ByteScout Barcode Reader SDK – C++ (Unmanaged) – Image Preprocessing Filters

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ByteScout Barcode Reader SDK – C++ (Unmanaged) – Image Preprocessing Filters

ByteScout Barcode Reader SDK – C++ (Unmanaged) – Image Preprocessing Filters

ImagePreprocessingFilters.cpp

#include "stdafx.h"
 
///
/// This example demonstrates the use of image filters to improve the decoding confidence or speed.
///
 
#import "c:\\Program Files\\Bytescout BarCode Reader SDK\\net2.00\\Bytescout.BarCodeReader.tlb" raw_interfaces_only
 
using namespace Bytescout_BarCodeReader;
 
void PrintFoundBarcodes(IReaderPtr pIReader);
 
int _tmain(int argc, _TCHAR* argv[])
{
    // Initialize COM.
    HRESULT hr = CoInitialize(NULL);
 
    // Create the interface pointer.
    IReaderPtr pIReader(__uuidof(Reader));
 
    // set the registration name and key
    _bstr_t registrationName(L"DEMO");
    pIReader->put_RegistrationName(registrationName);
 
    _bstr_t registrationKey(L"DEMO");
    pIReader->put_RegistrationKey(registrationKey);
 
    // Set barcode type to find
    _BarcodeTypeSelectorPtr pBarcodeTypesToFind;
    pIReader->get_BarcodeTypesToFind(&pBarcodeTypesToFind);
    pBarcodeTypesToFind->put_Code128(VARIANT_TRUE);
 
     
    // Get image filters collection
    _ImagePreprocessingFiltersCollection* pIImageFilters;
    pIReader->get_ImagePreprocessingFilters(&pIImageFilters);
 
     
    // WORKING WITH LOW CONTRAST BARCODE IMAGES
 
    pIImageFilters->AddContrast(40);
 
    // Add contrast adjustment for low-contrast image
    _bstr_t sampleFile1(L".\\low-contrast-barcode.png");    
    wprintf(L"Image \"%s\"\n", static_cast<wchar_t*>(sampleFile1));
 
    pIReader->ReadFromFile(sampleFile1);
    PrintFoundBarcodes(pIReader);
 
    pIImageFilters->Clear();
 
 
    // WORKING WITH NOISY BARCODE IMAGES
 
    // Add median filter to lower a noise
    pIImageFilters->AddMedian();
 
    _bstr_t sampleFile2(L".\\noisy-barcode.png");
    wprintf(L"Image \"%s\"\n", static_cast<wchar_t*>(sampleFile2));
 
    pIReader->ReadFromFile(sampleFile2);
    PrintFoundBarcodes(pIReader);
 
    pIImageFilters->Clear();
 
 
    // WORKING WITH DENSE AND ILLEGIBLE BARCODES
 
    // Add the scale filter to enlarge the barcode to make gaps between bars more distinguishable
    pIImageFilters->AddScale_2(2.0);
 
    _bstr_t sampleFile3(L".\\too-dense-barcode.png");
    wprintf(L"Image \"%s\"\n", static_cast<wchar_t*>(sampleFile3));
 
    pIReader->ReadFromFile(sampleFile3);
    PrintFoundBarcodes(pIReader);
 
    pIImageFilters->Clear();
 
 
    // REMOVE EMPTY MARGINS FROM IMAGE TO SPEED UP THE PROCESSING
 
    // Add the crop filter to cut off empty margins from the image.
    // This will not improve the recognition quality but may speed up the processing 
    // if you enabled multiple barcode types to search. 
    pIImageFilters->AddCropDark();
 
    _bstr_t sampleFile4(L".\\barcode-with-large-margins.png");
    wprintf(L"Image \"%s\"\n", static_cast<wchar_t*>(sampleFile4));
 
    pIReader->ReadFromFile(sampleFile4);
    PrintFoundBarcodes(pIReader);
 
    pIImageFilters->Clear();
 
 
     
    // Uninitialize COM.
    CoUninitialize();
 
    // Wait until user press any key
    system("pause");
 
    return 0;
}
 
void PrintFoundBarcodes(IReaderPtr pIReader)
{
    // Get found barcode count
    long count;
    pIReader->get_FoundCount(&count);
 
    // Get found barcode information
    for (int i = 0; i < count; i++)
    {
        SymbologyType type;
        pIReader->GetFoundBarcodeType(i, &type);
        wprintf(L"Barcode type: %d\n", type);
 
        float confidence;
        pIReader->GetFoundBarcodeConfidence(i, &confidence);
        wprintf(L"Barcode confidence: %f\n", confidence);
 
        BSTR bstrValue;
        pIReader->GetFoundBarcodeValue(i, &bstrValue);
        wprintf(L"Barcode value: %s\n", bstrValue);
        ::SysFreeString(bstrValue);
 
        wprintf(L"\n");
    }
 
    if (count == 0)
    {
        wprintf(L"No barcodes found.\n");
    }
}

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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ByteScout Barcode Reader SDK – C++ (Unmanaged) – Image Preprocessing Filters

ByteScout Barcode Reader SDK – C++ (Unmanaged) – Image Preprocessing Filters

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