本文是借助avicap32.dll库来驱动摄像头。做到了抓图、录像功能。

using System;
   using System.Runtime.InteropServices;
   using System.Drawing;
   using System.Drawing.Imaging;  namespace using System;
   using System.Runtime.InteropServices;
   using System.Drawing;
   using System.Drawing.Imaging;  namespace PickHead
   {
   /// <summary>
   /// 一个控制摄像头的类
   /// </summary>
   public class Pick
   {
   private const int WM_USER = 0x400;
   private const int WS_CHILD = 0x40000000;
   private const int WS_VISIBLE = 0x10000000;
   private const int WM_CAP_START = WM_USER;
   private const int WM_CAP_STOP = WM_CAP_START + 68;
   private const int WM_CAP_DRIVER_CONNECT = WM_CAP_START + 10;
   private const int WM_CAP_DRIVER_DISCONNECT = WM_CAP_START + 11;
   private const int WM_CAP_SAVEDIB = WM_CAP_START + 25;
   private const int WM_CAP_GRAB_FRAME = WM_CAP_START + 60;
   private const int WM_CAP_SEQUENCE = WM_CAP_START + 62;
   private const int WM_CAP_FILE_SET_CAPTURE_FILEA = WM_CAP_START + 20;
   private const int WM_CAP_SEQUENCE_NOFILE =WM_CAP_START+ 63;
   private const int WM_CAP_SET_OVERLAY =WM_CAP_START+ 51; 
   private const int WM_CAP_SET_PREVIEW =WM_CAP_START+ 50; 
   private const int WM_CAP_SET_CALLBACK_VIDEOSTREAM = WM_CAP_START +6;
   private const int WM_CAP_SET_CALLBACK_ERROR=WM_CAP_START +2;
   private const int WM_CAP_SET_CALLBACK_STATUSA= WM_CAP_START +3;
   private const int WM_CAP_SET_CALLBACK_FRAME= WM_CAP_START +5;
   private const int WM_CAP_SET_SCALE=WM_CAP_START+ 53;
   private const int WM_CAP_SET_PREVIEWRATE=WM_CAP_START+ 52; 
   private IntPtr hWndC;
   private bool bStat = false;
   
   private IntPtr mControlPtr;
   private int mWidth;
   private int mHeight;
   private int mLeft;
   private int mTop;
   
   /// <summary>
   /// 初始化摄像头
   /// </summary>
   /// <param name="handle">控件的句柄</param>
   /// <param name="left">开始显示的左边距</param>
   /// <param name="top">开始显示的上边距</param>
   /// <param name="width">要显示的宽度</param>
   /// <param name="height">要显示的长度</param>
   public Pick(IntPtr handle, int left, int top, int width,int height)
   {
   mControlPtr = handle;
   mWidth = width;
   mHeight = height;
     mLeft = left;
   mTop = top;
   }  [DllImport("avicap32.dll")] 
   private static extern IntPtr capCreateCaptureWindowA(byte[] lpszWindowName, int dwStyle, int x, int y, int nWidth, int nHeight, IntPtr hWndParent, int nID);
   
   [DllImport("avicap32.dll")]
   private static extern int capGetVideoFormat(IntPtr hWnd, IntPtr psVideoFormat, int wSize );
   [DllImport("User32.dll")] 
   private static extern bool SendMessage(IntPtr hWnd, int wMsg, int wParam, long lParam);  /// <summary>
   /// 开始显示图像
   /// </summary>
   public void Start()
   {
   if (bStat)
   return;
   
   bStat = true;
   byte[] lpszName = new byte[100];
   
   hWndC = capCreateCaptureWindowA(lpszName,WS_CHILD|WS_VISIBLE ,mLeft,mTop,mWidth,mHeight,mControlPtr,0);  if (hWndC.ToInt32() != 0)
   {
   SendMessage(hWndC, WM_CAP_SET_CALLBACK_VIDEOSTREAM, 0, 0);
   SendMessage(hWndC, WM_CAP_SET_CALLBACK_ERROR, 0, 0);
   SendMessage(hWndC, WM_CAP_SET_CALLBACK_STATUSA, 0, 0);
   SendMessage(hWndC, WM_CAP_DRIVER_CONNECT, 0, 0);
   SendMessage(hWndC, WM_CAP_SET_SCALE, 1, 0);
   SendMessage(hWndC, WM_CAP_SET_PREVIEWRATE, 66, 0);
   SendMessage(hWndC, WM_CAP_SET_OVERLAY, 1, 0);
   SendMessage(hWndC, WM_CAP_SET_PREVIEW, 1, 0);
   }  return;
  }
  /// <summary>
   /// 停止显示   /// </summary>
   public void Stop()
   {
   SendMessage(hWndC, WM_CAP_DRIVER_DISCONNECT, 0, 0);
   bStat = false;
   }  /// <summary>
   /// 抓图
   /// </summary>
   /// <param name="path">要保存bmp文件的路径</param>
   public void GrabImage(string path)
   {
   
   IntPtr hBmp = Marshal.StringToHGlobalAnsi(path);
   SendMessage(hWndC,WM_CAP_SAVEDIB,0,hBmp.ToInt64());  }
  /// <summary>
   /// 录像
   /// </summary>
   /// <param name="path">要保存avi文件的路径</param>
   public void Kinescope(string path)
   {
   IntPtr hBmp = Marshal.StringToHGlobalAnsi(path);
   SendMessage(hWndC,WM_CAP_FILE_SET_CAPTURE_FILEA,0,hBmp.ToInt64());
   SendMessage(hWndC, WM_CAP_SEQUENCE, 0, 0);
   }  /// <summary>
   /// 停止录像
   /// </summary>
   public void StopKinescope()
   {
   SendMessage(hWndC, WM_CAP_STOP, 0, 0);
   }  }
   }