Added new Broadcast FM demod. Copy of WFM for now

plugins/channel/CMakeLists.txt

@@ -2,6 +2,7 @@ project(demod)
 
 add_subdirectory(lora)
 add_subdirectory(am)
+add_subdirectory(bfm)
 add_subdirectory(nfm)
 add_subdirectory(ssb)
 add_subdirectory(tcpsrc)

plugins/channel/bfm/CMakeLists.txt

@@ -0,0 +1,46 @@
+project(bfm)
+
+set(bfm_SOURCES
+	bfmdemod.cpp
+	bfmdemodgui.cpp
+	bfmplugin.cpp
+)
+
+set(bfm_HEADERS
+	bfmdemod.h
+	bfmdemodgui.h
+	bfmplugin.h
+)
+
+set(bfm_FORMS
+	bfmdemodgui.ui
+)
+
+include_directories(
+	.
+	${CMAKE_CURRENT_BINARY_DIR}
+	${CMAKE_SOURCE_DIR}/include
+	${CMAKE_SOURCE_DIR}/include-gpl
+	${OPENGL_INCLUDE_DIR}
+)
+
+#include(${QT_USE_FILE})
+add_definitions(${QT_DEFINITIONS})
+add_definitions(-DQT_PLUGIN)
+add_definitions(-DQT_SHARED)
+
+qt5_wrap_ui(bfm_FORMS_HEADERS ${bfm_FORMS})
+
+add_library(demodbfm SHARED
+	${bfm_SOURCES}
+	${bfm_HEADERS_MOC}
+	${bfm_FORMS_HEADERS}
+)
+
+target_link_libraries(demodbfm
+	${QT_LIBRARIES}
+	${OPENGL_LIBRARIES}
+	sdrbase
+)
+
+qt5_use_modules(demodbfm Core Widgets OpenGL Multimedia)

plugins/channel/bfm/bfmdemod.cpp

@@ -0,0 +1,284 @@
+///////////////////////////////////////////////////////////////////////////////////
+// Copyright (C) 2012 maintech GmbH, Otto-Hahn-Str. 15, 97204 Hoechberg, Germany //
+// written by Christian Daniel                                                   //
+//                                                                               //
+// 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                  //
+//                                                                               //
+// 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 <stdio.h>
+#include <complex.h>
+#include "audio/audiooutput.h"
+#include "dsp/dspengine.h"
+#include "dsp/channelizer.h"
+#include "dsp/pidcontroller.h"
+
+#include "bfmdemod.h"
+
+MESSAGE_CLASS_DEFINITION(BFMDemod::MsgConfigureBFMDemod, Message)
+
+BFMDemod::BFMDemod(SampleSink* sampleSink) :
+	m_sampleSink(sampleSink),
+	m_audioFifo(4, 250000),
+	m_settingsMutex(QMutex::Recursive)
+{
+	setObjectName("BFMDemod");
+
+	m_config.m_inputSampleRate = 384000;
+	m_config.m_inputFrequencyOffset = 0;
+	m_config.m_rfBandwidth = 180000;
+	m_config.m_afBandwidth = 15000;
+	m_config.m_squelch = -60.0;
+	m_config.m_volume = 2.0;
+	m_config.m_audioSampleRate = DSPEngine::instance()->getAudioSampleRate();
+	m_rfFilter = new fftfilt(-50000.0 / 384000.0, 50000.0 / 384000.0, rfFilterFftLength);
+
+	apply();
+
+	m_audioBuffer.resize(16384);
+	m_audioBufferFill = 0;
+
+	m_movingAverage.resize(16, 0);
+
+	DSPEngine::instance()->addAudioSink(&m_audioFifo);
+}
+
+BFMDemod::~BFMDemod()
+{
+	if (m_rfFilter)
+	{
+		delete m_rfFilter;
+	}
+
+	DSPEngine::instance()->removeAudioSink(&m_audioFifo);
+}
+
+void BFMDemod::configure(MessageQueue* messageQueue, Real rfBandwidth, Real afBandwidth, Real volume, Real squelch)
+{
+	Message* cmd = MsgConfigureBFMDemod::create(rfBandwidth, afBandwidth, volume, squelch);
+	messageQueue->push(cmd);
+}
+
+void BFMDemod::feed(const SampleVector::const_iterator& begin, const SampleVector::const_iterator& end, bool firstOfBurst)
+{
+	Complex ci;
+	fftfilt::cmplx *rf;
+	int rf_out;
+	Real msq, demod;
+
+	m_settingsMutex.lock();
+
+	for (SampleVector::const_iterator it = begin; it != end; ++it)
+	{
+		Complex c(it->real() / 32768.0f, it->imag() / 32768.0f);
+		c *= m_nco.nextIQ();
+
+		rf_out = m_rfFilter->runFilt(c, &rf); // filter RF before demod
+
+		for (int i =0 ; i  <rf_out; i++)
+		{
+			msq = rf[i].real()*rf[i].real() + rf[i].imag()*rf[i].imag();
+
+			m_movingAverage.feed(msq);
+
+			if(m_movingAverage.average() >= m_squelchLevel)
+				m_squelchState = m_running.m_rfBandwidth / 20; // decay rate
+
+			if(m_squelchState > 0)
+			{
+				m_squelchState--;
+
+				// Alternative without atan
+				// http://www.embedded.com/design/configurable-systems/4212086/DSP-Tricks--Frequency-demodulation-algorithms-
+				// in addition it needs scaling by instantaneous magnitude squared and volume (0..10) adjustment factor
+				Real ip = rf[i].real() - m_m2Sample.real();
+				Real qp = rf[i].imag() - m_m2Sample.imag();
+				Real h1 = m_m1Sample.real() * qp;
+				Real h2 = m_m1Sample.imag() * ip;
+				demod = (h1 - h2) / (msq * 10.0);
+			}
+			else
+			{
+				demod = 0;
+			}
+
+			m_m2Sample = m_m1Sample;
+			m_m1Sample = rf[i];
+
+			Complex e(demod, 0);
+
+			if(m_interpolator.interpolate(&m_interpolatorDistanceRemain, e, &ci))
+			{
+				quint16 sample = (qint16)(ci.real() * 3000 * m_running.m_volume);
+				m_sampleBuffer.push_back(Sample(sample, sample));
+				m_audioBuffer[m_audioBufferFill].l = sample;
+				m_audioBuffer[m_audioBufferFill].r = sample;
+				++m_audioBufferFill;
+
+				if(m_audioBufferFill >= m_audioBuffer.size())
+				{
+					uint res = m_audioFifo.write((const quint8*)&m_audioBuffer[0], m_audioBufferFill, 1);
+
+					if(res != m_audioBufferFill)
+					{
+						qDebug("BFMDemod::feed: %u/%u audio samples written", res, m_audioBufferFill);
+					}
+
+					m_audioBufferFill = 0;
+				}
+
+				m_interpolatorDistanceRemain += m_interpolatorDistance;
+			}
+		}
+	}
+
+	if(m_audioBufferFill > 0)
+	{
+		uint res = m_audioFifo.write((const quint8*)&m_audioBuffer[0], m_audioBufferFill, 1);
