sdrangel/plugins/channeltx/modnfm/nfmmod.cpp

///////////////////////////////////////////////////////////////////////////////////
// Copyright (C) 2016 Edouard Griffiths, F4EXB                                   //
//                                                                               //
// This program is free software; you can redistribute it and/or modify          //
// it under the terms of the GNU General Public License as published by          //
// the Free Software Foundation as version 3 of the License, or                  //
// (at your option) any later version.                                           //
//                                                                               //
// This program is distributed in the hope that it will be useful,               //
// but WITHOUT ANY WARRANTY; without even the implied warranty of                //
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the                  //
// GNU General Public License V3 for more details.                               //
//                                                                               //
// You should have received a copy of the GNU General Public License             //
// along with this program. If not, see <http://www.gnu.org/licenses/>.          //
///////////////////////////////////////////////////////////////////////////////////

#include <QTime>
#include <QDebug>
#include <QMutexLocker>
#include <QNetworkAccessManager>
#include <QNetworkReply>
#include <QBuffer>

#include "SWGChannelSettings.h"
#include "SWGCWKeyerSettings.h"
#include "SWGChannelReport.h"
#include "SWGNFMModReport.h"

#include <stdio.h>
#include <complex.h>
#include <algorithm>

#include "dsp/upchannelizer.h"
#include "dsp/dspengine.h"
#include "dsp/dspcommands.h"
#include "device/deviceapi.h"
#include "dsp/threadedbasebandsamplesource.h"
#include "util/db.h"

#include "nfmmod.h"

MESSAGE_CLASS_DEFINITION(NFMMod::MsgConfigureNFMMod, Message)
MESSAGE_CLASS_DEFINITION(NFMMod::MsgConfigureChannelizer, Message)
MESSAGE_CLASS_DEFINITION(NFMMod::MsgConfigureFileSourceName, Message)
MESSAGE_CLASS_DEFINITION(NFMMod::MsgConfigureFileSourceSeek, Message)
MESSAGE_CLASS_DEFINITION(NFMMod::MsgConfigureFileSourceStreamTiming, Message)
MESSAGE_CLASS_DEFINITION(NFMMod::MsgReportFileSourceStreamData, Message)
MESSAGE_CLASS_DEFINITION(NFMMod::MsgReportFileSourceStreamTiming, Message)

const QString NFMMod::m_channelIdURI = "sdrangel.channeltx.modnfm";
const QString NFMMod::m_channelId = "NFMMod";
const int NFMMod::m_levelNbSamples = 480; // every 10ms

NFMMod::NFMMod(DeviceAPI *deviceAPI) :
    ChannelAPI(m_channelIdURI, ChannelAPI::StreamSingleSource),
	m_deviceAPI(deviceAPI),
	m_basebandSampleRate(48000),
	m_outputSampleRate(48000),
	m_inputFrequencyOffset(0),
	m_modPhasor(0.0f),
    m_audioFifo(4800),
    m_feedbackAudioFifo(48000),
	m_settingsMutex(QMutex::Recursive),
	m_fileSize(0),
	m_recordLength(0),
	m_sampleRate(48000),
	m_levelCalcCount(0),
	m_peakLevel(0.0f),
	m_levelSum(0.0f)
{
	setObjectName(m_channelId);

	m_audioBuffer.resize(1<<14);
	m_audioBufferFill = 0;

	m_feedbackAudioBuffer.resize(1<<14);
	m_feedbackAudioBufferFill = 0;

	m_magsq = 0.0;

	DSPEngine::instance()->getAudioDeviceManager()->addAudioSource(&m_audioFifo, getInputMessageQueue());
	m_audioSampleRate = DSPEngine::instance()->getAudioDeviceManager()->getInputSampleRate();

    DSPEngine::instance()->getAudioDeviceManager()->addAudioSink(&m_feedbackAudioFifo, getInputMessageQueue());
    m_feedbackAudioSampleRate = DSPEngine::instance()->getAudioDeviceManager()->getOutputSampleRate();
    applyFeedbackAudioSampleRate(m_feedbackAudioSampleRate);

    m_lowpass.create(301, m_audioSampleRate, 250.0);
	m_toneNco.setFreq(1000.0, m_audioSampleRate);
	m_ctcssNco.setFreq(88.5, m_audioSampleRate);
    m_cwKeyer.setSampleRate(m_audioSampleRate);
    m_cwKeyer.reset();

    applyChannelSettings(m_basebandSampleRate, m_outputSampleRate, m_inputFrequencyOffset, true);
    applySettings(m_settings, true);

    m_channelizer = new UpChannelizer(this);
    m_threadedChannelizer = new ThreadedBasebandSampleSource(m_channelizer, this);
    m_deviceAPI->addChannelSource(m_threadedChannelizer);
    m_deviceAPI->addChannelSourceAPI(this);

    m_networkManager = new QNetworkAccessManager();
    connect(m_networkManager, SIGNAL(finished(QNetworkReply*)), this, SLOT(networkManagerFinished(QNetworkReply*)));
}

NFMMod::~NFMMod()
{
    disconnect(m_networkManager, SIGNAL(finished(QNetworkReply*)), this, SLOT(networkManagerFinished(QNetworkReply*)));
    delete m_networkManager;
    DSPEngine::instance()->getAudioDeviceManager()->removeAudioSink(&m_feedbackAudioFifo);
    DSPEngine::instance()->getAudioDeviceManager()->removeAudioSource(&m_audioFifo);
    m_deviceAPI->removeChannelSourceAPI(this);
    m_deviceAPI->removeChannelSource(m_threadedChannelizer);
    delete m_threadedChannelizer;
    delete m_channelizer;
}

void NFMMod::pull(Sample& sample)
{
	if (m_settings.m_channelMute)
	{
		sample.m_real = 0.0f;
		sample.m_imag = 0.0f;
		return;
	}

