VintaSoft Twain .NET SDK 15.2: Руководство для .NET разработчика
В этом разделе
    Как получить черно-белые изображения от eSCL сканера изображений?
    В этом разделе
    Если вы хотите получить черно-белые изображения от eSCL сканера изображений, вам следует установить цветовой режим сканирования (используя свойство EsclDevice.ScanColorMode) на значение EsclScanColorMode.BlackAndWhite1.

    Не все устройства eSCL позволяют получать черно-белые изображения. Поддерживаемые цветовые режимы сканирования можно получить с помощью метода EsclDevice.GetSupportedScanColorModes.

    Вот пример, демонстрирующий, как получить черно-белые изображения от eSCL сканера изображений:
    /// <summary>
    /// Acquires black-white images from eSCL device.
    /// </summary>
    public void AcquireBlackWhiteImageFromEsclDevice()
    {
        // create eSCL device manager
        using (Vintasoft.EsclImageScanning.EsclDeviceManager deviceManager = new Vintasoft.EsclImageScanning.EsclDeviceManager())
        {
            // open eSCL device manager
            deviceManager.Open();
    
            System.DateTime startTime = System.DateTime.Now;
            // while eSCL devices are not found
            while (deviceManager.Devices.Count == 0 && System.DateTime.Now.Subtract(startTime).Microseconds < 5000)
            {
                System.Threading.Thread.Sleep(10);
            }
            // get count of eSCL devices
            int deviceCount = deviceManager.Devices.Count;
            if (deviceCount == 0)
            {
                System.Console.WriteLine("Devices are not found.");
                return;
            }
    
            // select the first eSCL device
            Vintasoft.EsclImageScanning.EsclDevice device = deviceManager.Devices[0];
    
            // open eSCL device
            device.Open();
    
    
            // get names of supported scan modes
            Vintasoft.EsclImageScanning.EsclScanColorMode[] supportedScanColorModes = device.GetSupportedScanColorModes();
            foreach (Vintasoft.EsclImageScanning.EsclScanColorMode supportedScanMode in supportedScanColorModes)
            {
                if (supportedScanMode == Vintasoft.EsclImageScanning.EsclScanColorMode.BlackAndWhite1)
                {
                    // specify that black-white images must be acquired from eSCL device
                    device.ScanColorMode = supportedScanMode;
                    break;
                }
            }
    
    
            Vintasoft.EsclImageScanning.EsclAcquiredImage acquiredImage;
            do
            {
                try
                {
                    // acquire image from eSCL device
                    acquiredImage = device.AcquireImageSync();
                    // if image is received
                    if (acquiredImage != null)
                    {
                        System.Console.WriteLine("Image is acquired.");
                    }
                    // 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 image is acquired
            while (acquiredImage != null);
    
            // close eSCL device
            device.Close();
    
            // close eSCL device manager
            deviceManager.Close();
        }
    
        System.Console.ReadLine();
    }
    
    ''' <summary>
    ''' Acquires black-white images from eSCL device.
    ''' </summary>
    Public Sub AcquireBlackWhiteImageFromEsclDevice()
        ' create eSCL device manager
        Using deviceManager As New Vintasoft.EsclImageScanning.EsclDeviceManager()
            ' open eSCL device manager
            deviceManager.Open()
    
            Dim startTime As System.DateTime = System.DateTime.Now
            ' while eSCL devices are not found
            While deviceManager.Devices.Count = 0 AndAlso System.DateTime.Now.Subtract(startTime).Microseconds < 5000
                System.Threading.Thread.Sleep(10)
            End While
            ' get count of eSCL 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 eSCL device
            Dim device As Vintasoft.EsclImageScanning.EsclDevice = deviceManager.Devices(0)
    
            ' open eSCL device
            device.Open()
    
    
            ' get names of supported scan modes
            Dim supportedScanColorModes As Vintasoft.EsclImageScanning.EsclScanColorMode() = device.GetSupportedScanColorModes()
            For Each supportedScanMode As Vintasoft.EsclImageScanning.EsclScanColorMode In supportedScanColorModes
                If supportedScanMode = Vintasoft.EsclImageScanning.EsclScanColorMode.BlackAndWhite1 Then
                    ' specify that black-white images must be acquired from eSCL device
                    device.ScanColorMode = supportedScanMode
                    Exit For
                End If
            Next
    
    
            Dim acquiredImage As Vintasoft.EsclImageScanning.EsclAcquiredImage
            Do
                Try
                    ' acquire image from eSCL device
                    acquiredImage = device.AcquireImageSync()
                    ' if image is received
                    If acquiredImage IsNot Nothing Then
                        System.Console.WriteLine("Image is acquired.")
                    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 image is acquired
            Loop While acquiredImage IsNot Nothing
    
            ' close eSCL device
            device.Close()
    
            ' close eSCL device manager
            deviceManager.Close()
        End Using
    
        System.Console.ReadLine()
    End Sub