3c430ef1ed66/code-docs/SpectralCentroid_8cpp_source.html

00001 /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
Chris@1: 00002
Chris@1: 00003 /*
Chris@1: 00004     Vamp
Chris@1: 00005
Chris@1: 00006     An API for audio analysis and feature extraction plugins.
Chris@1: 00007
Chris@1: 00008     Centre for Digital Music, Queen Mary, University of London.
Chris@1: 00009     Copyright 2006 Chris Cannam.
Chris@1: 00010
Chris@1: 00011     Permission is hereby granted, free of charge, to any person
Chris@1: 00012     obtaining a copy of this software and associated documentation
Chris@1: 00013     files (the "Software"), to deal in the Software without
Chris@1: 00014     restriction, including without limitation the rights to use, copy,
Chris@1: 00015     modify, merge, publish, distribute, sublicense, and/or sell copies
Chris@1: 00016     of the Software, and to permit persons to whom the Software is
Chris@1: 00017     furnished to do so, subject to the following conditions:
Chris@1: 00018
Chris@1: 00019     The above copyright notice and this permission notice shall be
Chris@1: 00020     included in all copies or substantial portions of the Software.
Chris@1: 00021
Chris@1: 00022     THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
Chris@1: 00023     EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
Chris@1: 00024     MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
Chris@1: 00025     NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR
Chris@1: 00026     ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
Chris@1: 00027     CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
Chris@1: 00028     WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
Chris@1: 00029
Chris@1: 00030     Except as contained in this notice, the names of the Centre for
Chris@1: 00031     Digital Music; Queen Mary, University of London; and Chris Cannam
Chris@1: 00032     shall not be used in advertising or otherwise to promote the sale,
Chris@1: 00033     use or other dealings in this Software without prior written
Chris@1: 00034     authorization.
Chris@1: 00035 */
Chris@1: 00036
Chris@1: 00037 #include "SpectralCentroid.h"
Chris@1: 00038
Chris@1: 00039 using std::string;
Chris@1: 00040 using std::vector;
Chris@1: 00041 using std::cerr;
Chris@1: 00042 using std::endl;
Chris@1: 00043
Chris@1: 00044 #include <math.h>
Chris@1: 00045
Chris@1: 00046 #ifdef __SUNPRO_CC
Chris@1: 00047 #include <ieeefp.h>
Chris@1: 00048 #define isinf(x) (!finite(x))
Chris@1: 00049 #endif
Chris@1: 00050
Chris@1: 00051 #ifdef WIN32
Chris@1: 00052 #define isnan(x) false
Chris@1: 00053 #define isinf(x) false
Chris@1: 00054 #endif
Chris@1: 00055
Chris@1: 00056 SpectralCentroid::SpectralCentroid(float inputSampleRate) :
Chris@1: 00057     Plugin(inputSampleRate),
Chris@1: 00058     m_stepSize(0),
Chris@1: 00059     m_blockSize(0)
Chris@1: 00060 {
Chris@1: 00061 }
Chris@1: 00062
Chris@1: 00063 SpectralCentroid::~SpectralCentroid()
Chris@1: 00064 {
Chris@1: 00065 }
Chris@1: 00066
Chris@1: 00067 string
Chris@1: 00068 SpectralCentroid::getIdentifier() const
Chris@1: 00069 {
Chris@1: 00070     return "spectralcentroid";
Chris@1: 00071 }
Chris@1: 00072
Chris@1: 00073 string
Chris@1: 00074 SpectralCentroid::getName() const
Chris@1: 00075 {
Chris@1: 00076     return "Spectral Centroid";
Chris@1: 00077 }
Chris@1: 00078
Chris@1: 00079 string
Chris@1: 00080 SpectralCentroid::getDescription() const
Chris@1: 00081 {
Chris@1: 00082     return "Calculate the centroid frequency of the spectrum of the input signal";
Chris@1: 00083 }
Chris@1: 00084
Chris@1: 00085 string
Chris@1: 00086 SpectralCentroid::getMaker() const
Chris@1: 00087 {
Chris@1: 00088     return "Vamp SDK Example Plugins";
Chris@1: 00089 }
Chris@1: 00090
Chris@1: 00091 int
Chris@1: 00092 SpectralCentroid::getPluginVersion() const
Chris@1: 00093 {
Chris@1: 00094     return 2;
Chris@1: 00095 }
Chris@1: 00096
Chris@1: 00097 string
Chris@1: 00098 SpectralCentroid::getCopyright() const
