LTwain::AcquireMulti

Summary

Acquires one or more images from a TWAIN source and stores the images in the specified file(s).

This function is available in the Document/Medical Toolkits.

Syntax

virtual L_INT LTwain::AcquireMulti(pszBaseFileName, uFlags, uTransferMode, nFormat, nBitsPerPixel, bMultiPageFile, uUserBufSize, bUsePreferredBuffer)

Parameters

L_TCHAR *pszBaseFileName

Character string containing the base name of the image file(s) in which to save the acquired data.

L_UINT uFlags

Flag that indicates whether to display the manufacturer's user interface. Possible values are:

L_UINT uTransferMode

Flag that indicates the transfer mode to use when acquiring the image(s). Possible values are:

L_INT nFormat

Output file format. Valid values depend on the transfer mode being used.

• If the uTransferMode is LTWAIN_FILE_MODE, TWAIN handles output and the valid values are confined to the TWAIN-supported file formats. See the formats listed for the uFileFormat parameter of TRANSFEROPTIONS

• If the uTransferMode is LTWAIN_BUFFER_MODE or LTWAIN_NATIVE_MODE, LEAD handles output and can be any file format LEADTOOLS supports. Refer to Formats of Output Files for valid values.

L_INT nBitsPerPixel

Resulting file's pixel depth. Note that not all bits per pixel are available to all file formats. For valid values, refer to Formats of Output Files. If nBitsPerPixel is 0, the file will be stored using the closest BitsPerPixel value supported by that format.

L_BOOL bMultiPageFile

Flag that indicates whether to save multiple images into a single multipage file, or into a series of single page files. Possible values are:

Notice that it the format does not support multipage files, then each scanned page will be saved in a separate file.

L_UINT32 uUserBufSize

Specifies a user-defined buffer size. This value will be used if uTransferMode is LTWAIN_BUFFER_MODE and the bUsePreferredBuffer parameter is FALSE. This value must be a multiple of 16.

L_BOOL bUsePreferredBuffer

Flag that indicates whether to use the user-defined buffer size or the TWAIN driver's preferred buffer size. Possible values are:

Returns

Comments

This function will acquire one or more images from a TWAIN source and store the images to the specified file(s).

Based on the scanner type, this function will determine the best/fastest scanning method to use. This method will be used when actually scanning the image(s). Before calling this function you can call LTwain::FindFastConfig to determine the best scan configuration and then pass the scan configuration information to the LTwain::AcquireMulti function. If you do not call LTwain::FindFastConfig before calling LTwain::AcquireMulti, then the LTwain::AcquireMulti function will determine the best scanning method.

If the file format specified in nFormat does not support multipage files, this function will ignore the bMultiPageFile parameter and automatically save the scanned images in separate files. The naming of the files will be carried out as follows: if the string in pszBaseFileName is "Temp.jpg", the method will append the number of the image (0001, 0002, etc.), to the name of the file. Therefore, the output file names will be "Temp0001.jpg", "Temp0002.jpg", etc.

Should more than 9,999 pages be acquired, numbering switches to using the actual page number. So after "Temp9999.jpg", the next page scanned would be named "Temp10000.jpg", and the following page would be "Temp10001.jpg", etc. After "Temp99999.jpg", the next page scanned would be named "Temp100000.jpg", and the following page would be "Temp100001.jpg", etc.

If the file format specified in nFormat supports multipage files, this function will use the bMultiPageFile parameter to determine how to save multiple images. If bMultiPageFile is FALSE, each scanned page will be saved to a separate file, named in the same manner described in the paragraph above. If bMultiPageFile is TRUE, the name of the output file will be the exact string in pszBaseFileName (Temp.jpg) and it will be saved as a multipage file.

If uTransferMode is LTWAIN_BUFFER_MODE, and bUsePreferredBuffer is FALSE, then the function will use the user-defined buffer size in uUserBufSize. If, however, bUsePreferredBuffer is TRUE, then the function will use the TWAIN driver's preferred buffer size and will ignore uUserBufSize.

