PowerSpectrum.cpp
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/* -*- 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.
Copyright 2008 QMUL.
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
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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,
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*/
#include "PowerSpectrum.h"
using std::string;
using std::cerr;
using std::endl;
#include <math.h>
PowerSpectrum::PowerSpectrum(float inputSampleRate) :
Plugin(inputSampleRate),
m_blockSize(0)
{
}
PowerSpectrum::~PowerSpectrum()
{
}
string
PowerSpectrum::getIdentifier() const
{
return "powerspectrum";
}
string
PowerSpectrum::getName() const
{
return "Simple Power Spectrum";
}
string
PowerSpectrum::getDescription() const
{
return "Return the power spectrum of a signal";
}
string
PowerSpectrum::getMaker() const
{
return "Vamp SDK Example Plugins";
}
int
PowerSpectrum::getPluginVersion() const
{
return 1;
}
string
PowerSpectrum::getCopyright() const
{
return "Freely redistributable (BSD license)";
}
bool
PowerSpectrum::initialise(size_t channels, size_t, size_t blockSize)
{
if (channels < getMinChannelCount() ||
channels > getMaxChannelCount()) return false;
m_blockSize = blockSize;
return true;
}
void
PowerSpectrum::reset()
{
}
PowerSpectrum::OutputList
PowerSpectrum::getOutputDescriptors() const
{
OutputList list;
OutputDescriptor d;
d.identifier = "powerspectrum";
d.name = "Power Spectrum";
d.description = "Power values of the frequency spectrum bins calculated from the input signal";
d.unit = "";
d.hasFixedBinCount = true;
if (m_blockSize == 0) {
// Just so as not to return "1". This is the bin count that
// would result from a block size of 1024, which is a likely
// default -- but the host should always set the block size
// before querying the bin count for certain.
d.binCount = 513;
} else {
d.binCount = m_blockSize / 2 + 1;
}
d.hasKnownExtents = false;
d.isQuantized = false;
d.sampleType = OutputDescriptor::OneSamplePerStep;
list.push_back(d);
return list;
}
PowerSpectrum::FeatureSet
PowerSpectrum::process(const float *const *inputBuffers, Vamp::RealTime)
{
FeatureSet fs;
if (m_blockSize == 0) {
cerr << "ERROR: PowerSpectrum::process: Not initialised" << endl;
return fs;
}
size_t n = m_blockSize / 2 + 1;
const float *fbuf = inputBuffers[0];
Feature feature;
feature.hasTimestamp = false;
feature.values.reserve(n); // optional
for (size_t i = 0; i < n; ++i) {
double real = fbuf[i * 2];
double imag = fbuf[i * 2 + 1];
feature.values.push_back(real * real + imag * imag);
}
fs[0].push_back(feature);
return fs;
}
PowerSpectrum::FeatureSet
PowerSpectrum::getRemainingFeatures()
{
return FeatureSet();
}
PowerSpectrum.h
PowerSpectrum::getDescription
std::string getDescription() const
Get a human-readable description for the plugin, typically a line of text that may optionally be disp...
Definition PowerSpectrum.cpp:68
PowerSpectrum::reset
void reset()
Reset the plugin after use, to prepare it for another clean run.
Definition PowerSpectrum.cpp:103
PowerSpectrum::m_blockSize
size_t m_blockSize
Definition PowerSpectrum.h:76
PowerSpectrum::getMaker
std::string getMaker() const
Get the name of the author or vendor of the plugin in human-readable form.
Definition PowerSpectrum.cpp:74
PowerSpectrum::getOutputDescriptors
OutputList getOutputDescriptors() const
Get the outputs of this plugin.
Definition PowerSpectrum.cpp:108
PowerSpectrum::getIdentifier
std::string getIdentifier() const
Get the computer-usable name of the plugin.
Definition PowerSpectrum.cpp:56
PowerSpectrum::getName
std::string getName() const
Get a human-readable name or title of the plugin.
