VintaSoft Twain .NET SDK 15.3: Documentation for .NET developer
In This Topic
    How to process TWAIN acquired image?
    In This Topic
    Here is an example that demonstrates how to acquire images from TWAIN device, process images and save only not blank images to a multipage TIFF file:
    /// <summary>
    /// Acquires images from TWAIN device, processes images and saves only not blank images to a multipage TIFF file.
    /// </summary>
    public static void AcquireImagesFromTwainDeviceAndProcessImages()
    {
        // create the device manager
        using (Vintasoft.Twain.DeviceManager deviceManager = new Vintasoft.Twain.DeviceManager())
        {
            // open the device manager
            deviceManager.Open();
    
            // select the device in the default device selectio ndialog
            deviceManager.ShowDefaultDeviceSelectionDialog();
    
            // get reference to the selected device
            Vintasoft.Twain.Device device = deviceManager.DefaultDevice;
    
            // specify that device UI must not be used
            device.ShowUI = false;
            // specify that device must be closed after scan
            device.DisableAfterAcquire = true;
    
            string tiffFilename = System.IO.Path.Combine(System.IO.Directory.GetCurrentDirectory(), "multipage.tif");
    
            // acquire images from device
            Vintasoft.Twain.AcquireModalState acquireModalState = Vintasoft.Twain.AcquireModalState.None;
            Vintasoft.Twain.AcquiredImage acquiredImage;
            do
            {
                acquireModalState = device.AcquireModal();
                switch (acquireModalState)
                {
                    case Vintasoft.Twain.AcquireModalState.ImageAcquired:
                        // get reference to the image acquired from device
                        acquiredImage = device.AcquiredImage;
    
                        // despeckle/deskew/detect border
                        ProcessAcquiredImage(acquiredImage);
                        // add image to multipage TIFF file if image is not blank
                        if (!acquiredImage.IsBlank(0.01f))
                            acquiredImage.Save(tiffFilename);
    
                        // dispose acquired image
                        acquiredImage.Dispose();
                        break;
                }
            }
            while (acquireModalState != Vintasoft.Twain.AcquireModalState.None);
    
            // close the device
            device.Close();
    
            // close the device manager
            deviceManager.Close();
        }
    }
    
    private static void ProcessAcquiredImage(Vintasoft.Twain.AcquiredImage acquiredImage)
    {
        System.Console.WriteLine(string.Format("Image ({0})", acquiredImage.ImageInfo));
    
        try
        {
            // subscribe to processing events
            acquiredImage.Processing += new System.EventHandler<Vintasoft.Twain.ImageProcessing.TwainAcquiredImageProcessingEventArgs>(acquiredImage_Processing);
            acquiredImage.Progress += new System.EventHandler<Vintasoft.Twain.ImageProcessing.TwainAcquiredImageProcessingProgressEventArgs>(acquiredImage_Progress);
            acquiredImage.Processed += new System.EventHandler<Vintasoft.Twain.ImageProcessing.TwainAcquiredImageProcessedEventArgs>(acquiredImage_Processed);
    
            // despeckle/deskew/detect border
            acquiredImage.Despeckle(8, 25, 30, 400);
            acquiredImage.Deskew(Vintasoft.Twain.ImageProcessing.TwainBorderColor.AutoDetect, 5, 5);
            acquiredImage.DetectBorder(5);
        }
        catch (System.Exception ex)
        {
            System.Console.WriteLine("Error: " + ex.Message);
        }
        finally
        {
            // unsubscribe from processing events
            acquiredImage.Processing -= new System.EventHandler<Vintasoft.Twain.ImageProcessing.TwainAcquiredImageProcessingEventArgs>(acquiredImage_Processing);
            acquiredImage.Progress -= new System.EventHandler<Vintasoft.Twain.ImageProcessing.TwainAcquiredImageProcessingProgressEventArgs>(acquiredImage_Progress);
            acquiredImage.Processed -= new System.EventHandler<Vintasoft.Twain.ImageProcessing.TwainAcquiredImageProcessedEventArgs>(acquiredImage_Processed);
        }
    }
    
    static void acquiredImage_Processing(object sender, Vintasoft.Twain.ImageProcessing.TwainAcquiredImageProcessingEventArgs e)
    {
        System.Console.Write(e.Action.ToString() + " ");
    }
    
    static void acquiredImage_Progress(object sender, Vintasoft.Twain.ImageProcessing.TwainAcquiredImageProcessingProgressEventArgs e)
    {
        System.Console.Write(".");
    }
    
    static void acquiredImage_Processed(object sender, Vintasoft.Twain.ImageProcessing.TwainAcquiredImageProcessedEventArgs e)
    {
        System.Console.WriteLine(" finished");
    }
    
