cannam@97: /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
cannam@97: 
cannam@97: /*
cannam@97:     Vamp
cannam@97: 
cannam@97:     An API for audio analysis and feature extraction plugins.
cannam@97: 
cannam@97:     Centre for Digital Music, Queen Mary, University of London.
cannam@97:     This file copyright 2006 Dan Stowell.
cannam@97:   
cannam@97:     Permission is hereby granted, free of charge, to any person
cannam@97:     obtaining a copy of this software and associated documentation
cannam@97:     files (the "Software"), to deal in the Software without
cannam@97:     restriction, including without limitation the rights to use, copy,
cannam@97:     modify, merge, publish, distribute, sublicense, and/or sell copies
cannam@97:     of the Software, and to permit persons to whom the Software is
cannam@97:     furnished to do so, subject to the following conditions:
cannam@97: 
cannam@97:     The above copyright notice and this permission notice shall be
cannam@97:     included in all copies or substantial portions of the Software.
cannam@97: 
cannam@97:     THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
cannam@97:     EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
cannam@97:     MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
cannam@97:     NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR
cannam@97:     ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
cannam@97:     CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
cannam@97:     WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
cannam@97: 
cannam@97:     Except as contained in this notice, the names of the Centre for
cannam@97:     Digital Music; Queen Mary, University of London; and Chris Cannam
cannam@97:     shall not be used in advertising or otherwise to promote the sale,
cannam@97:     use or other dealings in this Software without prior written
cannam@97:     authorization.
cannam@97: */
cannam@97: 
cannam@97: #include "AmplitudeFollower.h"
cannam@97: 
cannam@97: #include <cmath>
cannam@97: 
cannam@97: #include <string>
cannam@97: #include <vector>
cannam@97: #include <iostream>
cannam@97: 
cannam@97: using std::string;
cannam@97: using std::vector;
cannam@97: using std::cerr;
cannam@97: using std::endl;
cannam@97: 
cannam@97: /**
cannam@97:  * An implementation of SuperCollider's amplitude-follower algorithm
cannam@97:  * as a simple Vamp plugin.
cannam@97:  */
cannam@97: 
cannam@97: AmplitudeFollower::AmplitudeFollower(float inputSampleRate) :
cannam@97:     Plugin(inputSampleRate),
cannam@97:     m_stepSize(0),
cannam@97:     m_previn(0.0f),
cannam@97:     m_clampcoef(0.01f),
cannam@97:     m_relaxcoef(0.01f)
cannam@97: {
cannam@97: }
cannam@97: 
cannam@97: AmplitudeFollower::~AmplitudeFollower()
cannam@97: {
cannam@97: }
cannam@97: 
cannam@97: string
cannam@97: AmplitudeFollower::getIdentifier() const
cannam@97: {
cannam@97:     return "amplitudefollower";
cannam@97: }
cannam@97: 
cannam@97: string
cannam@97: AmplitudeFollower::getName() const
cannam@97: {
cannam@97:     return "Amplitude Follower";
cannam@97: }
cannam@97: 
cannam@97: string
cannam@97: AmplitudeFollower::getDescription() const
cannam@97: {
cannam@97:     return "Track the amplitude of the audio signal";
cannam@97: }
cannam@97: 
cannam@97: string
cannam@97: AmplitudeFollower::getMaker() const
cannam@97: {
cannam@97:     return "Vamp SDK Example Plugins";
cannam@97: }
cannam@97: 
cannam@97: int
cannam@97: AmplitudeFollower::getPluginVersion() const
cannam@97: {
cannam@97:     return 1;
cannam@97: }
cannam@97: 
cannam@97: string
cannam@97: AmplitudeFollower::getCopyright() const
cannam@97: {
cannam@97:     return "Code copyright 2006 Dan Stowell; method from SuperCollider.  Freely redistributable (BSD license)";
cannam@97: }
cannam@97: 
cannam@97: bool
cannam@97: AmplitudeFollower::initialise(size_t channels, size_t stepSize, size_t blockSize)
cannam@97: {
cannam@97:     if (channels < getMinChannelCount() ||
cannam@97: 	channels > getMaxChannelCount()) return false;
cannam@97: 
cannam@97:     m_stepSize = std::min(stepSize, blockSize);
cannam@97: 	
cannam@97:     // Translate the coefficients 
cannam@97:     // from their "convenient" 60dB convergence-time values
cannam@97:     // to real coefficients
cannam@97:     m_clampcoef = m_clampcoef==0.0 ? 0.0 : exp(log(0.1)/(m_clampcoef * m_inputSampleRate));
cannam@97:     m_relaxcoef = m_relaxcoef==0.0 ? 0.0 : exp(log(0.1)/(m_relaxcoef * m_inputSampleRate));
cannam@97: 
cannam@97:     return true;
cannam@97: }
cannam@97: 
cannam@97: void
cannam@97: AmplitudeFollower::reset()
cannam@97: {
cannam@97:     m_previn = 0.0f;
cannam@97: }
cannam@97: 
cannam@97: AmplitudeFollower::OutputList
cannam@97: AmplitudeFollower::getOutputDescriptors() const
cannam@97: {
cannam@97:     OutputList list;
cannam@97: 
cannam@97:     OutputDescriptor sca;
cannam@97:     sca.identifier = "amplitude";
cannam@97:     sca.name = "Amplitude";
cannam@97:     sca.description = "The peak tracked amplitude for the current processing block";
cannam@97:     sca.unit = "V";
cannam@97:     sca.hasFixedBinCount = true;
cannam@97:     sca.binCount = 1;
cannam@97:     sca.hasKnownExtents = false;
cannam@97:     sca.isQuantized = false;
cannam@97:     sca.sampleType = OutputDescriptor::OneSamplePerStep;
cannam@97:     list.push_back(sca);
cannam@97: 
cannam@97:     return list;
cannam@97: }
cannam@97: 
cannam@97: AmplitudeFollower::ParameterList
cannam@97: AmplitudeFollower::getParameterDescriptors() const
cannam@97: {
cannam@97:     ParameterList list;
cannam@97: 	
cannam@97:     ParameterDescriptor att;
cannam@97:     att.identifier = "attack";
cannam@97:     att.name = "Attack time";
cannam@97:     att.description = "The 60dB convergence time for an increase in amplitude";
cannam@97:     att.unit = "s";
cannam@97:     att.minValue = 0.0f;
cannam@97:     att.maxValue = 1.f;
cannam@97:     att.defaultValue = 0.01f;
cannam@97:     att.isQuantized = false;
cannam@97:     
cannam@97:     list.push_back(att);
cannam@97:     
cannam@97:     ParameterDescriptor dec;
cannam@97:     dec.identifier = "release";
cannam@97:     dec.name = "Release time";
cannam@97:     dec.description = "The 60dB convergence time for a decrease in amplitude";
cannam@97:     dec.unit = "s";
cannam@97:     dec.minValue = 0.0f;
cannam@97:     dec.maxValue = 1.f;
cannam@97:     dec.defaultValue = 0.01f;
cannam@97:     dec.isQuantized = false;
cannam@97:     
cannam@97:     list.push_back(dec);
cannam@97:     
cannam@97:     return list;
cannam@97: }
cannam@97: 
cannam@97: void AmplitudeFollower::setParameter(std::string paramid, float newval)
cannam@97: {
cannam@97:     if (paramid == "attack") {
cannam@97:         m_clampcoef = newval;
cannam@97:     } else if (paramid == "release") {
cannam@97:         m_relaxcoef = newval;
cannam@97:     }
cannam@97: }
cannam@97: 
cannam@97: float AmplitudeFollower::getParameter(std::string paramid) const
cannam@97: {
cannam@97:     if (paramid == "attack") {
cannam@97:         return m_clampcoef;
cannam@97:     } else if (paramid == "release") {
cannam@97:         return m_relaxcoef;
cannam@97:     }
cannam@97: 
cannam@97:     return 0.0f;
cannam@97: }
cannam@97: 
cannam@97: AmplitudeFollower::FeatureSet
cannam@97: AmplitudeFollower::process(const float *const *inputBuffers,
cannam@97:                            Vamp::RealTime timestamp)
cannam@97: {
cannam@97:     if (m_stepSize == 0) {
cannam@97: 	cerr << "ERROR: AmplitudeFollower::process: "
cannam@97: 	     << "AmplitudeFollower has not been initialised"
cannam@97: 	     << endl;
cannam@97: 	return FeatureSet();
cannam@97:     }
cannam@97: 
cannam@97:     float previn = m_previn;
cannam@97: 
cannam@97:     FeatureSet returnFeatures;
cannam@97: 	
cannam@97:     float val;
cannam@97:     float peak = 0.0f;
cannam@97: 
cannam@97:     for (size_t i = 0; i < m_stepSize; ++i) {
cannam@97: 
cannam@97:         val = fabs(inputBuffers[0][i]);
cannam@97: 		
cannam@97:         if (val < previn) {
cannam@97:             val = val + (previn - val) * m_relaxcoef;
cannam@97:         } else {
cannam@97:             val = val + (previn - val) * m_clampcoef;
cannam@97:         }
cannam@97: 
cannam@97:         if (val > peak) peak = val;
cannam@97:         previn = val;
cannam@97:     }
cannam@97: 
cannam@97:     m_previn = previn;
cannam@97: 
cannam@97:     // Now store the "feature" (peak amp) for this sample
cannam@97:     Feature feature;
cannam@97:     feature.hasTimestamp = false;
cannam@97:     feature.values.push_back(peak);
cannam@97:     returnFeatures[0].push_back(feature);
cannam@97: 
cannam@97:     return returnFeatures;
cannam@97: }
cannam@97: 
cannam@97: AmplitudeFollower::FeatureSet
cannam@97: AmplitudeFollower::getRemainingFeatures()
cannam@97: {
cannam@97:     return FeatureSet();
cannam@97: }
cannam@97: