C#摄像头编程实例

作者：李君老师

转自：http://blog.sina.com.cn/s/blog_4b57e1d4010008v7.html

安装摄像头后，一般可以找到一个avicap32.dll文件,此文件中封装了对摄像头的相关操作API

然后自己写一个关于摄像头的类

using system;

using System.Runtime.InteropServices;

namespace webcam

{

///

/// avicap 的摘要说明。

///

public class showVideo

{

// showVideo calls

[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 );

// constants

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;

// Structures

[StructLayout(LayoutKind.Sequential)] 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=4)] public int[] dwReserved;

}

[structlayout(layoutkind.sequential)] 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)] public struct bitmapinfo

{

[MarshalAs(UnmanagedType.Struct, SizeConst=40)] public BITMAPINFOHEADER bmiHeader;

[MarshalAs(UnmanagedType.ByValArray, SizeConst=1024)] public Int32[] bmiColors;

}

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

// Public methods

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);

}

}

//web camera class

public class WebCamera

{

// Constructur

public WebCamera(IntPtr handle, int width,int height)

{

mControlPtr = handle;

mWidth = width;

mHeight = height;

}

// delegate for frame callback

public delegate void RecievedFrameEventHandler(byte[] data);

public event RecievedFrameEventHandler RecievedFrame;

private IntPtr lwndC; // Holds the unmanaged handle of the control

private IntPtr mControlPtr; // Holds the managed pointer of the control

private int mWidth;

private int mHeight;

private showVideo.FrameEventHandler mFrameEventHandler; // Delegate instance for the frame callback - must keep alive! gc should NOT collect it

// Close the web camera

public void CloseWebcam()

{

this.capDriverDisconnect(this.lwndC);

}

// start the web camera

public void StartWebCam()

{

byte[] lpszName = new byte[100];

byte[] lpszVer = new byte[100];

showVideo.capGetDriverDescriptionA(0, lpszName, 100,lpszVer, 100);

this.lwndC = showVideo.capCreateCaptureWindowA(lpszName, showVideo.WS_VISIBLE + showVideo.WS_CHILD, 0, 0, mWidth, mHeight, mControlPtr, 0);

if (this.capDriverConnect(this.lwndC, 0))

{

this.capPreviewRate(this.lwndC, 66);

this.capPreview(this.lwndC, true);

showVideo.BITMAPINFO bitmapinfo = new showVideo.BITMAPINFO();

bitmapinfo.bmiHeader.biSize = showVideo.SizeOf(bitmapinfo.bmiHeader);

bitmapinfo.bmiHeader.biWidth = 352;

bitmapinfo.bmiHeader.biHeight = 288;

bitmapinfo.bmiHeader.biPlanes = 1;

bitmapinfo.bmiHeader.biBitCount = 24;

this.capSetVideoFormat(this.lwndC, ref bitmapinfo, showVideo.SizeOf(bitmapinfo));

this.mFrameEventHandler = new showVideo.FrameEventHandler(FrameCallBack);

this.capSetCallbackOnFrame(this.lwndC, this.mFrameEventHandler);

showVideo.SetWindowPos(this.lwndC, 0, 0, 0, mWidth , mHeight , 6);

}

}

// private functions

private bool capDriverConnect(IntPtr lwnd, short i)

{

return showVideo.SendMessage(lwnd, showVideo.WM_CAP_DRIVER_CONNECT, i, 0);

}

private bool capdriverdisconnect(intptr lwnd)

{

return showVideo.SendMessage(lwnd, showVideo.WM_CAP_DRIVER_DISCONNECT, 0, 0);

}

private bool capPreview(IntPtr lwnd, bool f)

{

return showVideo.SendMessage(lwnd, showVideo.WM_CAP_SET_PREVIEW , f, 0);

}

private bool cappreviewrate(intptr lwnd, short wms)

{

return showVideo.SendMessage(lwnd, showVideo.WM_CAP_SET_PREVIEWRATE, wMS, 0);

}

private bool capSetCallbackOnFrame(IntPtr lwnd, showVideo.FrameEventHandler lpProc)

{

return showVideo.SendMessage(lwnd, showVideo.WM_CAP_SET_CALLBACK_FRAME, 0, lpProc);

}

private bool capsetvideoformat(intptr hcapwnd, ref showvideo.bitmapinfo bmpformat, int capformatsize)

