//*****************************************************************
/*
JackTrip: A System for High-Quality Audio Network Performance
over the Internet
Copyright (c) 2020 Julius Smith, Juan-Pablo Caceres, Chris Chafe.
SoundWIRE group at CCRMA, Stanford University.
Permission is hereby granted, free of charge, to any person
obtaining a copy of this software and associated documentation
files (the "Software"), to deal in the Software without
restriction, including without limitation the rights to use,
copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following
conditions:
The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.
*/
//*****************************************************************
/**
* \file Limiter.h
* \author Julius Smith, based on LoopBack.h
* \date May-Nov 2020
* \license MIT
*/
/** \brief Applies limiter_lad_mono from the faustlibraries distribution, compressors.lib
*
*/
#ifndef __LIMITER_H__
#define __LIMITER_H__
//#define SINE_TEST
#ifdef SINE_TEST
#include "limitertest.h"
#endif
#include <cassert>
#include <iostream>
#include <vector>
#include "ProcessPlugin.h"
#include "limiterdsp.h"
/** \brief The Limiter class confines the output dynamic range to a
* "dynamic range lane" determined by the assumed number of clients.
*/
class Limiter : public ProcessPlugin
{
public:
/// \brief The class constructor sets the number of channels to limit
Limiter(int numchans, int numclients, bool verboseFlag = false) // xtor
: mNumChannels(numchans)
, mNumClients(numclients)
, warningAmp(0.0)
, warnCount(0)
, peakMagnitude(0.0)
, nextWarning(1)
{
setVerbose(verboseFlag);
for (int i = 0; i < mNumChannels; i++) {
limiterP.push_back(new limiterdsp);
limiterUIP.push_back(new APIUI); // #included in limiterdsp.h
limiterP[i]->buildUserInterface(limiterUIP[i]);
#ifdef SINE_TEST
limiterTestP.push_back(new limitertest);
limiterTestUIP.push_back(new APIUI); // #included in limitertest.h
limiterTestP[i]->buildUserInterface(limiterTestUIP[i]);
#endif
}
// std::cout << "Limiter: constructed for "
// << mNumChannels << " channels and "
// << mNumClients << " assumed clients\n";
}
/// \brief The class destructor
virtual ~Limiter()
{
for (int i = 0; i < mNumChannels; i++) {
delete limiterP[i];
delete limiterUIP[i];
}
limiterP.clear();
limiterUIP.clear();
}
void init(int samplingRate) override
{
ProcessPlugin::init(samplingRate);
if (samplingRate != fSamplingFreq) {
std::cerr << "Sampling rate not set by superclass!\n";
std::exit(1);
}
fs = float(fSamplingFreq);
for (int i = 0; i < mNumChannels; i++) {
limiterP[i]->init(
fs); // compression filter parameters depend on sampling rate
int ndx = limiterUIP[i]->getParamIndex("NumClientsAssumed");
limiterUIP[i]->setParamValue(ndx, mNumClients);
#ifdef SINE_TEST
limiterTestP[i]->init(fs); // oscillator parameters depend on sampling rate
ndx = limiterTestUIP[i]->getParamIndex("Amp");
limiterTestUIP[i]->setParamValue(ndx, 0.2);
ndx = limiterTestUIP[i]->getParamIndex("Freq");
float sineFreq =
110.0 * pow(1.5, double(i))
* (mNumClients > 1 ? 1.25 : 1.0); // Maj 7 chord for stereo in & out
limiterTestUIP[i]->setParamValue(ndx, sineFreq);
#endif
}
inited = true;
}
int getNumInputs() override { return (mNumChannels); }
int getNumOutputs() override { return (mNumChannels); }
void compute(int nframes, float** inputs, float** outputs) override;
const char* getName() const override { return "Limiter"; }
void setWarningAmplitude(double wa)
{ // setting to 0 turns off warnings
warningAmp = std::max(0.0, std::min(1.0, wa));
}
private:
void checkAmplitudes(int nframes, float* buf)
{
const int maxWarningInterval{10000}; // this could become an option
assert(warningAmp > 0.0);
assert(mNumClients > 0);
for (int i = 0; i < nframes; i++) {
double tmp_sample = double(buf[i]);
double limiterAmp =
fabs(tmp_sample)
/ sqrt(double(mNumClients)); // KEEP IN SYNC with gain in
// ../faust-src/limiterdsp.dsp
if (limiterAmp >= warningAmp) {
warnCount++;
peakMagnitude = std::max(peakMagnitude, limiterAmp);
if (warnCount == nextWarning) {
double peakMagnitudeDB = 20.0 * std::log10(peakMagnitude);
double warningAmpDB = 20.0 * std::log10(warningAmp);
if (warnCount == 1) {
if (warningAmp == 1.0) {
std::cerr << "*** Limiter.cpp: Audio HARD-CLIPPED!\n";
fprintf(stderr,
"\tReduce your audio input level(s) by %0.1f dB to "
"avoid this.\n",
peakMagnitudeDB);
} else {
fprintf(stderr,
"*** Limiter.cpp: Amplitude levels must stay below "
"%0.1f dBFS to avoid compression.\n",
warningAmpDB);
fprintf(
stderr,
"\tReduce input level(s) by %0.1f dB to achieve this.\n",
peakMagnitudeDB - warningAmpDB);
}
} else {
fprintf(stderr,
"\tReduce audio input level(s) by %0.1f dB to avoid "
"limiter compression distortion.\n",
peakMagnitudeDB - warningAmpDB);
}
peakMagnitude = 0.0; // reset for next group measurement
if (nextWarning < maxWarningInterval) { // don't let it stop
// reporting for too long
nextWarning *= 10;
} else {
warnCount = 0;
}
} // warnCount==nextWarning
} // above warningAmp
} // loop over frames
} // checkAmplitudes()
private:
float fs;
int mNumChannels;
int mNumClients;
std::vector<limiterdsp*> limiterP;
std::vector<APIUI*> limiterUIP;
#ifdef SINE_TEST
std::vector<limitertest*> limiterTestP;
std::vector<APIUI*> limiterTestUIP;
#endif
double warningAmp;
uint32_t warnCount;
double peakMagnitude;
uint32_t nextWarning;
};
#endif