RTF inage insertion

See more:

VB

I am using the following borrowed code to insert an image into an RTF, as that aspect of RTF seemed way beyond me

Public Sub InsertImage(ByVal _image As Image)
        Dim _rtf As New StringBuilder()
        ' Append the RTF header
        _rtf.Append(RTF_HEADER)
        ' Create the font table using the RichTextBox's current font and append
        ' it to the RTF string
        _rtf.Append(GetFontTable(Me.Font))
        ' Create the image control string and append it to the RTF string
        _rtf.Append(GetImagePrefix(_image))
        ' Create the Windows Metafile and append its bytes in HEX format
        _rtf.Append(GetRtfImage(_image))
        ' Close the RTF image control string
        _rtf.Append(RTF_IMAGE_POST)
        Me.SelectedRtf = _rtf.ToString()
    End Sub
Private Function GetImagePrefix(ByVal _image As Image) As String
        Dim _rtf As New StringBuilder()
        ' Calculate the current width of the image in (0.01)mm
        Dim picw As Integer = CType(Math.Round((_image.Width / xDpi) * HMM_PER_INCH), Integer)
        ' Calculate the current height of the image in (0.01)mm
        Dim pich As Integer = CType(Math.Round((_image.Height / yDpi) * HMM_PER_INCH), Integer)
        ' Calculate the target width of the image in twips
        Dim picwgoal As Integer = CType(Math.Round((_image.Width / xDpi) * TWIPS_PER_INCH), Integer)
        ' Calculate the target height of the image in twips
        Dim pichgoal As Integer = CType(Math.Round((_image.Height / yDpi) * TWIPS_PER_INCH), Integer)
        
        ' Append values to RTF string
        _rtf.Append("{\pict\wmetafile8")
        _rtf.Append("\picw")
        _rtf.Append(picw)
        _rtf.Append("\pich")
        _rtf.Append(pich)
        _rtf.Append("\picwgoal")
        _rtf.Append(picwgoal)
        _rtf.Append("\pichgoal")
        _rtf.Append(picw)
        _rtf.Append(" ")
        Return _rtf.ToString()
    End Function
<DllImportAttribute("gdiplus.dll")> _
    Private Shared Function GdipEmfToWmfBits(ByVal _hEmf As IntPtr, ByVal _bufferSize As UInt32, ByVal _buffer As Byte(), ByVal _mappingMode As Integer, ByVal _flags As EmfToWmfBitsFlags) As UInt32
    End Function
    ''' <summary>
    ''' Wraps the image in an Enhanced Metafile by drawing the image onto the
    ''' graphics context, then converts the Enhanced Metafile to a Windows
    ''' Metafile, and finally appends the bits of the Windows Metafile in HEX
    ''' to a string and returns the string.
    ''' </summary>
    ''' <param name="_image"></param>
    ''' <returns>
    ''' A string containing the bits of a Windows Metafile in HEX
    ''' </returns>
    Private Function GetRtfImage(ByVal _image As Image) As String
        Dim _rtf As StringBuilder = Nothing
        ' Used to store the enhanced metafile
        Dim _stream As MemoryStream = Nothing
        ' Used to create the metafile and draw the image
        Dim _graphics As Graphics = Nothing
        ' The enhanced metafile
        Dim _metaFile As Metafile = Nothing
        ' Handle to the device context used to create the metafile
        Dim _hdc As IntPtr
        Try
            _rtf = New StringBuilder()
            _stream = New MemoryStream()
            ' Get a graphics context from the RichTextBox
            Using _graphics1 As Graphics = Me.CreateGraphics()
                ' Get the device context from the graphics context
                _hdc = _graphics1.GetHdc()
                ' Create a new Enhanced Metafile from the device context
                _metaFile = New Metafile(_stream, _hdc)
                ' Release the device context
                _graphics1.ReleaseHdc(_hdc)
            End Using
            ' Get a graphics context from the Enhanced Metafile
            Using _graphics1 As Graphics = Graphics.FromImage(_metaFile)
                ' Draw the image on the Enhanced Metafile
                _graphics1.DrawImage(_image, New Rectangle(0, 0, _image.Width, _image.Height))
            End Using
            ' Get the handle of the Enhanced Metafile
            Dim _hEmf As IntPtr = _metaFile.GetHenhmetafile()
            ' A call to EmfToWmfBits with a null buffer return the size of the
            ' buffer need to store the WMF bits.  Use this to get the buffer
            ' size.
            Dim _bufferSize As UInt32 = GdipEmfToWmfBits(_hEmf, 0, Nothing, MM_ANISOTROPIC, EmfToWmfBitsFlags.EmfToWmfBitsFlagsDefault)
            ' Create an array to hold the bits
            Dim _buffer As Byte() = New Byte(CInt(_bufferSize)) {}
            ' A call to EmfToWmfBits with a valid buffer copies the bits into the
            ' buffer an returns the number of bits in the WMF.  
            Dim _convertedSize As UInt32 = GdipEmfToWmfBits(_hEmf, _bufferSize, _buffer, MM_ANISOTROPIC, EmfToWmfBitsFlags.EmfToWmfBitsFlagsDefault)
            For i As Integer = 0 To _buffer.Length - 1
                ' Append the bits to the RTF string
                _rtf.Append([String].Format("{0:X2}", _buffer(i)))
            Next
            Return _rtf.ToString()
        Finally
            If _graphics IsNot Nothing Then
                _graphics.Dispose()
            End If
            If _metaFile IsNot Nothing Then
                _metaFile.Dispose()
            End If
            If _stream IsNot Nothing Then
                _stream.Close()
            End If
        End Try
    End Function

sorry for so much code, anyway if i use that, the image is huge, here is a sample untouched image http://img339.imageshack.us/img339/7889/barcode128g4.png[^]
i tried inserting the image with wordpad and copying the picw, pich, pichgoal, and picwgoal values from the wordpad generated RTF, but then the image looked almost squeezed together. i did notice the image hex values seemed quite different, i can't simply copy as the image itself will be different each run, I am at a loss, any help is appreciated