Public Enum IccProfile As Integer
    Gray = 1
    RGB = 3
    CMYK = 4
End Enum

Public Sub AttachIccProfile(ByVal IccProfile As IccProfile, ByRef Document As PdfDocument)
    If Document Is Nothing Then Throw New ArgumentNullException("Document")

    Dim ProfilePath As String = ""

    Select Case IccProfile
        Case IccProfile.Gray
            ProfilePath = "grayscale.icc"
        Case IccProfile.RGB
            ProfilePath = "rgb.icc"
        Case IccProfile.CMYK
            ProfilePath = "cmyk.icc"
        Case Else
            Throw New ArgumentOutOfRangeException("IccProfile")
    End Select

    Dim IccArray As New PdfArray(Document)
    Dim IccDict As New PdfDictionary(Document)
    Dim FilterArray As New PdfArray(Document)

    FilterArray.Elements.Add(New PdfName("/FlateDecode"))

    Using EncodedIcc As New MemoryStream()
        Using ds As New DeflateStream(ipstream, CompressionMode.Compress, True)
            Using fs As New FileStream(ProfilePath, FileMode.Open, FileAccess.Read)
                Dim Buffer(CInt(fs.Length - 1)) As Byte, Size As Integer = 0
                Size = fs.Read(Buffer, 0, Buffer.Length)
                ds.Write(Buffer, 0, Size)
            End Using
        End Using

        IccDict.Elements("/N") = New PdfInteger(CInt(IccProfile))
        IccDict.Elements("/Filter") = FilterArray
        IccDict.Stream = IccDict.CreateStream(EncodedIcc.GetBuffer())
    End Using

    Document.Internals.AddObject(IccDict)

    IccArray.Elements.Add(New PdfName("/ICCBased"))
    IccArray.Elements.Add(PdfInternals.GetReference(IccDict))

    Document.Internals.AddObject(IccArray)
End Sub

10 0 obj          % Color space
    [/ICCBased  15 0 R]
endobj

15 0 obj          % ICC profile stream
    <<  /N  3
        /Alternate  /DeviceRGB
        /Length  1605
        /Filter  /ASCIIHexDecode
    >>
stream
[stream data here...]
endstream
endobj