/// <summary>
/// 启动摄像头
/// </summary>
public void Open()
{
if (State != CameraState.Closed)
{
return;
}
//创建视频窗口
_captureWindowHandle = AviCap32Helper.capCreateCaptureWindowA(
"",
AviCap32Helper.WS_VISIBLE + AviCap32Helper.WS_CHILD,
0,
0,
_windowWidth,
_windowHeight,
_controlHandle,
0);
//连接设备
if (CapDriverConnect(_captureWindowHandle, 0))
{
//获得当前视频 CAPDRIVERCAPS定义了捕获驱动器的能力，如有无视频叠加能力、有无控制视频源、视频格式的对话框等
//AviCap32Helper.SendMessage(_captureWindowHandle, AviCap32Helper.WM_CAP_DRIVER_GET_CAPS, AviCap32Helper.SizeOf(_capDriverCAPS), ref _capDriverCAPS);
//获得当前视频流的尺寸 存入CapStatus结构
AviCap32Helper.SendMessage(_captureWindowHandle, AviCap32Helper.WM_CAP_GET_STATUS, AviCap32Helper.SizeOf(_capStatus), ref _capStatus);
//if (CameraConnected != null)
//{
// CameraConnected(new CameraConntectedEventArgs()
// {
// ImageWidth = _capStatus.uiImageWidth,
// ImageHeight = _capStatus.uiImageHeight
// });
//}
_imageX = (_windowWidth - _capStatus.uiImageWidth) / 2;
_imageY = (_windowHeight - _capStatus.uiImageHeight) / 2;
_imageWidth = Math.Min(_windowWidth, _capStatus.uiImageWidth);
_imageHeight = Math.Min(_windowHeight, _capStatus.uiImageHeight);
//调整视口的位置和大小
AviCap32Helper.SetWindowPos(_captureWindowHandle, 0, _imageX, _imageY, _capStatus.uiImageWidth, _capStatus.uiImageHeight, 0);
//设置视频格式
//AviCap32Helper.BITMAPINFO bitmapInfo = new AviCap32Helper.BITMAPINFO();
//bitmapInfo.bmiHeader = new AviCap32Helper.BITMAPINFOHEADER();
//bitmapInfo.bmiHeader.biSize = AviCap32Helper.SizeOf(bitmapInfo.bmiHeader);
//bitmapInfo.bmiHeader.biWidth = 50;
//bitmapInfo.bmiHeader.biHeight = 50;
//bitmapInfo.bmiHeader.biPlanes = 1;
//bitmapInfo.bmiHeader.biBitCount = 24;
//CapSetVideoFormat(_captureWindowHandle, ref bitmapInfo, AviCap32Helper.SizeOf(bitmapInfo));
//设置在PREVIEW模式下设定视频窗口的刷新率 设置每50毫秒显示一帧，即显示帧速为每秒20帧
CapSetPreviewRate(_captureWindowHandle, 50);
//打开预览视频的缩放功能
//AviCap32Helper.SendMessage(_captureWindowHandle, AviCap32Helper.WM_CAP_SET_SCALE, 1, 0);
CapSetPreview(_captureWindowHandle, true);
_frameEventHandler = new AviCap32Helper.FrameEventHandler(FrameCallBack);
CapSetCallbackFrame(_captureWindowHandle, _frameEventHandler);
State = CameraState.Opend;
}
else
{
throw new Exception("无法连接摄像头");
}
}
//设置获取帧的回调
private bool CapSetCallbackFrame(IntPtr lwnd, AviCap32Helper.FrameEventHandler lpProc)
{
return(AviCap32Helper.SendMessage(lwnd, AviCap32Helper.WM_CAP_SET_CALLBACK_FRAME, 0, lpProc));
}
