Knowledge Base :: Why do I only get the first image into Dynamic Web TWAIN although multiple documents have been scanned through ADF?

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Why do I only get the first image into Dynamic Web TWAIN although multiple documents have been scanned through ADF?

Symptom:

You may find only the first image is held in buffer after you scan multiple images by using ADF.

Cause:

The source is closed after the first transfer ends.

Resolution:

You can follow the steps below to solve the problem:

1. Please check if the CloseSource method or the CloseSourceManage method is called in the OnPostTransfer event. If yes, please comment it out.

2. Use the IfDisableSourceAfterAcquire property before the AcquireImage method or use the DisableSource method in the OnPostTransfer event to disable the source.
Click here for more information about the difference between "close source" and "disable soure" (TWAIN state transition).

Code:

function btnScan_onclick()
{
   frmScan.DynamicWebTwain1.SelectSource();
   frmScan.DynamicWebTwain1.OpenSource();
   frmScan.DynamicWebTwain1.MaxImagesInBuffer = 4;

   frmScan.DynamicWebTwain1.IfDisableSourceAfterAcquire = true;
   //disable data source

   frmScan.DynamicWebTwain1.AcquireImage();
}

Reference:

CloseSource IfDisableSourceAfterAcquire DisableSource