VintaSoft Twain .NET SDK 15.5: 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
)

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 11; .NET 10; .NET 9; .NET 8; .NET 6; .NET Framework 4.8, 4.7, 4.6, 4.5, 4.0, 3.5

See Also