webcam with no user input?

Hey guys. ive been steaming on this one for quite some time. Ive got a program that relies on remote control of the computer, and i need to be able to take a webcam image without the user having to press buttons etc. So far, ive gotten to the point where i can find my webcam, and with the help of a button, start a preview, then take the picture and save it as a jpeg.

Problem is, when you press the button to start the preview, another dialog box shows up (not related to my code) prompting me to select a video source..

Im confused kus it seems as though the list i find on form_load does nothing at all if when i press the button it prompts me with the same list.

Well you can infer from this that i cannot use the btnstart_click(sender, e) on form_load because it opens a dialog that wont close until i press ok, and i already tried to sendkeys enter, it didnt work.

anyone have any idea how i can either alter my code, or make new code to take a web cam image, and save it with no user input?

heres my code:
(keep in mind i did not write this, i found it from this link which i believe found it from another forum.)
http://www.dreamincode.net/forums/showtopic106157.htm

Code:

---

Imports System.Runtime.InteropServices

Public Class Form1

    Const WM_CAP As Short = &H400S

    Const WM_CAP_DRIVER_CONNECT As Integer = WM_CAP + 10
    Const WM_CAP_DRIVER_DISCONNECT As Integer = WM_CAP + 11
    Const WM_CAP_EDIT_COPY As Integer = WM_CAP + 30

    Const WM_CAP_SET_PREVIEW As Integer = WM_CAP + 50
    Const WM_CAP_SET_PREVIEWRATE As Integer = WM_CAP + 52
    Const WM_CAP_SET_SCALE As Integer = WM_CAP + 53
    Const WS_CHILD As Integer = &H40000000
    Const WS_VISIBLE As Integer = &H10000000
    Const SWP_NOMOVE As Short = &H2S
    Const SWP_NOSIZE As Short = 1
    Const SWP_NOZORDER As Short = &H4S
    Const HWND_BOTTOM As Short = 1

    Dim iDevice As Integer = 0 ' Current device ID
    Dim hHwnd As Integer ' Handle to preview window

    Declare Function SendMessage Lib "user32" Alias "SendMessageA" _
        (ByVal hwnd As Integer, ByVal wMsg As Integer, ByVal wParam As Integer, _
        <MarshalAs(UnmanagedType.AsAny)> ByVal lParam As Object) As Integer

    Declare Function SetWindowPos Lib "user32" Alias "SetWindowPos" (ByVal hwnd As Integer, _
        ByVal hWndInsertAfter As Integer, ByVal x As Integer, ByVal y As Integer, _
        ByVal cx As Integer, ByVal cy As Integer, ByVal wFlags As Integer) As Integer

    Declare Function DestroyWindow Lib "user32" (ByVal hndw As Integer) As Boolean

    Declare Function capCreateCaptureWindowA Lib "avicap32.dll" _
        (ByVal lpszWindowName As String, ByVal dwStyle As Integer, _
        ByVal x As Integer, ByVal y As Integer, ByVal nWidth As Integer, _
        ByVal nHeight As Short, ByVal hWndParent As Integer, _
        ByVal nID As Integer) As Integer

    Declare Function capGetDriverDescriptionA Lib "avicap32.dll" (ByVal wDriver As Short, _
        ByVal lpszName As String, ByVal cbName As Integer, ByVal lpszVer As String, _
        ByVal cbVer As Integer) As Boolean

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        LoadDeviceList()
        If lstDevices.Items.Count > 0 Then
            btnStart.Enabled = True
            lstDevices.SelectedIndex = 0
            btnStart.Enabled = True
        Else
            lstDevices.Items.Add("No Capture Device")
            btnStart.Enabled = False
        End If
        btnStop.Enabled = False
        btnSave.Enabled = False
        'picCapture.SizeMode = PictureBoxSizeMode.StretchImage
        picCapture.SizeMode = PictureBoxSizeMode.AutoSize
    End Sub

    Private Sub LoadDeviceList()
        Dim strName As String = Space(100)
        Dim strVer As String = Space(100)
        Dim bReturn As Boolean
        Dim x As Integer = 0

        '
        ' Load name of all avialable devices into the lstDevices
        '

        Do
            '
            '  Get Driver name and version
            '
            bReturn = capGetDriverDescriptionA(x, strName, 100, strVer, 100)

