Using Audio Manager APIs to detect DTMF tones in a voice call.

Using Audio Manager APIs to detect DTMF tones in a voice call

Please follow the below steps to detect DTMF tones in an active voice call. Note that only Rx direction is supported now.

1. Get the AudioFactory instance

auto &audioFactory = audioFactory::getInstance();

2. Get the AudioManager object and check for audio subsystem Readiness

std::promise<ServiceStatus> prom{};
//  Get AudioManager instance.
audioManager = audioFactory.getAudioManager([&prom](ServiceStatus serviceStatus) {
    prom.set_value(serviceStatus);
});
if (!audioManager) {
    std::cout << "Failed to get AudioManager object" << std::endl;
    return;
}

//  Check if audio subsystem is ready
//  If audio subsystem is not ready, wait for it to be ready
ServiceStatus managerStatus = audioManager->getServiceStatus();
if (managerStatus != ServiceStatus::SERVICE_AVAILABLE) {
    std::cout << "\nAudio subsystem is not ready, Please wait ..." << std::endl;
    managerStatus = prom.get_future().get();
}

//  Check the service status again.
if (managerStatus == ServiceStatus::SERVICE_AVAILABLE) {
    std::cout << "Audio Subsytem is Ready << std::endl;
} else {
    std::cout << "ERROR - Unable to initialize audio subsystem" << std::endl;
    return;
}

3. Exit the application, if SDK is unable to initialize Audio subsystem

if(isReady) {
    std::cout << " *** Audio subsystem is Ready *** " << std::endl;
} else {
    std::cout << " *** ERROR - Unable to initialize Audio subsystem " << std::endl;
    return 1;
}

4. Create an audio Stream (to be associated with Voice call session)

// Implement a response function to get the request status
void createStreamCallback(std::shared_ptr<IAudioStream> &stream, ErrorCode error) {
    if (error != ErrorCode::SUCCESS) {
        std::cout << "createStream() failed with error" << static_cast<int>(error) << std::endl;
        return;
    }
    std::cout << "createStream() succeeded." << std::endl;
    audioVoiceStream = std::dynamic_pointer_cast<IAudioVoiceStream>(stream);
}
// Create a voice stream with required configuration
status = audioManager->createStream(config, createStreamCallback);

5. Start the Voice call session

// Implement a response function to get the request status
void startAudioCallback(ErrorCode error)
{
    if (error != ErrorCode::SUCCESS) {
        std::cout << "startAudio() failed with error " << static_cast<int>(error) << std::endl;
        return;
    }
    std::cout << "startAudio() succeeded." << std::endl;
}
// Start the Voice call session
status = audioVoiceStream->startAudio(startAudioCallback);

6. Register a listener to get notifications on DTMF tone detection

// Implement a response function to get the request status
void registerListenerCallback(ErrorCode error)
{
    if (error != ErrorCode::SUCCESS) {
        std::cout << "registerListener() failed with error " << static_cast<int>(error)
                            << std::endl;
        return;
    }
    std::cout << "registerListener() succeeded." << std::endl;
}
// Instantiate MyVoiceListener
auto myDtmfToneListener = std::make_shared<MyVoiceListener>();
// Register the listener
status = audioVoiceStream->registerListener(myDtmfToneListener, registerListenerCallback);

7. De-register the listener to stop getting the notifications

status = audioVoiceStream->deRegisterListener(myDtmfToneListener);

8. Stop the Voice call session

// Implement a response function to get the request status
void stopAudioCallback(ErrorCode error)
{
    if (error != ErrorCode::SUCCESS) {
        std::cout << "stopAudio() failed with error " << static_cast<int>(error) << std::endl;
        return;
    }
    std::cout << "stopAudio() succeeded." << std::endl;
}
// Stop the Voice call session, which was started earlier
status = audioVoiceStream->stopAudio(stopAudioCallback);

9. Delete the audio stream associated with the Voice call session

// Implement a response function to get the request status
void deleteStreamCallback(ErrorCode error) {
    if (error != ErrorCode::SUCCESS) {
        std::cout << "deleteStream() failed with error" << static_cast<int>(error) << std::endl;
        return;
    }
    std::cout << "deleteStream() succeeded." << std::endl;
    audioVoiceStream->reset();
}
//Delete the Audio Stream
status = audioManager->deleteStream(std::dynamic_pointer_cast<IAudioStream>(audioVoiceStream),
                                deleteStreamCallback);