b4e64781d84e/code-doc/SpectralCentroid_8cpp_source.html

00001 /* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
cannam@50: 00002
cannam@50: 00003 /*
cannam@50: 00004     Vamp
cannam@50: 00005
cannam@50: 00006     An API for audio analysis and feature extraction plugins.
cannam@50: 00007
cannam@50: 00008     Centre for Digital Music, Queen Mary, University of London.
cannam@50: 00009     Copyright 2006 Chris Cannam.
cannam@50: 00010
cannam@50: 00011     Permission is hereby granted, free of charge, to any person
cannam@50: 00012     obtaining a copy of this software and associated documentation
cannam@50: 00013     files (the "Software"), to deal in the Software without
cannam@50: 00014     restriction, including without limitation the rights to use, copy,
cannam@50: 00015     modify, merge, publish, distribute, sublicense, and/or sell copies
cannam@50: 00016     of the Software, and to permit persons to whom the Software is
cannam@50: 00017     furnished to do so, subject to the following conditions:
cannam@50: 00018
cannam@50: 00019     The above copyright notice and this permission notice shall be
cannam@50: 00020     included in all copies or substantial portions of the Software.
cannam@50: 00021
cannam@50: 00022     THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
cannam@50: 00023     EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
cannam@50: 00024     MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
cannam@50: 00025     NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR
cannam@50: 00026     ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
cannam@50: 00027     CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
cannam@50: 00028     WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
cannam@50: 00029
cannam@50: 00030     Except as contained in this notice, the names of the Centre for
cannam@50: 00031     Digital Music; Queen Mary, University of London; and Chris Cannam
cannam@50: 00032     shall not be used in advertising or otherwise to promote the sale,
cannam@50: 00033     use or other dealings in this Software without prior written
cannam@50: 00034     authorization.
cannam@50: 00035 */
cannam@50: 00036
cannam@50: 00037 #include "SpectralCentroid.h"
cannam@50: 00038
cannam@50: 00039 using std::string;
cannam@50: 00040 using std::vector;
cannam@50: 00041 using std::cerr;
cannam@50: 00042 using std::endl;
cannam@50: 00043
cannam@50: 00044 #include <math.h>
cannam@50: 00045
cannam@50: 00046 #ifdef __SUNPRO_CC
cannam@50: 00047 #include <ieeefp.h>
cannam@50: 00048 #define isinf(x) (!finite(x))
cannam@50: 00049 #endif
cannam@50: 00050
cannam@50: 00051 #ifdef WIN32
cannam@50: 00052 #define isnan(x) false
cannam@50: 00053 #define isinf(x) false
cannam@50: 00054 #endif
cannam@50: 00055
cannam@50: 00056 SpectralCentroid::SpectralCentroid(float inputSampleRate) :
cannam@50: 00057     Plugin(inputSampleRate),
cannam@50: 00058     m_stepSize(0),
cannam@50: 00059     m_blockSize(0)
cannam@50: 00060 {
cannam@50: 00061 }
cannam@50: 00062
cannam@50: 00063 SpectralCentroid::~SpectralCentroid()
cannam@50: 00064 {
cannam@50: 00065 }
cannam@50: 00066
cannam@50: 00067 string
cannam@50: 00068 SpectralCentroid::getIdentifier() const
cannam@50: 00069 {
cannam@50: 00070     return "spectralcentroid";
cannam@50: 00071 }
cannam@50: 00072
cannam@50: 00073 string
cannam@50: 00074 SpectralCentroid::getName() const
cannam@50: 00075 {
cannam@50: 00076     return "Spectral Centroid";
cannam@50: 00077 }
cannam@50: 00078
cannam@50: 00079 string
cannam@50: 00080 SpectralCentroid::getDescription() const
cannam@50: 00081 {
cannam@50: 00082     return "Calculate the centroid frequency of the spectrum of the input signal";
cannam@50: 00083 }
cannam@50: 00084
cannam@50: 00085 string
cannam@50: 00086 SpectralCentroid::getMaker() const
cannam@50: 00087 {
cannam@50: 00088     return "Vamp SDK Example Plugins";
cannam@50: 00089 }
cannam@50: 00090
cannam@50: 00091 int
cannam@50: 00092 SpectralCentroid::getPluginVersion() const
cannam@50: 00093 {
cannam@50: 00094     return 2;
cannam@50: 00095 }
cannam@50: 00096
cannam@50: 00097 string
cannam@50: 00098 SpectralCentroid::getCopyright() const
