VintaSoft Twain .NET SDK 15.3: Documentation for .NET developer
Vintasoft.WiaImageScanning Namespace / WiaDevice Class / AcquireImageSyncAsFileStream(WiaImageFileFormat) Method
Syntax Exceptions Remarks Example Requirements SeeAlso
In This Topic
    AcquireImageSyncAsFileStream(WiaImageFileFormat) Method (WiaDevice)
    In This Topic
    Synchronously acquires one image as byte array from this WIA device.
    Syntax
    'Declaration
    
    Public Function AcquireImageSyncAsFileStream( _
    ByVal imageFileFormat
    The format of image file that should be returned by this WIA device.
    If WIA device does not support specified image file format, WIA device will create image file in the device default image file format - in most cases in BMP format.
    As WiaImageFileFormat _
    ) As Byte[]
    public byte[] AcquireImageSyncAsFileStream(
    WiaImageFileFormat imageFileFormat
    )
    public: byte[] AcquireImageSyncAsFileStream(
    WiaImageFileFormat imageFileFormat
    )
    public:
    byte[] AcquireImageSyncAsFileStream(
    WiaImageFileFormat imageFileFormat
    )

    Parameters

    imageFileFormat
    The format of image file that should be returned by this WIA device.
    If WIA device does not support specified image file format, WIA device will create image file in the device default image file format - in most cases in BMP format.

    Return Value

    A byte array that contains data of image file.
    Exceptions
    ExceptionDescription
    Thrown if device is not opened OR document feeder is empty OR scan is failed.
    Remarks

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

    Example

    This C#/VB.NET code shows how to synchronously acquire images as JPEG stream from WIA device.

    
    ''' <summary>
    ''' Synchronously acquire images as JPEG stream from WIA image scanner.
    ''' </summary>
    Public Sub SynchronouslyAcquireImagesAsJpegStreamFromWiaDevice()
        ' create WIA device manager
        Using deviceManager As New Vintasoft.WiaImageScanning.WiaDeviceManager()
            ' open WIA device manager
            deviceManager.Open()
    
            ' get count of WIA 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 WIA device
            Dim device As Vintasoft.WiaImageScanning.WiaDevice = deviceManager.Devices(0)
    
            ' open WIA device
            device.Open()
    
            Dim imageIndex As Integer = 0
            Dim acquiredImageBytes As Byte() = Nothing
            Do
                Try
                    ' acquire image as JPEG stream from WIA device
                    acquiredImageBytes = device.AcquireImageSyncAsFileStream(Vintasoft.WiaImageScanning.WiaImageFileFormat.JPEG)
                    ' if image is received
                    If acquiredImageBytes IsNot Nothing Then
                        imageIndex += 1
                        Dim filename As String = String.Format("scannedImage-{0}.jpg", imageIndex)
                        If System.IO.File.Exists(filename) Then
                            System.IO.File.Delete(filename)
                        End If
    
                        System.IO.File.WriteAllBytes(filename, acquiredImageBytes)
    
                        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 acquiredImageBytes IsNot Nothing
    
            ' close WIA device
            device.Close()
    
            ' close WIA device manager
            deviceManager.Close()
        End Using
    
        System.Console.ReadLine()
    End Sub
    
    
    
    /// <summary>
    /// Synchronously acquire images as JPEG stream from WIA image scanner.
    /// </summary>
    public void SynchronouslyAcquireImagesAsJpegStreamFromWiaDevice()
    {
        // create WIA device manager
        using (Vintasoft.WiaImageScanning.WiaDeviceManager deviceManager = new Vintasoft.WiaImageScanning.WiaDeviceManager())
        {
            // open WIA device manager
            deviceManager.Open();
    
            // get count of WIA devices
            int deviceCount = deviceManager.Devices.Count;
            if (deviceCount == 0)
            {
                System.Console.WriteLine("Devices are not found.");
                return;
            }
    
            // select the first WIA device
            Vintasoft.WiaImageScanning.WiaDevice device = deviceManager.Devices[0];
    
            // open WIA device
            device.Open();
    
            int imageIndex = 0;
            byte[] acquiredImageBytes = null;
            do
            {
                try
                {
                    // acquire image as JPEG stream from WIA device
                    acquiredImageBytes = device.AcquireImageSyncAsFileStream(Vintasoft.WiaImageScanning.WiaImageFileFormat.JPEG);
                    // if image is received
                    if (acquiredImageBytes != null)
                    {
                        imageIndex++;
                        string filename = string.Format("scannedImage-{0}.jpg", imageIndex);
                        if (System.IO.File.Exists(filename))
                            System.IO.File.Delete(filename);
    
                        System.IO.File.WriteAllBytes(filename, acquiredImageBytes);
    
                        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 (acquiredImageBytes != null);
    
            // close WIA device
            device.Close();
    
            // close WIA device manager
            deviceManager.Close();
        }
    
        System.Console.ReadLine();
    }
    
    

    Requirements

    Target Platforms: .NET 10; .NET 9; .NET 8; .NET 7; .NET 6; .NET Framework 4.8, 4.7, 4.6, 4.5, 4.0, 3.5

    See Also