L_OcrDocument_ClearPages

#include "ltocr.h"

L_LTOCR_API L_INT EXT_FUNCTION L_OcrDocument_ClearPages(document)

Clear all pages from the OCR document.

Parameters

L_OcrDocument document

Handle to the OCR document.

Returns

Value Meaning
SUCCESS The function was successful.
< 1 An error occurred. Refer to Return Codes.

Comments

Clear all pages from the OCR document.

Note: This method only works in memory-based documents.

Required DLLs and Libraries

See Also

Functions

Topics

Example

static L_INT CreateMultiPageFile(L_TCHAR* outputFileName) 
{ 
   // Create a multi-page TIF from Ocr1.tif, Ocr2.tif, Ocr3.tif and Ocr4.tif 
   HBITMAPLIST bitmapList; 
   L_INT retCode = -1; 
   SAVEFILEOPTION saveOptions = {0}; 
   retCode = L_CreateBitmapList(&bitmapList); 
   if(retCode != SUCCESS) 
      return retCode; 
 
   BITMAPHANDLE bitmaps[4]; 
   L_TCHAR *imageFiles[] = {MAKE_IMAGE_PATH(L_TEXT("OCR1.tif")),  
      MAKE_IMAGE_PATH(L_TEXT("OCR2.tif")),  
      MAKE_IMAGE_PATH(L_TEXT("OCR3.tif")),  
      MAKE_IMAGE_PATH(L_TEXT("OCR4.tif"))}; 
 
   for(L_INT i = 0; i < _countof(imageFiles); i++) 
   { 
      retCode = L_LoadBitmap(imageFiles[i], &bitmaps[i], sizeof(BITMAPHANDLE), 0, ORDER_RGB, NULL, NULL); 
      if(retCode != SUCCESS) 
         return retCode; 
 
      retCode = L_InsertBitmapListItem(bitmapList, (L_UINT)-1, &bitmaps[i]); 
      if(retCode != SUCCESS) 
         goto CLEANUP; 
   } 
 
   // Save the output file 
   retCode = L_GetDefaultSaveFileOption(&saveOptions, sizeof(SAVEFILEOPTION)); 
   if(retCode != SUCCESS) 
      goto CLEANUP; 
 
   // Save all pages 
   saveOptions.PageNumber = -1; 
   retCode = L_SaveBitmapList(outputFileName, bitmapList, FILE_CCITT_GROUP4, 1, 0, &saveOptions); 
 
CLEANUP: 
   //free all bitmaps in list & dispose of handle 
   L_DestroyBitmapList(bitmapList); 
   return retCode; 
} 
 
L_INT L_OcrDocument_ClearPagesExample() 
{ 
   L_INT retCode = -1; 
   L_OcrEngine ocrEngine = NULL; 
   L_OcrDocumentManager ocrDocumentManager = NULL; 
   L_OcrDocument ocrDocument = NULL; 
   L_OcrPage ocrPage = NULL; 
   LOADFILEOPTION loadOpts; 
   FILEINFO fileInfo; 
 
   // For this example, we need a multi-page TIF file. 
   // If you have a different sample file, replace the file name below 
   L_TCHAR* multiPageFile = MAKE_IMAGE_PATH(L_TEXT("Multipage.tif")); 
   if(CreateMultiPageFile(multiPageFile) != SUCCESS) 
      return FAILURE; 
 
   // Create an instance of the engine 
   retCode = L_OcrEngineManager_CreateEngine(L_OcrEngineType_Advantage, &ocrEngine); 
   if(retCode != SUCCESS) 
      return retCode; 
 
   // Start the engine using default parameters 
   retCode = L_OcrEngine_Startup(ocrEngine, NULL, OCR_ADVANTAGE_RUNTIME_DIR); 
   if(retCode == SUCCESS) 
   { 
      retCode = L_OcrEngine_GetDocumentManager(ocrEngine, &ocrDocumentManager); 
      if(retCode != SUCCESS) 
         goto CLEANUP; 
 