Definition PowerSpectrum.cpp:62
PowerSpectrum::PowerSpectrum
PowerSpectrum(float inputSampleRate)
Definition PowerSpectrum.cpp:45
PowerSpectrum::process
FeatureSet process(const float *const *inputBuffers, Vamp::RealTime timestamp)
Process a single block of input data.
Definition PowerSpectrum.cpp:136
PowerSpectrum::getCopyright
std::string getCopyright() const
Get the copyright statement or licensing summary for the plugin.
Definition PowerSpectrum.cpp:86
PowerSpectrum::getRemainingFeatures
FeatureSet getRemainingFeatures()
After all blocks have been processed, calculate and return any remaining features derived from the co...
Definition PowerSpectrum.cpp:166
PowerSpectrum::getPluginVersion
int getPluginVersion() const
Get the version number of the plugin.
Definition PowerSpectrum.cpp:80
PowerSpectrum::initialise
bool initialise(size_t channels, size_t stepSize, size_t blockSize)
Initialise a plugin to prepare it for use with the given number of input channels,...
Definition PowerSpectrum.cpp:92
PowerSpectrum::~PowerSpectrum
virtual ~PowerSpectrum()
Definition PowerSpectrum.cpp:51
Vamp::Plugin::getMaxChannelCount
virtual size_t getMaxChannelCount() const
Get the maximum supported number of input channels.
Definition vamp-sdk/Plugin.h:204
Vamp::Plugin::Plugin
Plugin(float inputSampleRate)
Definition vamp-sdk/Plugin.h:446
Vamp::Plugin::OutputList
std::vector< OutputDescriptor > OutputList
Definition vamp-sdk/Plugin.h:335
Vamp::Plugin::FeatureSet
std::map< int, FeatureList > FeatureSet
Definition vamp-sdk/Plugin.h:395
Vamp::Plugin::getMinChannelCount
virtual size_t getMinChannelCount() const
Get the minimum supported number of input channels.
Definition vamp-sdk/Plugin.h:199
Vamp::Plugin::Feature
Definition vamp-sdk/Plugin.h:345
Vamp::Plugin::Feature::values
std::vector< float > values
Results for a single sample of this feature.
Definition vamp-sdk/Plugin.h:382
Vamp::Plugin::Feature::hasTimestamp
bool hasTimestamp
True if an output feature has its own timestamp.
Definition vamp-sdk/Plugin.h:352
Vamp::Plugin::OutputDescriptor
Definition vamp-sdk/Plugin.h:207
Vamp::Plugin::OutputDescriptor::sampleType
SampleType sampleType
Positioning in time of the output results.
Definition vamp-sdk/Plugin.h:302
Vamp::Plugin::OutputDescriptor::isQuantized
bool isQuantized
True if the output values are quantized to a particular resolution.
Definition vamp-sdk/Plugin.h:278
Vamp::Plugin::OutputDescriptor::unit
std::string unit
The unit of the output, in human-readable form.
Definition vamp-sdk/Plugin.h:232
Vamp::Plugin::OutputDescriptor::name
std::string name
The human-readable name of the output.
Definition vamp-sdk/Plugin.h:220
Vamp::Plugin::OutputDescriptor::identifier
std::string identifier
The name of the output, in computer-usable form.
Definition vamp-sdk/Plugin.h:214
Vamp::Plugin::OutputDescriptor::hasKnownExtents
bool hasKnownExtents
True if the results in each output bin fall within a fixed numeric range (minimum and maximum values)...
Definition vamp-sdk/Plugin.h:260
Vamp::Plugin::OutputDescriptor::hasFixedBinCount
bool hasFixedBinCount
True if the output has the same number of values per sample for every output sample.
Definition vamp-sdk/Plugin.h:239
Vamp::Plugin::OutputDescriptor::description
std::string description
A human-readable short text describing the output.
Definition vamp-sdk/Plugin.h:227
Vamp::Plugin::OutputDescriptor::binCount
size_t binCount
The number of values per result of the output.
Definition vamp-sdk/Plugin.h:247
Vamp::RealTime
RealTime represents time values to nanosecond precision with accurate arithmetic and frame-rate conve...
Definition vamp-sdk/RealTime.h:67