Can someone check the code for fetching the message back ?

Module SteganoHelper
    Public Function embed(ByVal workImg As Bitmap, ByVal plainText As String) As Bitmap

        Dim rect As New Rectangle(0, 0, workImg.Width, workImg.Height)
        Dim workImgData As System.Drawing.Imaging.BitmapData
        workImgData = workImg.LockBits(rect, Imaging.ImageLockMode.ReadWrite, workImg.PixelFormat)
        'rect = Nothing

        Dim ptr As IntPtr
        ptr = workImgData.Scan0
        Dim tempsize As Integer
        tempsize = Math.Abs(workImgData.Stride * workImg.Height)
        Dim bitMapData As Byte()
        ReDim bitMapData(tempsize)
        System.Runtime.InteropServices.Marshal.Copy(ptr, bitMapData, 0, bitMapData.Length)
        'Dim R, G, B, A As Byte
        Dim bitindex As Integer
        ' bitindex = 65
        bitindex = 0
      

        For Each c As Char In plainText             'iterating through each character from the text
            Dim x, y As Byte
            x = AscW(c)
            'converting the character to Byte
            Dim i As Integer
            i = 7
            For i = 7 To 0 Step -1
                y = x >> i                                      'Read individual bits from character right to left
                y = y Mod 2
                ' y = x Mod 2
                ' x = x / 2
                'by shifting the required bits to rightmost position and then getting the first digit

                Dim bit As Integer
                bit = bitMapData(bitindex)

                bitMapData(bitindex) = bitMapData(bitindex) - (bitMapData(bitindex) Mod 2)  'LSB of pixel set to 0..
                bitMapData(bitindex) = bitMapData(bitindex) + y   ' one bit of character added to the color component

                bit = bitMapData(bitindex)
                If (((bitindex + 2) Mod 4) = 0) Then
                    bitindex = bitindex + 2                         'ignore every 4th value in case the image supports transparent component RGB'A'RGB'A'RGB'A' 
                Else
                    bitindex = bitindex + 1
                End If
                'bitindex = bitindex + 1
            Next
        Next
        For i = 0 To 7 Step +1                                       'Adding a termination character
            bitMapData(bitindex) = bitMapData(bitindex) - bitMapData(bitindex) Mod 2   'LSB of pixel set to 0

            If (((bitindex + 2) Mod 4) = 0) Then
                bitindex = bitindex + 2
            Else
                bitindex = bitindex + 1
            End If
            ' bitindex = bitindex + 1
            i = i + 1
        Next
        System.Runtime.InteropServices.Marshal.Copy(bitMapData, 0, ptr, bitMapData.Length)

        workImg.UnlockBits(workImgData)
        Return workImg

    End Function
    Public Function disEmbed(ByVal workImg As Bitmap) As String
        Dim PlainText As String
        PlainText = ""
        Dim bitindex As Integer
        bitindex = 0
        Dim rect As New Rectangle(0, 0, workImg.Width, workImg.Height)
        Dim workImgData As System.Drawing.Imaging.BitmapData
        workImgData = workImg.LockBits(rect, Imaging.ImageLockMode.ReadWrite, workImg.PixelFormat)
        'rect = Nothing

        Dim ptr As IntPtr
        ptr = workImgData.Scan0
        Dim tempsize As Integer
        tempsize = Math.Abs(workImgData.Stride * workImg.Height)
        Dim bitMapData As Byte()
        ReDim bitMapData(tempsize)
        System.Runtime.InteropServices.Marshal.Copy(ptr, bitMapData, 0, bitMapData.Length)
        Dim charvalue As Integer

        While vbTrue
            charvalue = 0
            For i = 0 To 7 Step +1
                charvalue = charvalue * 2 + bitMapData(bitindex) Mod 2
                
                If (((bitindex + 2) Mod 4) = 0) Then
                    bitindex = bitindex + 2
                Else
                    bitindex = bitindex + 1
                End If
                'bitindex = bitindex + 1
            Next
            If charvalue = 0 Then
                Return PlainText
            End If
            charvalue = reverseBits(charvalue)
            Dim c As Char
           
            c = Convert.ToChar(charvalue)
            ' c = Chr(charvalue)
            
            PlainText = PlainText + c
        End While

        Return PlainText
    End Function
    Public Function reverseBits(ByVal n As Integer) As Integer

        Dim result As Integer
        result = 0

        For i = 0 To 7 Step +1

            result = result * 2 + n Mod 2

            n /= 2


        Next
        Return result
    End Function
End Module