	Complex ci;

	m_settingsMutex.lock();

    if (m_interpolatorDistance > 1.0f) // decimate
    {
    	modulateSample();

        while (!m_interpolator.decimate(&m_interpolatorDistanceRemain, m_modSample, &ci))
        {
        	modulateSample();
        }
    }
    else
    {
        if (m_interpolator.interpolate(&m_interpolatorDistanceRemain, m_modSample, &ci))
        {
        	modulateSample();
        }
    }

    m_interpolatorDistanceRemain += m_interpolatorDistance;

    ci *= m_carrierNco.nextIQ(); // shift to carrier frequency

    m_settingsMutex.unlock();

    double magsq = ci.real() * ci.real() + ci.imag() * ci.imag();
	magsq /= (SDR_TX_SCALED*SDR_TX_SCALED);
	m_movingAverage(magsq);
	m_magsq = m_movingAverage.asDouble();

	sample.m_real = (FixReal) ci.real();
	sample.m_imag = (FixReal) ci.imag();
}

void NFMMod::pullAudio(int nbSamples)
{
    unsigned int nbSamplesAudio = nbSamples * ((Real) m_audioSampleRate / (Real) m_basebandSampleRate);

    if (nbSamplesAudio > m_audioBuffer.size())
    {
        m_audioBuffer.resize(nbSamplesAudio);
    }

    m_audioFifo.read(reinterpret_cast<quint8*>(&m_audioBuffer[0]), nbSamplesAudio);
    m_audioBufferFill = 0;
}

void NFMMod::modulateSample()
{
	Real t;

    pullAF(t);

    if (m_settings.m_feedbackAudioEnable) {
        pushFeedback(t * m_settings.m_feedbackVolumeFactor * 16384.0f);
    }

    calculateLevel(t);
    m_audioBufferFill++;

    if (m_settings.m_ctcssOn)
    {
        m_modPhasor += (m_settings.m_fmDeviation / (float) m_audioSampleRate) * (0.85f * m_bandpass.filter(t) + 0.15f * 378.0f * m_ctcssNco.next()) * (M_PI / 378.0f);
    }
    else
    {
        // 378 = 302 * 1.25; 302 = number of filter taps (established experimentally)
        m_modPhasor += (m_settings.m_fmDeviation / (float) m_audioSampleRate) * m_bandpass.filter(t) * (M_PI / 378.0f);
    }

    m_modSample.real(cos(m_modPhasor) * 0.891235351562f * SDR_TX_SCALEF); // -1 dB
    m_modSample.imag(sin(m_modPhasor) * 0.891235351562f * SDR_TX_SCALEF);
}

void NFMMod::pullAF(Real& sample)
{
    switch (m_settings.m_modAFInput)
    {
    case NFMModSettings::NFMModInputTone:
        sample = m_toneNco.next();
        break;
    case NFMModSettings::NFMModInputFile:
        // sox f4exb_call.wav --encoding float --endian little f4exb_call.raw
        // ffplay -f f32le -ar 48k -ac 1 f4exb_call.raw
        if (m_ifstream.is_open())
        {
            if (m_ifstream.eof())
            {
            	if (m_settings.m_playLoop)
            	{
                    m_ifstream.clear();
                    m_ifstream.seekg(0, std::ios::beg);
            	}
            }

            if (m_ifstream.eof())
            {
            	sample = 0.0f;
            }
            else
            {
            	m_ifstream.read(reinterpret_cast<char*>(&sample), sizeof(Real));
            	sample *= m_settings.m_volumeFactor;
            }
        }
        else
        {
            sample = 0.0f;
        }
        break;
    case NFMModSettings::NFMModInputAudio:
        sample = ((m_audioBuffer[m_audioBufferFill].l + m_audioBuffer[m_audioBufferFill].r) / 65536.0f) * m_settings.m_volumeFactor;
        break;
    case NFMModSettings::NFMModInputCWTone:
        Real fadeFactor;

        if (m_cwKeyer.getSample())
        {
            m_cwKeyer.getCWSmoother().getFadeSample(true, fadeFactor);
            sample = m_toneNco.next() * fadeFactor;
        }
        else
        {
            if (m_cwKeyer.getCWSmoother().getFadeSample(false, fadeFactor))
            {
                sample = m_toneNco.next() * fadeFactor;
            }
            else
            {
                sample = 0.0f;
                m_toneNco.setPhase(0);
            }
        }
        break;
    case NFMModSettings::NFMModInputNone:
    default:
        sample = 0.0f;
        break;
    }
}

void NFMMod::pushFeedback(Real sample)
{
    Complex c(sample, sample);
    Complex ci;

    if (m_feedbackInterpolatorDistance < 1.0f) // interpolate
    {
        while (!m_feedbackInterpolator.interpolate(&m_feedbackInterpolatorDistanceRemain, c, &ci))
        {
            processOneSample(ci);
            m_feedbackInterpolatorDistanceRemain += m_feedbackInterpolatorDistance;
        }
    }
    else // decimate
    {
        if (m_feedbackInterpolator.decimate(&m_feedbackInterpolatorDistanceRemain, c, &ci))
        {
            processOneSample(ci);
            m_feedbackInterpolatorDistanceRemain += m_feedbackInterpolatorDistance;
        }
    }
}

void NFMMod::processOneSample(Complex& ci)
{
    m_feedbackAudioBuffer[m_feedbackAudioBufferFill].l = ci.real();
    m_feedbackAudioBuffer[m_feedbackAudioBufferFill].r = ci.imag();
    ++m_feedbackAudioBufferFill;

