C#实现摄像头调用、拍照

using System.Runtime.InteropServices;
using System.Drawing.Imaging;

namespace WindowsFormsApplication2
{
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;

///
/// 初始化摄像头
///
/// 控件的句柄
/// 开始显示的左边距
/// 开始显示的上边距
/// 要显示的宽度
/// 要显示的长度
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, int lParam);
///
/// 开始显示图像
///
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;
}
///
/// 停止显示
///
public void Stop()
{
SendMessage(hWndC, WM_CAP_DRIVER_DISCONNECT, 0, 0);
bStat = false;
}
///
/// 抓图
///
/// 要保存bmp文件的路径
public void GrabImage(string path)
// public void GrabImage( )
{
IntPtr hBmp = Marshal.StringToHGlobalAnsi(path);
SendMessage(hWndC, WM_CAP_SAVEDIB, 0, hBmp.ToInt32());
}

///
/// 录像
///
/// 要保存avi文件的路径
public void Kinescope(string path)
{
IntPtr hBmp = Marshal.StringToHGlobalAnsi(path);
SendMessage(hWndC, WM_CAP_FILE_SET_CAPTURE_FILEA, 0, hBmp.ToInt32());
SendMessage(hWndC, WM_CAP_SEQUENCE, 0, 0);
}
///
/// 停止录像
///
public void StopKinescope()
{
SendMessage(hWndC, WM_CAP_STOP, 0, 0);
}

}
}

aspx：

namespace WindowsFormsApplication2
{
public partial class Form1 : Form
{
Pick pick;
public Form1()
{
InitializeComponent();
}

private void button1_Click(object sender, EventArgs e)   //启动摄像头
{
pick = new Pick(panel1.Handle, 0, 0, panel1.Width, panel1.Height);
pick.Start();
pictureBox1.ImageLocation = null; //清空pictureBox1
}

private void button2_Click(object sender, EventArgs e) //停止摄像头
{
pick.Stop();
}

private void button3_Click(object sender, EventArgs e)  //退出界面
{
if (MessageBox.Show("退出本系统?", "提示", MessageBoxButtons.OKCancel, MessageBoxIcon.Question) == DialogResult.OK)
Application.Exit();
}

private void button4_Click(object sender, EventArgs e) //保存截图
{
string path;
SaveFileDialog sdf1 = new SaveFileDialog();
sdf1.Filter = "图片*.bmp;*.jpg;.jpeg;*.gif|*.bmp|所有文件(*.*)|*.*";
if (sdf1.ShowDialog() == DialogResult.OK)
{
path = sdf1.FileName;
pick.GrabImage(path);
pictureBox1.ImageLocation = path; //并显示在pictureBox1方框中
pictureBox1.Visible = true;
pick.Stop();
}
}
}
}