L_TwainFastAcquire2

#include "lttwn.h"

L_LTTWN_API L_INT L_TwainFastAcquire2(hSession, pszBaseFileName, nStartPageNumber, uFlags, uTransferMode, nFormat, nBitsPerPixel, bMultiPageFile, uUserBufSize, bUsePrefferedBuffer, pfnCallBack, pUserData)

Acquires image(s) from a TWAIN source and stores the image file(s) using Fast TWAIN feature.

Returns

Comments

You may call L_TwainFindFastConfig before calling this function to retrieve the best scanning configuration in pOutBestConfig parameter, and then pass the values of members in pOutBestConfig to this function.

This function was added in order to allow users to prevent already scanned files from being overwritten by a subsequent scan batch. This is accomplished by specifying the page number where the new files creation should start numbering files. If for example, three pages have been scanned while the specified pszBaseFileName parameter was "BaseFileName.bmp", the output files will have the names "BaseFileName_0001.bmp", "BaseFileName_0002.bmp" and "BaseFileName_0003.bmp". Starting a new scan while the nStartPageNumber is -1, then will overwrite the saved files. In order to avoid overwriting files, pass a 4 for the nStartPageNumber parameter so the new scanned files will start from 4. The resulting files will save as "BaseFileName_0004.bmp", "BaseFileName_0005.bmp", ...etc.

If the file format specified in nFormat does not support multi-page 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", and the nStartPageNumber is -1, 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. But if nStartPageNumber is not -1 (which should be any value bigger than zero), then the numbering will start from that value, so if for example the nStartPageNumber contains the value 4 then the output file names will be "Temp0004.jpg", "Temp0005.jpg", etc.

If the file format supports multi-page files, this function will use the bMultiPageFile parameter to determine how to save multiple images. If bMultiPageFile is set to 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 exactly the string in pszBaseFileName "Temp.jpg" and it will be saved as a multi-page file.

To cancel the acquire operation call the L_TwainCancelAcquire.

To stop acquire images only from the feeder of the TWAIN source, call the L_TwainStopFeeder function.

The LTWAIN_KEEPOPEN flag works only in the following cases:

Required DLLs and Libraries

Platforms

Windows 95 / 98 / Me, Windows 2000 / XP, Windows CE.

#define MAKE_IMAGE_PATH(pFileName) TEXT("C:\\Users\\Public\\Documents\\LEADTOOLS Images\\")pFileName 
L_VOID EXT_CALLBACK FastAcquireCB(HTWAINSESSION hSession, 
L_INT         nPage, 
L_TCHAR*      pszFileName, 
L_BOOL        bFinishScan, 
L_VOID*       pUserData) 
{ 
   UNREFERENCED_PARAMETER(hSession); 
   UNREFERENCED_PARAMETER(pUserData); 
   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 TwainFastAcquire2Example(HWND hWnd,HTWAINSESSION hSession) 
{ 
   L_INT nRet; 
   nRet = L_TwainFastAcquire2(hSession, 
   MAKE_IMAGE_PATH(TEXT("test.tif")), 
   3, // start page number to use when numbering output file names, output files should be test_0003.tif, test_0004.tif, ...etc 
   LTWAIN_SHOW_USER_INTERFACE, 
   LTWAIN_BUFFER_MODE, 
   FILE_TIF, 
   1, 
   TRUE, 
   0, 
   FALSE, 
   FastAcquireCB, NULL); 
   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; 
}