Too much code?? I think i zigged when i should have zagged

[cjbeck]

Ok, Here is my process... this will probably help others who are like me trying to do this.

I wanted to build an application that allowed users to connect to thier webcam show a preview of what they are doing in a PictureBox and then allow the user to save a capture of that video to file.

Only problem was.... the file was too big.

I needed to access this information and pass it to the internet so I needed the files to be smaller, instead of AVI i needed WMV. So i researched codecs and Encoding and came up with a solution using a code i found for a screengrab program. The filesize was WMV and that was perfect.

Only problem was.... it captured and encoded the screengrab, and not the webcam

So i did some more research and basically tried to combine the two codes, I did, i managed to clean up the two codes so they were reading properly one was pointing to the picturebox with a preview and the other was making a file that was a WMV, YES!!!... only... not...

Since i set the code up as two different controls for one device... .now i can call the Webcam to the picture window to preview it.... but i cannot capture with the saveas function, because the preview control is still using the webcam...... SOOOOO.... after all of that i ask for your help. Can someone look at this code and see where i went wrong. Im thinking that i need to call the same "Source" to the PictureBox as the capture, but im not sure.

Here is my code, any help is more than appreciated.

Imports WMEncoderLib
Imports WMPREVIEWLib
Imports System.IO
Imports System.Runtime.InteropServices
 
 
 
Public Class Form1
 
    Inherits System.Windows.Forms.Form
 
    Dim Encoder As WMEncoder
 
    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
        'load listbox
 
        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
 
        btnStart.Enabled = True
        btnSave.Enabled = False
        picCapture.SizeMode = PictureBoxSizeMode.StretchImage
 
 
        ' Create a WMEncoder object.
 
        Encoder = New WMEncoder
        ' Retrieve the source group collection and add a source group. 
 
        Dim SrcGrp As IWMEncSourceGroup2
        Dim SrcGrpColl As IWMEncSourceGroupCollection
        SrcGrpColl = Encoder.SourceGroupCollection
        SrcGrp = SrcGrpColl.Add("SG_1")
 
        ' Add a video and audio source to the source group.
        Dim SrcVid As IWMEncVideoSource2
        Dim SrcAud As IWMEncAudioSource
        SrcVid = SrcGrp.AddSource(WMENC_SOURCE_TYPE.WMENC_VIDEO)
        SrcAud = SrcGrp.AddSource(WMENC_SOURCE_TYPE.WMENC_AUDIO)
 
        ' Identify the source files to encode.
        SrcVid.SetInput("Default_Video_Device", "Device", "")
        SrcAud.SetInput("Device://Default_Audio_Device")
 
        ' Choose a profile from the collection.
        Dim ProColl As IWMEncProfileCollection
        Dim Pro As IWMEncProfile
        Dim i As Integer
        Dim lLength As Long
 
        ProColl = Encoder.ProfileCollection
        lLength = ProColl.Count
        'For i = 0 To lLength - 1
        '    Console.WriteLine(ProColl.Item(i).Name)
        'Next
        For i = 0 To lLength - 1
            Pro = ProColl.Item(i)
            If Pro.Name = "Windows Media Video 8 for Local Area Network (384 Kbps)" Then
                SrcGrp.Profile = Pro
                Exit For
            End If
        Next
 
        ' Fill in the description object members.
        Dim Descr As IWMEncDisplayInfo
        Descr = Encoder.DisplayInfo
        Descr.Author = "Armoghan Asif"
        Descr.Copyright = "Copyright information"
        Descr.Description = "Text description of encoded content"
        Descr.Rating = "Rating information"
        Descr.Title = "Title of encoded content"
 
        ' Add an attribute to the collection.
        Dim Attr As IWMEncAttributes
        Attr = Encoder.Attributes
        Attr.Add("URL", "www.EpicRI.com")
 
        ' Specify a file object in which to save encoded content.
        Dim File As IWMEncFile
        File = Encoder.File
        File.LocalFileName = "C:\OutputFile.wmv"
 
        ' Crop 2 pixels from each edge of the video image.
        SrcVid.CroppingBottomMargin = 2
        SrcVid.CroppingTopMargin = 2
        SrcVid.CroppingLeftMargin = 2
        SrcVid.CroppingRightMargin = 2
 
    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, picCapture.Width, picCapture.Height, _
                    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 Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnStopRecord.Click
        If Encoder.RunState Then
            Encoder.Stop()
        End If
    End Sub
 
    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnStartRecord.Click
 
        ' Start the encoding process.
        Encoder.Start()
 
    End Sub
 
    Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnClose.Click
        Close()
    End Sub
 
    Private Sub btnStopCamera_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