VintaSoft Twain .NET SDK 15.0: 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