Working with Pages Using LEADTOOLS OCR Module - OmniPage Engine

To create and run a program that demonstrates how to add pages to an OCR document using Ltdoc2.h. This program will allow page insertion and to save the inserted page:

Create a new directory in the \Examples\CDLL directory called OCR_Ltdoc2.
Copy everything in the SimpleLoad directory (copy only folders content) into the OCR_Ltdoc2 directory.
Compile the project as it is and run SimpleLoad.exe to familiarize yourself with the basic program.

In the Imports.cpp, add the following lines:

#if defined(WIN64) 
   #pragma comment(lib, "..\\..\\..\\Lib"L_VER_DESIGNATOR"\\CDLL\\x64\\Ltdoc2_x.lib") 
#else 
   #pragma comment(lib, "..\\..\\..\\Lib"L_VER_DESIGNATOR"\\CDLL\\Win32\\Ltdoc2_u.lib") 
#endif // #if defined(WIN64) 
/* L_VER_DESIGNATOR is a macro that defines the version. For example for version 16 uses LTVXX_CONFIG. To set it in Visual Studio 2005, go to the main menu.  Add in Project->Property->Configuration Properties->C/C++->Preprocessor: WIN32;_DEBUG;LTVXX_CONFIG */

Add the following line in StdAfx.h in the OCR_Ltdoc2 directory:

/* LEADTOOLS main OCR document header file */ 
#include "..\..\..\include\ltdoc2.h" 
#include "..\..\..\include\ltdlg.h"

Define the following global variables in Ezfunc.h in the OCR_Ltdoc2 directory:

L_HDOC2 hDoc; /* OCR Document handle */ 
PAGEINFO2 PageInfo; 
DOC2_LANGIDS LangId[1]; 
L_BOOL bPageAdded; 
L_INT nSId; 
#define IDM_INSERT_PAGE        200 
#define IDM_SAVE_ADDED_PAGE    300

Add the following statements in Ezfunc.cpp in the WinMain function as follows:

Add the following before calling InitInstance() statement.

      /* Note that this is a sample key, which will not work in your toolkit. You should replace the sample key */ 
      L_SetLicenseFile (TEXT("MyLicenseFile", TEXT("TestKey")); 
      if (L_Doc2StartUp(&hDoc, NULL) != SUCCESS) 
         return 0; 
 
      L_Doc2CreateSettingsCollection(hDoc, -1, &nSId); 
      L_Doc2SetActiveSettingsCollection(hDoc, nSId);

Add the following after the GetMessage() loop before return statement.

       L_Doc2DeleteSettingsCollection(hDoc, nSId); 
       L_Doc2ShutDown(&hDoc);

Edit EZFUNC.RC file in the OCR_Ltdoc2 directory and add the following lines:

#include "EZFUNC.H" 
MAIN_MENU   MENU 
BEGIN 
   MENUITEM "Insert Page"        IDM_INSERT_PAGE 
   MENUITEM "Save Added Page"    IDM_SAVE_ADDED_PAGE 
END

In Ezfunc.cpp in InitApplication, change the line:

wcWindowClass.lpszMenuName = NULL;

to:

wcWindowClass.lpszMenuName = TEXT("MAIN_MENU");

In Ezfunc.cpp in MainWndProc, change the line:

Demos_CombinePath(szImagesDirectory, L_TEXT("Image1.cmp"), szFilename, _countof(szFilename));

To:

Demos_CombinePath(szImagesDirectory, L_TEXT("ocr1.tif"), szFilename, _countof(szFilename));

In Ezfunc.cpp in InitInstance, change the menu parameter (tagged as /* Use the window class menu */) in CreateWindow from NULL to LoadMenu(hInstance, MAKEINTRESOURCE("MAIN_MENU")), /*Main Menu*/

In Ezfunc.cpp under WM_CREATE, add the following code after L_LoadBitmap() if(){}:

/*After code below*/ 
nRet = L_LoadBitmap (szFilename, &LeadBitmap, sizeof(BITMAPHANDLE), 0, ORDER_BGR, NULL, NULL); 
if (nRet != SUCCESS) 
{ 
   wsprintf (achBuff, TEXT("Error %d loading %s"), nRet, (LPTSTR) szFilename); 
   MessageBox (NULL, achBuff, TEXT("Error"), MB_OK); 
   /* We have an error, so post WM_DESTROY */ 
   PostMessage (hWnd, WM_DESTROY, 0, 0); 
   return (FALSE); 
} 
 
/*After code above*/ 
/*Add code below*/ 
bPageAdded = FALSE;

In Ezfunc.cpp after WM_PAINT and before WM_DESTROY, add a new switch statement called WM_COMMAND:

/*After code below*/ 
case WM_PAINT: 
/* Get the handle to the device context */ 
hdc = BeginPaint (hWnd, &ps); 
if (LeadBitmap.Flags.Allocated)  /* Do we have an image? */ 
{ 
   if (hpalPaint) /* If we have a paint palette, select it */ 
   { 
      hPalette = SelectPalette (hdc, hpalPaint, TRUE); 
      /* Uncomment this if you do not process WM_QUERYNEWPALETTE */ 
      /* RealizePalette (hdc); */ 
   } 
 
   /* Paint the image */ 
   L_PaintDC (hdc, 
   &LeadBitmap, 
   &rLeadSource,   /* Source rectangle */ 
   NULL,           /* Default source clip area */ 
   &rLeadDest,     /* Destination rectangle */ 
   &ps.rcPaint,    /* Dest clip set by WM_PAINT */ 
   SRCCOPY);       /* Normal Paint */ 
   if (hpalPaint)         /* Return old palette */ 
      SelectPalette (hdc, hPalette, TRUE); 
} 
 
EndPaint (hWnd, &ps);     /* Return DC */ 
return (0); 
/*After code Above*/ 
/*Add code below*/ 
case WM_COMMAND: 
switch(LOWORD(wParam)) 
{ 
   case IDM_INSERT_PAGE: 
   { 
      nRet = L_Doc2AddPage(hDoc, &LeadBitmap, 1); 
      if (nRet != SUCCESS) 
      { 
         wsprintf (achBuff, TEXT("Error %d adding page at index 0"), nRet); 
         MessageBox (NULL, achBuff, TEXT("Error"), MB_OK); 
         /* We have an error, so post WM_DESTROY */ 
         PostMessage (hWnd, WM_DESTROY, 0, 0); 
         return (FALSE); 
      } 
 
      bPageAdded = TRUE; 
      L_Doc2SetActivePage(hDoc, 0); 
      memset(&PageInfo, 0, sizeof(PAGEINFO2)); 
      nRet = L_Doc2GetPageInfo (hDoc, 0, &PageInfo, sizeof(PAGEINFO2)); 
      if (nRet == SUCCESS) 
      { 
         L_INT nPageCount = 0; 
         L_Doc2GetPageCount(hDoc, &nPageCount); 
         L_Doc2SetActivePage(hDoc, nPageCount - 1); 
         /* Force paint palette creation */ 
         SendMessage (hWnd, WM_QUERYNEWPALETTE, 0, 0L); 
         RedrawWindow(hWnd,0,0,256); 
         wsprintf (achBuff, TEXT("Page Width = %d\nPage Height = %d\nPage Bits Per Pixel = %d\nPages Inserted = %d"), 
         PageInfo.nWidth, 
         PageInfo.nHeight, 
         PageInfo.nBitsPerPixel, 
         nPageCount); 
         MessageBox (NULL, achBuff, TEXT("Pages Info"), MB_OK); 
      } 
 
      LangId[0] = DOC2_LANG_ID_ENGLISH; 
      nRet = L_Doc2SelectLanguages(hDoc, LangId, 1); 
      if (nRet != SUCCESS) 
      { 
         wsprintf (achBuff, TEXT("Error %d Setting English as the default language."), nRet); 
         MessageBox (NULL, achBuff, TEXT("Error"), MB_OK); 
         RemoveDocumentPages(); 
         /* We have an error, so post WM_DESTROY */ 
         PostMessage (hWnd, WM_DESTROY, 0, 0); 
         return (FALSE); 
      } 
   } 
   break; 
 
   case IDM_SAVE_ADDED_PAGE: 
   { 
      L_INT nPageCount=0; 
      L_INT nRet = L_Doc2GetPageCount(hDoc, &nPageCount); 
      if (nRet != SUCCESS) 
      { 
         MessageBox(NULL, TEXT("Cannot get pages count"), TEXT("Error!"), MB_OK); 
         return 0; 
      } 
      if (nPageCount <=0) 
      { 
         MessageBox(NULL, TEXT("No added pages, please add pages first"), TEXT("Error!"), MB_OK); 
         return 0; 
      } 
      BITMAPHANDLE ExportBmp; 
      L_InitBitmap(&ExportBmp, sizeof(BITMAPHANDLE), 0, 0, 1); 
      nRet = L_Doc2ExportPage(hDoc, &ExportBmp, sizeof(BITMAPHANDLE), 0); 
      if (nRet != SUCCESS) 
      { 
         MessageBox(NULL, TEXT("Cannot export page to save"), TEXT("Error!"), MB_OK); 
         return 0; 
      } 
      nRet = L_SaveBitmap(TEXT("c:\\test.tif"), 
      &ExportBmp, 
      FILE_TIF, 
      ExportBmp.BitsPerPixel, 
      0, 
      NULL); 
      L_FreeBitmap(&ExportBmp); 
   } 
   break; 
} 
 
return 0; 
/*Add code above*/

Add the following function in EZFUNC.CPP in OCR_Ltdoc2 directory, add it at the end after void CalcDisplay() function:

void RemoveDocumentPages() 
{ 
   L_INT nPageCount = 0; 
   L_INT i, nRet; 
   L_TCHAR szBuffer[1024]; 
   nRet = L_Doc2GetPageCount(hDoc, &nPageCount); 
   if (nRet == SUCCESS) 
   { 
      for (i=0; i<nPageCount; i++) 
      { 
         L_Doc2CleanupPages(hDoc, TRUE); 
         nRet = L_Doc2RemovePage(hDoc, i); 
         if (nRet == SUCCESS) 
         { 
            wsprintf(szBuffer, TEXT("The page # %d was removed successfully"), i); 
            MessageBox(NULL, szBuffer, TEXT("Notice!"), MB_OK); 
         } 
      } 
   } 
}

Also, add the following statement before the MainWndProc function.
```
void RemoveDocumentPages(); 
```
On the Build menu, select Build SimpleLoad.exe.
On the Build menu, select Execute SimpleLoad.exe.

✎ NOTE

Before building project, clean solution and project files. In Build, select Clean Solution and Clean SimpleLoad).
Save this project to use it for testing other code samples.

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LEADTOOLS OCR Module - OmniPage Engine C API Help

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