{

return showVideo.SendMessage(hCapWnd, showVideo.WM_CAP_SET_VIDEOFORMAT, CapFormatSize, ref BmpFormat);

}

private void framecallback(intptr lwnd, intptr lpvhdr)

{

showVideo.VIDEOHDR videoHeader = new showVideo.VIDEOHDR();

byte[] VideoData;

videoHeader = (showVideo.VIDEOHDR)showVideo.GetStructure(lpVHdr,videoHeader);

VideoData = new byte[videoHeader.dwBytesUsed];

showVideo.Copy(videoHeader.lpData ,VideoData);

if (this.RecievedFrame != null)

this.RecievedFrame (VideoData);

}

}

}

然后再写一个测试窗体

using system;

using System.Drawing;

using System.Collections;

using System.ComponentModel;

using System.Windows.Forms;

using System.Data;

using webcam;

namespace webcam

{

///

/// Form1 的摘要说明。

///

public class Form1 : System.Windows.Forms.Form

{

private System.Windows.Forms.Panel panelPreview;

private System.Windows.Forms.Button b_play;

private System.Windows.Forms.Button b_stop;

///

/// 必需的设计器变量。

///

private System.ComponentModel.Container components = null;

WebCamera wc;

public form1()

{

//

// Windows 窗体设计器支持所必需的

//

InitializeComponent();

//

// TODO: 在 InitializeComponent 调用后添加任何构造函数代码

//

}

///

/// 清理所有正在使用的资源。

///

protected override void Dispose( bool disposing )

{

if( disposing )

{

if (components != null)

{

components.Dispose();

}

}

base.Dispose( disposing );

}

#region windows 窗体设计器生成的代码

///

/// 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。

///

private void InitializeComponent()

{

this.b_play = new System.Windows.Forms.Button();

this.panelPreview = new System.Windows.Forms.Panel();

this.b_stop = new System.Windows.Forms.Button();

this.SuspendLayout();

//

// b_play

//

this.b_play.Location = new System.Drawing.Point(280, 368);

this.b_play.Name = "b_play";

this.b_play.TabIndex = 0;

this.b_play.Text = "&Play";

this.b_play.Click += new System.EventHandler(this.button1_Click);

//

// panelPreview

//

this.panelPreview.Location = new System.Drawing.Point(8, 8);

this.panelPreview.Name = "panelPreview";

this.panelPreview.Size = new System.Drawing.Size(344, 272);

this.panelPreview.TabIndex = 1;

//

// b_stop

//

this.b_stop.Enabled = false;

this.b_stop.Location = new System.Drawing.Point(360, 368);

this.b_stop.Name = "b_stop";

this.b_stop.TabIndex = 2;

this.b_stop.Text = "&Stop";

this.b_stop.Click += new System.EventHandler(this.b_stop_Click);

//

// Form1

//

this.AutoScaleBaseSize = new System.Drawing.Size(6, 14);

this.ClientSize = new System.Drawing.Size(464, 413);

this.Controls.Add(this.b_stop);

this.Controls.Add(this.panelPreview);

this.Controls.Add(this.b_play);

this.MaximizeBox = false;

this.MinimizeBox = false;

this.Name = "Form1";

this.Text = "GoodView test Web Camera";

this.Load += new System.EventHandler(this.Form1_Load);

this.ResumeLayout(false);

}

#endregion

///

/// 应用程序的主入口点。

///

[STAThread]

static void Main()

{

Application.Run(new Form1());

}

private void form1_load(object sender, system.eventargs e)

{

b_play.Enabled = false;

b_stop.Enabled = true;

panelPreview.Size = new Size(330,330);

wc = new WebCamera( panelPreview.Handle,panelPreview.Width,panelPreview.Height);

wc.StartWebCam();

}

private void button1_click(object sender, system.eventargs e)

{

b_play.Enabled = false;

b_stop.Enabled = true;

panelPreview.Size = new Size(330,330);

wc = new WebCamera( panelPreview.Handle,panelPreview.Width,panelPreview.Height);

wc.StartWebCam();

}

private void b_stop_click(object sender, system.eventargs e)

{

b_play.Enabled = true;

b_stop.Enabled = false;

wc.CloseWebcam();

}

}

}

就可以了!不知哪位有没有写录像的经验,可以交流一下,将摄像头中的数据存为视频!!