WSJT-X/Modulator/Modulator.cpp
2020-08-03 01:39:25 +01:00

377 lines
12 KiB
C++

#include "Modulator.hpp"
#include <limits>
#include <qmath.h>
#include <QDateTime>
#if QT_VERSION >= QT_VERSION_CHECK(5, 15, 0)
#include <QRandomGenerator>
#endif
#include <QDebug>
#include "widgets/mainwindow.h" // TODO: G4WJS - break this dependency
#include "Audio/soundout.h"
#include "commons.h"
#include "moc_Modulator.cpp"
extern float gran(); // Noise generator (for tests only)
#define RAMP_INCREMENT 64 // MUST be an integral factor of 2^16
#if defined (WSJT_SOFT_KEYING)
# define SOFT_KEYING WSJT_SOFT_KEYING
#else
# define SOFT_KEYING 1
#endif
double constexpr Modulator::m_twoPi;
// float wpm=20.0;
// unsigned m_nspd=1.2*48000.0/wpm;
// m_nspd=3072; //18.75 WPM
Modulator::Modulator (unsigned frameRate, double periodLengthInSeconds,
QObject * parent)
: AudioDevice {parent}
, m_quickClose {false}
, m_phi {0.0}
, m_toneSpacing {0.0}
, m_fSpread {0.0}
, m_period {periodLengthInSeconds}
, m_frameRate {frameRate}
, m_state {Idle}
, m_tuning {false}
, m_cwLevel {false}
, m_j0 {-1}
, m_toneFrequency0 {1500.0}
{
}
void Modulator::start (QString mode, unsigned symbolsLength, double framesPerSymbol,
double frequency, double toneSpacing,
SoundOutput * stream, Channel channel,
bool synchronize, bool fastMode, double dBSNR, double TRperiod)
{
// qDebug () << "mode:" << mode << "symbolsLength:" << symbolsLength << "framesPerSymbol:" << framesPerSymbol << "frequency:" << frequency << "toneSpacing:" << toneSpacing << "channel:" << channel << "synchronize:" << synchronize << "fastMode:" << fastMode << "dBSNR:" << dBSNR << "TRperiod:" << TRperiod;
Q_ASSERT (stream);
// Time according to this computer which becomes our base time
qint64 ms0 = QDateTime::currentMSecsSinceEpoch() % 86400000;
unsigned mstr = ms0 % int(1000.0*m_period); // ms into the nominal Tx start time
if(m_state != Idle) stop();
m_quickClose = false;
m_symbolsLength = symbolsLength;
m_isym0 = std::numeric_limits<unsigned>::max (); // big number
m_frequency0 = 0.;
m_phi = 0.;
m_addNoise = dBSNR < 0.;
m_nsps = framesPerSymbol;
m_frequency = frequency;
m_amp = std::numeric_limits<qint16>::max ();
m_toneSpacing = toneSpacing;
m_bFastMode=fastMode;
m_TRperiod=TRperiod;
unsigned delay_ms=1000;
if(mode=="FT8" or (mode=="FST4" and m_nsps==720)) delay_ms=500; //FT8, FST4-15
if(mode=="FT4") delay_ms=300; //FT4
// noise generator parameters
if (m_addNoise) {
m_snr = qPow (10.0, 0.05 * (dBSNR - 6.0));
m_fac = 3000.0;
if (m_snr > 1.0) m_fac = 3000.0 / m_snr;
}
m_silentFrames = 0;
m_ic=0;
if (!m_tuning && !m_bFastMode)
{
// calculate number of silent frames to send, so that audio will
// start at the nominal time "delay_ms" into the Tx sequence.
if (synchronize)
{
if(delay_ms > mstr) m_silentFrames = (delay_ms - mstr) * m_frameRate / 1000;
}
// adjust for late starts
if(!m_silentFrames && mstr >= delay_ms)
{
m_ic = (mstr - delay_ms) * m_frameRate / 1000;
}
}
initialize (QIODevice::ReadOnly, channel);
Q_EMIT stateChanged ((m_state = (synchronize && m_silentFrames) ?
Synchronizing : Active));
// qDebug() << "delay_ms:" << delay_ms << "mstr:" << mstr << "m_silentFrames:" << m_silentFrames << "m_ic:" << m_ic << "m_state:" << m_state;
m_stream = stream;
if (m_stream) m_stream->restart (this);
}
void Modulator::tune (bool newState)
{
m_tuning = newState;
if (!m_tuning) stop (true);
}
void Modulator::stop (bool quick)
{
m_quickClose = quick;
close ();
}
void Modulator::close ()
{
if (m_stream)
{
if (m_quickClose)
{
m_stream->reset ();
}
else
{
m_stream->stop ();
}
}
if (m_state != Idle)
{
Q_EMIT stateChanged ((m_state = Idle));
}
AudioDevice::close ();
}
qint64 Modulator::readData (char * data, qint64 maxSize)
{
// qDebug () << "readData: maxSize:" << maxSize;
double toneFrequency=1500.0;
if(m_nsps==6) {
toneFrequency=1000.0;
m_frequency=1000.0;
m_frequency0=1000.0;
}
if(maxSize==0) return 0;
Q_ASSERT (!(maxSize % qint64 (bytesPerFrame ()))); // no torn frames
Q_ASSERT (isOpen ());
qint64 numFrames (maxSize / bytesPerFrame ());
qint16 * samples (reinterpret_cast<qint16 *> (data));
qint16 * end (samples + numFrames * (bytesPerFrame () / sizeof (qint16)));
qint64 framesGenerated (0);
// if(m_ic==0) qDebug() << "aa" << 0.001*(QDateTime::currentMSecsSinceEpoch() % qint64(1000*m_TRperiod))
// << m_state << m_TRperiod << m_silentFrames << m_ic << foxcom_.wave[m_ic];
switch (m_state)
{
case Synchronizing:
{
if (m_silentFrames) { // send silence up to end of start delay
framesGenerated = qMin (m_silentFrames, numFrames);
do
{
samples = load (0, samples); // silence
} while (--m_silentFrames && samples != end);
if (!m_silentFrames)
{
Q_EMIT stateChanged ((m_state = Active));
}
}
m_cwLevel = false;
m_ramp = 0; // prepare for CW wave shaping
}
// fall through
case Active:
{
unsigned int isym=0;
if(!m_tuning) isym=m_ic/(4.0*m_nsps); // Actual fsample=48000
bool slowCwId=((isym >= m_symbolsLength) && (icw[0] > 0)) && (!m_bFastMode);
if(m_TRperiod==3.0) slowCwId=false;
bool fastCwId=false;
static bool bCwId=false;
qint64 ms = QDateTime::currentMSecsSinceEpoch();
float tsec=0.001*(ms % int(1000*m_TRperiod));
if(m_bFastMode and (icw[0]>0) and (tsec > (m_TRperiod-5.0))) fastCwId=true;
if(!m_bFastMode) m_nspd=2560; // 22.5 WPM
// qDebug() << "Mod A" << m_ic << isym << tsec;
if(slowCwId or fastCwId) { // Transmit CW ID?
m_dphi = m_twoPi*m_frequency/m_frameRate;
if(m_bFastMode and !bCwId) {
m_frequency=1500; // Set params for CW ID
m_dphi = m_twoPi*m_frequency/m_frameRate;
m_symbolsLength=126;
m_nsps=4096.0*12000.0/11025.0;
m_ic=2246949;
m_nspd=2560; // 22.5 WPM
if(icw[0]*m_nspd/48000.0 > 4.0) m_nspd=4.0*48000.0/icw[0]; //Faster CW for long calls
}
bCwId=true;
unsigned ic0 = m_symbolsLength * 4 * m_nsps;
unsigned j(0);
while (samples != end) {
j = (m_ic - ic0)/m_nspd + 1; // symbol of this sample
bool level {bool (icw[j])};
m_phi += m_dphi;
if (m_phi > m_twoPi) m_phi -= m_twoPi;
qint16 sample=0;
float amp=32767.0;
float x=0;
if(m_ramp!=0) {
x=qSin(float(m_phi));
if(SOFT_KEYING) {
amp=qAbs(qint32(m_ramp));
if(amp>32767.0) amp=32767.0;
}
sample=round(amp*x);
}
if(m_bFastMode) {
sample=0;
if(level) sample=32767.0*x;
}
if (int (j) <= icw[0] && j < NUM_CW_SYMBOLS) { // stop condition
samples = load (postProcessSample (sample), samples);
++framesGenerated;
++m_ic;
} else {
Q_EMIT stateChanged ((m_state = Idle));
return framesGenerated * bytesPerFrame ();
}
// adjust ramp
if ((m_ramp != 0 && m_ramp != std::numeric_limits<qint16>::min ()) || level != m_cwLevel) {
// either ramp has terminated at max/min or direction has changed
m_ramp += RAMP_INCREMENT; // ramp
}
m_cwLevel = level;
}
return framesGenerated * bytesPerFrame ();
} else {
bCwId=false;
} //End of code for CW ID
double const baud (12000.0 / m_nsps);
// fade out parameters (no fade out for tuning)
unsigned int i0,i1;
if(m_tuning) {
i1 = i0 = (m_bFastMode ? 999999 : 9999) * m_nsps;
} else {
i0=(m_symbolsLength - 0.017) * 4.0 * m_nsps;
i1= m_symbolsLength * 4.0 * m_nsps;
}
if(m_bFastMode and !m_tuning) {
i1=m_TRperiod*48000.0 - 24000.0;
i0=i1-816;
}
qint16 sample;
while (samples != end && m_ic <= i1) {
isym=0;
if(!m_tuning and m_TRperiod!=3.0) isym=m_ic/(4.0*m_nsps); //Actual fsample=48000
if(m_bFastMode) isym=isym%m_symbolsLength;
if (isym != m_isym0 || m_frequency != m_frequency0) {
if(itone[0]>=100) {
m_toneFrequency0=itone[0];
} else {
if(m_toneSpacing==0.0) {
m_toneFrequency0=m_frequency + itone[isym]*baud;
} else {
m_toneFrequency0=m_frequency + itone[isym]*m_toneSpacing;
}
}
m_dphi = m_twoPi * m_toneFrequency0 / m_frameRate;
m_isym0 = isym;
m_frequency0 = m_frequency; //???
}
int j=m_ic/480;
if(m_fSpread>0.0 and j!=m_j0) {
#if QT_VERSION >= QT_VERSION_CHECK(5, 15, 0)
float x1=QRandomGenerator::global ()->generateDouble ();
float x2=QRandomGenerator::global ()->generateDouble ();
#else
float x1=(float)qrand()/RAND_MAX;
float x2=(float)qrand()/RAND_MAX;
#endif
toneFrequency = m_toneFrequency0 + 0.5*m_fSpread*(x1+x2-1.0);
m_dphi = m_twoPi * toneFrequency / m_frameRate;
m_j0=j;
}
m_phi += m_dphi;
if (m_phi > m_twoPi) m_phi -= m_twoPi;
if (m_ic > i0) m_amp = 0.98 * m_amp;
if (m_ic > i1) m_amp = 0.0;
sample=qRound(m_amp*qSin(m_phi));
//Here's where we transmit from a precomputed wave[] array:
if(!m_tuning and (m_toneSpacing < 0)) {
m_amp=32767.0;
sample=qRound(m_amp*foxcom_.wave[m_ic]);
}
/*
if((m_ic<1000 or (4*m_symbolsLength*m_nsps - m_ic) < 1000) and (m_ic%10)==0) {
qDebug() << "cc" << QDateTime::currentDateTimeUtc().toString("hh:mm:ss.zzz") << m_ic << sample;
}
*/
samples = load(postProcessSample(sample), samples);
++framesGenerated;
++m_ic;
}
// qDebug() << "dd" << QDateTime::currentDateTimeUtc().toString("hh:mm:ss.zzz")
// << m_ic << i1 << foxcom_.wave[m_ic] << framesGenerated;
if (m_amp == 0.0) { // TODO G4WJS: compare double with zero might not be wise
if (icw[0] == 0) {
// no CW ID to send
Q_EMIT stateChanged ((m_state = Idle));
return framesGenerated * bytesPerFrame ();
}
m_phi = 0.0;
}
m_frequency0 = m_frequency;
// done for this chunk - continue on next call
// qDebug() << "Mod B" << m_ic << i1 << 0.001*(QDateTime::currentMSecsSinceEpoch() % (1000*m_TRperiod));
while (samples != end) // pad block with silence
{
samples = load (0, samples);
++framesGenerated;
}
return framesGenerated * bytesPerFrame ();
}
// fall through
case Idle:
break;
}
Q_ASSERT (Idle == m_state);
return 0;
}
qint16 Modulator::postProcessSample (qint16 sample) const
{
if (m_addNoise) { // Test frame, we'll add noise
qint32 s = m_fac * (gran () + sample * m_snr / 32768.0);
if (s > std::numeric_limits<qint16>::max ()) {
s = std::numeric_limits<qint16>::max ();
}
if (s < std::numeric_limits<qint16>::min ()) {
s = std::numeric_limits<qint16>::min ();
}
sample = s;
}
return sample;
}