            '
            ' If there was a device add device name to the list
            '
            If bReturn Then lstDevices.Items.Add(strName.Trim)
            x += 1
        Loop Until bReturn = False
    End Sub

    Private Sub OpenPreviewWindow()
        Dim iHeight As Integer = picCapture.Height
        Dim iWidth As Integer = picCapture.Width

        '
        ' Open Preview window in picturebox
        '
        hHwnd = capCreateCaptureWindowA(iDevice, WS_VISIBLE Or WS_CHILD, 0, 0, 640, _
            480, picCapture.Handle.ToInt32, 0)

        '
        ' Connect to device
        '
        If SendMessage(hHwnd, WM_CAP_DRIVER_CONNECT, iDevice, 0) Then
            '
            'Set the preview scale
            '
            SendMessage(hHwnd, WM_CAP_SET_SCALE, True, 0)

            '
            'Set the preview rate in milliseconds
            '
            SendMessage(hHwnd, WM_CAP_SET_PREVIEWRATE, 66, 0)

            '
            'Start previewing the image from the camera
            '
            SendMessage(hHwnd, WM_CAP_SET_PREVIEW, True, 0)

            '
            ' Resize window to fit in picturebox
            '
            SetWindowPos(hHwnd, HWND_BOTTOM, 0, 0, 640, 480, _
                    SWP_NOMOVE Or SWP_NOZORDER)

            btnSave.Enabled = True
            btnStop.Enabled = True
            btnStart.Enabled = False
        Else
            '
            ' Error connecting to device close window
            '
            DestroyWindow(hHwnd)

            btnSave.Enabled = False
        End If
    End Sub

    Private Sub btnStart_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnStart.Click
        iDevice = lstDevices.SelectedIndex
        OpenPreviewWindow()
    End Sub

    Private Sub ClosePreviewWindow()
        '
        ' Disconnect from device
        '
        SendMessage(hHwnd, WM_CAP_DRIVER_DISCONNECT, iDevice, 0)

        '
        ' close window
        '

        DestroyWindow(hHwnd)
    End Sub

    Private Sub btnStop_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnStop.Click
        ClosePreviewWindow()
        btnSave.Enabled = False
        btnStart.Enabled = True
        btnStop.Enabled = False
    End Sub

    Private Sub btnSave_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSave.Click
        Dim data As IDataObject
        Dim bmap As Image

        '
        ' Copy image to clipboard
        '
        SendMessage(hHwnd, WM_CAP_EDIT_COPY, 640, 480)

        '
        ' Get image from clipboard and convert it to a bitmap
        '
        data = Clipboard.GetDataObject()
        If data.GetDataPresent(GetType(System.Drawing.Bitmap)) Then
            bmap = CType(data.GetData(GetType(System.Drawing.Bitmap)), Image)
            picCapture.Image = bmap
            ClosePreviewWindow()
            btnSave.Enabled = False
            btnStop.Enabled = False
            btnStart.Enabled = True

            bmap.Save("C:\Screenshots\pic.jpg")

        End If
    End Sub
End Class

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i don't have the patience to look through your code right now :eek2: and it maybe something simple to stop the 3rd party window coming up!

but i would recommend you have a look at ezvidcap by Ray Mercer. Although it is quite old now and coded in VB6, I have used it in previous projects in .Net flawlessly. It also has alot of functions already coded which you may require.

If you do use this control then you can make use of the image capture features by simply calling the method for it remotly etc.

http://www.shrinkwrapvb.com/ezvidcap.htm

Good Luck

hey. thanks for replying.

i dont rly want to download source.

maybe if there is source on the web page, il take a look at it for ideas, but i was hoping for some tips on how to ge this done without thousands of lines of unnecessary code. So far, ive been able to use my code provided, with some tweaks and timers added, to provide a 'fake' user. ive kept the buttons, and simply called them based on a timer. problem is, it works on my laptop, but when i run it on my desktop, the image is saved as a green blank page.

This is most likely due to the fact that i ignore the third party msgbox, and simply focus on the form instead. So what i truely need from you guys, is a modified version of the code i have, so that buttons are no longer needed, or more code that works with 2008 with no buttons! :]

thanks