+
+		if(res != m_audioBufferFill)
+		{
+			qDebug("BFMDemod::feed: %u/%u tail samples written", res, m_audioBufferFill);
+		}
+
+		m_audioBufferFill = 0;
+	}
+
+	if(m_sampleSink != 0)
+	{
+		m_sampleSink->feed(m_sampleBuffer.begin(), m_sampleBuffer.end(), false);
+	}
+
+	m_sampleBuffer.clear();
+
+	m_settingsMutex.unlock();
+}
+
+void BFMDemod::start()
+{
+	m_squelchState = 0;
+	m_audioFifo.clear();
+	m_m1Sample = 0;
+}
+
+void BFMDemod::stop()
+{
+}
+
+bool BFMDemod::handleMessage(const Message& cmd)
+{
+	qDebug() << "BFMDemod::handleMessage";
+
+	if (Channelizer::MsgChannelizerNotification::match(cmd))
+	{
+		Channelizer::MsgChannelizerNotification& notif = (Channelizer::MsgChannelizerNotification&) cmd;
+
+		m_config.m_inputSampleRate = notif.getSampleRate();
+		m_config.m_inputFrequencyOffset = notif.getFrequencyOffset();
+
+		apply();
+
+		qDebug() << "BFMDemod::handleMessage: MsgChannelizerNotification: m_inputSampleRate: " << m_config.m_inputSampleRate
+				<< " m_inputFrequencyOffset: " << m_config.m_inputFrequencyOffset;
+
+		return true;
+	}
+	else if (MsgConfigureBFMDemod::match(cmd))
+	{
+		MsgConfigureBFMDemod& cfg = (MsgConfigureBFMDemod&) cmd;
+
+		m_config.m_rfBandwidth = cfg.getRFBandwidth();
+		m_config.m_afBandwidth = cfg.getAFBandwidth();
+		m_config.m_volume = cfg.getVolume();
+		m_config.m_squelch = cfg.getSquelch();
+
+		apply();
+
+		qDebug() << "BFMDemod::handleMessage: MsgConfigureBFMDemod: m_rfBandwidth: " << m_config.m_rfBandwidth
+				<< " m_afBandwidth: " << m_config.m_afBandwidth
+				<< " m_volume: " << m_config.m_volume
+				<< " m_squelch: " << m_config.m_squelch;
+
+		return true;
+	}
+	else
+	{
+		if (m_sampleSink != 0)
+		{
+		    return m_sampleSink->handleMessage(cmd);
+		}
+		else
+		{
+			return false;
+		}
+	}
+}
+
+void BFMDemod::apply()
+{
+
+	if((m_config.m_inputFrequencyOffset != m_running.m_inputFrequencyOffset) ||
+		(m_config.m_inputSampleRate != m_running.m_inputSampleRate))
+	{
+		qDebug() << "BFMDemod::handleMessage: m_nco.setFreq";
+		m_nco.setFreq(-m_config.m_inputFrequencyOffset, m_config.m_inputSampleRate);
+	}
+
+	if((m_config.m_inputSampleRate != m_running.m_inputSampleRate) ||
+		(m_config.m_afBandwidth != m_running.m_afBandwidth))
+	{
+		m_settingsMutex.lock();
+		qDebug() << "BFMDemod::handleMessage: m_interpolator.create";
+		m_interpolator.create(16, m_config.m_inputSampleRate, m_config.m_afBandwidth);
+		m_interpolatorDistanceRemain = (Real) m_config.m_inputSampleRate / m_config.m_audioSampleRate;
+		m_interpolatorDistance =  (Real) m_config.m_inputSampleRate / (Real) m_config.m_audioSampleRate;
+		m_settingsMutex.unlock();
+	}
+
+	if((m_config.m_inputSampleRate != m_running.m_inputSampleRate) ||
+		(m_config.m_rfBandwidth != m_running.m_rfBandwidth) ||
+		(m_config.m_inputFrequencyOffset != m_running.m_inputFrequencyOffset))
+	{
+		m_settingsMutex.lock();
+		qDebug() << "BFMDemod::handleMessage: m_rfFilter->create_filter";
+		Real lowCut = -(m_config.m_rfBandwidth / 2.0) / m_config.m_inputSampleRate;
+		Real hiCut  = (m_config.m_rfBandwidth / 2.0) / m_config.m_inputSampleRate;
+		m_rfFilter->create_filter(lowCut, hiCut);
+		m_settingsMutex.unlock();
+	}
+
+	if((m_config.m_afBandwidth != m_running.m_afBandwidth) ||
+		(m_config.m_audioSampleRate != m_running.m_audioSampleRate))
+	{
+		m_settingsMutex.lock();
+		qDebug() << "BFMDemod::handleMessage: m_lowpass.create";
+		m_lowpass.create(21, m_config.m_audioSampleRate, m_config.m_afBandwidth);
+		m_settingsMutex.unlock();
+	}
+
+	if(m_config.m_squelch != m_running.m_squelch) {
+		qDebug() << "BFMDemod::handleMessage: set m_squelchLevel";
+		m_squelchLevel = pow(10.0, m_config.m_squelch / 20.0);
+		m_squelchLevel *= m_squelchLevel;
+	}
+
+	m_running.m_inputSampleRate = m_config.m_inputSampleRate;
+	m_running.m_inputFrequencyOffset = m_config.m_inputFrequencyOffset;
+	m_running.m_rfBandwidth = m_config.m_rfBandwidth;
+	m_running.m_afBandwidth = m_config.m_afBandwidth;
+	m_running.m_squelch = m_config.m_squelch;
+	m_running.m_volume = m_config.m_volume;
+	m_running.m_audioSampleRate = m_config.m_audioSampleRate;
+
+}

plugins/channel/bfm/bfmdemod.h

@@ -0,0 +1,138 @@
+///////////////////////////////////////////////////////////////////////////////////
+// Copyright (C) 2012 maintech GmbH, Otto-Hahn-Str. 15, 97204 Hoechberg, Germany //
+// written by Christian Daniel                                                   //
+//                                                                               //
+// 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                  //
+//                                                                               //
+// 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/>.          //
+///////////////////////////////////////////////////////////////////////////////////
+
+#ifndef INCLUDE_BFMDEMOD_H
+#define INCLUDE_BFMDEMOD_H
+
+#include <QMutex>
+#include <vector>
+#include "dsp/samplesink.h"
+#include "dsp/nco.h"
+#include "dsp/interpolator.h"
+#include "dsp/lowpass.h"
+#include "dsp/movingaverage.h"
+#include "dsp/fftfilt.h"
+#include "audio/audiofifo.h"
+#include "util/message.h"
+
+#define rfFilterFftLength 1024
+
+class BFMDemod : public SampleSink {
+public:
+	BFMDemod(SampleSink* sampleSink);
+	virtual ~BFMDemod();
+
+	void configure(MessageQueue* messageQueue, Real rfBandwidth, Real afBandwidth, Real volume, Real squelch);
+
+	virtual void feed(const SampleVector::const_iterator& begin, const SampleVector::const_iterator& end, bool po);
+	virtual void start();
+	virtual void stop();
+	virtual bool handleMessage(const Message& cmd);
+
+	Real getMagSq() const { return m_movingAverage.average(); }
+
+private:
+	class MsgConfigureBFMDemod : public Message {
+		MESSAGE_CLASS_DECLARATION
+
+	public:
+		Real getRFBandwidth() const { return m_rfBandwidth; }
+		Real getAFBandwidth() const { return m_afBandwidth; }
+		Real getVolume() const { return m_volume; }
+		Real getSquelch() const { return m_squelch; }
+
+		static MsgConfigureBFMDemod* create(Real rfBandwidth, Real afBandwidth, Real volume, Real squelch)
+		{
+			return new MsgConfigureBFMDemod(rfBandwidth, afBandwidth, volume, squelch);
+		}
+
+	private:
+		Real m_rfBandwidth;
+		Real m_afBandwidth;
+		Real m_volume;
+		Real m_squelch;
+
+		MsgConfigureBFMDemod(Real rfBandwidth, Real afBandwidth, Real volume, Real squelch) :
+			Message(),
+			m_rfBandwidth(rfBandwidth),
+			m_afBandwidth(afBandwidth),
+			m_volume(volume),
+			m_squelch(squelch)
+		{ }
+	};
+
+	struct AudioSample {
+		qint16 l;
+		qint16 r;
+	};
+	typedef std::vector<AudioSample> AudioVector;
+
+	enum RateState {
+		RSInitialFill,
+		RSRunning
+	};
+
+	struct Config {
+		int m_inputSampleRate;
+		qint64 m_inputFrequencyOffset;
+		Real m_rfBandwidth;
+		Real m_afBandwidth;
+		Real m_squelch;
+		Real m_volume;
+		quint32 m_audioSampleRate;
+
+		Config() :
+			m_inputSampleRate(-1),
+			m_inputFrequencyOffset(0),
+			m_rfBandwidth(-1),
+			m_afBandwidth(-1),
+			m_squelch(0),
+			m_volume(0),
+			m_audioSampleRate(0)
+		{ }
+	};
+
+	Config m_config;
+	Config m_running;
+
+	NCO m_nco;
+	Interpolator m_interpolator; //!< Interpolator between sample rate sent from DSP engine and requested RF bandwidth (rational)
+	Real m_interpolatorDistance;
+	Real m_interpolatorDistanceRemain;
+	Lowpass<Real> m_lowpass;
+	fftfilt* m_rfFilter;
+
+	Real m_squelchLevel;
+	int m_squelchState;
+
+	Real m_lastArgument;
+	Complex m_m1Sample; //!< x^-1 sample
+	Complex m_m2Sample; //!< x^-1 sample
+	MovingAverage<Real> m_movingAverage;
+
+	AudioVector m_audioBuffer;
+	uint m_audioBufferFill;
+
+	SampleSink* m_sampleSink;
+	AudioFifo m_audioFifo;
+	SampleVector m_sampleBuffer;
+	QMutex m_settingsMutex;
+
+	void apply();
+};
+
+#endif // INCLUDE_BFMDEMOD_H

plugins/channel/bfm/bfmdemodgui.cpp

@@ -0,0 +1,302 @@
+#include <QDockWidget>
+#include <QMainWindow>
+#include <QDebug>
+#include "dsp/threadedsamplesink.h"
+#include "dsp/channelizer.h"
+#include "dsp/dspengine.h"
+#include "gui/glspectrum.h"
+#include "plugin/pluginapi.h"
+#include "util/simpleserializer.h"
+#include "util/db.h"
+#include "gui/basicchannelsettingswidget.h"
+#include "mainwindow.h"
+
+#include "bfmdemodgui.h"
+
+#include "ui_bfmdemodgui.h"
+#include "bfmdemod.h"
+
+const int BFMDemodGUI::m_rfBW[] = {
+	48000, 80000, 120000, 140000, 160000, 180000, 200000, 220000, 250000
+};
+
+int requiredBW(int rfBW)
+{
+	if (rfBW <= 48000)
+		return 48000;
+	else if (rfBW < 100000)
+		return 96000;
+	else
+		return 384000;
+}
+
+BFMDemodGUI* BFMDemodGUI::create(PluginAPI* pluginAPI)
+{
+	BFMDemodGUI* gui = new BFMDemodGUI(pluginAPI);
+	return gui;
+}
+
+void BFMDemodGUI::destroy()
+{
+	delete this;
+}
+
+void BFMDemodGUI::setName(const QString& name)
+{
+	setObjectName(name);
+}
+
+QString BFMDemodGUI::getName() const
+{
+	return objectName();
+}
+
+qint64 BFMDemodGUI::getCenterFrequency() const
+{
+	return m_channelMarker.getCenterFrequency();
+}
+
+void BFMDemodGUI::setCenterFrequency(qint64 centerFrequency)
+{
+	m_channelMarker.setCenterFrequency(centerFrequency);
+	applySettings();
+}
+
+void BFMDemodGUI::resetToDefaults()
+{
+	blockApplySettings(true);
+
+	ui->rfBW->setValue(4);
+	ui->afBW->setValue(3);
+	ui->volume->setValue(20);
+	ui->squelch->setValue(-40);
+	ui->deltaFrequency->setValue(0);
+
+	blockApplySettings(false);
+	applySettings();
+}
+
+QByteArray BFMDemodGUI::serialize() const
+{
+	SimpleSerializer s(1);
+	s.writeS32(1, m_channelMarker.getCenterFrequency());
+	s.writeS32(2, ui->rfBW->value());
+	s.writeS32(3, ui->afBW->value());
+	s.writeS32(4, ui->volume->value());
+	s.writeS32(5, ui->squelch->value());
+	s.writeU32(7, m_channelMarker.getColor().rgb());
+	return s.final();
+}
+
+bool BFMDemodGUI::deserialize(const QByteArray& data)
+{
+	SimpleDeserializer d(data);
+
+	if (!d.isValid())
+	{
+		resetToDefaults();
+		return false;
+	}
+
+	if (d.getVersion() == 1)
+	{
+		QByteArray bytetmp;
+		quint32 u32tmp;
+		qint32 tmp;
+
+		blockApplySettings(true);
+	    m_channelMarker.blockSignals(true);
+
+		d.readS32(1, &tmp, 0);
+		m_channelMarker.setCenterFrequency(tmp);
+		d.readS32(2, &tmp, 4);
+		ui->rfBW->setValue(tmp);
+		d.readS32(3, &tmp, 3);
+		ui->afBW->setValue(tmp);
+		d.readS32(4, &tmp, 20);
+		ui->volume->setValue(tmp);
+		d.readS32(5, &tmp, -40);
+		ui->squelch->setValue(tmp);
+
+		if(d.readU32(7, &u32tmp))
+		{
+			m_channelMarker.setColor(u32tmp);
+		}
+
+		blockApplySettings(false);
+	    m_channelMarker.blockSignals(false);
+
+		applySettings();
+		return true;
+	}
+	else
+	{
+		resetToDefaults();
+		return false;
+	}
+}
+
+bool BFMDemodGUI::handleMessage(const Message& message)
+{
+	return false;
+}
+
+void BFMDemodGUI::viewChanged()
+{
+	applySettings();
+}
+
+void BFMDemodGUI::on_deltaMinus_toggled(bool minus)
+{
+	int deltaFrequency = m_channelMarker.getCenterFrequency();
+	bool minusDelta = (deltaFrequency < 0);
+
+	if (minus ^ minusDelta) // sign change
+	{
+		m_channelMarker.setCenterFrequency(-deltaFrequency);
+	}
+}
+
+void BFMDemodGUI::on_deltaFrequency_changed(quint64 value)
+{
+	if (ui->deltaMinus->isChecked())
+	{
+		m_channelMarker.setCenterFrequency(-value);
+	}
+	else
+	{
+		m_channelMarker.setCenterFrequency(value);
+	}
+}
+
+void BFMDemodGUI::on_rfBW_valueChanged(int value)
+{
+	ui->rfBWText->setText(QString("%1 kHz").arg(m_rfBW[value] / 1000.0));
+	m_channelMarker.setBandwidth(m_rfBW[value]);
+	applySettings();
+}
+
+void BFMDemodGUI::on_afBW_valueChanged(int value)
+{
+	ui->afBWText->setText(QString("%1 kHz").arg(value));
+	applySettings();
+}
+
+void BFMDemodGUI::on_volume_valueChanged(int value)
+{
+	ui->volumeText->setText(QString("%1").arg(value / 10.0, 0, 'f', 1));
+	applySettings();
+}
+
+void BFMDemodGUI::on_squelch_valueChanged(int value)
+{
+	ui->squelchText->setText(QString("%1 dB").arg(value));
+	applySettings();
+}
+
+
+void BFMDemodGUI::onWidgetRolled(QWidget* widget, bool rollDown)
+{
+}
+
+void BFMDemodGUI::onMenuDoubleClicked()
+{
+	if(!m_basicSettingsShown)
+	{
+		m_basicSettingsShown = true;
+		BasicChannelSettingsWidget* bcsw = new BasicChannelSettingsWidget(&m_channelMarker, this);
+		bcsw->show();
+	}
+}
+
+BFMDemodGUI::BFMDemodGUI(PluginAPI* pluginAPI, QWidget* parent) :
+	RollupWidget(parent),
+	ui(new Ui::BFMDemodGUI),
+	m_pluginAPI(pluginAPI),
+	m_channelMarker(this),
+	m_basicSettingsShown(false),
+	m_channelPowerDbAvg(20,0)
+{
+	ui->setupUi(this);
+	ui->deltaFrequency->setColorMapper(ColorMapper(ColorMapper::ReverseGold));
+	ui->deltaFrequency->setValueRange(7, 0U, 9999999U);
+
+	setAttribute(Qt::WA_DeleteOnClose, true);
+	connect(this, SIGNAL(widgetRolled(QWidget*,bool)), this, SLOT(onWidgetRolled(QWidget*,bool)));
+	connect(this, SIGNAL(menuDoubleClickEvent()), this, SLOT(onMenuDoubleClicked()));
+
+	m_wfmDemod = new BFMDemod(0);
+	m_channelizer = new Channelizer(m_wfmDemod);
+	m_threadedChannelizer = new ThreadedSampleSink(m_channelizer, this);
+	DSPEngine::instance()->addThreadedSink(m_threadedChannelizer);
+
+	connect(&m_pluginAPI->getMainWindow()->getMasterTimer(), SIGNAL(timeout()), this, SLOT(tick()));
+
+	//m_channelMarker = new ChannelMarker(this);
+	m_channelMarker.setColor(Qt::blue);
+	m_channelMarker.setBandwidth(12500);
+	m_channelMarker.setCenterFrequency(0);
+	m_channelMarker.setVisible(true);
+	connect(&m_channelMarker, SIGNAL(changed()), this, SLOT(viewChanged()));
+	m_pluginAPI->addChannelMarker(&m_channelMarker);
+
+	applySettings();
+}
+
+BFMDemodGUI::~BFMDemodGUI()
+{
+	m_pluginAPI->removeChannelInstance(this);
+	DSPEngine::instance()->removeThreadedSink(m_threadedChannelizer);
+	delete m_threadedChannelizer;
+	delete m_channelizer;
+	delete m_wfmDemod;
+	//delete m_channelMarker;
+	delete ui;
+}
+
+void BFMDemodGUI::blockApplySettings(bool block)
+{
+    m_doApplySettings = !block;
+}
+
+void BFMDemodGUI::applySettings()
+{
+	if (m_doApplySettings)
+	{
+		setTitleColor(m_channelMarker.getColor());
+
+		m_channelizer->configure(m_channelizer->getInputMessageQueue(),
+			requiredBW(m_rfBW[ui->rfBW->value()]), // TODO: this is where requested sample rate is specified
+			m_channelMarker.getCenterFrequency());
+
+		ui->deltaFrequency->setValue(abs(m_channelMarker.getCenterFrequency()));
+		ui->deltaMinus->setChecked(m_channelMarker.getCenterFrequency() < 0);
+
+		m_wfmDemod->configure(m_wfmDemod->getInputMessageQueue(),
+			m_rfBW[ui->rfBW->value()],
+			ui->afBW->value() * 1000.0,
+			ui->volume->value() / 10.0,
+			ui->squelch->value());
+	}
+}
+
+void BFMDemodGUI::leaveEvent(QEvent*)
+{
+	blockApplySettings(true);
+	m_channelMarker.setHighlighted(false);
+	blockApplySettings(false);
+}
+
+void BFMDemodGUI::enterEvent(QEvent*)
+{
+	blockApplySettings(true);
+	m_channelMarker.setHighlighted(true);
+	blockApplySettings(false);
+}
+
+void BFMDemodGUI::tick()
+{
+	Real powDb = CalcDb::dbPower(m_wfmDemod->getMagSq());
+	m_channelPowerDbAvg.feed(powDb);
+	ui->channelPower->setText(QString::number(m_channelPowerDbAvg.average(), 'f', 1));
+}

plugins/channel/bfm/bfmdemodgui.h

@@ -0,0 +1,73 @@
+#ifndef INCLUDE_BFMDEMODGUI_H
+#define INCLUDE_BFMDEMODGUI_H
+
+#include "gui/rollupwidget.h"
+#include "plugin/plugingui.h"
+#include "dsp/channelmarker.h"
+#include "dsp/movingaverage.h"
+
+class PluginAPI;
+
+class ThreadedSampleSink;
+class Channelizer;
+class BFMDemod;
+
+namespace Ui {
+	class BFMDemodGUI;
+}
+
+class BFMDemodGUI : public RollupWidget, public PluginGUI {
+	Q_OBJECT
+
+public:
+	static BFMDemodGUI* create(PluginAPI* pluginAPI);
+	void destroy();
+
+	void setName(const QString& name);
+	QString getName() const;
+	virtual qint64 getCenterFrequency() const;
+	virtual void setCenterFrequency(qint64 centerFrequency);
+
+	void resetToDefaults();
+	QByteArray serialize() const;
+	bool deserialize(const QByteArray& data);
+
+	virtual bool handleMessage(const Message& message);
+
+private slots:
+	void viewChanged();
+	void on_deltaFrequency_changed(quint64 value);
+	void on_deltaMinus_toggled(bool minus);
+	void on_rfBW_valueChanged(int value);
+	void on_afBW_valueChanged(int value);
+	void on_volume_valueChanged(int value);
+	void on_squelch_valueChanged(int value);
+	void onWidgetRolled(QWidget* widget, bool rollDown);
+	void onMenuDoubleClicked();
+	void tick();
+
+private:
+	Ui::BFMDemodGUI* ui;
+	PluginAPI* m_pluginAPI;
+	ChannelMarker m_channelMarker;
+	bool m_basicSettingsShown;
+	bool m_doApplySettings;
+
+	ThreadedSampleSink* m_threadedChannelizer;
+	Channelizer* m_channelizer;
+	BFMDemod* m_wfmDemod;
+	MovingAverage<Real> m_channelPowerDbAvg;
+
+	static const int m_rfBW[];
+
+	explicit BFMDemodGUI(PluginAPI* pluginAPI, QWidget* parent = NULL);
+	virtual ~BFMDemodGUI();
+
+    void blockApplySettings(bool block);
+	void applySettings();
+
+	void leaveEvent(QEvent*);
+	void enterEvent(QEvent*);
+};
+
+#endif // INCLUDE_BFMDEMODGUI_H

plugins/channel/bfm/bfmdemodgui.ui

@@ -0,0 +1,336 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>BFMDemodGUI</class>
+ <widget class="RollupWidget" name="BFMDemodGUI">
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>302</width>
+    <height>373</height>
+   </rect>
+  </property>
+  <property name="windowTitle">
+   <string>Broadcast FM Demod</string>
+  </property>
+  <widget class="QWidget" name="settingsContainer" native="true">
+   <property name="geometry">
+    <rect>
+     <x>20</x>
+     <y>20</y>
+     <width>235</width>
+     <height>121</height>
+    </rect>
+   </property>
+   <property name="windowTitle">
+    <string>Settings</string>
+   </property>
+   <layout class="QVBoxLayout" name="verticalLayout">
+    <property name="spacing">
+     <number>3</number>
+    </property>
+    <property name="leftMargin">
+     <number>2</number>
+    </property>
+    <property name="topMargin">
+     <number>2</number>
+    </property>
+    <property name="rightMargin">
+     <number>2</number>
+    </property>
+    <property name="bottomMargin">
+     <number>2</number>
+    </property>
+    <item>
+     <layout class="QHBoxLayout" name="deltaFreqPowLayout">
+      <item>
+       <layout class="QHBoxLayout" name="deltaFreqiencyLayout">
+        <item>
+         <widget class="QToolButton" name="deltaMinus">
+          <property name="text">
+           <string>...</string>
+          </property>
+          <property name="icon">
+           <iconset>
+            <selectedoff>:/plus.png</selectedoff>
+            <selectedon>:/minus.png</selectedon>
+           </iconset>
+          </property>
+          <property name="checkable">
+           <bool>true</bool>
+          </property>
+         </widget>
+        </item>
+        <item>
+         <widget class="ValueDial" name="deltaFrequency" native="true">
+          <property name="sizePolicy">
+           <sizepolicy hsizetype="Maximum" vsizetype="Maximum">
+            <horstretch>0</horstretch>
+            <verstretch>0</verstretch>
+           </sizepolicy>
+          </property>
+          <property name="minimumSize">
+           <size>
+            <width>32</width>
+            <height>16</height>
+           </size>
+          </property>
+          <property name="font">
+           <font>
+            <family>Monospace</family>
+            <pointsize>12</pointsize>
+           </font>
+          </property>
+          <property name="cursor">
+           <cursorShape>SizeVerCursor</cursorShape>
+          </property>
+          <property name="focusPolicy">
+           <enum>Qt::StrongFocus</enum>
+          </property>
+          <property name="toolTip">
+           <string>Demod shift frequency from center in Hz</string>
+          </property>
+         </widget>
+        </item>
+        <item>
+         <widget class="QLabel" name="deltaUnits">
+          <property name="text">
+           <string>Hz </string>
+          </property>
+         </widget>
+        </item>
+       </layout>
+      </item>
+      <item>
+       <spacer name="horizontalSpacer">
+        <property name="orientation">
+         <enum>Qt::Horizontal</enum>
+        </property>
+        <property name="sizeHint" stdset="0">
+         <size>
+          <width>40</width>
+          <height>20</height>
+         </size>
+        </property>
+       </spacer>
+      </item>
+      <item>
+       <layout class="QHBoxLayout" name="channelPowerLayout">
+        <item>
+         <widget class="QLabel" name="channelPower">
+          <property name="toolTip">
+           <string>Channel power</string>
+          </property>
+          <property name="layoutDirection">
+           <enum>Qt::RightToLeft</enum>
+          </property>
+          <property name="text">
+           <string>0.0</string>
+          </property>
+         </widget>
+        </item>
+        <item>
+         <widget class="QLabel" name="channelPowerUnits">
+          <property name="text">
+           <string> dB</string>
+          </property>
+         </widget>
+        </item>
+       </layout>
+      </item>
+     </layout>
+    </item>
+    <item>
+     <layout class="QHBoxLayout" name="rfBandwidthLayout">
+      <item>
+       <widget class="QLabel" name="label">
+        <property name="text">
+         <string>RF BW</string>
+        </property>
+       </widget>
+      </item>
+      <item>
+       <widget class="QSlider" name="rfBW">
+        <property name="maximum">
+         <number>8</number>
+        </property>
+        <property name="pageStep">
+         <number>1</number>
+        </property>
+        <property name="value">
+         <number>4</number>
+        </property>
+        <property name="orientation">
+         <enum>Qt::Horizontal</enum>
+        </property>
+       </widget>
+      </item>
+      <item>
+       <widget class="QLabel" name="rfBWText">
+        <property name="minimumSize">
+         <size>
+          <width>50</width>
+          <height>0</height>
+         </size>
+        </property>
+        <property name="text">
+         <string>12.5kHz</string>
+        </property>
+        <property name="alignment">
+         <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+        </property>
+       </widget>
+      </item>
+     </layout>
+    </item>
+    <item>
+     <layout class="QHBoxLayout" name="afBandwidthLayout">
+      <item>
+       <widget class="QLabel" name="label_2">
+        <property name="text">
+         <string>AF BW</string>
+        </property>
+       </widget>
+      </item>
+      <item>
+       <widget class="QSlider" name="afBW">
+        <property name="minimum">
+         <number>1</number>
+        </property>
+        <property name="maximum">
+         <number>20</number>
+        </property>
+        <property name="pageStep">
+         <number>1</number>
+        </property>
+        <property name="value">
+         <number>3</number>
+        </property>
+        <property name="orientation">
+         <enum>Qt::Horizontal</enum>
+        </property>
+       </widget>
+      </item>
+      <item>
+       <widget class="QLabel" name="afBWText">
+        <property name="minimumSize">
+         <size>
+          <width>50</width>
+          <height>0</height>
+         </size>
+        </property>
+        <property name="text">
+         <string>3 kHz</string>
+        </property>
+        <property name="alignment">
+         <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+        </property>
+       </widget>
+      </item>
+     </layout>
+    </item>
+    <item>
+     <layout class="QHBoxLayout" name="volumeLayout">
+      <item>
+       <widget class="QLabel" name="label_3">
+        <property name="text">
+         <string>Vol</string>
+        </property>
+       </widget>
+      </item>
+      <item>
+       <widget class="QSlider" name="volume">
+        <property name="maximum">
+         <number>100</number>
+        </property>
+        <property name="value">
+         <number>20</number>
+        </property>
+        <property name="orientation">
+         <enum>Qt::Horizontal</enum>
+        </property>
+       </widget>
+      </item>
+      <item>
+       <widget class="QLabel" name="volumeText">
+        <property name="minimumSize">
+         <size>
+          <width>50</width>
+          <height>0</height>
+         </size>
+        </property>
+        <property name="text">
+         <string>2.0</string>
+        </property>
+        <property name="alignment">
+         <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+        </property>
+       </widget>
+      </item>
+     </layout>
+    </item>
+    <item>
+     <layout class="QHBoxLayout" name="squelchLayout">
+      <item>
+       <widget class="QLabel" name="label_4">
+        <property name="text">
+         <string>Sq</string>
+        </property>
+       </widget>
+      </item>
+      <item>
+       <widget class="QSlider" name="squelch">
+        <property name="minimum">
+         <number>-100</number>
+        </property>
+        <property name="maximum">
+         <number>0</number>
+        </property>
+        <property name="value">
+         <number>-40</number>
+        </property>
+        <property name="orientation">
+         <enum>Qt::Horizontal</enum>
+        </property>
+       </widget>
+      </item>
+      <item>
+       <widget class="QLabel" name="squelchText">
+        <property name="minimumSize">
+         <size>
+          <width>50</width>
+          <height>0</height>
+         </size>
+        </property>
+        <property name="text">
+         <string>-40dB</string>
+        </property>
+        <property name="alignment">
+         <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+        </property>
+       </widget>
+      </item>
+     </layout>
+    </item>
+   </layout>
+  </widget>
+ </widget>
+ <customwidgets>
+  <customwidget>
+   <class>RollupWidget</class>
+   <extends>QWidget</extends>
+   <header>gui/rollupwidget.h</header>
+   <container>1</container>
+  </customwidget>
+  <customwidget>
+   <class>ValueDial</class>
+   <extends>QWidget</extends>
+   <header>gui/valuedial.h</header>
+   <container>1</container>
+  </customwidget>
+ </customwidgets>
+ <resources>
+  <include location="../../../sdrbase/resources/res.qrc"/>
+ </resources>
+ <connections/>
+</ui>

plugins/channel/bfm/bfmplugin.cpp

@@ -0,0 +1,55 @@
+#include <QtPlugin>
+#include <QAction>
+#include "plugin/pluginapi.h"
+
+#include "bfmplugin.h"
+
+#include "bfmdemodgui.h"
+
+const PluginDescriptor BFMPlugin::m_pluginDescriptor = {
+	QString("Broadcast FM Demodulator"),
+	QString("---"),
+	QString("(c) Edouard Griffiths, F4EXB"),
+	QString("https://github.com/f4exb/sdrangel"),
+	true,
+	QString("https://github.com/f4exb/sdrangel")
+};
+
+BFMPlugin::BFMPlugin(QObject* parent) :
+	QObject(parent)
+{
+}
+
+const PluginDescriptor& BFMPlugin::getPluginDescriptor() const
+{
+	return m_pluginDescriptor;
+}
+
+void BFMPlugin::initPlugin(PluginAPI* pluginAPI)
+{
+	m_pluginAPI = pluginAPI;
+
+	// register BFM demodulator
+	QAction* action = new QAction(tr("&Broadcast FM Demodulator"), this);
+	connect(action, SIGNAL(triggered()), this, SLOT(createInstanceBFM()));
+	m_pluginAPI->registerChannel("sdrangel.channel.bfm", this, action);
+}
+
+PluginGUI* BFMPlugin::createChannel(const QString& channelName)
+{
+	if(channelName == "sdrangel.channel.bfm") {
+		BFMDemodGUI* gui = BFMDemodGUI::create(m_pluginAPI);
+		m_pluginAPI->registerChannelInstance("sdrangel.channel.bfm", gui);
+		m_pluginAPI->addChannelRollup(gui);
+		return gui;
+	} else {
+		return 0;
+	}
+}
+
+void BFMPlugin::createInstanceBFM()
+{
+	BFMDemodGUI* gui = BFMDemodGUI::create(m_pluginAPI);
+	m_pluginAPI->registerChannelInstance("sdrangel.channel.bfm", gui);
+	m_pluginAPI->addChannelRollup(gui);
+}

plugins/channel/bfm/bfmplugin.h

@@ -0,0 +1,29 @@
+#ifndef INCLUDE_BFMPLUGIN_H
+#define INCLUDE_BFMPLUGIN_H
+
+#include <QObject>
+#include "plugin/plugininterface.h"
+
+class BFMPlugin : public QObject, PluginInterface {
+	Q_OBJECT
+	Q_INTERFACES(PluginInterface)
+	Q_PLUGIN_METADATA(IID "sdrangel.channel.bfm")
+
+public:
+	explicit BFMPlugin(QObject* parent = 0);
+
+	const PluginDescriptor& getPluginDescriptor() const;
+	void initPlugin(PluginAPI* pluginAPI);
+
+	PluginGUI* createChannel(const QString& channelName);
+
+private:
+	static const PluginDescriptor m_pluginDescriptor;
+
+	PluginAPI* m_pluginAPI;
+
+private slots:
+	void createInstanceBFM();
+};
+
+#endif // INCLUDE_BFMPLUGIN_H