public Form1()
{
InitializeComponent();
}
cVideo video;
private void Form1_Load(object sender, EventArgs e)
{
}
private void button1_Click(object sender, EventArgs e)
{
video = new cVideo(pictureBox1.Handle, pictureBox1.Width, pictureBox1.Height);
video.StartWebCam();
}
private void button2_Click(object sender, EventArgs e)
{
video.CloseWebcam();
}
private void button3_Click(object sender, EventArgs e)
{
video.GrabImage(video.GetIntPtr(), "d:\\a.bmp");
}
}
public class VideoAPI
{
// 视频API调用
[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);
// 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 class cVideo
{
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 cVideo(IntPtr handle, int width, int height)
{
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 void 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);
}
}
public IntPtr GetIntPtr()
{
byte[] lpszName = new byte[100];
return VideoAPI.capCreateCaptureWindowA(lpszName,
VideoAPI.WS_CHILD | VideoAPI.WS_VISIBLE, 0, 0,
mWidth, mHeight, mControlPtr, 0);
}
/// <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 name="path">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());
}
}
怎么获取不到图像？？？？？
