sdrangel/plugins/channelrx/demodam/amdemod.cpp

///////////////////////////////////////////////////////////////////////////////////
// Copyright (C) 2015 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                  //
//                                                                               //
// 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 "amdemod.h"

#include <QTime>
#include <QDebug>

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

#include "dsp/downchannelizer.h"
#include "audio/audiooutput.h"
#include "dsp/dspengine.h"
#include "dsp/pidcontroller.h"

MESSAGE_CLASS_DEFINITION(AMDemod::MsgConfigureAMDemod, Message)

const int AMDemod::m_udpBlockSize = 512;

AMDemod::AMDemod() :
    m_squelchOpen(false),
	m_magsqSum(0.0f),
	m_magsqPeak(0.0f),
	m_magsqCount(0),
	m_movingAverage(40, 0),
    m_volumeAGC(1200, 1.0),
    m_audioFifo(48000),
    m_settingsMutex(QMutex::Recursive)
{
	setObjectName("AMDemod");

	m_config.m_inputSampleRate = 96000;
	m_config.m_inputFrequencyOffset = 0;
	m_config.m_rfBandwidth = 5000;
	m_config.m_squelch = -40.0;
	m_config.m_volume = 2.0;
	m_config.m_audioSampleRate = DSPEngine::instance()->getAudioSampleRate();

	apply();

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

	m_movingAverage.resize(16, 0);
	m_volumeAGC.resize(4096, 0.003, 0);
	m_magsq = 0.0;

	DSPEngine::instance()->addAudioSink(&m_audioFifo);
    m_udpBufferAudio = new UDPSink<qint16>(this, m_udpBlockSize, m_config.m_udpPort);
}

AMDemod::~AMDemod()
{
	DSPEngine::instance()->removeAudioSink(&m_audioFifo);
    delete m_udpBufferAudio;
}

void AMDemod::configure(MessageQueue* messageQueue,
        Real rfBandwidth,
        Real volume,
        Real squelch,
        bool audioMute,
        bool bandpassEnable,
        bool copyAudioToUDP,
        const QString& udpAddress,
        quint16 udpPort,
        bool force)
{
	Message* cmd = MsgConfigureAMDemod::create(rfBandwidth,
	        volume,
	        squelch,
	        audioMute,
	        bandpassEnable,
            copyAudioToUDP,
            udpAddress,
            udpPort,
            force);
	messageQueue->push(cmd);
}

void AMDemod::feed(const SampleVector::const_iterator& begin, const SampleVector::const_iterator& end, bool firstOfBurst __attribute__((unused)))
{
	Complex ci;

	m_settingsMutex.lock();

	for (SampleVector::const_iterator it = begin; it != end; ++it)
	{
		//Complex c(it->real() / 32768.0, it->imag() / 32768.0);
		Complex c(it->real(), it->imag());
		c *= m_nco.nextIQ();

		if (m_interpolatorDistance < 1.0f) // interpolate
		{
            processOneSample(ci);

		    while (m_interpolator.interpolate(&m_interpolatorDistanceRemain, c, &ci))
            {
                processOneSample(ci);
            }

            m_interpolatorDistanceRemain += m_interpolatorDistance;
		}
		else // decimate
		{
	        if (m_interpolator.decimate(&m_interpolatorDistanceRemain, c, &ci))
	        {
	            processOneSample(ci);
	            m_interpolatorDistanceRemain += m_interpolatorDistance;
	        }
		}
	}

	if (m_audioBufferFill > 0)
	{
		uint res = m_audioFifo.write((const quint8*)&m_audioBuffer[0], m_audioBufferFill, 10);

		if (res != m_audioBufferFill)
		{
			qDebug("AMDemod::feed: %u/%u tail samples written", res, m_audioBufferFill);
		}

		m_audioBufferFill = 0;
	}

	m_settingsMutex.unlock();
}

void AMDemod::start()
{
	qDebug() << "AMDemod::start: m_inputSampleRate: " << m_config.m_inputSampleRate
			<< " m_inputFrequencyOffset: " << m_config.m_inputFrequencyOffset;

