GdPictureImaging.TwainAcquireToGdPictureImage Method

Acquires a single image, from the currently selected Data Source.

public int TwainAcquireToGdPictureImage(
    IntPtr HANDLE
);

Visual Basic

Public Function TwainAcquireToGdPictureImage(
    ByVal HANDLE As IntPtr
) As Integer

Parameters

Parameters	Description
HANDLE	A Window Handle IE: Me.Handle. In most applications you can use nothing but on Citrix and WTS, this must be a top-level window or a child of a top level window.

Returns

0: The image could not created. Use the GetStat(), TwainGetLastResultCode() and TwainGetLastConditionCode() functions for diagnosing the error.

Non-zero: GdPicture Image Identifier. The created image.

Remarks

If success, set the created GdPicture Image as a GdPicture image.

By default, the default data source (DS) is opened, displays its dialog, and determines all the parameters of the acquisition and transfer.

If you want to (try to) hide the DS dialog, see TwainSetHideUI.

Before using this function check that the TWAIN state is >= 4 (TWAIN_SOURCE_OPEN)

To get the TWAIN state, use the TwainGetState() function.

To set the TWAIN state to 4, use the TwainOpenDefaultSource() or TwainOpenSource() function.

Example

Acquire multiple image from the document feeder to a multipage tiff image

Copy Code

Dim oGdPictureImaging As New GdPictureImaging
Dim ImageID As Integer
Dim bContinue As Boolean = True
Dim MultipageHandle As Integer
Dim ImageCount As Integer
 
oGdPictureImaging.SetLicenseNumber("XXX") 'Replace XXX by a demo or commercial license key
 
oGdPictureImaging.TwainOpenDefaultSource(Me.Handle)
oGdPictureImaging.TwainSetAutoFeed(True) 'Enable AutoFeed
oGdPictureImaging.TwainSetAutoScan(True) 'To  achieve the maximum scanning rate
oGdPictureImaging.TwainSetPixelType(TwainPixelType.TWPT_BW) '1 bit bw image
oGdPictureImaging.TwainEnableDuplex(True) 'Duplex acquisition if supported
oGdPictureImaging.TwainSetHideUI(True) 'Asks to the device to hide his GUI
 
ImageCount = 0
Do
    ImageID = oGdPictureImaging.TwainAcquireToGdPictureImage(Me.Handle)
    If ImageID <> 0 Then
        ImageCount = ImageCount + 1
        If ImageCount = 1 Then
            MultipageHandle = ImageID
            oGdPictureImaging.TiffSaveAsMultiPageFile(MultipageHandle, "multipage.tif", TiffCompression.TiffCompressionAUTO)
        Else
            oGdPictureImaging.TiffAddToMultiPageFile(MultipageHandle, ImageID)
            oGdPictureImaging.ReleaseGdPictureImage(ImageID)
        End If
    End If
Loop While oGdPictureImaging.TwainGetState() > TwainStatus.TWAIN_SOURCE_ENABLED
oGdPictureImaging.ReleaseGdPictureImage(MultipageHandle)
oGdPictureImaging.TwainCloseSource()