cannam@41: /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
cannam@41: 
cannam@41: /*
cannam@41:     Vamp
cannam@41: 
cannam@41:     An API for audio analysis and feature extraction plugins.
cannam@41: 
cannam@41:     Centre for Digital Music, Queen Mary, University of London.
cannam@41:     This file copyright 2006 Dan Stowell.
cannam@41:   
cannam@41:     Permission is hereby granted, free of charge, to any person
cannam@41:     obtaining a copy of this software and associated documentation
cannam@41:     files (the "Software"), to deal in the Software without
cannam@41:     restriction, including without limitation the rights to use, copy,
cannam@41:     modify, merge, publish, distribute, sublicense, and/or sell copies
cannam@41:     of the Software, and to permit persons to whom the Software is
cannam@41:     furnished to do so, subject to the following conditions:
cannam@41: 
cannam@41:     The above copyright notice and this permission notice shall be
cannam@41:     included in all copies or substantial portions of the Software.
cannam@41: 
cannam@41:     THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
cannam@41:     EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
cannam@41:     MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
cannam@41:     NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR
cannam@41:     ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
cannam@41:     CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
cannam@41:     WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
cannam@41: 
cannam@41:     Except as contained in this notice, the names of the Centre for
cannam@41:     Digital Music; Queen Mary, University of London; and Chris Cannam
cannam@41:     shall not be used in advertising or otherwise to promote the sale,
cannam@41:     use or other dealings in this Software without prior written
cannam@41:     authorization.
cannam@41: */
cannam@41: 
cannam@41: #include "AmplitudeFollower.h"
cannam@41: 
cannam@41: #include <cmath>
cannam@41: 
cannam@41: #include <string>
cannam@41: #include <vector>
cannam@41: #include <iostream>
cannam@41: 
cannam@41: using std::string;
cannam@41: using std::vector;
cannam@41: using std::cerr;
cannam@41: using std::endl;
cannam@41: 
cannam@41: /*
cannam@41:  * An implementation of SuperCollider's amplitude-follower algorithm
cannam@41:  * as a simple Vamp plugin.
cannam@41:  */
cannam@41: 
cannam@41: AmplitudeFollower::AmplitudeFollower(float inputSampleRate) :
cannam@41:     Plugin(inputSampleRate),
cannam@41:     m_stepSize(0),
cannam@41:     m_previn(0.0f),
cannam@41:     m_clampcoef(0.01f),
cannam@41:     m_relaxcoef(0.01f)
cannam@41: {
cannam@41: }
cannam@41: 
cannam@41: AmplitudeFollower::~AmplitudeFollower()
cannam@41: {
cannam@41: }
cannam@41: 
cannam@41: string
cannam@41: AmplitudeFollower::getName() const
cannam@41: {
cannam@41:     return "amplitudefollower";
cannam@41: }
cannam@41: 
cannam@41: string
cannam@41: AmplitudeFollower::getDescription() const
cannam@41: {
cannam@41:     return "Amplitude Follower";
cannam@41: }
cannam@41: 
cannam@41: string
cannam@41: AmplitudeFollower::getMaker() const
cannam@41: {
cannam@41:     return "Queen Mary, University of London";
cannam@41: }
cannam@41: 
cannam@41: int
cannam@41: AmplitudeFollower::getPluginVersion() const
cannam@41: {
cannam@41:     return 1;
cannam@41: }
cannam@41: 
cannam@41: string
cannam@41: AmplitudeFollower::getCopyright() const
cannam@41: {
cannam@41:     return "Code copyright 2006 Dan Stowell; method from SuperCollider.  Freely redistributable (BSD license)";
cannam@41: }
cannam@41: 
cannam@41: bool
cannam@41: AmplitudeFollower::initialise(size_t channels, size_t stepSize, size_t blockSize)
cannam@41: {
cannam@41:     if (channels < getMinChannelCount() ||
cannam@41: 	channels > getMaxChannelCount()) return false;
cannam@41: 
cannam@41:     m_stepSize = std::min(stepSize, blockSize);
cannam@41: 	
cannam@41:     // Translate the coefficients 
cannam@41:     // from their "convenient" 60dB convergence-time values
cannam@41:     // to real coefficients
cannam@41:     m_clampcoef = m_clampcoef==0.0 ? 0.0 : exp(log(0.1)/(m_clampcoef * m_inputSampleRate));