    if (m_feedbackAudioBufferFill >= m_feedbackAudioBuffer.size())
    {
        uint res = m_feedbackAudioFifo.write((const quint8*)&m_feedbackAudioBuffer[0], m_feedbackAudioBufferFill);

        if (res != m_feedbackAudioBufferFill)
        {
            qDebug("AMDemod::pushFeedback: %u/%u audio samples written m_feedbackInterpolatorDistance: %f",
                res, m_feedbackAudioBufferFill, m_feedbackInterpolatorDistance);
            m_feedbackAudioFifo.clear();
        }

        m_feedbackAudioBufferFill = 0;
    }
}

void NFMMod::calculateLevel(Real& sample)
{
    if (m_levelCalcCount < m_levelNbSamples)
    {
        m_peakLevel = std::max(std::fabs(m_peakLevel), sample);
        m_levelSum += sample * sample;
        m_levelCalcCount++;
    }
    else
    {
        qreal rmsLevel = sqrt(m_levelSum / m_levelNbSamples);
        //qDebug("NFMMod::calculateLevel: %f %f", rmsLevel, m_peakLevel);
        emit levelChanged(rmsLevel, m_peakLevel, m_levelNbSamples);
        m_peakLevel = 0.0f;
        m_levelSum = 0.0f;
        m_levelCalcCount = 0;
    }
}

void NFMMod::start()
{
	qDebug() << "NFMMod::start: m_outputSampleRate: " << m_outputSampleRate
			<< " m_inputFrequencyOffset: " << m_inputFrequencyOffset;

	m_audioFifo.clear();
	applyChannelSettings(m_basebandSampleRate, m_outputSampleRate, m_inputFrequencyOffset, true);
}

void NFMMod::stop()
{
}

bool NFMMod::handleMessage(const Message& cmd)
{
	if (UpChannelizer::MsgChannelizerNotification::match(cmd))
	{
		UpChannelizer::MsgChannelizerNotification& notif = (UpChannelizer::MsgChannelizerNotification&) cmd;
        qDebug() << "NFMMod::handleMessage: UpChannelizer::MsgChannelizerNotification";

        applyChannelSettings(notif.getBasebandSampleRate(), notif.getSampleRate(), notif.getFrequencyOffset());

		return true;
	}
    else if (MsgConfigureChannelizer::match(cmd))
    {
        MsgConfigureChannelizer& cfg = (MsgConfigureChannelizer&) cmd;
        qDebug() << "NFMMod::handleMessage: MsgConfigureChannelizer:"
                << " getSampleRate: " << cfg.getSampleRate()
                << " getCenterFrequency: " << cfg.getCenterFrequency();

        m_channelizer->configure(m_channelizer->getInputMessageQueue(),
            cfg.getSampleRate(),
            cfg.getCenterFrequency());

        return true;
    }
    else if (MsgConfigureNFMMod::match(cmd))
    {
        MsgConfigureNFMMod& cfg = (MsgConfigureNFMMod&) cmd;
        qDebug() << "NFMMod::handleMessage: MsgConfigureNFMMod";

        applySettings(cfg.getSettings(), cfg.getForce());

        return true;
    }
	else if (MsgConfigureFileSourceName::match(cmd))
    {
        MsgConfigureFileSourceName& conf = (MsgConfigureFileSourceName&) cmd;
        m_fileName = conf.getFileName();
        openFileStream();
	    qDebug() << "NFMMod::handleMessage: MsgConfigureFileSourceName:"
	             << " m_fileName: " << m_fileName;
        return true;
    }
    else if (MsgConfigureFileSourceSeek::match(cmd))
    {
        MsgConfigureFileSourceSeek& conf = (MsgConfigureFileSourceSeek&) cmd;
        int seekPercentage = conf.getPercentage();
        seekFileStream(seekPercentage);
        qDebug() << "NFMMod::handleMessage: MsgConfigureFileSourceSeek:"
                 << " seekPercentage: " << seekPercentage;

        return true;
    }
    else if (MsgConfigureFileSourceStreamTiming::match(cmd))
    {
    	std::size_t samplesCount;

    	if (m_ifstream.eof()) {
    		samplesCount = m_fileSize / sizeof(Real);
    	} else {
    		samplesCount = m_ifstream.tellg() / sizeof(Real);
    	}

    	MsgReportFileSourceStreamTiming *report;
        report = MsgReportFileSourceStreamTiming::create(samplesCount);
        getMessageQueueToGUI()->push(report);

        return true;
    }
    else if (CWKeyer::MsgConfigureCWKeyer::match(cmd))
    {
        const CWKeyer::MsgConfigureCWKeyer& cfg = (CWKeyer::MsgConfigureCWKeyer&) cmd;

        if (m_settings.m_useReverseAPI) {
            webapiReverseSendCWSettings(cfg.getSettings());
        }

        return true;
    }
    else if (DSPConfigureAudio::match(cmd))
    {
        DSPConfigureAudio& cfg = (DSPConfigureAudio&) cmd;
        uint32_t sampleRate = cfg.getSampleRate();
        DSPConfigureAudio::AudioType audioType = cfg.getAudioType();

        qDebug() << "NFMMod::handleMessage: DSPConfigureAudio:"
                << " sampleRate: " << sampleRate
                << " audioType: " << audioType;

        if (audioType == DSPConfigureAudio::AudioInput)
        {
            if (sampleRate != m_audioSampleRate) {
                applyAudioSampleRate(sampleRate);
            }
        }
        else if (audioType == DSPConfigureAudio::AudioOutput)
        {
            if (sampleRate != m_audioSampleRate) {
                applyFeedbackAudioSampleRate(sampleRate);
            }
        }

        return true;
    }
    else if (DSPSignalNotification::match(cmd))
    {
        return true;
    }
	else
	{
		return false;
	}
}

void NFMMod::openFileStream()
{
    if (m_ifstream.is_open()) {
        m_ifstream.close();
    }

    m_ifstream.open(m_fileName.toStdString().c_str(), std::ios::binary | std::ios::ate);
    m_fileSize = m_ifstream.tellg();
    m_ifstream.seekg(0,std::ios_base::beg);

    m_sampleRate = 48000; // fixed rate
    m_recordLength = m_fileSize / (sizeof(Real) * m_sampleRate);

    qDebug() << "NFMMod::openFileStream: " << m_fileName.toStdString().c_str()
            << " fileSize: " << m_fileSize << "bytes"
            << " length: " << m_recordLength << " seconds";

    MsgReportFileSourceStreamData *report;
    report = MsgReportFileSourceStreamData::create(m_sampleRate, m_recordLength);
    getMessageQueueToGUI()->push(report);
}

void NFMMod::seekFileStream(int seekPercentage)
{
    QMutexLocker mutexLocker(&m_settingsMutex);

    if (m_ifstream.is_open())
    {
        int seekPoint = ((m_recordLength * seekPercentage) / 100) * m_sampleRate;
        seekPoint *= sizeof(Real);
        m_ifstream.clear();
        m_ifstream.seekg(seekPoint, std::ios::beg);
    }
}

void NFMMod::applyAudioSampleRate(int sampleRate)
{
    qDebug("NFMMod::applyAudioSampleRate: %d", sampleRate);

    MsgConfigureChannelizer* channelConfigMsg = MsgConfigureChannelizer::create(
            sampleRate, m_settings.m_inputFrequencyOffset);
    m_inputMessageQueue.push(channelConfigMsg);

    m_settingsMutex.lock();

    m_interpolatorDistanceRemain = 0;
    m_interpolatorConsumed = false;
    m_interpolatorDistance = (Real) sampleRate / (Real) m_outputSampleRate;
    m_interpolator.create(48, sampleRate, m_settings.m_rfBandwidth / 2.2, 3.0);
    m_lowpass.create(301, sampleRate, 250.0);
    m_bandpass.create(301, sampleRate, 300.0, m_settings.m_afBandwidth);
    m_toneNco.setFreq(m_settings.m_toneFrequency, sampleRate);
    m_ctcssNco.setFreq(NFMModSettings::getCTCSSFreq(m_settings.m_ctcssIndex), sampleRate);
    m_cwKeyer.setSampleRate(sampleRate);

    m_settingsMutex.unlock();

    m_audioSampleRate = sampleRate;
    applyFeedbackAudioSampleRate(m_feedbackAudioSampleRate);
}

void NFMMod::applyFeedbackAudioSampleRate(unsigned int sampleRate)
{
    qDebug("NFMMod::applyFeedbackAudioSampleRate: %u", sampleRate);

    m_settingsMutex.lock();

    m_feedbackInterpolatorDistanceRemain = 0;
    m_feedbackInterpolatorConsumed = false;
    m_feedbackInterpolatorDistance = (Real) sampleRate / (Real) m_audioSampleRate;
    Real cutoff = std::min(sampleRate, m_audioSampleRate) / 2.2f;
    m_feedbackInterpolator.create(48, sampleRate, cutoff, 3.0);

    m_settingsMutex.unlock();

    m_feedbackAudioSampleRate = sampleRate;
}

void NFMMod::applyChannelSettings(int basebandSampleRate, int outputSampleRate, int inputFrequencyOffset, bool force)
{
    qDebug() << "NFMMod::applyChannelSettings:"
            << " basebandSampleRate: " << basebandSampleRate
            << " outputSampleRate: " << outputSampleRate
            << " inputFrequencyOffset: " << inputFrequencyOffset;

    if ((inputFrequencyOffset != m_inputFrequencyOffset) ||
        (outputSampleRate != m_outputSampleRate) || force)
    {
        m_settingsMutex.lock();
        m_carrierNco.setFreq(inputFrequencyOffset, outputSampleRate);
        m_settingsMutex.unlock();
    }

    if ((outputSampleRate != m_outputSampleRate) || force)
    {
        m_settingsMutex.lock();
        m_interpolatorDistanceRemain = 0;
        m_interpolatorConsumed = false;
        m_interpolatorDistance = (Real) m_audioSampleRate / (Real) outputSampleRate;
        m_interpolator.create(48, m_audioSampleRate, m_settings.m_rfBandwidth / 2.2, 3.0);
        m_settingsMutex.unlock();
    }

    m_basebandSampleRate = basebandSampleRate;
    m_outputSampleRate = outputSampleRate;
    m_inputFrequencyOffset = inputFrequencyOffset;
}

void NFMMod::applySettings(const NFMModSettings& settings, bool force)
{
    qDebug() << "NFMMod::applySettings:"
            << " m_inputFrequencyOffset: " << settings.m_inputFrequencyOffset
            << " m_rfBandwidth: " << settings.m_rfBandwidth
            << " m_afBandwidth: " << settings.m_afBandwidth
            << " m_fmDeviation: " << settings.m_fmDeviation
            << " m_volumeFactor: " << settings.m_volumeFactor
            << " m_toneFrequency: " << settings.m_toneFrequency
            << " m_ctcssIndex: " << settings.m_ctcssIndex
            << " m_ctcssOn: " << settings.m_ctcssOn
            << " m_channelMute: " << settings.m_channelMute
            << " m_playLoop: " << settings.m_playLoop
            << " m_modAFInput " << settings.m_modAFInput
            << " m_audioDeviceName: " << settings.m_audioDeviceName
            << " m_useReverseAPI: " << settings.m_useReverseAPI
            << " m_reverseAPIAddress: " << settings.m_reverseAPIAddress
            << " m_reverseAPIAddress: " << settings.m_reverseAPIPort
            << " m_reverseAPIDeviceIndex: " << settings.m_reverseAPIDeviceIndex
            << " m_reverseAPIChannelIndex: " << settings.m_reverseAPIChannelIndex
            << " force: " << force;

    QList<QString> reverseAPIKeys;

    if ((settings.m_inputFrequencyOffset != m_settings.m_inputFrequencyOffset) || force) {
        reverseAPIKeys.append("inputFrequencyOffset");
    }

    if ((settings.m_fmDeviation != m_settings.m_fmDeviation) || force) {
        reverseAPIKeys.append("fmDeviation");
    }

    if ((settings.m_volumeFactor != m_settings.m_volumeFactor) || force) {
        reverseAPIKeys.append("volumeFactor");
    }

    if ((settings.m_ctcssOn != m_settings.m_ctcssOn) || force) {
        reverseAPIKeys.append("ctcssOn");
    }

    if ((settings.m_channelMute != m_settings.m_channelMute) || force) {
        reverseAPIKeys.append("channelMute");
    }

    if ((settings.m_playLoop != m_settings.m_playLoop) || force) {
        reverseAPIKeys.append("playLoop");
    }

    if ((settings.m_modAFInput != m_settings.m_modAFInput) || force) {
        reverseAPIKeys.append("modAFInput");
    }

    if((settings.m_rfBandwidth != m_settings.m_rfBandwidth) || force)
    {
        reverseAPIKeys.append("rfBandwidth");
        m_settingsMutex.lock();
        m_interpolatorDistanceRemain = 0;
        m_interpolatorConsumed = false;
        m_interpolatorDistance = (Real) m_audioSampleRate / (Real) m_outputSampleRate;
        m_interpolator.create(48, m_audioSampleRate, settings.m_rfBandwidth / 2.2, 3.0);
        m_settingsMutex.unlock();
    }

    if ((settings.m_afBandwidth != m_settings.m_afBandwidth) || force)
    {
        reverseAPIKeys.append("afBandwidth");
        m_settingsMutex.lock();
        m_lowpass.create(301, m_audioSampleRate, 250.0);
        m_bandpass.create(301, m_audioSampleRate, 300.0, settings.m_afBandwidth);
        m_settingsMutex.unlock();
    }

    if ((settings.m_toneFrequency != m_settings.m_toneFrequency) || force)
    {
        reverseAPIKeys.append("toneFrequency");
        m_settingsMutex.lock();
        m_toneNco.setFreq(settings.m_toneFrequency, m_audioSampleRate);
        m_settingsMutex.unlock();
    }

    if ((settings.m_ctcssIndex != m_settings.m_ctcssIndex) || force)
    {
        reverseAPIKeys.append("ctcssIndex");
        m_settingsMutex.lock();
        m_ctcssNco.setFreq(NFMModSettings::getCTCSSFreq(settings.m_ctcssIndex), m_audioSampleRate);
        m_settingsMutex.unlock();
    }

    if ((settings.m_audioDeviceName != m_settings.m_audioDeviceName) || force)
    {
        reverseAPIKeys.append("audioDeviceName");
        AudioDeviceManager *audioDeviceManager = DSPEngine::instance()->getAudioDeviceManager();
        int audioDeviceIndex = audioDeviceManager->getInputDeviceIndex(settings.m_audioDeviceName);
        audioDeviceManager->addAudioSource(&m_audioFifo, getInputMessageQueue(), audioDeviceIndex);
        uint32_t audioSampleRate = audioDeviceManager->getInputSampleRate(audioDeviceIndex);

        if (m_audioSampleRate != audioSampleRate) {
            reverseAPIKeys.append("audioSampleRate");
            applyAudioSampleRate(audioSampleRate);
        }
    }

    if ((settings.m_feedbackAudioDeviceName != m_settings.m_feedbackAudioDeviceName) || force)
    {
        reverseAPIKeys.append("feedbackAudioDeviceName");
        AudioDeviceManager *audioDeviceManager = DSPEngine::instance()->getAudioDeviceManager();
        int audioDeviceIndex = audioDeviceManager->getOutputDeviceIndex(settings.m_feedbackAudioDeviceName);
        audioDeviceManager->addAudioSink(&m_feedbackAudioFifo, getInputMessageQueue(), audioDeviceIndex);
        uint32_t audioSampleRate = audioDeviceManager->getOutputSampleRate(audioDeviceIndex);

        if (m_feedbackAudioSampleRate != audioSampleRate) {
            reverseAPIKeys.append("feedbackAudioSampleRate");
            applyFeedbackAudioSampleRate(audioSampleRate);
        }
    }

    if (settings.m_useReverseAPI)
    {
        bool fullUpdate = ((m_settings.m_useReverseAPI != settings.m_useReverseAPI) && settings.m_useReverseAPI) ||
                (m_settings.m_reverseAPIAddress != settings.m_reverseAPIAddress) ||
                (m_settings.m_reverseAPIPort != settings.m_reverseAPIPort) ||
                (m_settings.m_reverseAPIDeviceIndex != settings.m_reverseAPIDeviceIndex) ||
                (m_settings.m_reverseAPIChannelIndex != settings.m_reverseAPIChannelIndex);
        webapiReverseSendSettings(reverseAPIKeys, settings, fullUpdate || force);
    }

    m_settings = settings;
}

QByteArray NFMMod::serialize() const
{
    return m_settings.serialize();
}

bool NFMMod::deserialize(const QByteArray& data)
{
    bool success = true;

    if (!m_settings.deserialize(data))
    {
        m_settings.resetToDefaults();
        success = false;
    }

