c# 获取 摄像头 实现录像

c# 获取 摄像头 实现录像

利用普通的简易摄像头，通过C#语言即可开发成简易视频程序。本实例利用市场上购买的普通摄像头，利用VFW技术，实现单路视频监控系统。运行程序，窗体中将显示舰体摄像头采集的视频信息。如图13.9所示。
技术要点
本实例主要使用了VFW（Video for Windows）技术。VFW 是Microsoft公司为开发Windows平台下的视频应用程序提供的软件工具包，提供了一系列应用程序编程接口（API），用户可以通过这些接口很方便地实现视频捕获、视频编辑及视频播放等通用功能，还可利用回调函数开发比较复杂的视频应用程序。该技术的特点是播放视频时不需要专用的硬件设备，而且应用灵活，可以满足视频应用程序开发的需要。Windows操作系统自身就携带了VFW技术，系统安装时，会自动安装VFW的相关组件。
VFW技术主要由六个功能模块组成，下面进行简单说明。
AVICAP32.DLL：包含执行视频捕获的函数，给AVI文件的I/O处理和视频，音频设备驱动程序提供一个高级接口。
MSVIDEO.DLL：包含一套特殊的DrawDib函数，用来处理程序上的视频操作。
MCIAVI.DRV：包括对VFW的MCI命令解释器的驱动程序。
AVIFILE.DLL：包含由标准多媒体I/O（mmio）函数提供的更高级的命令，用来访问.AVI文件。
ICM：压缩管理器，用于管理的视频压缩/解压缩的编译码器。
ACM：音频压缩管理器，提供与ICM相似的服务，适用于波形音频。
AVICAP32.DLL中的函数和USER32.DLL中的函数，函数语法及结构如下。
（1）capCreateCaptureWindow函数
该函数用于创建一个视频捕捉窗口。语法如下：
[DllImport("avicap32.dll")]
public static extern IntPtr capCreateCaptureWindowA(byte[] lpszWindowName, int dwStyle, int x, int y, int nWidth, int nHeight, IntPtr hWndParent, int nID);
参数说明如下。
lpszWindowName：标识窗口的名称。
dwStyle：标识窗口风格。
x、y：标识窗口的左上角坐标。
nWidth、nHeight：标识窗口的宽度和高度。
hWnd：标识父窗口句柄。
nID：标识窗口ID。
返回值：视频捕捉窗口句柄。
（2）SendMessage函数
用于向Windows系统发送消息机制。
[DllImport("User32.dll")]
private static extern bool SendMessage(IntPtr hWnd, int wMsg, int wParam, int lParam);
参数说明如下。
hWnd：窗口句柄。
wMsg：将要发送的消息。
wParam、lParam：消息的参数，每个消息都有两个参数，参数设置由发送的消息而定。

Form1窗体中通过调用视频类中的方法来实现相应的功能。

在【开始录像】按钮的Click事件中添加如下代码：

private void buttonStart_Click(object sender, EventArgs e)
{
buttonStart.Enabled = false;
buttonStop.Enabled = true;
//btnPz.Enabled = true;
video = new cVideo(picCapture.Handle, picCapture.Width, picCapture.Height);
video.StartWebCam();
}

在【停止录像】按钮的Click事件中添加如下代码：

private void buttonStop_Click(object sender, EventArgs e)
{
buttonStart.Enabled = true;
buttonStop.Enabled = false;
buttonPz.Enabled = false;
video.CloseWebcam();
}

在【拍照】按钮的Click事件下添加如下代码：

private void buttonPz_Click(object sender, EventArgs e)
{
video.GrabImage(picCapture.Handle, "d:\\a.bmp");
}

完整代码如下：

1、Program.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Windows.Forms;

namespace Video1
{
static class Program
{
/// <summary>
/// 应用程序的主入口点。
/// </summary>
[STAThread]
static void Main()
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Application.Run(new Form1());
}
}
}

2、Form1.cs

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

namespace Video1
{
public partial class Form1 : Form
{
cVideo video;
public Form1()
{
InitializeComponent();
}

private void buttonStart_Click(object sender, EventArgs e)
{
buttonStart.Enabled = false;
buttonStop.Enabled = true;
//btnPz.Enabled = true;
video = new cVideo(picCapture.Handle, picCapture.Width, picCapture.Height);
video.StartWebCam();
}

private void buttonStop_Click(object sender, EventArgs e)
{
buttonStart.Enabled = true;
buttonStop.Enabled = false;
buttonPz.Enabled = false;
video.CloseWebcam();
}

private void buttonPz_Click(object sender, EventArgs e)
{
video.GrabImage(picCapture.Handle, "d:\\a.bmp");
}
}
}

3、Form1.Designer.cs

namespace Video1
{
partial class Form1
{
/// <summary>
/// 必需的设计器变量。
/// </summary>
private System.ComponentModel.IContainer components = null;

/// <summary>
/// 清理所有正在使用的资源。
/// </summary>
/// <param>如果应释放托管资源，为 true；否则为 false。</param>
protected override void Dispose(bool disposing)
{
if (disposing && (components != null))
{
components.Dispose();
}
base.Dispose(disposing);
}

#region Windows 窗体设计器生成的代码

/// <summary>
/// 设计器支持所需的方法 - 不要
/// 使用代码编辑器修改此方法的内容。
/// </summary>
private void InitializeComponent()
{
System.ComponentModel.ComponentResourceManager resources = new System.ComponentModel.ComponentResourceManager(typeof(Form1));
this.buttonStart = new System.Windows.Forms.Button();
this.buttonStop = new System.Windows.Forms.Button();
this.buttonPz = new System.Windows.Forms.Button();
this.panelTop = new System.Windows.Forms.Panel();
this.picCapture = new System.Windows.Forms.PictureBox();
this.panelBottom = new System.Windows.Forms.Panel();
this.panelTop.SuspendLayout();
((System.ComponentModel.ISupportInitialize)(this.picCapture)).BeginInit();
this.panelBottom.SuspendLayout();
this.SuspendLayout();
//
// buttonStart
//
this.buttonStart.Location = new System.Drawing.Point(39, 3);
this.buttonStart.Name = "buttonStart";
this.buttonStart.Size = new System.Drawing.Size(88, 36);
this.buttonStart.TabIndex = 1;
this.buttonStart.Text = "开始录像";
this.buttonStart.UseVisualStyleBackColor = true;
this.buttonStart.Click += new System.EventHandler(this.buttonStart_Click);
//
// buttonStop
//
this.buttonStop.Location = new System.Drawing.Point(181, 3);
this.buttonStop.Name = "buttonStop";
this.buttonStop.Size = new System.Drawing.Size(80, 36);
this.buttonStop.TabIndex = 2;
this.buttonStop.Text = "停止录像";
this.buttonStop.UseVisualStyleBackColor = true;
this.buttonStop.Click += new System.EventHandler(this.buttonStop_Click);
//
// buttonPz
//
this.buttonPz.Location = new System.Drawing.Point(313, 3);
this.buttonPz.Name = "buttonPz";
this.buttonPz.Size = new System.Drawing.Size(77, 36);
this.buttonPz.TabIndex = 3;
this.buttonPz.Text = "拍 照";
this.buttonPz.UseVisualStyleBackColor = true;
this.buttonPz.Click += new System.EventHandler(this.buttonPz_Click);
//
// panelTop
//
this.panelTop.AutoSize = true;
this.panelTop.Controls.Add(this.picCapture);
this.panelTop.Dock = System.Windows.Forms.DockStyle.Fill;
this.panelTop.Location = new System.Drawing.Point(0, 0);
this.panelTop.Name = "panelTop";
this.panelTop.Size = new System.Drawing.Size(468, 372);
this.panelTop.TabIndex = 4;
//
// picCapture
//
this.picCapture.Dock = System.Windows.Forms.DockStyle.Fill;
this.picCapture.InitialImage = ((System.Drawing.Image)(resources.GetObject("picCapture.InitialImage")));
this.picCapture.Location = new System.Drawing.Point(0, 0);
this.picCapture.Name = "picCapture";
this.picCapture.Size = new System.Drawing.Size(468, 372);
this.picCapture.TabIndex = 0;
this.picCapture.TabStop = false;
//
// panelBottom
//
this.panelBottom.Controls.Add(this.buttonStart);
this.panelBottom.Controls.Add(this.buttonStop);
this.panelBottom.Controls.Add(this.buttonPz);
this.panelBottom.Dock = System.Windows.Forms.DockStyle.Bottom;
this.panelBottom.Location = new System.Drawing.Point(0, 327);
this.panelBottom.Name = "panelBottom";
this.panelBottom.Size = new System.Drawing.Size(468, 45);
this.panelBottom.TabIndex = 5;
//
// Form1
//
this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 12F);
this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
this.ClientSize = new System.Drawing.Size(468, 372);
this.Controls.Add(this.panelBottom);
this.Controls.Add(this.panelTop);
this.Name = "Form1";
this.Text = "Form1";
this.panelTop.ResumeLayout(false);
((System.ComponentModel.ISupportInitialize)(this.picCapture)).EndInit();
this.panelBottom.ResumeLayout(false);
this.ResumeLayout(false);
this.PerformLayout();

}

#endregion

private System.Windows.Forms.PictureBox picCapture;
private System.Windows.Forms.Button buttonStart;
private System.Windows.Forms.Button buttonStop;
private System.Windows.Forms.Button buttonPz;
private System.Windows.Forms.Panel panelTop;
private System.Windows.Forms.Panel panelBottom;
}
}

4、ClassVideoAPI.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Drawing;
using System.Runtime.InteropServices;
using System.Threading;
using System.Windows.Forms;
using System.IO;

namespace Video1
{
public class VideoAPI //视频API类
{
// 视频ＡＰＩ调用
[DllImport("avicap32.dll")]//包含了执行视频捕获的函数，它给AVI文件I/O和视频、音频设备驱动程序提供一个高级接口
public static extern IntPtr capCreateCaptureWindow(string lpszWindowName, int dwStyle, int x, int y, int nWidth, int nHeight, IntPtr hwndParent, int nID);
[DllImport("AVICAP32.dll", CharSet = CharSet.Unicode)]
public static extern bool capGetDriverDescription(int wDriverIndex, StringBuilder lpszName, int cbName, StringBuilder lpszVer, int cbVer);
[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, int 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 bool SendMessage(IntPtr hWnd, int wMsg, int wParam, ref CAPDRIVERCAPS lParam);
[DllImport("User32.dll")]
public static extern bool SendMessage(IntPtr hWnd, int wMsg, int wParam, ref CAPTUREPARMS lParam);
[DllImport("User32.dll")]
public static extern bool SendMessage(IntPtr hWnd, int wMsg, int wParam, ref CAPSTATUS 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);

// 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 + 10;
// public const int WM_CAP_DRIVER_DISCONNECT = WM_USER + 11;
public const int WM_CAP_SET_CALLBACK_FRAME = WM_USER + 5;
// public const int WM_CAP_SET_PREVIEW = WM_USER + 50;
// public const int WM_CAP_SET_PREVIEWRATE = WM_USER + 52;
// public const int WM_CAP_SET_VIDEOFORMAT = WM_USER + 45;
// public const int WM_CAP_START = WM_USER;
public const int WM_CAP_SAVEDIB = WM_CAP_START + 25;

public const string avicap32 = "avicap32.dll";
public const int WM_USER = 1024;
/// <summary>
///WM_CAP_START=WM_USER=1024
/// </summary>
public const int WM_CAP_START = WM_USER;

// start of unicode messages
/// <summary>
/// 开始 WM_USER + 100=1124
/// </summary>
public const int WM_CAP_UNICODE_START = WM_USER + 100; //开始 1124
/// <summary>
/// /获得 CAPSTR EAMPTR
/// WM_CAP_START + 1=1025
/// </summary>
public const int WM_CAP_GET_CAPSTREAMPTR = (WM_CAP_START + 1); //获得 CAPSTR EAMPTR
/// <summary>
/// 设置收回错误 WM_CAP_START + 2=1026
/// </summary>
public const int WM_CAP_SET_CALLBACK_ERROR = (WM_CAP_START + 2); //设置收回错误
/// <summary>
/// 设置收回状态 WM_CAP_START + 3=1027
/// </summary>
public const int WM_CAP_SET_CALLBACK_STATUS = (WM_CAP_START + 3); //设置收回状态
/// <summary>
/// 设置收回出产 WM_CAP_START + 4=1028
/// </summary>
public const int WM_CAP_SET_CALLBACK_YIELD = (WM_CAP_START + 4); //设置收回出产
/// <summary>
/// 设置收回结构 WM_CAP_START + 5=1029
/// </summary>
public const int WM_CAP_SET_CALLBACK_FRame = (WM_CAP_START + 5); //设置收回结构
/// <summary>
/// 设置收回视频流 WM_CAP_START + 6=1030
/// </summary>
public const int WM_CAP_SET_CALLBACK_VIDEOSTREAM = (WM_CAP_START + 6); //设置收回视频流
/// <summary>
/// 设置收回视频波流 WM_CAP_START +7=1031
/// </summary>
public const int WM_CAP_SET_CALLBACK_WAVESTREAM = (WM_CAP_START + 7); //设置收回视频波流
/// <summary>
/// 获得使用者数据 WM_CAP_START + 8=1032
/// </summary>
public const int WM_CAP_GET_USER_DATA = (WM_CAP_START + 8); //获得使用者数据
/// <summary>
/// 设置使用者数据 WM_CAP_START + 9=1033
/// </summary>
public const int WM_CAP_SET_USER_DATA = (WM_CAP_START + 9); //设置使用者数据
/// <summary>
/// 驱动程序连接 WM_CAP_START + 10=1034
/// </summary>
public const int WM_CAP_DRIVER_CONNECT = (WM_CAP_START + 10); //驱动程序连接
/// <summary>
/// 断开启动程序连接 WM_CAP_START + 11=1035
/// </summary>
public const int WM_CAP_DRIVER_DISCONNECT = (WM_CAP_START + 11); //断开启动程序连接
/// <summary>
/// 获得驱动程序名字 WM_CAP_START + 12=1036
/// </summary>
public const int WM_CAP_DRIVER_GET_NAME = (WM_CAP_START + 12); //获得驱动程序名字
/// <summary>
/// 获得驱动程序版本 WM_CAP_START + 13=1037
/// </summary>
public const int WM_CAP_DRIVER_GET_VERSION = (WM_CAP_START + 13); //获得驱动程序版本
/// <summary>
/// 获得驱动程序帽子 WM_CAP_START + 14=1038
/// </summary>
public const int WM_CAP_DRIVER_GET_CAPS = (WM_CAP_START + 14); //获得驱动程序帽子
/// <summary>
/// 设置捕获文件 WM_CAP_START + 20=1044
/// </summary>
public const int WM_CAP_FILE_SET_CAPTURE_FILE = (WM_CAP_START + 20); //设置捕获文件
/// <summary>
/// 获得捕获文件 WM_CAP_START + 21=1045
/// </summary>
public const int WM_CAP_FILE_GET_CAPTURE_FILE = (WM_CAP_START + 21); //获得捕获文件
/// <summary>
/// 另存文件为 WM_CAP_START + 23=1047
/// </summary>
public const int WM_CAP_FILE_SAVEAS = (WM_CAP_START + 23); //另存文件为
/// <summary>
/// 保存文件 WM_CAP_START + 25=1049
/// </summary>
public const int WM_CAP_FILE_SAVEDIB = (WM_CAP_START + 25); //保存文件

// out of order to save on ifdefs
/// <summary>
/// 分派文件 WM_CAP_START + 22=1044
/// </summary>
public const int WM_CAP_FILE_ALLOCATE = (WM_CAP_START + 22); //分派文件
/// <summary>
/// 设置开始文件 WM_CAP_START + 24=1046
/// </summary>
public const int WM_CAP_FILE_SET_INFOCHUNK = (WM_CAP_START + 24); //设置开始文件
/// <summary>
/// 编辑复制 WM_CAP_START + 30=1054
/// </summary>
public const int WM_CAP_EDIT_COPY = (WM_CAP_START + 30); //编辑复制
/// <summary>
/// 设置音频格式 WM_CAP_START + 35=1059
/// </summary>
public const int WM_CAP_SET_AUDIOFORMAT = (WM_CAP_START + 35); //设置音频格式
/// <summary>
/// 捕获音频格式 WM_CAP_START + 36=1060
/// </summary>
public const int WM_CAP_GET_AUDIOFORMAT = (WM_CAP_START + 36); //捕获音频格式
/// <summary>
/// 打开视频格式设置对话框 WM_CAP_START + 41=1065
/// </summary>
public const int WM_CAP_DLG_VIDEOFORMAT = (WM_CAP_START + 41); //1065 打开视频格式设置对话框
/// <summary>
/// 打开属性设置对话框，设置对比度、亮度等 WM_CAP_START + 42=1066
/// </summary>
public const int WM_CAP_DLG_VIDEOSOURCE = (WM_CAP_START + 42); //1066 打开属性设置对话框，设置对比度、亮度等。
/// <summary>
/// 打开视频显示 WM_CAP_START + 43=1067
/// </summary>
public const int WM_CAP_DLG_VIDEODISPLAY = (WM_CAP_START + 43); //1067 打开视频显示
/// <summary>
/// 获得视频格式 WM_CAP_START + 44=1068
/// </summary>
public const int WM_CAP_GET_VIDEOFORMAT = (WM_CAP_START + 44); //1068 获得视频格式
/// <summary>
/// 设置视频格式 WM_CAP_START + 45=1069
/// </summary>
public const int WM_CAP_SET_VIDEOFORMAT = (WM_CAP_START + 45); //1069 设置视频格式
/// <summary>
/// 打开压缩设置对话框 WM_CAP_START + 46=1070
/// </summary>
public const int WM_CAP_DLG_VIDEOCOMPRESSION = (WM_CAP_START + 46); //1070 打开压缩设置对话框
/// <summary>
/// 设置预览 WM_CAP_START + 50=1074
/// </summary>
public const int WM_CAP_SET_PREVIEW = (WM_CAP_START + 50); //设置预览
/// <summary>
/// 设置覆盖 WM_CAP_START + 51=1075
/// </summary>
public const int WM_CAP_SET_OVERLAY = (WM_CAP_START + 51); //设置覆盖
/// <summary>
/// 设置预览比例 WM_CAP_START + 52=1076
/// </summary>
public const int WM_CAP_SET_PREVIEWRATE = (WM_CAP_START + 52); //设置预览比例
/// <summary>
/// 设置刻度 WM_CAP_START + 53=1077
/// </summary>
public const int WM_CAP_SET_SCALE = (WM_CAP_START + 53); //设置刻度
/// <summary>
/// 获得状态 WM_CAP_START + 54=1078
/// </summary>
public const int WM_CAP_GET_STATUS = (WM_CAP_START + 54); //获得状态
/// <summary>
/// 设置卷 WM_CAP_START + 55=1079
/// </summary>
public const int WM_CAP_SET_SCROLL = (WM_CAP_START + 55); //设置卷
/// <summary>
/// 逮捕结构 WM_CAP_START + 60=1084
/// </summary>
public const int WM_CAP_GRAB_FRame = (WM_CAP_START + 60); //逮捕结构
/// <summary>
/// 停止逮捕结构 WM_CAP_START + 61=1085
/// </summary>
public const int WM_CAP_GRAB_FRame_NOSTOP = (WM_CAP_START + 61); //停止逮捕结构
/// <summary>
/// 次序 WM_CAP_START + 62=1086
/// </summary>
public const int WM_CAP_SEQUENCE = (WM_CAP_START + 62); //次序
/// <summary>
/// 没有文件 WM_CAP_START + 63=1087
/// </summary>
public const int WM_CAP_SEQUENCE_NOFILE = (WM_CAP_START + 63); //没有文件
/// <summary>
/// 设置安装次序 WM_CAP_START + 64=1088
/// </summary>
public const int WM_CAP_SET_SEQUENCE_SETUP = (WM_CAP_START + 64); //设置安装次序
/// <summary>
/// 获得安装次序 WM_CAP_START + 65=1089
/// </summary>
public const int WM_CAP_GET_SEQUENCE_SETUP = (WM_CAP_START + 65); //获得安装次序
/// <summary>
/// 设置媒体控制接口 WM_CAP_START + 66=1090
/// </summary>
public const int WM_CAP_SET_MCI_DEVICE = (WM_CAP_START + 66); //设置媒体控制接口
/// <summary>
/// 获得媒体控制接口 WM_CAP_START + 67=1091
/// </summary>
public const int WM_CAP_GET_MCI_DEVICE = (WM_CAP_START + 67); //获得媒体控制接口
/// <summary>
/// 停止 WM_CAP_START + 68=1092
/// </summary>
public const int WM_CAP_STOP = (WM_CAP_START + 68); //停止
/// <summary>
/// 异常中断 WM_CAP_START + 69=1093
/// </summary>
public const int WM_CAP_ABORT = (WM_CAP_START + 69); //异常中断
/// <summary>
/// 打开单一的结构 WM_CAP_START + 68=1094
/// </summary>
public const int WM_CAP_SINGLE_FRame_OPEN = (WM_CAP_START + 70); //打开单一的结构
/// <summary>
/// 关闭单一的结构 WM_CAP_START + 71=1095
/// </summary>
public const int WM_CAP_SINGLE_FRame_CLOSE = (WM_CAP_START + 71); //关闭单一的结构
/// <summary>
/// 单一的结构 WM_CAP_START + 72=1096
/// </summary>
public const int WM_CAP_SINGLE_FRame = (WM_CAP_START + 72); //单一的结构
/// <summary>
/// 打开视频 WM_CAP_START + 80=1104
/// </summary>
public const int WM_CAP_PAL_OPEN = (WM_CAP_START + 80); //打开视频
/// <summary>
/// 保存视频 WM_CAP_START + 81=1105
/// </summary>
public const int WM_CAP_PAL_SAVE = (WM_CAP_START + 81); //保存视频
/// <summary>
/// 粘贴视频 WM_CAP_START + 82=1106
/// </summary>
public const int WM_CAP_PAL_PASTE = (WM_CAP_START + 82); //粘贴视频
/// <summary>
/// 自动创造 WM_CAP_START + 83=1107
/// </summary>
public const int WM_CAP_PAL_AUTOCREATE = (WM_CAP_START + 83); //自动创造
/// <summary>
/// 手动创造 WM_CAP_START + 84=1108
/// </summary>
public const int WM_CAP_PAL_MANUALCREATE = (WM_CAP_START + 84); //手动创造

// Following added post VFW 1.1
/// <summary>
/// 设置收回的错误 WM_CAP_START + 85=1109
/// </summary>
public const int WM_CAP_SET_CALLBACK_CAPCONTROL = (WM_CAP_START + 85); // 设置收回的错误

public const int WM_CAP_END = WM_CAP_SET_CALLBACK_CAPCONTROL;

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

#region 公共函数
//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, 0, 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);
}
#endregion 公共函数
#region 结构 VIDEOHDR|BITMAPINFOHEADER|BITMAPINFO|CAPTUREPARMS|CAPDRIVERCAPS|CAPSTATUS
//========================================================VideoHdr 结构=====================================================================
//VideoHdr 结构 定义了视频数据块的头信息，在编写回调函数时常用到其数据成员lpData（指向数据缓存的指针）和dwBufferLength（数据缓存的大小）。
//视频帧到缓存的捕获则需要应用回调函数和相应的数据块结构 VIDEOHDR
[StructLayout(LayoutKind.Sequential)]
public struct VIDEOHDR
{
public IntPtr lpData; /* 指向数据缓存的指针 */
public int dwBufferLength; /* 数据缓存的大小 */
public int dwBytesUsed; /* Bytes actually used */
public int dwTimeCaptured; /* Milliseconds from start of stream */
public int dwUser; /* for client's use */
public int dwFlags; /* assorted flags (see defines) */
public int dwReserved; /* reserved for driver */
}
//=======================================================BitmapInfoHeader结构===================================================================
//BitmapInfoHeader定义了位图的头部信息
[StructLayout(LayoutKind.Sequential)]
public struct BITMAPINFOHEADER
{
public int biSize;
public int biWidth;
public int biHeight;
public short biPlanes;
public short biBitCount;
public int biCompression;
public int biSizeImage;
public int biXPelsPerMeter;
public int biYPelsPerMeter;
public int biClrUsed;
public int biClrImportant;
}
//=========================================================================================================================================

//======================================================BitmapInfo结构=====================================================================
//BitmapInfo 位图信息
[StructLayout(LayoutKind.Sequential)]
public struct BITMAPINFO
{
public BITMAPINFOHEADER bmiHeader;
public int bmiColors;
}

//=====================================================CAPTUREPARMS结构======================================================================
//CAPTUREPARMS 包含控制视频流捕获过程的参数，如捕获帧频、指定键盘或鼠标键以终止捕获、捕获时间限制等；
[StructLayout(LayoutKind.Sequential)]
public struct CAPTUREPARMS
{
public int dwRequestMicroSecPerFrame; // 期望的桢播放率，以毫秒为单位，默认为66667，相当于15桢每秒。
public bool fMakeUserHitOKToCapture; // Show "Hit OK to cap" dlg?开始捕获标志位，如果值为真，则在开始捕获前要产生一个询问对话框，默认为假。
public uint wPercentDropForError; //所允许的最大丢桢百分比，可以从0变化到100，默认值为10。
public bool fYield; /*另起线程标志位，如果为真，则程序重新启动一个线程用于视频流的捕获，默认值是假。
但是如果你是为了真，你必须要在程序中处理一些潜在的操作，因为当视频捕获时，其他操作并没有被屏蔽。*/
public int dwIndexSize; // 在AVI文件中所允许的最大数目的索引项(32K)
public uint wChunkGranularity; // AVI文件的逻辑尺寸，以字节为单位。如果值是0，则说明该尺寸渐增 在 Win32程序中无用。(2K)
public bool fUsingDOSMemory; // Use DOS buffers?
public uint wNumVideoRequested; // 所被允许分配的最大视频缓存
public bool fCaptureAudio; // 音频标志位，如果音频流正在捕获，则该值为真。
public uint wNumAudioRequested; // 最大数量的音频缓存，默认值为10。
public uint vKeyAbort; // 终止流捕获的虚拟键盘码，默认值为VK_ESCAPE
[MarshalAs(UnmanagedType.Bool)]
public bool fAbortLeftMouse; // 终止鼠标左键标志位，如果该值为真，则在流捕获过程中如果点击鼠标左键则该捕获终止，默认值为真。
public bool fAbortRightMouse; // Abort on right mouse?
public bool fLimitEnabled; // 捕获操作时间限制，如果为真，则时间到了以后捕获操作终止，默认为假
public uint wTimeLimit; // 具体终止时间，只有 fLimitEnabled是真时.该位才有效
public bool fMCIControl; // Use MCI video source?
public bool fStepMCIDevice; // Step MCI device?MCI 设备标志。
public int dwMCIStartTime; // Time to start in MS
public int dwMCIStopTime; // Time to stop in MS
public bool fStepCaptureAt2x; // Perform spatial averaging 2x
public int wStepCaptureAverageFrames; // 当基于平均采样来创建桢时，桢的采样时间，典型值是5
public int dwAudioBufferSize; // 音频缓存的尺寸，如果用默认值0，缓存尺寸是最大0.5秒，或10k字节。
public int fDisableWriteCache; // Attempt to disable write cache
public int AVStreamMaster; //音视频同步标志。
}
//=========================================================================================================================================

//=================================================CAPDRIVERCAPS结构=======================================================================
//CAPDRIVERCAPS定义了捕获驱动器的能力，如有无视频叠加能力、有无控制视频源、视频格式的对话框等；
[StructLayout(LayoutKind.Sequential)]
public struct CAPDRIVERCAPS
{
[MarshalAs(UnmanagedType.U2)]
public UInt16 wDeviceIndex; //捕获驱动器的索引值，该值可以由0到9变化。
[MarshalAs(UnmanagedType.Bool)]
public bool fHasOverlay; // 视频叠加标志，如果设备支持视频叠加这该位是真。
[MarshalAs(UnmanagedType.Bool)]
public bool fHasDlgVideoSource; //视频资源对话框标志位，如果设备支持视频选择、控制对话框，该值为真。
[MarshalAs(UnmanagedType.Bool)]
public bool fHasDlgVideoFormat; //视频格式对话框标志位，如果设备支持对视频格式对话框的选择，该位真。
[MarshalAs(UnmanagedType.Bool)]
public bool fHasDlgVideoDisplay; //视频展示对话框标志位，如果设备支持对视频捕获缓存区的重新播放，该位是真。
[MarshalAs(UnmanagedType.Bool)]
public bool fCaptureInitialized; //捕获安装标志位，如果捕获驱动器已经成功连接，该值为真。
//[MarshalAs(UnmanagedType.Bool)]
public bool fDriverSuppliesPalettes; //驱动器调色板标志位，如果驱动器能创建调色板，则该位是真。
[MarshalAs(UnmanagedType.I4)]
public int hVideoIn;
[MarshalAs(UnmanagedType.I4)]
public int hVideoOut;
[MarshalAs(UnmanagedType.I4)]
public int hVideoExtIn;
[MarshalAs(UnmanagedType.I4)]
public int hVideoExtOut;
}
//=========================================================================================================================================

//=====================================================CAPSTATUS结构========================================================================
//CAPSTATUS定义了捕获窗口的当前状态，如图像的宽、高等；
[StructLayout(LayoutKind.Sequential)]
public struct CAPSTATUS
{
public int uiImageWidth; //图像宽度
public int uiImageHeight; //图像高度
public bool fLiveWindow; //活动窗口标记，如果窗口正以预览的方式展示图像，那么该值为真
public bool fOverlayWindow; //叠加窗口标志位，如果正在使用硬件叠加，则该位是真。
public bool fScale; //输入所放标志位，如果窗口是正在缩放视频到客户区，那么该位是真。当使用硬件叠加时，改位无效。
public Point ptScroll; //被展示在窗口客户区左上角的那个象素的x、y坐标偏移量。
public bool fUsingDefaultPalette; //默认调色板标志位，如果捕获窗口正在使用当前默认调色板，该值为真
public bool fAudioHardware; // 音频硬件标志位，如果系统已经安装了音频硬件，该值为真。
public bool fCapFileExists; //捕获文件标志位，如果一个捕获文件已经被创建，该值为真
public int dwCurrentVideoFrame; // 当前或最近流捕获过程中，所处理的桢的数目。包括丢弃的桢。
public int dwCurrentVideoFramesDropped;//当前流捕获过程中丢弃的桢的数目。
public int dwCurrentWaveSamples; // # of wave samples cap'td
public int dwCurrentTimeElapsedMS; // 从当前流捕获开始计算，程序所用的时间，以毫秒为单位。
public IntPtr hPalCurrent; // 当前剪切板的句柄。
public bool fCapturingNow; // 捕获标志位，当捕获是正在进行时，改位是真
public int dwReturn; // 错误返回值，当你的应用程序不支持错误回调函数时可以应用改位
public int wNumVideoAllocated; // 被分配的视频缓存的数目。
public int wNumAudioAllocated; // 被分配的音频缓存的数目。
}
//=========================================================================================================================================

#endregion 结构 VIDEOHDR|BITMAPINFOHEADER|BITMAPINFO|CAPTUREPARMS|CAPDRIVERCAPS|CAPSTATUS

}
public class cVideo //视频类
{
public bool flag = true;
private IntPtr lwndC; //保存无符号句柄
private IntPtr mControlPtr; //保存管理指示器
private int mWidth;
private int mHeight;
public delegate void RecievedFrameEventHandler(byte[] data);
public event RecievedFrameEventHandler RecievedFrame;

public VideoAPI.CAPTUREPARMS Capparms;
private VideoAPI.FrameEventHandler mFrameEventHandler;
public VideoAPI.CAPDRIVERCAPS CapDriverCAPS;//捕获驱动器的能力，如有无视频叠加能力、有无控制视频源、视频格式的对话框等；
public VideoAPI.CAPSTATUS CapStatus;//该结构用于保存视频设备捕获窗口的当前状态，如图像的宽、高等
string strFileName;
public cVideo(IntPtr handle, int width, int height)
{
CapDriverCAPS = new VideoAPI.CAPDRIVERCAPS();//捕获驱动器的能力，如有无视频叠加能力、有无控制视频源、视频格式的对话框等；
CapStatus = new VideoAPI.CAPSTATUS();//该结构用于保存视频设备捕获窗口的当前状态，如图像的宽、高等
mControlPtr = handle; //显示视频控件的句柄
mWidth = width; //视频宽度
mHeight = height; //视频高度
}
/// <summary>
/// 打开视频设备
/// </summary>
public bool StartWebCam()
{
//byte[] lpszName = new byte[100];
//byte[] lpszVer = new byte[100];
//VideoAPI.capGetDriverDescriptionA(0, lpszName, 100, lpszVer, 100);
//this.lwndC = VideoAPI.capCreateCaptureWindowA(lpszName, VideoAPI.WS_CHILD | VideoAPI.WS_VISIBLE, 0, 0, mWidth, mHeight, mControlPtr, 0);
//if (VideoAPI.SendMessage(lwndC, VideoAPI.WM_CAP_DRIVER_CONNECT, 0, 0))
//{
// VideoAPI.SendMessage(lwndC, VideoAPI.WM_CAP_SET_PREVIEWRATE, 100, 0);
// VideoAPI.SendMessage(lwndC, VideoAPI.WM_CAP_SET_PREVIEW, true, 0);
// return true;
//}
//else
//{
// return false;
//}
this.lwndC = VideoAPI.capCreateCaptureWindow("", VideoAPI.WS_CHILD | VideoAPI.WS_VISIBLE, 0, 0, mWidth, mHeight, mControlPtr, 0);//AVICap类的捕捉窗口
VideoAPI.FrameEventHandler FrameEventHandler = new VideoAPI.FrameEventHandler(FrameCallback);
VideoAPI.SendMessage(this.lwndC, VideoAPI.WM_CAP_SET_CALLBACK_ERROR, 0, 0);//注册错误回调函数
VideoAPI.SendMessage(this.lwndC, VideoAPI.WM_CAP_SET_CALLBACK_STATUS, 0, 0);//注册状态回调函数
VideoAPI.SendMessage(this.lwndC, VideoAPI.WM_CAP_SET_CALLBACK_VIDEOSTREAM, 0, 0);//注册视频流回调函数
VideoAPI.SendMessage(this.lwndC, VideoAPI.WM_CAP_SET_CALLBACK_FRAME, 0, FrameEventHandler);//注册帧回调函数

//if (!CapDriverCAPS.fCaptureInitialized)//判断当前设备是否被其他设备连接已经连接
//{

if (VideoAPI.SendMessage(this.lwndC, VideoAPI.WM_CAP_DRIVER_CONNECT, 0, 0))
{
//-----------------------------------------------------------------------
VideoAPI.SendMessage(this.lwndC, VideoAPI.WM_CAP_DRIVER_GET_CAPS, VideoAPI.SizeOf(CapDriverCAPS), ref CapDriverCAPS);//获得当前视频 CAPDRIVERCAPS定义了捕获驱动器的能力，如有无视频叠加能力、有无控制视频源、视频格式的对话框等；
VideoAPI.SendMessage(this.lwndC, VideoAPI.WM_CAP_GET_STATUS, VideoAPI.SizeOf(CapStatus), ref CapStatus);//获得当前视频流的尺寸 存入CapStatus结构

