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livetrax/libs/vamp-plugins/AmplitudeFollower.cpp
David Robillard 9f63ab9931 Merge with trunk R2978.
git-svn-id: svn://localhost/ardour2/branches/3.0@2988 d708f5d6-7413-0410-9779-e7cbd77b26cf
2008-02-02 03:57:35 +00:00

248 lines
5.9 KiB
C++

/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*- vi:set ts=8 sts=4 sw=4: */
/*
Vamp
An API for audio analysis and feature extraction plugins.
Centre for Digital Music, Queen Mary, University of London.
This file copyright 2006 Dan Stowell.
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 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.
Except as contained in this notice, the names of the Centre for
Digital Music; Queen Mary, University of London; and Chris Cannam
shall not be used in advertising or otherwise to promote the sale,
use or other dealings in this Software without prior written
authorization.
*/
#include "AmplitudeFollower.h"
#include <cmath>
#include <string>
#include <vector>
#include <iostream>
using std::string;
using std::vector;
using std::cerr;
using std::endl;
/**
* An implementation of SuperCollider's amplitude-follower algorithm
* as a simple Vamp plugin.
*/
AmplitudeFollower::AmplitudeFollower(float inputSampleRate) :
Plugin(inputSampleRate),
m_stepSize(0),
m_previn(0.0f),
m_clampcoef(0.01f),
m_relaxcoef(0.01f)
{
}
AmplitudeFollower::~AmplitudeFollower()
{
}
string
AmplitudeFollower::getIdentifier() const
{
return "amplitudefollower";
}
string
AmplitudeFollower::getName() const
{
return "Amplitude Follower";
}
string
AmplitudeFollower::getDescription() const
{
return "Track the amplitude of the audio signal";
}
string
AmplitudeFollower::getMaker() const
{
return "Vamp SDK Example Plugins";
}
int
AmplitudeFollower::getPluginVersion() const
{
return 1;
}
string
AmplitudeFollower::getCopyright() const
{
return "Code copyright 2006 Dan Stowell; method from SuperCollider. Freely redistributable (BSD license)";
}
bool
AmplitudeFollower::initialise(size_t channels, size_t stepSize, size_t blockSize)
{
if (channels < getMinChannelCount() ||
channels > getMaxChannelCount()) return false;
m_stepSize = std::min(stepSize, blockSize);
// Translate the coefficients
// from their "convenient" 60dB convergence-time values
// to real coefficients
m_clampcoef = m_clampcoef==0.0 ? 0.0 : exp(log(0.1)/(m_clampcoef * m_inputSampleRate));
m_relaxcoef = m_relaxcoef==0.0 ? 0.0 : exp(log(0.1)/(m_relaxcoef * m_inputSampleRate));
return true;
}
void
AmplitudeFollower::reset()
{
m_previn = 0.0f;
}
AmplitudeFollower::OutputList
AmplitudeFollower::getOutputDescriptors() const
{
OutputList list;
OutputDescriptor sca;
sca.identifier = "amplitude";
sca.name = "Amplitude";
sca.description = "";
sca.unit = "V";
sca.hasFixedBinCount = true;
sca.binCount = 1;
sca.hasKnownExtents = false;
sca.isQuantized = false;
sca.sampleType = OutputDescriptor::OneSamplePerStep;
list.push_back(sca);
return list;
}
AmplitudeFollower::ParameterList
AmplitudeFollower::getParameterDescriptors() const
{
ParameterList list;
ParameterDescriptor att;
att.identifier = "attack";
att.name = "Attack time";
att.description = "";
att.unit = "s";
att.minValue = 0.0f;
att.maxValue = 1.f;
att.defaultValue = 0.01f;
att.isQuantized = false;
list.push_back(att);
ParameterDescriptor dec;
dec.identifier = "release";
dec.name = "Release time";
dec.description = "";
dec.unit = "s";
dec.minValue = 0.0f;
dec.maxValue = 1.f;
dec.defaultValue = 0.01f;
dec.isQuantized = false;
list.push_back(dec);
return list;
}
void AmplitudeFollower::setParameter(std::string paramid, float newval)
{
if (paramid == "attack") {
m_clampcoef = newval;
} else if (paramid == "release") {
m_relaxcoef = newval;
}
}
float AmplitudeFollower::getParameter(std::string paramid) const
{
if (paramid == "attack") {
return m_clampcoef;
} else if (paramid == "release") {
return m_relaxcoef;
}
return 0.0f;
}
AmplitudeFollower::FeatureSet
AmplitudeFollower::process(const float *const *inputBuffers,
Vamp::RealTime timestamp)
{
if (m_stepSize == 0) {
cerr << "ERROR: AmplitudeFollower::process: "
<< "AmplitudeFollower has not been initialised"
<< endl;
return FeatureSet();
}
float previn = m_previn;
FeatureSet returnFeatures;
float val;
float peak = 0.0f;
for (size_t i = 0; i < m_stepSize; ++i) {
val = fabs(inputBuffers[0][i]);
if (val < previn) {
val = val + (previn - val) * m_relaxcoef;
} else {
val = val + (previn - val) * m_clampcoef;
}
if (val > peak) peak = val;
previn = val;
}
m_previn = previn;
// Now store the "feature" (peak amp) for this sample
Feature feature;
feature.hasTimestamp = false;
feature.values.push_back(peak);
returnFeatures[0].push_back(feature);
return returnFeatures;
}
AmplitudeFollower::FeatureSet
AmplitudeFollower::getRemainingFeatures()
{
return FeatureSet();
}