Question

i have a program that will capture an image using webcam using this source code…
http://www.thaiio.com/prog-cgi/vbnetwebcam.html
and this is the Sub that will get the image from the clipboard and convert it to Bitmap…

Private Sub btnSave_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSave.Click
    Dim data As IDataObject
    Dim bmap As Bitmap
    '
    ' Copy image to clipboard
    '
    SendMessage(hHwnd, WM_CAP_EDIT_COPY, 0, 0)
    '
    ' 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)), Bitmap)
        picCapture.Image = bmap
        ClosePreviewWindow()
        btnSave.Enabled = False
        btnStop.Enabled = False
        btnStart.Enabled = True
        btnInfo.Enabled = False
        Trace.Assert(Not (bmap Is Nothing))
        sfdImage.Filter = ("Jpeg|*.jpg")
        If sfdImage.ShowDialog = DialogResult.OK Then
            bmap.Save(sfdImage.FileName, Imaging.ImageFormat.Jpeg)
        End If
    End If
End Sub

i get an error “Value cannot be null. Parameter name: encoder”
when trying to save it on a Memorystream, maybe because i should get the original format first. any idea on how can i do it?

Answer 1

Sorry for posting this question, i figured out the answer. thx for the help.

Dim ms As New MemoryStream()

bmap.Save(ms, Imaging.ImageFormat.Jpeg)

Dim arrImage() As Byte = ms.GetBuffer

ms.Close()