    ''' <summary>
    ''' Acquires images from TWAIN device, processes images and saves only not blank images to a multipage TIFF file.
    ''' </summary>
    Public Shared Sub AcquireImagesFromTwainDeviceAndProcessImages()
        ' create the device manager
        Using deviceManager As New Vintasoft.Twain.DeviceManager()
            ' open the device manager
            deviceManager.Open()
    
            ' select the device in the default device selectio ndialog
            deviceManager.ShowDefaultDeviceSelectionDialog()
    
            ' get reference to the selected device
            Dim device As Vintasoft.Twain.Device = deviceManager.DefaultDevice
    
            ' specify that device UI must not be used
            device.ShowUI = False
            ' specify that device must be closed after scan
            device.DisableAfterAcquire = True
    
            Dim tiffFilename As String = System.IO.Path.Combine(System.IO.Directory.GetCurrentDirectory(), "multipage.tif")
    
            ' acquire images from device
            Dim acquireModalState As Vintasoft.Twain.AcquireModalState = Vintasoft.Twain.AcquireModalState.None
            Dim acquiredImage As Vintasoft.Twain.AcquiredImage
            Do
                acquireModalState = device.AcquireModal()
                Select Case acquireModalState
                    Case Vintasoft.Twain.AcquireModalState.ImageAcquired
                        ' get reference to the image acquired from device
                        acquiredImage = device.AcquiredImage
    
                        ' despeckle/deskew/detect border
                        ProcessAcquiredImage(acquiredImage)
                        ' add image to multipage TIFF file if image is not blank
                        If Not acquiredImage.IsBlank(0.01F) Then
                            acquiredImage.Save(tiffFilename)
                        End If
    
                        ' dispose acquired image
                        acquiredImage.Dispose()
                        Exit Select
                End Select
            Loop While acquireModalState <> Vintasoft.Twain.AcquireModalState.None
    
            ' close the device
            device.Close()
    
            ' close the device manager
            deviceManager.Close()
        End Using
    End Sub
    
    Private Shared Sub ProcessAcquiredImage(acquiredImage As Vintasoft.Twain.AcquiredImage)
        System.Console.WriteLine(String.Format("Image ({0})", acquiredImage.ImageInfo))
    
        Try
            ' subscribe to processing events
            AddHandler acquiredImage.Processing, New System.EventHandler(Of Vintasoft.Twain.ImageProcessing.TwainAcquiredImageProcessingEventArgs)(AddressOf acquiredImage_Processing)
            AddHandler acquiredImage.Progress, New System.EventHandler(Of Vintasoft.Twain.ImageProcessing.TwainAcquiredImageProcessingProgressEventArgs)(AddressOf acquiredImage_Progress)
            AddHandler acquiredImage.Processed, New System.EventHandler(Of Vintasoft.Twain.ImageProcessing.TwainAcquiredImageProcessedEventArgs)(AddressOf acquiredImage_Processed)
    
            ' despeckle/deskew/detect border
            acquiredImage.Despeckle(8, 25, 30, 400)
            acquiredImage.Deskew(Vintasoft.Twain.ImageProcessing.TwainBorderColor.AutoDetect, 5, 5)
            acquiredImage.DetectBorder(5)
        Catch ex As System.Exception
            System.Console.WriteLine("Error: " & ex.Message)
        Finally
            ' unsubscribe from processing events
            RemoveHandler acquiredImage.Processing, New System.EventHandler(Of Vintasoft.Twain.ImageProcessing.TwainAcquiredImageProcessingEventArgs)(AddressOf acquiredImage_Processing)
            RemoveHandler acquiredImage.Progress, New System.EventHandler(Of Vintasoft.Twain.ImageProcessing.TwainAcquiredImageProcessingProgressEventArgs)(AddressOf acquiredImage_Progress)
            RemoveHandler acquiredImage.Processed, New System.EventHandler(Of Vintasoft.Twain.ImageProcessing.TwainAcquiredImageProcessedEventArgs)(AddressOf acquiredImage_Processed)
        End Try
    End Sub
    
    Private Shared Sub acquiredImage_Processing(sender As Object, e As Vintasoft.Twain.ImageProcessing.TwainAcquiredImageProcessingEventArgs)
        System.Console.Write(e.Action.ToString() & " ")
    End Sub
    
    Private Shared Sub acquiredImage_Progress(sender As Object, e As Vintasoft.Twain.ImageProcessing.TwainAcquiredImageProcessingProgressEventArgs)
        System.Console.Write(".")
    End Sub
    
    Private Shared Sub acquiredImage_Processed(sender As Object, e As Vintasoft.Twain.ImageProcessing.TwainAcquiredImageProcessedEventArgs)
        System.Console.WriteLine(" finished")
    End Sub