );
                this.capPreview(this.lwndC, true);
                AviCapture.BITMAPINFO bitmapinfo = new AviCapture.BITMAPINFO();
                bitmapinfo.bmiHeader.biSize = AviCapture.SizeOf(bitmapinfo.bmiHeader);
                bitmapinfo.bmiHeader.biWidth = this.mWidth;
                bitmapinfo.bmiHeader.biHeight = this.mHeight;
                bitmapinfo.bmiHeader.biPlanes = ;
                bitmapinfo.bmiHeader.biBitCount = ;
                this.capSetVideoFormat(this.lwndC, ref bitmapinfo, AviCapture.SizeOf(bitmapinfo));
                this.mFrameEventHandler = new AviCapture.FrameEventHandler(FrameCallBack);
                this.capSetCallbackOnFrame(this.lwndC, this.mFrameEventHandler);
                AviCapture.SetWindowPos(this.lwndC, , , , mWidth, mHeight, );
            }
        }
        // 以下为私有函数
        private bool capDriverConnect(IntPtr lwnd, short i)
        {
            return AviCapture.SendMessage(lwnd, AviCapture.WM_CAP_DRIVER_CONNECT, i, );
        }

        private bool capDriverDisconnect(IntPtr lwnd)
        {
            return AviCapture.SendMessage(lwnd, AviCapture.WM_CAP_DRIVER_DISCONNECT, , );
        }

        private bool capPreview(IntPtr lwnd, bool f)
        {
            return AviCapture.SendMessage(lwnd, AviCapture.WM_CAP_SET_PREVIEW, f, );
        }

        private bool capPreviewRate(IntPtr lwnd, short wMS)
        {
            return AviCapture.SendMessage(lwnd, AviCapture.WM_CAP_SET_PREVIEWRATE, wMS, );
        }

        private bool capSetCallbackOnFrame(IntPtr lwnd, AviCapture.FrameEventHandler lpProc)
        {
            return AviCapture.SendMessage(lwnd, AviCapture.WM_CAP_SET_CALLBACK_FRAME, , lpProc);
        }

        private bool capSetVideoFormat(IntPtr hCapWnd, ref AviCapture.BITMAPINFO BmpFormat, int CapFormatSize)
        {
            return AviCapture.SendMessage(hCapWnd, AviCapture.WM_CAP_SET_VIDEOFORMAT, CapFormatSize, ref BmpFormat);
        }

        private void FrameCallBack(IntPtr lwnd, IntPtr lpVHdr)
        {
            AviCapture.VIDEOHDR videoHeader = new AviCapture.VIDEOHDR();
            byte[] VideoData;
            videoHeader = (AviCapture.VIDEOHDR)AviCapture.GetStructure(lpVHdr, videoHeader);
            VideoData = new byte[videoHeader.dwBytesUsed];
            AviCapture.Copy(videoHeader.lpData, VideoData);
            if (this.RecievedFrame != null)
                this.RecievedFrame(VideoData);
        }
    }
}

win32的avicap32.dll封装类

using System;
using System.Collections.Generic;
using System.Runtime.InteropServices;
using System.Text;

namespace Camera.avicap
{
    /// <summary>
    /// AviCapture 的摘要说明。
    /// </summary>
    public class AviCapture
    {
        //通过调用acicap32.dll进行读取摄像头数据
        [DllImport("avicap32.dll")]
        public static extern IntPtr capCreateCaptureWindowA(byte[] lpszWindowName, int dwStyle, int x, int y, int nWidth, int nHeight, IntPtr hWndParent, int nID);
        [DllImport("avicap32.dll")]
        public static extern bool capGetDriverDescriptionA(short wDriver, byte[] lpszName, int cbName, byte[] lpszVer, int cbVer);
        [DllImport("User32.dll")]
        public static extern bool SendMessage(IntPtr hWnd, int wMsg, bool wParam, int lParam);
        [DllImport("User32.dll")]
        public static extern bool SendMessage(IntPtr hWnd, int wMsg, short wParam, int lParam);
        [DllImport("User32.dll")]
        public static extern bool SendMessage(IntPtr hWnd, int wMsg, short wParam, FrameEventHandler lParam);
        [DllImport("User32.dll")]
        public static extern bool SendMessage(IntPtr hWnd, int wMsg, int wParam, ref BITMAPINFO lParam);
        [DllImport("User32.dll")]
        public static extern int SetWindowPos(IntPtr hWnd, int hWndInsertAfter, int x, int y, int cx, int cy, int wFlags);
        [DllImport("avicap32.dll")]
        public static extern int capGetVideoFormat(IntPtr hWnd, IntPtr psVideoFormat, int wSize);