	m_squelchCount = 0;
	m_audioFifo.clear();
}

void AMDemod::stop()
{
}

bool AMDemod::handleMessage(const Message& cmd)
{
	qDebug() << "AMDemod::handleMessage";

	if (DownChannelizer::MsgChannelizerNotification::match(cmd))
	{
		DownChannelizer::MsgChannelizerNotification& notif = (DownChannelizer::MsgChannelizerNotification&) cmd;

		m_config.m_inputSampleRate = notif.getSampleRate();
		m_config.m_inputFrequencyOffset = notif.getFrequencyOffset();

		apply();

		qDebug() << "AMDemod::handleMessage: MsgChannelizerNotification:"
				<< " m_inputSampleRate: " << m_config.m_inputSampleRate
				<< " m_inputFrequencyOffset: " << m_config.m_inputFrequencyOffset;

		return true;
	}
	else if (MsgConfigureAMDemod::match(cmd))
	{
		MsgConfigureAMDemod& cfg = (MsgConfigureAMDemod&) cmd;

		m_config.m_rfBandwidth = cfg.getRFBandwidth();
		m_config.m_volume = cfg.getVolume();
		m_config.m_squelch = cfg.getSquelch();
		m_config.m_audioMute = cfg.getAudioMute();
		m_config.m_bandpassEnable = cfg.getBandpassEnable();
		m_config.m_copyAudioToUDP = cfg.getCopyAudioToUDP();
		m_config.m_udpAddress = cfg.getUDPAddress();
		m_config.m_udpPort = cfg.getUDPPort();

		apply(cfg.getForce());

		qDebug() << "AMDemod::handleMessage: MsgConfigureAMDemod:"
				<< " m_rfBandwidth: " << m_config.m_rfBandwidth
				<< " m_volume: " << m_config.m_volume
				<< " m_squelch: " << m_config.m_squelch
				<< " m_audioMute: " << m_config.m_audioMute
				<< " m_bandpassEnable: " << m_config.m_bandpassEnable
                << " m_copyAudioToUDP: " << m_config.m_copyAudioToUDP
                << " m_udpAddress: " << m_config.m_udpAddress
                << " m_udpPort: " << m_config.m_udpPort;

		return true;
	}
	else
	{
		return false;
	}
}

void AMDemod::apply(bool force)
{

	if ((m_config.m_inputFrequencyOffset != m_running.m_inputFrequencyOffset) ||
		(m_config.m_inputSampleRate != m_running.m_inputSampleRate) || force)
	{
		m_nco.setFreq(-m_config.m_inputFrequencyOffset, m_config.m_inputSampleRate);
	}

	if((m_config.m_inputSampleRate != m_running.m_inputSampleRate) ||
		(m_config.m_rfBandwidth != m_running.m_rfBandwidth) ||
		(m_config.m_audioSampleRate != m_running.m_audioSampleRate) ||
		(m_config.m_bandpassEnable != m_running.m_bandpassEnable) || force)
	{
		m_settingsMutex.lock();
		m_interpolator.create(16, m_config.m_inputSampleRate, m_config.m_rfBandwidth / 2.2f);
		m_interpolatorDistanceRemain = 0;
		m_interpolatorDistance = (Real) m_config.m_inputSampleRate / (Real) m_config.m_audioSampleRate;
		m_bandpass.create(301, m_config.m_audioSampleRate, 300.0, m_config.m_rfBandwidth / 2.0f);
		m_settingsMutex.unlock();
	}

	if ((m_config.m_squelch != m_running.m_squelch) || force)
	{
		m_squelchLevel = pow(10.0, m_config.m_squelch / 20.0);
		m_squelchLevel *= m_squelchLevel;
	}

    if ((m_config.m_udpAddress != m_running.m_udpAddress)
        || (m_config.m_udpPort != m_running.m_udpPort) || force)
    {
        m_udpBufferAudio->setAddress(m_config.m_udpAddress);
        m_udpBufferAudio->setPort(m_config.m_udpPort);
    }

	m_running = m_config;
}