VintaSoft Twain .NET SDK 15.2: Documentation for .NET developer
Vintasoft.EsclImageScanning Namespace / EsclDevice Class / AcquireImageSync() Method
Syntax Exceptions Remarks Example Requirements SeeAlso
In This Topic
    AcquireImageSync() Method (EsclDevice)
    In This Topic
    Synchronously acquires one image in raw format from this eSCL device.
    Syntax
    'Declaration
    
    Public Function AcquireImageSync() As EsclAcquiredImage
    
    
    public EsclAcquiredImage AcquireImageSync()
    
    
    public: EsclAcquiredImage* AcquireImageSync()
    
    
    public:
    EsclAcquiredImage^ AcquireImageSync()

    Return Value

    Current state of the image acquisition process.
    Exceptions
    ExceptionDescription
    Thrown if device is not opened OR current scanning job is not found OR device cannot return image in raw format.
    Remarks

    This method must be called in a loop until method will not return null, i.e. there is no more images to scan.

    If eSCL device supports EsclScanDocumentFormat.OctetStream format, this method will do the following steps:

    • get image data in EsclScanDocumentFormat.OctetStream format
    • create EsclAcquiredImage object from raw image data

    If eSCL device does not support EsclScanDocumentFormat.OctetStream format, this method will do the following steps:
    • get image data in EsclScanDocumentFormat.JPEG format - eSCL specification specifies that anyeSCL device must support JPEG format
    • decompress image data from JPEG format into raw format
    • create EsclAcquiredImage object from raw image data

    Example

    This C#/VB.NET code shows how to synchronously acquire images from eSCL device.

    
    ''' <summary>
    ''' Synchronously acquire images from eSCL device.
    ''' </summary>
    Public Sub SynchronouslyAcquireImagesFromEsclDevice()
        ' create eSCL device manager
        Using deviceManager As New Vintasoft.EsclImageScanning.EsclDeviceManager()
            ' open eSCL device manager
            deviceManager.Open()
    
            ' wait while the eSCL device manager searches for eSCL devices
            System.Threading.Thread.Sleep(deviceManager.DeviceSearchTimeout)
            ' 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()
    
            Dim imageIndex As Integer = 0
            Dim acquiredImage As Vintasoft.EsclImageScanning.EsclAcquiredImage = Nothing
            Do
                Try
                    ' acquire image from eSCL 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 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
    
    
    
    /// <summary>
    /// Synchronously acquire images from eSCL device.
    /// </summary>
    public void SynchronouslyAcquireImagesFromEsclDevice()
    {
        // create eSCL device manager
        using (Vintasoft.EsclImageScanning.EsclDeviceManager deviceManager = new Vintasoft.EsclImageScanning.EsclDeviceManager())
        {
            // open eSCL device manager
            deviceManager.Open();
    
            // wait while the eSCL device manager searches for eSCL devices
            System.Threading.Thread.Sleep(deviceManager.DeviceSearchTimeout);
            // 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();
    
            int imageIndex = 0;
            Vintasoft.EsclImageScanning.EsclAcquiredImage acquiredImage = null;
            do
            {
                try
                {
                    // acquire image from eSCL 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 image is acquired
            while (acquiredImage != null);
    
            // close eSCL device
            device.Close();
    
            // close eSCL device manager
            deviceManager.Close();
        }
    
        System.Console.ReadLine();
    }
    
    

    Requirements

    Target Platforms: .NET 9; .NET 8; .NET 7; .NET 6; .NET Framework 4.8, 4.7, 4.6, 4.5

    See Also