References ▼
#include "ltocr.h"
L_LTOCR_API L_INT EXT_FUNCTION L_OcrPage_GetBitmap(page, bitmapType, bitmapHandle, bitmapHandleSize)
Gets the original or processing btimap data of this page as a bitmap handle.
Handle to the OCR page.
The page type to get.
Address to BITMAPHANDLE variable to be updated with the page bitmap.
Size of the BITMAPHANDLE structure, use sizeof(BITMAPHANDLE).
| Value | Meaning |
|---|---|
| SUCCESS | The function was successful. |
| < 1 | An error occurred. Refer to Return Codes. |
Each L_OcrPage contains two versions of the image used to create it: an original and an optional processing version. The processing version usually black/white and has uniform resolution (if the original image is FAX for example) and it gets passed to the internal OCR engine during the zoning and recognition process. The L_OcrPage_AutoPreprocess method also uses the B/W image to determine if the page is inverted, skewed, or has an orientation. However, it applies the correction to both the current and processing images.
You can use L_OcrPage_GetBitmap to get a copy of the processing image, but as for the original image this function returns a reference to the original bitmap handle (not a copy) so you should not call L_FreeBitmap on this bitmap type.
You cannot set the processing image of a page; it is created automatically by the engine.
If the original image is black and white and has uniform vertical and horizontal resolution, then the engine will not create a processing image, in other words, L_OcrPage_GetBitmap will return identical BTIMAPHANDLE for both original and processing bitmap types.
If the original image has different horizontal and vertical resolution, such as a FAX image, the processing page will be have be resized to have uniform resolution.
Required DLLs and Libraries
L_INT L_OcrPage_GetBitmapExample(){int bitsPerPixel = 0;int qualityFactor = 2;L_OcrEngine ocrEngine = NULL;L_OcrPage ocrPage = NULL;BITMAPHANDLE bitmap = {0}, exportPage = {0};pLOADFILEOPTION loadOpts = NULL;pSAVEFILEOPTION saveOpts = NULL;pFILEINFO fileInfo = NULL;L_OcrProgressCallback callback = NULL;L_VOID* userData = NULL;// Create an instance of the engineL_INT retCode = L_OcrEngineManager_CreateEngine(L_OcrEngineType_Advantage, &ocrEngine);if(retCode != SUCCESS)return retCode;// Start the engine using default parametersretCode = L_OcrEngine_Startup(ocrEngine, NULL, OCR_ADVANTAGE_RUNTIME_DIR);if(retCode != SUCCESS)goto CLEANUP;// Load an image fileretCode = L_LoadBitmap(MAKE_IMAGE_PATH(L_TEXT("Ocr1.tif")), &bitmap, sizeof(BITMAPHANDLE), bitsPerPixel, ORDER_RGB, loadOpts, fileInfo);if(retCode != SUCCESS)goto CLEANUP;// Add the raster image into the OCR pageretCode = L_OcrPage_FromBitmap(ocrEngine, &ocrPage, &bitmap, L_OcrBitmapSharingMode_AutoFree, callback, userData);if(retCode != SUCCESS){L_FreeBitmap(&bitmap);goto CLEANUP;}// At this point, we have a valid page and bitmap ownership has transfered, so, we do not need to free the bitmap anymorebitmap.Flags.Allocated = 0;retCode = L_OcrPage_GetBitmap(ocrPage, L_OcrPageBitmapType_Original, &exportPage, sizeof(BITMAPHANDLE));if(retCode != SUCCESS)goto CLEANUP;// Save this image to diskbitsPerPixel = 24;L_SaveBitmap(MAKE_IMAGE_PATH(L_TEXT("OcrExported.jpg")), &exportPage, FILE_JPEG, bitsPerPixel, qualityFactor, saveOpts);CLEANUP:if(ocrPage != NULL)L_OcrPage_Destroy(ocrPage);if(L_OcrEngine_IsStarted(ocrEngine))L_OcrEngine_Shutdown(ocrEngine);L_OcrEngine_Destroy(ocrEngine);return retCode;}