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();
    }
}