ByteScout PDF Extractor SDK – C++ – PDF and OCR (Optical Character Recognition)

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ByteScout PDF Extractor SDK – C++ – PDF and OCR (Optical Character Recognition)

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ByteScout-PDF-Extractor-SDK-C-plus-plus-PDF-and-OCR-(Optical-Character-Recognition).pdf

PDF and OCR (optical character recognition) in C++ using ByteScout PDF Extractor SDK

Tutorial: how to do PDF and OCR (optical character recognition) in C++

Source code documentation samples provide quick and easy way to add a required functionality into your application. ByteScout PDF Extractor SDK was made to help with PDF and OCR (optical character recognition) in C++. ByteScout PDF Extractor SDK is the SDK is designed to help developers with pdf tables and pdf data extraction from unstructured documents like pdf, tiff, scans, images, scanned and electronic forms. The library is powered by OCR, computer vision and AI to provide unique functionality like table detection, automatic table structure extraction, data restoration, data restructuring and reconstruction. Supports PDF, TIFF, PNG, JPG images as input and can output CSV, XML, JSON formatted data. Includes full set of utilities like pdf splitter, pdf merger, searchable pdf maker and other utilities.

Fast application programming interfaces of ByteScout PDF Extractor SDK for C++ plus the instruction and the C++ code below will help you quickly learn PDF and OCR (optical character recognition). In order to implement this functionality, you should copy and paste code below into your app using code editor. Then compile and run your application. Further enhancement of the code will make it more vigorous.

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CPPExample.cpp

      	#include "stdafx.h"
	#include "comip.h"

	#import "c:\\Program Files\\Bytescout PDF Extractor SDK\\net4.00\\Bytescout.PDFExtractor.tlb" raw_interfaces_only

	using namespace Bytescout_PDFExtractor;

	int _tmain(int argc, _TCHAR* argv[])
	{
		// Initialize COM.
		HRESULT hr = CoInitializeEx(NULL, COINIT_APARTMENTTHREADED);

		// Create the interface pointer.
		_TextExtractorPtr pITextExtractor(__uuidof(TextExtractor));

		// Set the registration name and key
		// Note: You should use _bstr_t or BSTR to pass string to the library because of COM requirements
		_bstr_t bstrRegName(L"DEMO"); 
		pITextExtractor->put_RegistrationName(bstrRegName);
		
		_bstr_t bstrRegKey(L"DEMO");
		pITextExtractor->put_RegistrationKey(bstrRegKey);

		// Load sample PDF document
		_bstr_t bstrPath(L"..\\..\\sample_ocr.pdf");
		pITextExtractor->LoadDocumentFromFile(bstrPath);

		// Enable Optical Character Recognition (OCR)
		// in .Auto mode (SDK automatically checks if needs to use OCR or not)
		pITextExtractor->put_OCRMode(OCRMode_Auto);
		
		// Set the location of OCR language data files
		_bstr_t bstrOCRLangDataPath(L"c:\\Program Files\\Bytescout PDF Extractor SDK\\ocrdata");
		pITextExtractor->put_OCRLanguageDataFolder(bstrOCRLangDataPath);

		// Set OCR language
		_bstr_t bstrOCRLanguage(L"eng");
		pITextExtractor->put_OCRLanguage(bstrOCRLanguage);

		// Set PDF document rendering resolution
		pITextExtractor->put_OCRResolution(300);


		// You can also apply various preprocessing filters
		// to improve the recognition on low-quality scans.

		_ImagePreprocessingFiltersCollection* pIImagePreprocessingFilters;
		pITextExtractor->get_OCRImagePreprocessingFilters(&pIImagePreprocessingFilters);

		// Automatically deskew skewed scans
		//pIImagePreprocessingFilters->AddDeskew();

		// Remove vertical or horizontal lines (sometimes helps to avoid OCR engine's page segmentation errors)
		//pIImagePreprocessingFilters->AddVerticalLinesRemover();
		//pIImagePreprocessingFilters->AddHorizontalLinesRemover();

		// Repair broken letters
		//pIImagePreprocessingFilters->AddDilate();

		// Remove noise
		//pIImagePreprocessingFilters->AddMedian();

		// Apply Gamma Correction
		//pIImagePreprocessingFilters->AddGammaCorrection();

		// Add Contrast
		//pIImagePreprocessingFilters->AddContrast(20);


		// (!) You can use new OCRAnalyser class to find an optimal set of image preprocessing 
		// filters for your specific document.
		// See "OCR Analyser" example.


		// Save extracted text to file
		_bstr_t bstrOutputFile(L"output.txt");
		pITextExtractor->SaveTextToFile(bstrOutputFile);

		pITextExtractor->Release();

		CoUninitialize();

		return 0;
	}

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stdafx.cpp

      // stdafx.cpp : source file that includes just the standard includes
// CPPExample.pch will be the pre-compiled header
// stdafx.obj will contain the pre-compiled type information

#include "stdafx.h"

// TODO: reference any additional headers you need in STDAFX.H
// and not in this file

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stdafx.h

      // stdafx.h : include file for standard system include files,
// or project specific include files that are used frequently, but
// are changed infrequently
//

#pragma once

#include "targetver.h"

#include <stdio.h>
#include <tchar.h>



// TODO: reference additional headers your program requires here

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targetver.h

      #pragma once

// Including SDKDDKVer.h defines the highest available Windows platform.

// If you wish to build your application for a previous Windows platform, include WinSDKVer.h and
// set the _WIN32_WINNT macro to the platform you wish to support before including SDKDDKVer.h.

#include <SDKDDKVer.h>