        //部分常量
        public const int WM_USER = 0x400;
        public const int WS_CHILD = 0x40000000;
        public const int WS_VISIBLE = 0x10000000;
        public const int SWP_NOMOVE = 0x2;
        public const int SWP_NOZORDER = 0x4;
        public const int WM_CAP_DRIVER_CONNECT = WM_USER + ;
        public const int WM_CAP_DRIVER_DISCONNECT = WM_USER + ;
        public const int WM_CAP_SET_CALLBACK_FRAME = WM_USER + ;
        public const int WM_CAP_SET_PREVIEW = WM_USER + ;
        public const int WM_CAP_SET_PREVIEWRATE = WM_USER + ;
        public const int WM_CAP_SET_VIDEOFORMAT = WM_USER + ;

        // 结构
        [StructLayout(LayoutKind.Sequential)]
        //VideoHdr
        public struct VIDEOHDR
        {
            [MarshalAs(UnmanagedType.I4)]
            public int lpData;
            [MarshalAs(UnmanagedType.I4)]
            public int dwBufferLength;
            [MarshalAs(UnmanagedType.I4)]
            public int dwBytesUsed;
            [MarshalAs(UnmanagedType.I4)]
            public int dwTimeCaptured;
            [MarshalAs(UnmanagedType.I4)]
            public int dwUser;
            [MarshalAs(UnmanagedType.I4)]
            public int dwFlags;
            [MarshalAs(UnmanagedType.ByValArray, SizeConst = )]
            public int[] dwReserved;
        }

        [StructLayout(LayoutKind.Sequential)]
        //BitmapInfoHeader
        public struct BITMAPINFOHEADER
        {
            [MarshalAs(UnmanagedType.I4)]
            public Int32 biSize;
            [MarshalAs(UnmanagedType.I4)]
            public Int32 biWidth;
            [MarshalAs(UnmanagedType.I4)]
            public Int32 biHeight;
            [MarshalAs(UnmanagedType.I2)]
            public short biPlanes;
            [MarshalAs(UnmanagedType.I2)]
            public short biBitCount;
            [MarshalAs(UnmanagedType.I4)]
            public Int32 biCompression;
            [MarshalAs(UnmanagedType.I4)]
            public Int32 biSizeImage;
            [MarshalAs(UnmanagedType.I4)]
            public Int32 biXPelsPerMeter;
            [MarshalAs(UnmanagedType.I4)]
            public Int32 biYPelsPerMeter;
            [MarshalAs(UnmanagedType.I4)]
            public Int32 biClrUsed;
            [MarshalAs(UnmanagedType.I4)]
            public Int32 biClrImportant;
        }

        [StructLayout(LayoutKind.Sequential)]
        //BitmapInfo
        public struct BITMAPINFO
        {
            [MarshalAs(UnmanagedType.Struct, SizeConst = )]
            public BITMAPINFOHEADER bmiHeader;
            [MarshalAs(UnmanagedType.ByValArray, SizeConst = )]
            public Int32[] bmiColors;
        }

        public delegate void FrameEventHandler(IntPtr lwnd, IntPtr lpVHdr);

        // 公共函数
        public static object GetStructure(IntPtr ptr, ValueType structure)
        {
            return Marshal.PtrToStructure(ptr, structure.GetType());
        }

        public static object GetStructure(int ptr, ValueType structure)
        {
            return GetStructure(new IntPtr(ptr), structure);
        }

        public static void Copy(IntPtr ptr, byte[] data)
        {
            Marshal.Copy(ptr, data, , data.Length);
        }

        public static void Copy(int ptr, byte[] data)
        {
            Copy(new IntPtr(ptr), data);
        }

        public static int SizeOf(object structure)
        {
            return Marshal.SizeOf(structure);
        }
    }
}

出处：https://bbs.csdn.net/topics/390039653

参考：

https://blog.csdn.net/NCTU_to_prove_safety/article/details/53584905

https://www.cnblogs.com/JUSTSOSOBLOG/p/4612801.html

https://blog.csdn.net/laolei1986/article/details/5730245

https://blog.csdn.net/waeceo/article/details/50222781

======================================================================================================

我使用AVICAP32.DLL来捕获图像,捕完并保存到文件后,当我关闭它后.那个黑块的窗体一直在那里,如果让它消失呢?

哈哈哈,我自己搞定了,由于那个窗体是使用API调出来的,它只是位置和大小与PANEL一样而已,因此要想控制它还是要使用API消息机制.利用它的句柄来操作它.方法如下:

public const int WM_CLOSE = 0x10;//关闭窗口句柄
//关闭摄像头
 if hWndC <> 0 then
  begin
   SendMessage(hWndC, WM_CAP_DRIVER_DISCONNECT, 0, 0);
   SendMessage(hWndC, WM_CLOSE, 0, 0);
   hWndC := 0;
  end;OK,完事了.

======================================================================================================

前面的代码有一个事件的处理是缺失的，就是Camera类的RecievedFrame事件；怎么把接收到的byte[] VideoData数组转成图片呢？

看看下面的文章，或许对你有所启发。

得到摄像头一帧数据的字节数组之后转成图片的处理