    MsgConfigureChannelizer *msgChan = MsgConfigureChannelizer::create(
            48000, m_settings.m_inputFrequencyOffset);
    m_inputMessageQueue.push(msgChan);

    MsgConfigureNFMMod *msg = MsgConfigureNFMMod::create(m_settings, true);
    m_inputMessageQueue.push(msg);

    return success;
}

int NFMMod::webapiSettingsGet(
                SWGSDRangel::SWGChannelSettings& response,
                QString& errorMessage)
{
    (void) errorMessage;
    response.setNfmModSettings(new SWGSDRangel::SWGNFMModSettings());
    response.getNfmModSettings()->init();
    webapiFormatChannelSettings(response, m_settings);

    SWGSDRangel::SWGCWKeyerSettings *apiCwKeyerSettings = response.getNfmModSettings()->getCwKeyer();
    const CWKeyerSettings& cwKeyerSettings = m_cwKeyer.getSettings();
    CWKeyer::webapiFormatChannelSettings(apiCwKeyerSettings, cwKeyerSettings);

    return 200;
}

int NFMMod::webapiSettingsPutPatch(
                bool force,
                const QStringList& channelSettingsKeys,
                SWGSDRangel::SWGChannelSettings& response,
                QString& errorMessage)
{
    (void) errorMessage;
    NFMModSettings settings = m_settings;
    webapiUpdateChannelSettings(settings, channelSettingsKeys, response);

    if (channelSettingsKeys.contains("cwKeyer"))
    {
        SWGSDRangel::SWGCWKeyerSettings *apiCwKeyerSettings = response.getNfmModSettings()->getCwKeyer();
        CWKeyerSettings cwKeyerSettings = m_cwKeyer.getSettings();
        CWKeyer::webapiSettingsPutPatch(channelSettingsKeys, cwKeyerSettings, apiCwKeyerSettings);

        CWKeyer::MsgConfigureCWKeyer *msgCwKeyer = CWKeyer::MsgConfigureCWKeyer::create(cwKeyerSettings, force);
        m_cwKeyer.getInputMessageQueue()->push(msgCwKeyer);

        if (m_guiMessageQueue) // forward to GUI if any
        {
            CWKeyer::MsgConfigureCWKeyer *msgCwKeyerToGUI = CWKeyer::MsgConfigureCWKeyer::create(cwKeyerSettings, force);
            m_guiMessageQueue->push(msgCwKeyerToGUI);
        }
    }

    if (m_settings.m_inputFrequencyOffset != settings.m_inputFrequencyOffset)
    {
        NFMMod::MsgConfigureChannelizer *msgChan = NFMMod::MsgConfigureChannelizer::create(
                m_audioSampleRate, settings.m_inputFrequencyOffset);
        m_inputMessageQueue.push(msgChan);
    }

    MsgConfigureNFMMod *msg = MsgConfigureNFMMod::create(settings, force);
    m_inputMessageQueue.push(msg);

    if (m_guiMessageQueue) // forward to GUI if any
    {
        MsgConfigureNFMMod *msgToGUI = MsgConfigureNFMMod::create(settings, force);
        m_guiMessageQueue->push(msgToGUI);
    }

    webapiFormatChannelSettings(response, settings);

    return 200;
}

void NFMMod::webapiUpdateChannelSettings(
        NFMModSettings& settings,
        const QStringList& channelSettingsKeys,
        SWGSDRangel::SWGChannelSettings& response)
{
    if (channelSettingsKeys.contains("afBandwidth")) {
        settings.m_afBandwidth = response.getNfmModSettings()->getAfBandwidth();
    }
    if (channelSettingsKeys.contains("channelMute")) {
        settings.m_channelMute = response.getNfmModSettings()->getChannelMute() != 0;
    }
    if (channelSettingsKeys.contains("ctcssIndex")) {
        settings.m_ctcssIndex = response.getNfmModSettings()->getCtcssIndex();
    }
    if (channelSettingsKeys.contains("ctcssOn")) {
        settings.m_ctcssOn = response.getNfmModSettings()->getCtcssOn() != 0;
    }
    if (channelSettingsKeys.contains("fmDeviation")) {
        settings.m_fmDeviation = response.getNfmModSettings()->getFmDeviation();
    }
    if (channelSettingsKeys.contains("inputFrequencyOffset")) {
        settings.m_inputFrequencyOffset = response.getNfmModSettings()->getInputFrequencyOffset();
    }
    if (channelSettingsKeys.contains("modAFInput")) {
        settings.m_modAFInput = (NFMModSettings::NFMModInputAF) response.getNfmModSettings()->getModAfInput();
    }
    if (channelSettingsKeys.contains("playLoop")) {
        settings.m_playLoop = response.getNfmModSettings()->getPlayLoop() != 0;
    }
    if (channelSettingsKeys.contains("rfBandwidth")) {
        settings.m_rfBandwidth = response.getNfmModSettings()->getRfBandwidth();
    }
    if (channelSettingsKeys.contains("rgbColor")) {
        settings.m_rgbColor = response.getNfmModSettings()->getRgbColor();
    }
    if (channelSettingsKeys.contains("title")) {
        settings.m_title = *response.getNfmModSettings()->getTitle();
    }
    if (channelSettingsKeys.contains("toneFrequency")) {
        settings.m_toneFrequency = response.getNfmModSettings()->getToneFrequency();
    }
    if (channelSettingsKeys.contains("volumeFactor")) {
        settings.m_volumeFactor = response.getNfmModSettings()->getVolumeFactor();
    }
    if (channelSettingsKeys.contains("useReverseAPI")) {
        settings.m_useReverseAPI = response.getNfmModSettings()->getUseReverseApi() != 0;
    }
    if (channelSettingsKeys.contains("reverseAPIAddress")) {
        settings.m_reverseAPIAddress = *response.getNfmModSettings()->getReverseApiAddress();
    }
    if (channelSettingsKeys.contains("reverseAPIPort")) {
        settings.m_reverseAPIPort = response.getNfmModSettings()->getReverseApiPort();
    }
    if (channelSettingsKeys.contains("reverseAPIDeviceIndex")) {
        settings.m_reverseAPIDeviceIndex = response.getNfmModSettings()->getReverseApiDeviceIndex();
    }
    if (channelSettingsKeys.contains("reverseAPIChannelIndex")) {
        settings.m_reverseAPIChannelIndex = response.getNfmModSettings()->getReverseApiChannelIndex();
    }
}

int NFMMod::webapiReportGet(
                SWGSDRangel::SWGChannelReport& response,
                QString& errorMessage)
{
    (void) errorMessage;
    response.setNfmModReport(new SWGSDRangel::SWGNFMModReport());
    response.getNfmModReport()->init();
    webapiFormatChannelReport(response);
    return 200;
}

void NFMMod::webapiFormatChannelSettings(SWGSDRangel::SWGChannelSettings& response, const NFMModSettings& settings)
{
    response.getNfmModSettings()->setAfBandwidth(settings.m_afBandwidth);
    response.getNfmModSettings()->setChannelMute(settings.m_channelMute ? 1 : 0);
    response.getNfmModSettings()->setCtcssIndex(settings.m_ctcssIndex);
    response.getNfmModSettings()->setCtcssOn(settings.m_ctcssOn ? 1 : 0);
    response.getNfmModSettings()->setFmDeviation(settings.m_fmDeviation);
    response.getNfmModSettings()->setInputFrequencyOffset(settings.m_inputFrequencyOffset);
    response.getNfmModSettings()->setModAfInput((int) settings.m_modAFInput);
    response.getNfmModSettings()->setPlayLoop(settings.m_playLoop ? 1 : 0);
    response.getNfmModSettings()->setRfBandwidth(settings.m_rfBandwidth);
    response.getNfmModSettings()->setRgbColor(settings.m_rgbColor);

    if (response.getNfmModSettings()->getTitle()) {
        *response.getNfmModSettings()->getTitle() = settings.m_title;
    } else {
        response.getNfmModSettings()->setTitle(new QString(settings.m_title));
    }

    response.getNfmModSettings()->setToneFrequency(settings.m_toneFrequency);
    response.getNfmModSettings()->setVolumeFactor(settings.m_volumeFactor);

    if (!response.getNfmModSettings()->getCwKeyer()) {
        response.getNfmModSettings()->setCwKeyer(new SWGSDRangel::SWGCWKeyerSettings);
    }

    if (response.getNfmModSettings()->getAudioDeviceName()) {
        *response.getNfmModSettings()->getAudioDeviceName() = settings.m_audioDeviceName;
    } else {
        response.getNfmModSettings()->setAudioDeviceName(new QString(settings.m_audioDeviceName));
    }

    response.getNfmModSettings()->setUseReverseApi(settings.m_useReverseAPI ? 1 : 0);

    if (response.getNfmModSettings()->getReverseApiAddress()) {
        *response.getNfmModSettings()->getReverseApiAddress() = settings.m_reverseAPIAddress;
    } else {
        response.getNfmModSettings()->setReverseApiAddress(new QString(settings.m_reverseAPIAddress));
    }

    response.getNfmModSettings()->setReverseApiPort(settings.m_reverseAPIPort);
    response.getNfmModSettings()->setReverseApiDeviceIndex(settings.m_reverseAPIDeviceIndex);
    response.getNfmModSettings()->setReverseApiChannelIndex(settings.m_reverseAPIChannelIndex);
}

void NFMMod::webapiFormatChannelReport(SWGSDRangel::SWGChannelReport& response)
{
    response.getNfmModReport()->setChannelPowerDb(CalcDb::dbPower(getMagSq()));
    response.getNfmModReport()->setAudioSampleRate(m_audioSampleRate);
    response.getNfmModReport()->setChannelSampleRate(m_outputSampleRate);
}

void NFMMod::webapiReverseSendSettings(QList<QString>& channelSettingsKeys, const NFMModSettings& settings, bool force)
{
    SWGSDRangel::SWGChannelSettings *swgChannelSettings = new SWGSDRangel::SWGChannelSettings();
    swgChannelSettings->setDirection(1); // single source (Tx)
    swgChannelSettings->setOriginatorChannelIndex(getIndexInDeviceSet());
    swgChannelSettings->setOriginatorDeviceSetIndex(getDeviceSetIndex());
    swgChannelSettings->setChannelType(new QString("NFMMod"));
    swgChannelSettings->setNfmModSettings(new SWGSDRangel::SWGNFMModSettings());
    SWGSDRangel::SWGNFMModSettings *swgNFMModSettings = swgChannelSettings->getNfmModSettings();

