VintaSoft Twain .NET SDK 15.3: Documentation for .NET developer
In This Topic
    Acquire images from SANE image scanner synchronously
    In This Topic
    VintaSoft Twain .NET SDK allows to acquire images from SANE image scanner synchronously (in a modal loop).

    Here are steps, which should be done for synchronous acquisition of images from SANE device:
    1. Open SANE device manager.
    2. Open SANE device.
    3. Set the scanning settings.
    4. Start the acquisition modal loop.
    5. Start the synchronous acquisition of images from eSCL device by calling SaneLocalDevice.AcquireImageSync method.
    6. Break loop if SaneLocalDevice.HasMoreImagesToScan property returns true.

    Here is an example that demonstrates how to synchronously acquire images from SANE device and save acquired images to a PDF document:
    /// <summary>
    /// Synchronously acquire images from SANE device.
    /// </summary>
    public void SynchronouslyAcquireImagesFromSaneDevice()
    {
        // create SANE device manager
        using (Vintasoft.Sane.SaneLocalDeviceManager deviceManager = new Vintasoft.Sane.SaneLocalDeviceManager())
        {
            // open SANE device manager
            deviceManager.Open();
    
            // get count of SANE devices
            int deviceCount = deviceManager.Devices.Count;
            if (deviceCount == 0)
            {
                System.Console.WriteLine("Devices are not found.");
                return;
            }
    
            // select the first SANE device
            Vintasoft.Sane.SaneLocalDevice device = deviceManager.Devices[0];
    
            // open SANE device
            device.Open();
    
            int imageIndex = 0;
            Vintasoft.Sane.SaneAcquiredImage acquiredImage;
            do
            {
                try
                {
                    // acquire image from SANE device
                    acquiredImage = device.AcquireImageSync();
                    // if image is received
                    if (acquiredImage != null)
                    {
                        imageIndex++;
                        string filename = string.Format("scannedImage-{0}.png", imageIndex);
                        if (System.IO.File.Exists(filename))
                            System.IO.File.Delete(filename);
    
                        acquiredImage.Save(filename);
    
                        System.Console.WriteLine(string.Format("Acquired image is saved to a file '{0}'.", filename));
                    }
                    // if image is not received
                    else
                    {
                        System.Console.WriteLine("Scan is completed.");
                        break;
                    }
                }
                catch (System.Exception ex)
                {
                    System.Console.WriteLine(string.Format("Scan is failed: {0}", ex.Message));
                    break;
                }
            }
            // while device has more images to scan
            while (device.HasMoreImagesToScan);
    
            // close SANE device
            device.Close();
    
            // close SANE device manager
            deviceManager.Close();
        }
    
        System.Console.ReadLine();
    }
    
    ''' <summary>
    ''' Synchronously acquire images from SANE device.
    ''' </summary>
    Public Sub SynchronouslyAcquireImagesFromSaneDevice()
        ' create SANE device manager
        Using deviceManager As New Vintasoft.Sane.SaneLocalDeviceManager()
            ' open SANE device manager
            deviceManager.Open()
    
            ' get count of SANE devices
            Dim deviceCount As Integer = deviceManager.Devices.Count
            If deviceCount = 0 Then
                System.Console.WriteLine("Devices are not found.")
                Return
            End If
    
            ' select the first SANE device
            Dim device As Vintasoft.Sane.SaneLocalDevice = deviceManager.Devices(0)
    
            ' open SANE device
            device.Open()
    
            Dim imageIndex As Integer = 0
            Dim acquiredImage As Vintasoft.Sane.SaneAcquiredImage
            Do
                Try
                    ' acquire image from SANE device
                    acquiredImage = device.AcquireImageSync()
                    ' if image is received
                    If acquiredImage IsNot Nothing Then
                        imageIndex += 1
                        Dim filename As String = String.Format("scannedImage-{0}.png", imageIndex)
                        If System.IO.File.Exists(filename) Then
                            System.IO.File.Delete(filename)
                        End If
    
                        acquiredImage.Save(filename)
    
                        System.Console.WriteLine(String.Format("Acquired image is saved to a file '{0}'.", filename))
                    Else
                        ' if image is not received
                        System.Console.WriteLine("Scan is completed.")
                        Exit Try
                    End If
                Catch ex As System.Exception
                    System.Console.WriteLine(String.Format("Scan is failed: {0}", ex.Message))
                    Exit Try
                End Try
                ' while device has more images to scan
            Loop While device.HasMoreImagesToScan
    
            ' close SANE device
            device.Close()
    
            ' close SANE device manager
            deviceManager.Close()
        End Using
    
        System.Console.ReadLine()
    End Sub