To cancel the acquire operation call the LTwain::CancelAcquire.

To stop acquire images only from the feeder of the TWAIN source, call the LTwain::StopFeeder within the LTwain::AcquireCallBack function when its fired.

You can achieve the same functionality to this function by using the LTwain::FastAcquire.

The LTWAIN_KEEPOPEN flag works only in the following cases:

1. Passed with LTWAIN_SHOW_USER_INTERFACE flag to make TWAIN user-interface appears as modeless dialog. The TWAIN data source remains open after scanning until the user closes it.
2. Passed with LTWAIN_SHOW_USER_INTERFACE and LTWAIN_MODAL_USER_INTERFACE flags to make the TWAIN user-interface appears as modal dialog. The TWAIN data source remains open after scanning until the user closes it.

Required DLLs and Libraries

• LTTWN
• For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application.

See Also

Functions

• LTwain::AcquireCallBack
• LTwain::Acquire
• LTwain::AcquireList
• LTwain::InitSession
• LTwain::EndSession
• LTwain::OpenTemplateFile
• LTwain::CloseTemplateFile
• LTwain::TemplateDlg
• LTwain::AddCapabilityToFile
• LTwain::GetNumofCapsInFile
• LTwain::GetCapabilityFromFile
• LTwain::FindFastConfig
• LTwain::GetScanConfigs
• LTwain::FreeScanConfig
• LTwain::StopFeeder.

Topics

• How to Acquire from the TWAIN Source
• TWAIN Functionality: Property Functions

Example

L_VOID CMyTwain::AcquireCallBack(L_INT nPage, L_TCHAR* pszFileName, L_BOOL bFinishScan) 
{ 
   L_TCHAR szTemp[MAX_PATH]; 
 
   if (bFinishScan) 
 
   { 
 
      wsprintf(szTemp, TEXT("The page # %d is scanned and saved to file name %s\n"), nPage, pszFileName); 
 
      MessageBox(NULL, szTemp, TEXT("Notice"), MB_OK); 
 
   } 
} 
 
L_INT LTwain__AcquireMultiExample(HWND hWnd, CMyTwain *MyClass) 
{ 
   L_INT             nRet; 
   L_BOOL            bAvailable; 
   APPLICATIONDATA   AppData; 
 
   /* Check to see if TWAIN is installed */ 
 
   bAvailable = MyClass->IsAvailable(); 
 
   if (bAvailable) 
 
   { 
 
      AppData.hWnd = hWnd;  
 
      AppData.uStructSize = sizeof(APPLICATIONDATA); 
 
      lstrcpy (AppData.szManufacturerName, TEXT("LEAD Technologies, Inc."));  
 
      lstrcpy (AppData.szAppProductFamily, TEXT("LEAD Test Applications")); 
 
      lstrcpy (AppData.szVersionInfo, TEXT("Version 1.0")); 
 
      lstrcpy (AppData.szAppName, TEXT("TWAIN Test Application")); 
 
      nRet = MyClass->InitSession(&AppData);  
      if(nRet != SUCCESS) 
         return nRet; 
 
   } 
 
   MyClass->EnableCallBack (TRUE); 
 
   nRet = MyClass->AcquireMulti( 
                              MAKE_IMAGE_PATH(TEXT("test.bmp")), 
                              LTWAIN_SHOW_USER_INTERFACE, 
                              LTWAIN_FILE_MODE, 
                              FILE_BMP, 
                              1, 
                              TRUE, 
                              0,  
                              TRUE); 
 
   if (nRet == SUCCESS) 
 
      MessageBox(hWnd, TEXT("Fast Twain function was successful"), TEXT("Notice"), MB_OK); 
 
   else 
 
      MessageBox(hWnd, TEXT("Error occurred during fast Twain function!!!"), TEXT("Error!!!"), MB_OK); 
 
   return nRet; 
 
}