''' <summary>
''' Renders a PDF document with optional content.
''' </summary>
''' <param name="pdfFilename">The PDF filename.</param>
Public Shared Sub RenderPdfUsingOptonalContent(pdfFilename As String)
    ' get name of output PDF file
    Dim outputFileName As String = System.IO.Path.Combine(System.IO.Path.GetDirectoryName(pdfFilename), System.IO.Path.GetFileNameWithoutExtension(pdfFilename))
    outputFileName = outputFileName & "_{0}_{1}.tif"

    ' open document stream
    Using documentStream As System.IO.Stream = System.IO.File.Open(pdfFilename, System.IO.FileMode.Open)
        ' create image collection, which will store pages of PDF document
        Using documentImages As New Vintasoft.Imaging.ImageCollection()
            ' add document pages to the image collection
            documentImages.Add(documentStream)

            ' open PDF document
            Dim document As Vintasoft.Imaging.Pdf.PdfDocument = Vintasoft.Imaging.Pdf.PdfDocumentController.OpenDocument(documentStream)

            ' if document does not have optional content
            If document.OptionalContentProperties Is Nothing Then
                System.Console.WriteLine("Document does not have optional content.")
                Return
            End If

            ' if PDF document has the default optional content configuration
            If document.OptionalContentProperties.DefaultConfiguration IsNot Nothing Then
                ' set the default optional content configuration as current optional content configuration
                document.OptionalContentConfiguration = document.OptionalContentProperties.DefaultConfiguration
                ' render PDF pages and save them to a multipage TIFF file
                SaveImages(documentImages, String.Format(outputFileName, "defaultConfig", document.OptionalContentConfiguration.Name))
            End If

            ' if PDF document has a list of optional content configurations
            If document.OptionalContentProperties.Configurations IsNot Nothing Then
                ' for each optional content configuration
                For Each config As Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentConfiguration In document.OptionalContentProperties.Configurations
                    ' set the optional content configuration as current optional content configuration
                    document.OptionalContentConfiguration = config
                    ' render PDF pages and save them to a multipage TIFF file
                    SaveImages(documentImages, String.Format(outputFileName, "config", config.Name))
                Next
            End If


            ' create custom optional content configuration
            Dim myConfig As New Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentConfiguration(document, "MyConfig")
            ' create an empty list of optional content groups whose state should
            ' be set to ON when this configuration is applied
            myConfig.OnGroups = New Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentGroupList(document)
            ' specify that optional content groups are "Off" by default
            myConfig.BaseState = Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentConfigurationBaseState.Off
            ' set custom optional content configuration as
            ' current optional content configuration of PDF document
            document.OptionalContentConfiguration = myConfig
            ' for each optional content group of PDF document
            For Each group As Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentGroup In document.OptionalContentProperties.OptionalContentGroups
                ' clear list of "On" groups, i.e. specify that groups must be not visible
                myConfig.OnGroups.Clear()
                ' add group to the list of "On" groups, i.e. specify that group must be visible
                myConfig.OnGroups.Add(group)
                ' render PDF pages and save them to a file
                SaveImages(documentImages, String.Format(outputFileName, "group", group.Name))
            Next


            ' close PDF document
            Vintasoft.Imaging.Pdf.PdfDocumentController.CloseDocument(document)

            ' free resources
            documentImages.ClearAndDisposeItems()
        End Using
    End Using
End Sub

''' <summary>
''' Saves images (PDF pages) to the specified file.
''' </summary>
''' <param name="images">The image collection.</param>
''' <param name="filename">The filename where image collection must be saved.</param>
Private Shared Sub SaveImages(images As Vintasoft.Imaging.ImageCollection, filename As String)
    ' create encoder
    Using encoder As Vintasoft.Imaging.Codecs.Encoders.MultipageEncoderBase = Vintasoft.Imaging.Codecs.Encoders.AvailableEncoders.CreateMultipageEncoder(filename)
        ' set rendering settings
        images.SetRenderingSettings(New Vintasoft.Imaging.Codecs.Decoders.RenderingSettings(New Vintasoft.Imaging.Resolution(300, 300)))

        ' specify that image collection should not be switched to new file
        encoder.SaveAndSwitchSource = False
        ' save images to a file
        images.SaveSync(filename, encoder)
    End Using
End Sub

