Public Sub AcquireImagesUsingFileTransferModeAsJpegFiles()
        Using deviceManager As New Vintasoft.Twain.DeviceManager()
                ' open the device manager
                deviceManager.Open()

                ' get reference to the default device
                Dim device As Vintasoft.Twain.Device = deviceManager.DefaultDevice

                device.ShowUI = False
                device.DisableAfterAcquire = True

                ' open the device
                device.Open()

                ' set acquisition parameters
                device.TransferMode = Vintasoft.Twain.TransferMode.File
                device.FileFormat = Vintasoft.Twain.TwainImageFileFormat.Jpeg
                device.FileJpegQuality = 70

                Dim imageCount As Integer = 0
                ' set filename the first acquired image
                device.FileName = String.Format("c:\images\page{0}.jpg", System.Math.Max(System.Threading.Interlocked.Increment(imageCount),imageCount - 1))

                ' acquire images from device
                Dim acquireModalState As Vintasoft.Twain.AcquireModalState = Vintasoft.Twain.AcquireModalState.None
                Do
                        acquireModalState = device.AcquireModal()
                        Select Case acquireModalState
                                Case Vintasoft.Twain.AcquireModalState.ImageAcquired
                                        ' set filename for next acquired image
                                        device.FileName = String.Format("c:\images\page{0}.jpg", System.Math.Max(System.Threading.Interlocked.Increment(imageCount),imageCount - 1))
                                        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

public void AcquireImagesUsingFileTransferModeAsJpegFiles()
{
    using (Vintasoft.Twain.DeviceManager deviceManager = new Vintasoft.Twain.DeviceManager())
    {
        // open the device manager
        deviceManager.Open();

        // get reference to the default device
        Vintasoft.Twain.Device device = deviceManager.DefaultDevice;

        device.ShowUI = false;
        device.DisableAfterAcquire = true;

        // open the device
        device.Open();

        // set acquisition parameters
        device.TransferMode = Vintasoft.Twain.TransferMode.File;
        device.FileFormat = Vintasoft.Twain.TwainImageFileFormat.Jpeg;
        device.FileJpegQuality = 70;

        int imageCount = 0;
        // set filename the first acquired image
        device.FileName = string.Format(@"c:\images\page{0}.jpg", imageCount++);

        // acquire images from device
        Vintasoft.Twain.AcquireModalState acquireModalState = Vintasoft.Twain.AcquireModalState.None;
        do
        {
            acquireModalState = device.AcquireModal();
            switch (acquireModalState)
            {
                case Vintasoft.Twain.AcquireModalState.ImageAcquired:
                    // set filename for next acquired image
                    device.FileName = string.Format(@"c:\images\page{0}.jpg", imageCount++);
                    break;
            }
        }
        while (acquireModalState != Vintasoft.Twain.AcquireModalState.None);

        // close the device
        device.Close();

        // close the device manager
        deviceManager.Close();
    }
}