    // transfer data that has been modified. When force is on transfer all data except reverse API data

    if (channelSettingsKeys.contains("channelMute") || force) {
        swgNFMModSettings->setChannelMute(settings.m_channelMute ? 1 : 0);
    }
    if (channelSettingsKeys.contains("inputFrequencyOffset") || force) {
        swgNFMModSettings->setInputFrequencyOffset(settings.m_inputFrequencyOffset);
    }
    if (channelSettingsKeys.contains("modAFInput") || force) {
        swgNFMModSettings->setModAfInput((int) settings.m_modAFInput);
    }
    if (channelSettingsKeys.contains("audioDeviceName") || force) {
        swgNFMModSettings->setAudioDeviceName(new QString(settings.m_audioDeviceName));
    }
    if (channelSettingsKeys.contains("playLoop") || force) {
        swgNFMModSettings->setPlayLoop(settings.m_playLoop ? 1 : 0);
    }
    if (channelSettingsKeys.contains("afBandwidth") || force) {
        swgNFMModSettings->setAfBandwidth(settings.m_afBandwidth);
    }
    if (channelSettingsKeys.contains("fmDeviation") || force) {
        swgNFMModSettings->setFmDeviation(settings.m_fmDeviation);
    }
    if (channelSettingsKeys.contains("rfBandwidth") || force) {
        swgNFMModSettings->setRfBandwidth(settings.m_rfBandwidth);
    }
    if (channelSettingsKeys.contains("rgbColor") || force) {
        swgNFMModSettings->setRgbColor(settings.m_rgbColor);
    }
    if (channelSettingsKeys.contains("title") || force) {
        swgNFMModSettings->setTitle(new QString(settings.m_title));
    }
    if (channelSettingsKeys.contains("toneFrequency") || force) {
        swgNFMModSettings->setToneFrequency(settings.m_toneFrequency);
    }
    if (channelSettingsKeys.contains("volumeFactor") || force) {
        swgNFMModSettings->setVolumeFactor(settings.m_volumeFactor);
    }
    if (channelSettingsKeys.contains("ctcssOn") || force) {
        swgNFMModSettings->setCtcssOn(settings.m_ctcssOn ? 1 : 0);
    }
    if (channelSettingsKeys.contains("ctcssIndex") || force) {
        swgNFMModSettings->setCtcssIndex(settings.m_ctcssIndex);
    }

    if (force)
    {
        const CWKeyerSettings& cwKeyerSettings = m_cwKeyer.getSettings();
        swgNFMModSettings->setCwKeyer(new SWGSDRangel::SWGCWKeyerSettings());
        SWGSDRangel::SWGCWKeyerSettings *apiCwKeyerSettings = swgNFMModSettings->getCwKeyer();
        m_cwKeyer.webapiFormatChannelSettings(apiCwKeyerSettings, cwKeyerSettings);
    }

    QString channelSettingsURL = QString("http://%1:%2/sdrangel/deviceset/%3/channel/%4/settings")
            .arg(settings.m_reverseAPIAddress)
            .arg(settings.m_reverseAPIPort)
            .arg(settings.m_reverseAPIDeviceIndex)
            .arg(settings.m_reverseAPIChannelIndex);
    m_networkRequest.setUrl(QUrl(channelSettingsURL));
    m_networkRequest.setHeader(QNetworkRequest::ContentTypeHeader, "application/json");

    QBuffer *buffer=new QBuffer();
    buffer->open((QBuffer::ReadWrite));
    buffer->write(swgChannelSettings->asJson().toUtf8());
    buffer->seek(0);

    // Always use PATCH to avoid passing reverse API settings
    m_networkManager->sendCustomRequest(m_networkRequest, "PATCH", buffer);

    delete swgChannelSettings;
}

void NFMMod::webapiReverseSendCWSettings(const CWKeyerSettings& cwKeyerSettings)
{
    SWGSDRangel::SWGChannelSettings *swgChannelSettings = new SWGSDRangel::SWGChannelSettings();
    swgChannelSettings->setDirection(1); // single source (Tx)
    swgChannelSettings->setChannelType(new QString("NFMMod"));
    swgChannelSettings->setNfmModSettings(new SWGSDRangel::SWGNFMModSettings());
    SWGSDRangel::SWGNFMModSettings *swgNFModSettings = swgChannelSettings->getNfmModSettings();

    swgNFModSettings->setCwKeyer(new SWGSDRangel::SWGCWKeyerSettings());
    SWGSDRangel::SWGCWKeyerSettings *apiCwKeyerSettings = swgNFModSettings->getCwKeyer();
    m_cwKeyer.webapiFormatChannelSettings(apiCwKeyerSettings, cwKeyerSettings);

    QString channelSettingsURL = QString("http://%1:%2/sdrangel/deviceset/%3/channel/%4/settings")
            .arg(m_settings.m_reverseAPIAddress)
            .arg(m_settings.m_reverseAPIPort)
            .arg(m_settings.m_reverseAPIDeviceIndex)
            .arg(m_settings.m_reverseAPIChannelIndex);
    m_networkRequest.setUrl(QUrl(channelSettingsURL));
    m_networkRequest.setHeader(QNetworkRequest::ContentTypeHeader, "application/json");

    QBuffer *buffer=new QBuffer();
    buffer->open((QBuffer::ReadWrite));
    buffer->write(swgChannelSettings->asJson().toUtf8());
    buffer->seek(0);

    // Always use PATCH to avoid passing reverse API settings
    m_networkManager->sendCustomRequest(m_networkRequest, "PATCH", buffer);

    delete swgChannelSettings;
}

void NFMMod::networkManagerFinished(QNetworkReply *reply)
{
    QNetworkReply::NetworkError replyError = reply->error();

    if (replyError)
    {
        qWarning() << "NFMMod::networkManagerFinished:"
                << " error(" << (int) replyError
                << "): " << replyError
                << ": " << reply->errorString();
        return;
    }

    QString answer = reply->readAll();
    answer.chop(1); // remove last \n
    qDebug("NFMMod::networkManagerFinished: reply:\n%s", answer.toStdString().c_str());
}