cannam@50: 00099 {
cannam@50: 00100     return "Freely redistributable (BSD license)";
cannam@50: 00101 }
cannam@50: 00102
cannam@50: 00103 bool
cannam@50: 00104 SpectralCentroid::initialise(size_t channels, size_t stepSize, size_t blockSize)
cannam@50: 00105 {
cannam@50: 00106     if (channels < getMinChannelCount() ||
cannam@50: 00107         channels > getMaxChannelCount()) return false;
cannam@50: 00108
cannam@50: 00109     m_stepSize = stepSize;
cannam@50: 00110     m_blockSize = blockSize;
cannam@50: 00111
cannam@50: 00112     return true;
cannam@50: 00113 }
cannam@50: 00114
cannam@50: 00115 void
cannam@50: 00116 SpectralCentroid::reset()
cannam@50: 00117 {
cannam@50: 00118 }
cannam@50: 00119
cannam@50: 00120 SpectralCentroid::OutputList
cannam@50: 00121 SpectralCentroid::getOutputDescriptors() const
cannam@50: 00122 {
cannam@50: 00123     OutputList list;
cannam@50: 00124
cannam@50: 00125     OutputDescriptor d;
cannam@50: 00126     d.identifier = "logcentroid";
cannam@50: 00127     d.name = "Log Frequency Centroid";
cannam@50: 00128     d.description = "Centroid of the log weighted frequency spectrum";
cannam@50: 00129     d.unit = "Hz";
cannam@50: 00130     d.hasFixedBinCount = true;
cannam@50: 00131     d.binCount = 1;
cannam@50: 00132     d.hasKnownExtents = false;
cannam@50: 00133     d.isQuantized = false;
cannam@50: 00134     d.sampleType = OutputDescriptor::OneSamplePerStep;
cannam@50: 00135     list.push_back(d);
cannam@50: 00136
cannam@50: 00137     d.identifier = "linearcentroid";
cannam@50: 00138     d.name = "Linear Frequency Centroid";
cannam@50: 00139     d.description = "Centroid of the linear frequency spectrum";
cannam@50: 00140     list.push_back(d);
cannam@50: 00141
cannam@50: 00142     return list;
cannam@50: 00143 }
cannam@50: 00144
cannam@50: 00145 SpectralCentroid::FeatureSet
cannam@50: 00146 SpectralCentroid::process(const float *const *inputBuffers, Vamp::RealTime timestamp)
cannam@50: 00147 {
cannam@50: 00148     if (m_stepSize == 0) {
cannam@50: 00149         cerr << "ERROR: SpectralCentroid::process: "
cannam@50: 00150              << "SpectralCentroid has not been initialised"
cannam@50: 00151              << endl;
cannam@50: 00152         return FeatureSet();
cannam@50: 00153     }
cannam@50: 00154
cannam@50: 00155     double numLin = 0.0, numLog = 0.0, denom = 0.0;
cannam@50: 00156
cannam@50: 00157     for (size_t i = 1; i <= m_blockSize/2; ++i) {
cannam@50: 00158         double freq = (double(i) * m_inputSampleRate) / m_blockSize;
cannam@50: 00159         double real = inputBuffers[0][i*2];
cannam@50: 00160         double imag = inputBuffers[0][i*2 + 1];
cannam@50: 00161         double scalemag = sqrt(real * real + imag * imag) / (m_blockSize/2);
cannam@50: 00162         numLin += freq * scalemag;
cannam@50: 00163         numLog += log10f(freq) * scalemag;
cannam@50: 00164         denom += scalemag;
cannam@50: 00165     }
cannam@50: 00166
cannam@50: 00167     FeatureSet returnFeatures;
cannam@50: 00168
cannam@50: 00169     if (denom != 0.0) {
cannam@50: 00170         float centroidLin = float(numLin / denom);
cannam@50: 00171         float centroidLog = powf(10, float(numLog / denom));
cannam@50: 00172
cannam@50: 00173         Feature feature;
cannam@50: 00174         feature.hasTimestamp = false;
cannam@50: 00175
cannam@50: 00176         if (!isnan(centroidLog) && !isinf(centroidLog)) {
cannam@50: 00177             feature.values.push_back(centroidLog);
cannam@50: 00178         }
cannam@50: 00179         returnFeatures[0].push_back(feature);
cannam@50: 00180
cannam@50: 00181         feature.values.clear();
cannam@50: 00182         if (!isnan(centroidLin) && !isinf(centroidLin)) {
cannam@50: 00183             feature.values.push_back(centroidLin);
cannam@50: 00184         }
cannam@50: 00185         returnFeatures[1].push_back(feature);
cannam@50: 00186     }
cannam@50: 00187
cannam@50: 00188     return returnFeatures;
cannam@50: 00189 }
cannam@50: 00190
cannam@50: 00191 SpectralCentroid::FeatureSet
cannam@50: 00192 SpectralCentroid::getRemainingFeatures()
cannam@50: 00193 {
cannam@50: 00194     return FeatureSet();
cannam@50: 00195 }
cannam@50: 00196
cannam@50: