一个用于驱动摄像头的类

 

 
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); 
} 

} 
}