Chris@1: 00099 {
Chris@1: 00100     return "Freely redistributable (BSD license)";
Chris@1: 00101 }
Chris@1: 00102
Chris@1: 00103 bool
Chris@1: 00104 SpectralCentroid::initialise(size_t channels, size_t stepSize, size_t blockSize)
Chris@1: 00105 {
Chris@1: 00106     if (channels < getMinChannelCount() ||
Chris@1: 00107         channels > getMaxChannelCount()) return false;
Chris@1: 00108
Chris@1: 00109     m_stepSize = stepSize;
Chris@1: 00110     m_blockSize = blockSize;
Chris@1: 00111
Chris@1: 00112     return true;
Chris@1: 00113 }
Chris@1: 00114
Chris@1: 00115 void
Chris@1: 00116 SpectralCentroid::reset()
Chris@1: 00117 {
Chris@1: 00118 }
Chris@1: 00119
Chris@1: 00120 SpectralCentroid::OutputList
Chris@1: 00121 SpectralCentroid::getOutputDescriptors() const
Chris@1: 00122 {
Chris@1: 00123     OutputList list;
Chris@1: 00124
Chris@1: 00125     OutputDescriptor d;
Chris@1: 00126     d.identifier = "logcentroid";
Chris@1: 00127     d.name = "Log Frequency Centroid";
Chris@1: 00128     d.description = "Centroid of the log weighted frequency spectrum";
Chris@1: 00129     d.unit = "Hz";
Chris@1: 00130     d.hasFixedBinCount = true;
Chris@1: 00131     d.binCount = 1;
Chris@1: 00132     d.hasKnownExtents = false;
Chris@1: 00133     d.isQuantized = false;
Chris@1: 00134     d.sampleType = OutputDescriptor::OneSamplePerStep;
Chris@1: 00135     list.push_back(d);
Chris@1: 00136
Chris@1: 00137     d.identifier = "linearcentroid";
Chris@1: 00138     d.name = "Linear Frequency Centroid";
Chris@1: 00139     d.description = "Centroid of the linear frequency spectrum";
Chris@1: 00140     list.push_back(d);
Chris@1: 00141
Chris@1: 00142     return list;
Chris@1: 00143 }
Chris@1: 00144
Chris@1: 00145 SpectralCentroid::FeatureSet
Chris@1: 00146 SpectralCentroid::process(const float *const *inputBuffers, Vamp::RealTime timestamp)
Chris@1: 00147 {
Chris@1: 00148     if (m_stepSize == 0) {
Chris@1: 00149         cerr << "ERROR: SpectralCentroid::process: "
Chris@1: 00150              << "SpectralCentroid has not been initialised"
Chris@1: 00151              << endl;
Chris@1: 00152         return FeatureSet();
Chris@1: 00153     }
Chris@1: 00154
Chris@1: 00155     double numLin = 0.0, numLog = 0.0, denom = 0.0;
Chris@1: 00156
Chris@1: 00157     for (size_t i = 1; i <= m_blockSize/2; ++i) {
Chris@1: 00158         double freq = (double(i) * m_inputSampleRate) / m_blockSize;
Chris@1: 00159         double real = inputBuffers[0][i*2];
Chris@1: 00160         double imag = inputBuffers[0][i*2 + 1];
Chris@1: 00161         double scalemag = sqrt(real * real + imag * imag) / (m_blockSize/2);
Chris@1: 00162         numLin += freq * scalemag;
Chris@1: 00163         numLog += log10f(freq) * scalemag;
Chris@1: 00164         denom += scalemag;
Chris@1: 00165     }
Chris@1: 00166
Chris@1: 00167     FeatureSet returnFeatures;
Chris@1: 00168
Chris@1: 00169     if (denom != 0.0) {
Chris@1: 00170         float centroidLin = float(numLin / denom);
Chris@1: 00171         float centroidLog = powf(10, float(numLog / denom));
Chris@1: 00172
Chris@1: 00173         Feature feature;
Chris@1: 00174         feature.hasTimestamp = false;
Chris@1: 00175
Chris@1: 00176         if (!isnan(centroidLog) && !isinf(centroidLog)) {
Chris@1: 00177             feature.values.push_back(centroidLog);
Chris@1: 00178         }
Chris@1: 00179         returnFeatures[0].push_back(feature);
Chris@1: 00180
Chris@1: 00181         feature.values.clear();
Chris@1: 00182         if (!isnan(centroidLin) && !isinf(centroidLin)) {
Chris@1: 00183             feature.values.push_back(centroidLin);
Chris@1: 00184         }
Chris@1: 00185         returnFeatures[1].push_back(feature);
Chris@1: 00186     }
Chris@1: 00187
Chris@1: 00188     return returnFeatures;
Chris@1: 00189 }
Chris@1: 00190
Chris@1: 00191 SpectralCentroid::FeatureSet
Chris@1: 00192 SpectralCentroid::getRemainingFeatures()
Chris@1: 00193 {
Chris@1: 00194     return FeatureSet();
Chris@1: 00195 }
Chris@1: 00196
Chris@1: