Working with Zones Using LEADTOOLS OCR Module - OmniPage Engine

To add code to an existing project that will let you recognize pages:

1. Start with the program you created in Working with Pages.

2. Define the following global IDs in Ezfunc.h in the OCR_Ltdoc2 directory:

   #define IDM_FIND_ZONES              201   
   #define IDM_ZONES_COUNT             202   
   #define IDM_ADD_VERIFICATION_ZONE   203  

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

   MAIN_MENU   MENU 
   BEGIN 
      ... 
      ... 
      MENUITEM "Find Zones"            IDM_FIND_ZONES 
      MENUITEM "Zone Count"            IDM_ZONES_COUNT 
      MENUITEM "Add Verification Zone" IDM_ADD_VERIFICATION_ZONE 
   END 

4. Define the following global variables in Ezfunc.H in the OCR_Ltdoc2 directory:

   L_INT nZoneCount; 

5. In Ezfunc.cpp in the MainWndProc procedure, add the following code to the switch ("switch(LOWORD(wParam))") statement for WM_COMMAND:

   case IDM_FIND_ZONES: 
   { 
      AUTOZONEOPTS2 ZoneOpts; 
      memset(&ZoneOpts, 0, sizeof(AUTOZONEOPTS2)); 
      ZoneOpts.uStructSize = sizeof(AUTOZONEOPTS2); 
      ZoneOpts.bEnableForceSingleColumn = TRUE; 
      ZoneOpts.bDetectNonGridedTables = TRUE; 
      L_Doc2SetZoneOptions(hDoc, &ZoneOpts); 
      nRet = L_Doc2FindZones(hDoc, 0); 
      if (nRet == SUCCESS) 
         MessageBox(NULL, TEXT("The automatic zone method found all available zones in the specified pages successfully."), TEXT("Notice!"), MB_OK); 
      else 
      { 
         wsprintf (achBuff, TEXT("Error %d in finding available zones in the specified page."), nRet); 
         MessageBox (NULL, achBuff, TEXT("Error"), MB_OK); 
      } 
    
      // Now the engine will build the OCR zone list, and we need to specify a verification event for each zone 
      // but the engine allows adding a verification event only for user zones. So, we need to duplicate these zones in the same coordinates... 
      DuplicateOcrZones(0); 
      InvalidateRect (hWnd, NULL, FALSE); 
   } 
   break; 
    
   case IDM_ZONES_COUNT: 
   { 
      nRet = L_Doc2GetZoneCount(hDoc, 0, &nZoneCount); 
      if (nRet == SUCCESS) 
      { 
         wsprintf(achBuff, TEXT("Total Zones count = %d\n"), nZoneCount); 
         MessageBox(NULL, achBuff, TEXT("Zones Count"), MB_OK); 
      } 
   } 
   break; 
    
   case IDM_ADD_VERIFICATION_ZONE: 
   { 
      ZONEDATA2 Zone; 
      L_INT i; 
      for(i=0; i<nZoneCount; i++) 
      { 
         memset(&Zone, 0, sizeof(ZONEDATA2)); 
         nRet = L_Doc2GetZone(hDoc, 0, i, &Zone, sizeof(ZONEDATA2)); 
         if (nRet == SUCCESS) 
         { 
            if ((Zone.uFlags & DOC2_ZONE_CHK_CHECKCBF_PROHIBIT) == DOC2_ZONE_CHK_CHECKCBF_PROHIBIT) 
               Zone.uFlags &= ~ DOC2_ZONE_CHK_CHECKCBF_PROHIBIT; 
            Zone.pfnCallback = VerificationCB; 
            nRet = L_Doc2UpdateZone(hDoc, 0, i, &Zone); 
            if (nRet != SUCCESS) 
            { 
               wsprintf (achBuff, TEXT("Error %d in updating zone # %d"), nRet, i); 
               MessageBox (NULL, achBuff, TEXT("Error"), MB_OK); 
            } 
         } 
      } 
   } 
   break; 

6. Add the following function at the end of the file in EZFUNC.CPP in the OCR_Ltdoc2 directory.

   L_INT EXT_CALLBACK VerificationCB(L_INT nZoneIndex, L_TCHAR * pszWord, DOC2_VERIFYCODE * pVerify, L_VOID * pUserData) 
   { 
      UNREFERENCED_PARAMETER(nZoneIndex); 
      UNREFERENCED_PARAMETER(pszWord); 
      UNREFERENCED_PARAMETER(pUserData); 
      *pVerify = DOC2_VERIFY_ACCEPT; 
      return SUCCESS; 
   } 

7. Also, add the following statement before the MainWndProc function.

   L_INT EXT_CALLBACK VerificationCB(L_INT nZoneIndex, L_TCHAR * pszWord, DOC2_VERIFYCODE * pVerify, L_VOID * pUserData); 

8. Add the following at the end of the code in EZFUNC.CPP in the OCR_Ltdoc2 directory:

   L_INT DuplicateOcrZones(L_INT nPageIndex) 
   { 
      L_INT nOcrCount=0; 
      L_Doc2GetZoneCount(hDoc, nPageIndex, &nOcrZonesCount); 
      pZONEDATA2 pZones = (pZONEDATA2)GlobalAllocPtr(GHND, sizeof(ZONEDATA2) * nOcrZonesCount); 
      if (!pZones) 
         return ERROR_NO_MEMORY; 
    
      L_INT nRet; 
      for (int i=0; i<nOcrZonesCount; i++) 
      { 
         nRet = L_Doc2GetZone(hDoc, nPageIndex, i, &pZones[i], sizeof(ZONEDATA2)); 
         if (nRet != SUCCESS) 
            return nRet; 
      } 
    
      for (int i=0; i<nOcrZonesCount; i++) 
      L_Doc2AddZone(hDoc, nPageIndex, -1, &pZones[i]); 
      return SUCCESS; 
   } 

9. Also, add the following statement before the MainWndProc function.

   L_INT DuplicateOcrZones(L_INT nPageIndex); 

10. Build SimpleLoad.exe.

11. Run SimpleLoad.exe.