VintaSoft Twain .NET SDK 15.4: 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