/// <summary>
/// Reads barcodes from a multipage TIFF file.
/// </summary>
/// <param name="filename">A path to a multipage TIFF file.</param>
/// <param name="barcodeType">A type of barcodes, which must be recognized.</param>
public static void ReadBarcodesFromMiltipageTiffFile(string filename, Vintasoft.Barcode.BarcodeType barcodeType)
{
    // open TIFF file
    using (System.Drawing.Image tiffImage = System.Drawing.Image.FromFile(filename))
    {
        System.Guid index = tiffImage.FrameDimensionsList[0];
        System.Drawing.Imaging.FrameDimension dimension = new System.Drawing.Imaging.FrameDimension(index);
        int pageCount = tiffImage.GetFrameCount(dimension);

        // create the barcode reader
        using (Vintasoft.Barcode.BarcodeReader reader = new Vintasoft.Barcode.BarcodeReader())
        {
            // set barcode reader settings
            reader.Settings.ScanBarcodeTypes = barcodeType;

            // read barcodes from all pages
            for (int i = 0; i < pageCount; i++)
            {
                // select a page
                tiffImage.SelectActiveFrame(dimension, i);

                // read barcodes
                Vintasoft.Barcode.IBarcodeInfo[] barcodesInfo = Vintasoft.Barcode.GdiExtensions.ReadBarcodes(reader, tiffImage);

                // output information about barcodes
                System.Console.WriteLine(string.Format("Page {0}: ", i));
                // if barcodes are not detected
                if (barcodesInfo.Length == 0)
                {
                    System.Console.WriteLine("No barcodes found.");
                }
                // if barcodes are detected
                else
                {
                    // get information about extracted barcodes

                    for (int j = 0; j < barcodesInfo.Length; j++)
                        System.Console.WriteLine(string.Format("[{0}] {1}", barcodesInfo[j].BarcodeType,
                                                                     barcodesInfo[j].Value));
                }
            }
        }
    }
}       

''' <summary>
''' Reads barcodes from a multipage TIFF file.
''' </summary>
''' <param name="filename">A path to a multipage TIFF file.</param>
''' <param name="barcodeType">A type of barcodes, which must be recognized.</param>
Public Shared Sub ReadBarcodesFromMiltipageTiffFile(filename As String, barcodeType As Vintasoft.Barcode.BarcodeType)
    ' open TIFF file
    Using tiffImage As System.Drawing.Image = System.Drawing.Image.FromFile(filename)
        Dim index As System.Guid = tiffImage.FrameDimensionsList(0)
        Dim dimension As New System.Drawing.Imaging.FrameDimension(index)
        Dim pageCount As Integer = tiffImage.GetFrameCount(dimension)

        ' create the barcode reader
        Using reader As New Vintasoft.Barcode.BarcodeReader()
            ' set barcode reader settings
            reader.Settings.ScanBarcodeTypes = barcodeType

            ' read barcodes from all pages
            For i As Integer = 0 To pageCount - 1
                ' select a page
                tiffImage.SelectActiveFrame(dimension, i)

                ' read barcodes
                Dim barcodesInfo As Vintasoft.Barcode.IBarcodeInfo() = Vintasoft.Barcode.GdiExtensions.ReadBarcodes(reader, tiffImage)

                ' output information about barcodes
                System.Console.WriteLine(String.Format("Page {0}: ", i))
                ' if barcodes are not detected
                If barcodesInfo.Length = 0 Then
                    System.Console.WriteLine("No barcodes found.")
                Else
                    ' if barcodes are detected
                    ' get information about extracted barcodes

                    For j As Integer = 0 To barcodesInfo.Length - 1
                        System.Console.WriteLine(String.Format("[{0}] {1}", barcodesInfo(j).BarcodeType, barcodesInfo(j).Value))
                    Next
                End If
            Next
        End Using
    End Using
End Sub