      // Create memory-based OCR document 
      retCode = L_OcrDocumentManager_CreateDocument(ocrDocumentManager, &ocrDocument, L_OcrCreateDocumentOptions_InMemory, NULL); 
      if(retCode != SUCCESS) 
         goto CLEANUP; 
 
      // Load each page of the multi-page tif file we created and process them 
      L_GetDefaultLoadFileOption(&loadOpts, sizeof(LOADFILEOPTION)); 
      retCode = L_FileInfo(multiPageFile, &fileInfo, sizeof(FILEINFO), FILEINFO_TOTALPAGES, &loadOpts); 
      if(retCode != SUCCESS) 
         goto CLEANUP; 
 
      for(L_INT pageNum = 1; pageNum <= fileInfo.TotalPages; pageNum++) 
      { 
         // Load page 
         BITMAPHANDLE bitmap = { 0 }; 
         loadOpts.PageNumber = pageNum; 
         retCode = L_LoadBitmap(multiPageFile, &bitmap, sizeof(BITMAPHANDLE), 0, ORDER_RGB, &loadOpts, &fileInfo); 
         if(retCode != SUCCESS) 
            goto CLEANUP; 
 
         // Create Ocr page 
         retCode = L_OcrPage_FromBitmap(ocrEngine, &ocrPage, &bitmap, L_OcrBitmapSharingMode_AutoFree, NULL, NULL); 
         if(retCode != SUCCESS) 
         { 
            L_FreeBitmap(&bitmap); 
            goto CLEANUP; 
         } 
 
         // Transfer ownership to the OCR page 
         bitmap.Flags.Allocated = 0; 
 
         // Find zones in the page 
         retCode = L_OcrPage_AutoZone(ocrPage, NULL, NULL); 
         if(retCode != SUCCESS) 
            goto CLEANUP; 
 
         // Recognize 
         retCode = L_OcrPage_Recognize(ocrPage, NULL, NULL); 
         if(retCode != SUCCESS) 
            goto CLEANUP; 
 
         // In Document File Mode, add OcrPage to OcrDocument after recognition 
         retCode = L_OcrDocument_AddPage(ocrDocument, ocrPage); 
         if(retCode != SUCCESS) 
            goto CLEANUP; 
      } 
 
      // Save 
      retCode = L_OcrDocument_Save(ocrDocument, MAKE_IMAGE_PATH(L_TEXT("Multipage.pdf")), DOCUMENTFORMAT_PDF, NULL, NULL); 
 
      L_UINT uPagesCount = 0; 
      retCode = L_OcrDocument_GetPageCount(ocrDocument, &uPagesCount); 
      if(retCode != SUCCESS) 
         goto CLEANUP; 
 
      // Delete the last page from the document and insert the first page in its place then re-save the document again. 
      retCode = L_OcrDocument_RemovePageAt(ocrDocument, uPagesCount - 1); 
      if(retCode != SUCCESS) 
         goto CLEANUP; 
 
      L_OcrPage ocrPage2 = NULL; 
      retCode = L_OcrDocument_GetPageAt(ocrDocument, 0, &ocrPage2); 
      if(retCode != SUCCESS) 
         goto CLEANUP; 
 
      retCode = L_OcrDocument_InsertPage(ocrDocument, uPagesCount, ocrPage2); 
      if(retCode != SUCCESS) 
         goto CLEANUP; 
 
      // double check that the page was inserted at the end of the document by getting its index 
      L_INT pageIndex = -1; 
      L_OcrDocument_IndexOfPage(ocrDocument, ocrPage2, &pageIndex); 
      assert(pageIndex == (L_INT)uPagesCount); 
 
      retCode = L_OcrDocument_Save(ocrDocument, MAKE_IMAGE_PATH(L_TEXT("Multipage2.pdf")), DOCUMENTFORMAT_PDF, NULL, NULL); 
 
      // Now clear OCR document pages 
      L_OcrDocument_ClearPages(ocrDocument); 
   } 
 
CLEANUP: 
 
   if(ocrDocument != NULL) 
      L_OcrDocument_Destroy(ocrDocument); 
 
   if(ocrEngine != NULL) 
      L_OcrEngine_Destroy(ocrEngine); 
 
   return retCode; 
} 
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