Trigger event when Picturebox Image changed from its Handle

I am accessing the Webcam through "avicap32" dll file in C# and i followed the code from here. Webcam starts and its LED become active Interesting point is that image is nor set with Image property neither with BackgroundImage property it is set via picturebox Handle. Picturebox is not visible & Webcam light stays active but there is not event of picturebox that triggers when its image got changed via its Handle

what i already tried is

  • Picturebox BackgroundImageChanged Event (Not firing)
  • Picturebox Paint Event (Also not firing)

    i can implement a timer/thread/background-worker to get images from picturebox at regular interval but due to performance issue i would like to apply event oriented approach. The code for connecting to Webcam is following

    public void OpenConnection()
    {
        string DeviceIndex = Convert.ToString(DeviceID);
        IntPtr oHandle = Container.Handle;
    
    hHwnd = capCreateCaptureWindowA(ref DeviceIndex, WS_VISIBLE | WS_CHILD, 0, 0, 640, 480, oHandle.ToInt32(), 0);
    
         // Connect to device
       if (SendMessage(hHwnd, WM_CAP_DRIVER_CONNECT, DeviceID, 0) != 0)
        {
             // Set the preview scale
           SendMessage(hHwnd, WM_CAP_SET_SCALE, -1, 0);
            // Set the preview rate in terms of milliseconds
            SendMessage(hHwnd, WM_CAP_SET_PREVIEWRATE, 66, 0);
    
             // Start previewing the image from the camera
           SendMessage(hHwnd, WM_CAP_SET_PREVIEW, -1, 0);
    
     // Resize window to fit in picturebox
     SetWindowPos(hHwnd, HWND_BOTTOM, 0, 0, Container.Height, Container.Width, SWP_NOMOVE | SWP_NOZORDER);
    
        }
           else
        {
            // Error connecting to device close window
            DestroyWindow(hHwnd);
        }
    }
    
  • any other solution will be welcomed only if it is native or with out any other external library as i have already explored & used other approaches like Aforge and OpenCV but these are not the requirements

    链接地址: http://www.djcxy.com/p/81048.html

    上一篇: 在Windows应用商店应用程序中捕获无声音视频

    下一篇: 当Picturebox图像从其手柄改变时触发事件