VideoAPI.BITMAPINFO bitmapInfo = new VideoAPI.BITMAPINFO();//设置视频格式 (height and width in pixels, bits per frame).
bitmapInfo.bmiHeader = new VideoAPI.BITMAPINFOHEADER();
bitmapInfo.bmiHeader.biSize = VideoAPI.SizeOf(bitmapInfo.bmiHeader);
bitmapInfo.bmiHeader.biWidth = mWidth;
bitmapInfo.bmiHeader.biHeight = mHeight;
bitmapInfo.bmiHeader.biPlanes = 1;
bitmapInfo.bmiHeader.biBitCount = 24;
VideoAPI.SendMessage(this.lwndC, VideoAPI.WM_CAP_SET_PREVIEWRATE, 40, 0);//设置在PREVIEW模式下设定视频窗口的刷新率 设置每40毫秒显示一帧，即显示帧速为每秒25帧
VideoAPI.SendMessage(this.lwndC, VideoAPI.WM_CAP_SET_SCALE, 1, 0);//打开预览视频的缩放比例
VideoAPI.SendMessage(this.lwndC, VideoAPI.WM_CAP_SET_VIDEOFORMAT, VideoAPI.SizeOf(bitmapInfo), ref bitmapInfo);

this.mFrameEventHandler = new VideoAPI.FrameEventHandler(FrameCallback);
this.capSetCallbackOnFrame(this.lwndC, this.mFrameEventHandler);

VideoAPI.CAPTUREPARMS captureparms = new VideoAPI.CAPTUREPARMS();
VideoAPI.SendMessage(this.lwndC, VideoAPI.WM_CAP_GET_SEQUENCE_SETUP, VideoAPI.SizeOf(captureparms), ref captureparms);
if (CapDriverCAPS.fHasOverlay)
{
VideoAPI.SendMessage(this.lwndC, VideoAPI.WM_CAP_SET_OVERLAY, 1, 0);//启用叠加 注：据说启用此项可以加快渲染速度
}
VideoAPI.SendMessage(this.lwndC, VideoAPI.WM_CAP_SET_PREVIEW, 1, 0);//设置显示图像启动预览模式 PREVIEW
VideoAPI.SetWindowPos(this.lwndC, 0, 0, 0, mWidth, mHeight, VideoAPI.SWP_NOZORDER | VideoAPI.SWP_NOMOVE);//使捕获窗口与进来的视频流尺寸保持一致
return true;
}
else
{

flag = false;
return false;
}
}
public void get()
{
VideoAPI.SendMessage(this.lwndC, VideoAPI.WM_CAP_GET_SEQUENCE_SETUP, VideoAPI.SizeOf(Capparms), ref Capparms);
}
public void set()
{
VideoAPI.SendMessage(this.lwndC, VideoAPI.WM_CAP_SET_SEQUENCE_SETUP, VideoAPI.SizeOf(Capparms), ref Capparms);
}
private bool capSetCallbackOnFrame(IntPtr lwnd, VideoAPI.FrameEventHandler lpProc)
{
return VideoAPI.SendMessage(this.lwndC, VideoAPI.WM_CAP_SET_CALLBACK_FRAME, 0, lpProc);
}
/// <summary>
/// 关闭视频设备
/// </summary>
public void CloseWebcam()
{
VideoAPI.SendMessage(lwndC, VideoAPI.WM_CAP_DRIVER_DISCONNECT, 0, 0);
}
/// <summary>
/// 拍照
/// </summary>
/// <param>要保存bmp文件的路径</param>
public void GrabImage(IntPtr hWndC, string path)
{
IntPtr hBmp = Marshal.StringToHGlobalAnsi(path);
VideoAPI.SendMessage(lwndC, VideoAPI.WM_CAP_SAVEDIB, 0, hBmp.ToInt32());
}
public void StarKinescope(string path)
{
strFileName = path;
string dir = path.Remove(path.LastIndexOf("//"));
if (!File.Exists(dir))
{
Directory.CreateDirectory(dir);
}
int hBmp = Marshal.StringToHGlobalAnsi(path).ToInt32();
bool b = VideoAPI.SendMessage(this.lwndC, VideoAPI.WM_CAP_FILE_SET_CAPTURE_FILE, 0, hBmp);
b = VideoAPI.SendMessage(this.lwndC, VideoAPI.WM_CAP_SEQUENCE, 0, 0);
}
/// <summary>
/// 停止录像
/// </summary>
public void StopKinescope()
{
VideoAPI.SendMessage(lwndC, VideoAPI.WM_CAP_STOP, 0, 0);
}
private void FrameCallback(IntPtr lwnd, IntPtr lpvhdr)
{
VideoAPI.VIDEOHDR videoHeader = new VideoAPI.VIDEOHDR();
byte[] VideoData;
videoHeader = (VideoAPI.VIDEOHDR)VideoAPI.GetStructure(lpvhdr, videoHeader);
VideoData = new byte[videoHeader.dwBytesUsed];
VideoAPI.Copy(videoHeader.lpData, VideoData);
if (this.RecievedFrame != null)
this.RecievedFrame(VideoData);
}
}

}