Getting Started with Dynamsoft Barcode Reader SDK C++ Edition

In this guide, you will learn step by step how to build a barcode reading application with Dynamsoft Barcode Reader SDK using C++.

Learn more about Dynamsoft Barcode Reader Features

Getting Started with Dynamsoft Barcode Reader SDK C++ Edition

Installation

If you haven’t downloaded the SDK yet, download the C/C++ Package now and unpack it into a directory of your choice.

For this tutorial, we will unpack it to a pseudo directory named [INSTALLATION FOLDER]. Please change it to your preferred unpacking path for the following content.

To find out whether your environment is supported, please read the System Requirements.

Build Your First Application

Let’s start by creating a console application that demonstrates how to use the minimum code to read barcodes from an image file.

You can download the entire source code from here.

Create a New Project

For Windows

Open Visual Studio. Go to “File > New > Project…” or click “Create a new project” on the starting page, choose “Console App”, create a new Empty Project, and set the Project name as DBRCPPSample.
Add a new source file named DBRCPPSample.cpp into the project.

For Linux

Create a new source file named DBRCPPSample.cpp and place it into the folder [INSTALLATION FOLDER]/DynamsoftBarcodeReader/Samples.

Include the Library

Add headers and libraries in DBRCPPSample.cpp.

#include <iostream>
#include <string>
#include "[INSTALLATION FOLDER]/DynamsoftBarcodeReader/Include/DynamsoftCaptureVisionRouter.h"

using namespace std;
using namespace dynamsoft::license;
using namespace dynamsoft::cvr;
using namespace dynamsoft::dbr;

#if defined(_WIN64) || defined(_WIN32)
    #ifdef _WIN64
        #pragma comment(lib, "[INSTALLATION FOLDER]/DynamsoftBarcodeReader/Dist/Lib/Windows/x64/DynamsoftCorex64.lib")
        #pragma comment(lib, "[INSTALLATION FOLDER]/DynamsoftBarcodeReader/Dist/Lib/Windows/x64/DynamsoftLicensex64.lib")
        #pragma comment(lib, "[INSTALLATION FOLDER]/DynamsoftBarcodeReader/Dist/Lib/Windows/x64/DynamsoftCaptureVisionRouterx64.lib")
    #else
        #pragma comment(lib, "[INSTALLATION FOLDER]/DynamsoftBarcodeReader/Dist/Lib/Windows/x86/DynamsoftCorex86.lib")
        #pragma comment(lib, "[INSTALLATION FOLDER]/DynamsoftBarcodeReader/Dist/Lib/Windows/x86/DynamsoftLicensex86.lib")
        #pragma comment(lib, "[INSTALLATION FOLDER]/DynamsoftBarcodeReader/Dist/Lib/Windows/x86/DynamsoftCaptureVisionRouterx86.lib")
    #endif
#endif

Initialize a Capture Vision Router Instance

Initialize the License Key

char errorMsg[512];
CLicenseManager::InitLicense("DLS2eyJvcmdhbml6YXRpb25JRCI6IjIwMDAwMSJ9", errorMsg, 512);

The string “DLS2eyJvcmdhbml6YXRpb25JRCI6IjIwMDAwMSJ9” here is a free public trial license. Note that network connection is required for this license to work. Alternatively, you can request a 30-day offline free trial license from the Customer Portal.

Create a Capture Vision Router Instance

CCaptureVisionRouter* cvRouter = new CCaptureVisionRouter;

Decode and Output Results

Decode barcodes from an image file.

string imageFile = "[PATH-TO-A-BARCODE-IMAGE]";
CCapturedResult* result = cvRouter->Capture(imageFile.c_str(), CPresetTemplate::PT_READ_BARCODES);
if (result->GetErrorCode() != 0) {
    cout << "Error: " << result->GetErrorCode() << ", " << result->GetErrorString() << endl;
}
CDecodedBarcodesResult *barcodeResult = result->GetDecodedBarcodesResult();
if (barcodeResult == nullptr || barcodeResult->GetItemsCount() == 0)
{
    cout << "No barcode found." << endl;
}
else
{
    int barcodeResultItemCount = barcodeResult->GetItemsCount();
    cout << "Decoded " << barcodeResultItemCount << " barcodes" << endl;
    for (int j = 0; j < barcodeResultItemCount; j++)
    {
        const CBarcodeResultItem *barcodeResultItem = barcodeResult->GetItem(j);
        cout << "Result " << j + 1 << endl;
        cout << "Barcode Format: " << barcodeResultItem->GetFormatString() << endl;
        cout << "Barcode Text: " << barcodeResultItem->GetText() << endl;
    }
}

Release the Allocated Memory

if (barcodeResult)
    barcodeResult->Release();
result->Release();
delete cvRouter, cvRouter = NULL;

Build and Run the Project

For Windows

In Visual Studio, set the solution to build as Release|x64.
Build the project to generate the program DBRCPPSample.exe.
Copy ALL *.dll files under [INSTALLATION FOLDER]/DynamsoftBarcodeReader/Dist/Lib/Windows/x64 to the same folder as the DBRCPPSample.exe.
Copy the folder [INSTALLATION FOLDER]/DynamsoftBarcodeReader/Dist/Templates to the same folder as the DBRCPPSample.exe.
Run the program DBRCPPSample.exe.

For Linux

Open a terminal and navigate to the target directory where DBRCPPSample.cpp is located.

Build the sample:

 g++ -o DBRCPPSample DBRCPPSample.cpp -lDynamsoftCaptureVisionRouter -lDynamsoftLicense -lDynamsoftCore -lDynamsoftUtility -L ../Dist/Lib/Linux/x64 -Wl,-rpath=../Dist/Lib/Linux/x64 -std=c++11

Copy the preset template:

 cp -r ../Dist/Templates ../Dist/Lib/Linux/x64/

Run the program:
```
 ./DBRCPPSample
```

Process Multiple Images

If you need to process multiple images, follow these steps:

These steps follow the step Initialize a Capture Vision Router Instance mentioned above.

You can download the entire source code from here.

Add an Image Source as the Input

The class CDirectoryFetcher is capable of converting a local directory to an image source. We will use it to connect multiple images to the image-processing engine.

Include additional DynamsoftUtility module.

// Add the following lines
using namespace dynamsoft::utility;
#ifdef _WIN64
#pragma comment(lib, "[INSTALLATION FOLDER]/DynamsoftBarcodeReader/Dist/Lib/Windows/x64/DynamsoftUtilityx64.lib")
#else
#pragma comment(lib, "[INSTALLATION FOLDER]/DynamsoftBarcodeReader/Dist/Lib/Windows/x86/DynamsoftUtilityx86.lib")
#endif

Set up a CDirectoryFetcher object to retrieve image data sources from a directory.

CDirectoryFetcher *fetcher = new CDirectoryFetcher;
fetcher->SetDirectory("[THE DIRECTORY THAT HOLDS THE IMAGES]");
cvRouter->SetInput(fetcher);

Add a Result Receiver as the Output

Create a class MyCapturedResultReceiver to implement the CCapturedResultReceiver interface, and get the barocde results in OnDecodedBarcodesReceived callback function.

class MyCapturedResultReceiver : public CCapturedResultReceiver {
    void OnDecodedBarcodesReceived(CDecodedBarcodesResult* pResult) {
        const CFileImageTag *tag = dynamic_cast<const CFileImageTag*>(pResult->GetOriginalImageTag());
        cout << "File: " << tag->GetFilePath() << endl;
        if (pResult->GetErrorCode() != EC_OK)
        {
            cout << "Error: " << pResult->GetErrorString() << endl;
        }
        int count = pResult->GetItemsCount();
        cout << "Decoded " << count << " barcodes" << endl;
        for (int i = 0; i < count; i++) {
            const CBarcodeResultItem* barcodeResultItem = pResult->GetItem(i);                   
            if (barcodeResultItem != NULL)
            {
                cout << "Result " << i + 1 << endl;
                cout << "Barcode Format: " << barcodeResultItem->GetFormatString() << endl;
                cout << "Barcode Text: " << barcodeResultItem->GetText() << endl;
            }
        }
        cout << endl;
    }
};

Create and register a MyCapturedResultReceiver object as the result receiver.

CCapturedResultReceiver *capturedReceiver = new MyCapturedResultReceiver;
cvRouter->AddResultReceiver(capturedReceiver);

Add an Object to Listen to the Status of the Image Source

Create a class MyImageSourceStateListener to implement the CImageSourceStateListenter interface, and call StopCapturing in OnImageSourceStateReceived callback function when the state is ISS_EXHAUSTED.

class MyImageSourceStateListener : public CImageSourceStateListener {
private:
    CCaptureVisionRouter* m_router;
public:
    MyImageSourceStateListener(CCaptureVisionRouter* router) {
        m_router = router;
    }
    virtual void OnImageSourceStateReceived(ImageSourceState state)
    {
        if (state == ISS_EXHAUSTED)
            m_router->StopCapturing();
    }
};

Create and register a MyImageSourceStateListener object as the listener.

CImageSourceStateListener *listener = new MyImageSourceStateListener(cvRouter);
cvRouter->AddImageSourceStateListener(listener);

Start the Process

Call the method StartCapturing() to start processing all the images in the specified folder.

int errorCode = cvRouter->StartCapturing(CPresetTemplate::PT_READ_BARCODES, true, errorMsg, 512);

During the process, the callback function OnDecodedBarcodesReceived() is triggered each time an image finishes processing. After all images are processed, the listener function OnImageSourceStateReceived() will return the image source state as ISS_EXHAUSTED and the process is stopped with the method StopCapturing().

Release the Allocated Memory

delete cvRouter, cvRouter = NULL;
delete fetcher, fetcher = NULL;
delete listener, listener = NULL;
delete capturedReceiver, capturedReceiver = NULL;

Build and Run the Project Again

Refer to the steps in Build and Run the Project.