/// <summary>
/// Renders a PDF document with optional content.
/// </summary>
/// <param name="pdfFilename">The PDF filename.</param>
public static void RenderPdfUsingOptonalContent(string pdfFilename)
{
    // get name of output PDF file
    string outputFileName = System.IO.Path.Combine(System.IO.Path.GetDirectoryName(pdfFilename), 
        System.IO.Path.GetFileNameWithoutExtension(pdfFilename));
    outputFileName = outputFileName + "_{0}_{1}.tif";

    // open document stream
    using (System.IO.Stream documentStream = 
        System.IO.File.Open(pdfFilename, System.IO.FileMode.Open))
    {
        // create image collection, which will store pages of PDF document
        using (Vintasoft.Imaging.ImageCollection documentImages = 
            new Vintasoft.Imaging.ImageCollection())
        {
            // add document pages to the image collection
            documentImages.Add(documentStream);

            // open PDF document
            Vintasoft.Imaging.Pdf.PdfDocument document = 
                Vintasoft.Imaging.Pdf.PdfDocumentController.OpenDocument(documentStream);

            // if document does not have optional content
            if (document.OptionalContentProperties == null)
            {
                System.Console.WriteLine("Document does not have optional content.");
                return;
            }

            // if PDF document has the default optional content configuration
            if (document.OptionalContentProperties.DefaultConfiguration != null)
            {
                // set the default optional content configuration as current optional content configuration
                document.OptionalContentConfiguration = document.OptionalContentProperties.DefaultConfiguration;
                // render PDF pages and save them to a multipage TIFF file
                SaveImages(documentImages, string.Format(outputFileName, "defaultConfig", document.OptionalContentConfiguration.Name));
            }

            // if PDF document has a list of optional content configurations
            if (document.OptionalContentProperties.Configurations != null)
            {
                // for each optional content configuration
                foreach (Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentConfiguration config in
                    document.OptionalContentProperties.Configurations)
                {
                    // set the optional content configuration as current optional content configuration
                    document.OptionalContentConfiguration = config;
                    // render PDF pages and save them to a multipage TIFF file
                    SaveImages(documentImages, string.Format(outputFileName, "config", config.Name));
                }
            }


            // create custom optional content configuration
            Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentConfiguration myConfig =
                new Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentConfiguration(document, "MyConfig");
            // create an empty list of optional content groups whose state should
            // be set to ON when this configuration is applied
            myConfig.OnGroups =
                new Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentGroupList(document);
            // specify that optional content groups are "Off" by default
            myConfig.BaseState =
                Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentConfigurationBaseState.Off;
            // set custom optional content configuration as
            // current optional content configuration of PDF document
            document.OptionalContentConfiguration = myConfig;
            // for each optional content group of PDF document
            foreach (Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentGroup 
                group in document.OptionalContentProperties.OptionalContentGroups)
            {
                // clear list of "On" groups, i.e. specify that groups must be not visible
                myConfig.OnGroups.Clear();
                // add group to the list of "On" groups, i.e. specify that group must be visible
                myConfig.OnGroups.Add(group);
                // render PDF pages and save them to a file
                SaveImages(documentImages, string.Format(outputFileName, "group", group.Name));
            }


            // close PDF document
            Vintasoft.Imaging.Pdf.PdfDocumentController.CloseDocument(document);

            // free resources
            documentImages.ClearAndDisposeItems();
        }
    }
}

/// <summary>
/// Saves images (PDF pages) to the specified file.
/// </summary>
/// <param name="images">The image collection.</param>
/// <param name="filename">The filename where image collection must be saved.</param>
private static void SaveImages(Vintasoft.Imaging.ImageCollection images, string filename)
{
    // create encoder
    using (Vintasoft.Imaging.Codecs.Encoders.MultipageEncoderBase encoder = 
        Vintasoft.Imaging.Codecs.Encoders.AvailableEncoders.CreateMultipageEncoder(filename))
    {
        // set rendering settings
        images.SetRenderingSettings(new Vintasoft.Imaging.Codecs.Decoders.RenderingSettings(
            new Vintasoft.Imaging.Resolution(300, 300)));

        // specify that image collection should not be switched to new file
        encoder.SaveAndSwitchSource = false;
        // save images to a file
        images.SaveSync(filename, encoder);
    }
}