Mercurial > hg > vamp-plugin-sdk
view examples/PowerSpectrum.cpp @ 390:06988ce35ff0 vh
Initial draft of C API for plugin loading
author | Chris Cannam |
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date | Wed, 20 May 2015 16:12:18 +0100 |
parents | 88ef5ffdbe8d |
children | 7d59dd1ba5de |
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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 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 "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 stepSize, 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 timestamp) { 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(); }