cannam@41:     m_relaxcoef = m_relaxcoef==0.0 ? 0.0 : exp(log(0.1)/(m_relaxcoef * m_inputSampleRate));
cannam@41: 
cannam@41:     return true;
cannam@41: }
cannam@41: 
cannam@41: void
cannam@41: AmplitudeFollower::reset()
cannam@41: {
cannam@41:     m_previn = 0.0f;
cannam@41: }
cannam@41: 
cannam@41: AmplitudeFollower::OutputList
cannam@41: AmplitudeFollower::getOutputDescriptors() const
cannam@41: {
cannam@41:     OutputList list;
cannam@41: 
cannam@41:     OutputDescriptor sca;
cannam@41:     sca.name = "amplitude";
cannam@41:     sca.unit = "V";
cannam@41:     sca.description = "Amplitude";
cannam@41:     sca.hasFixedBinCount = true;
cannam@41:     sca.binCount = 1;
cannam@41:     sca.hasKnownExtents = false;
cannam@41:     sca.isQuantized = false;
cannam@41:     sca.sampleType = OutputDescriptor::OneSamplePerStep;
cannam@41:     list.push_back(sca);
cannam@41: 
cannam@41:     return list;
cannam@41: }
cannam@41: 
cannam@41: AmplitudeFollower::ParameterList
cannam@41: AmplitudeFollower::getParameterDescriptors() const
cannam@41: {
cannam@41:     ParameterList list;
cannam@41: 	
cannam@41:     ParameterDescriptor att;
cannam@41:     att.name = "attack";
cannam@41:     att.description = "Attack time";
cannam@41:     att.unit = "s";
cannam@41:     att.minValue = 0.0f;
cannam@41:     att.maxValue = 1.f;
cannam@41:     att.defaultValue = 0.01f;
cannam@41:     att.isQuantized = false;
cannam@41:     
cannam@41:     list.push_back(att);
cannam@41:     
cannam@41:     ParameterDescriptor dec;
cannam@41:     dec.name = "release";
cannam@41:     dec.description = "Release time";
cannam@41:     dec.unit = "s";
cannam@41:     dec.minValue = 0.0f;
cannam@41:     dec.maxValue = 1.f;
cannam@41:     dec.defaultValue = 0.01f;
cannam@41:     dec.isQuantized = false;
cannam@41:     
cannam@41:     list.push_back(dec);
cannam@41:     
cannam@41:     return list;
cannam@41: }
cannam@41: 
cannam@41: void AmplitudeFollower::setParameter(std::string paramname, float newval)
cannam@41: {
cannam@41:     if (paramname == "attack") {
cannam@41:         m_clampcoef = newval;
cannam@41:     } else if (paramname == "release") {
cannam@41:         m_relaxcoef = newval;
cannam@41:     }
cannam@41: }
cannam@41: 
cannam@41: float AmplitudeFollower::getParameter(std::string paramname) const
cannam@41: {
cannam@41:     if (paramname == "attack") {
cannam@41:         return m_clampcoef;
cannam@41:     } else if (paramname == "release") {
cannam@41:         return m_relaxcoef;
cannam@41:     }
cannam@41: 
cannam@41:     return 0.0f;
cannam@41: }
cannam@41: 
cannam@41: AmplitudeFollower::FeatureSet
cannam@41: AmplitudeFollower::process(float **inputBuffers, Vamp::RealTime timestamp)
cannam@41: {
cannam@41:     if (m_stepSize == 0) {
cannam@41: 	cerr << "ERROR: AmplitudeFollower::process: "
cannam@41: 	     << "AmplitudeFollower has not been initialised"
cannam@41: 	     << endl;
cannam@41: 	return FeatureSet();
cannam@41:     }
cannam@41: 
cannam@41:     float previn = m_previn;
cannam@41: 
cannam@41:     FeatureSet returnFeatures;
cannam@41: 	
cannam@41:     float val;
cannam@41:     float peak = 0.0f;
cannam@41: 
cannam@41:     for (size_t i = 0; i < m_stepSize; ++i) {
cannam@41: 
cannam@41:         val = fabs(inputBuffers[0][i]);
cannam@41: 		
cannam@41:         if (val < previn) {
cannam@41:             val = val + (previn - val) * m_relaxcoef;
cannam@41:         } else {
cannam@41:             val = val + (previn - val) * m_clampcoef;
cannam@41:         }
cannam@41: 
cannam@41:         if (val > peak) peak = val;
cannam@41:         previn = val;
cannam@41:     }
cannam@41: 
cannam@41:     m_previn = previn;
cannam@41: 
cannam@41:     // Now store the "feature" (peak amp) for this sample
cannam@41:     Feature feature;
cannam@41:     feature.hasTimestamp = false;
cannam@41:     feature.values.push_back(peak);
cannam@41:     returnFeatures[0].push_back(feature);
cannam@41: 
cannam@41:     return returnFeatures;
cannam@41: }
cannam@41: 
cannam@41: AmplitudeFollower::FeatureSet
cannam@41: AmplitudeFollower::getRemainingFeatures()
cannam@41: {
cannam@41:     return FeatureSet();
cannam@41: }
cannam@41: