Mercurial > hg > vamp-plugin-sdk
view examples/ZeroCrossing.cpp @ 119:e9b5fb4a6ea3
...
author | cannam |
---|---|
date | Sun, 24 Feb 2008 17:20:30 +0000 |
parents | aa64a46320d4 |
children | 1982246a3902 |
line wrap: on
line source
/* -*- 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 2006 Chris Cannam. 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 "ZeroCrossing.h" using std::string; using std::vector; using std::cerr; using std::endl; ZeroCrossing::ZeroCrossing(float inputSampleRate) : Plugin(inputSampleRate), m_stepSize(0), m_previousSample(0.0f) { } ZeroCrossing::~ZeroCrossing() { } string ZeroCrossing::getIdentifier() const { return "zerocrossing"; } string ZeroCrossing::getName() const { return "Zero Crossings"; } string ZeroCrossing::getDescription() const { return "Detect and count zero crossing points"; } string ZeroCrossing::getMaker() const { return "Vamp SDK Example Plugins"; } int ZeroCrossing::getPluginVersion() const { return 2; } string ZeroCrossing::getCopyright() const { return "Freely redistributable (BSD license)"; } bool ZeroCrossing::initialise(size_t channels, size_t stepSize, size_t blockSize) { if (channels < getMinChannelCount() || channels > getMaxChannelCount()) return false; m_stepSize = std::min(stepSize, blockSize); return true; } void ZeroCrossing::reset() { m_previousSample = 0.0f; } ZeroCrossing::OutputList ZeroCrossing::getOutputDescriptors() const { OutputList list; OutputDescriptor zc; zc.identifier = "counts"; zc.name = "Zero Crossing Counts"; zc.description = "The number of zero crossing points per processing block"; zc.unit = "crossings"; zc.hasFixedBinCount = true; zc.binCount = 1; zc.hasKnownExtents = false; zc.isQuantized = true; zc.quantizeStep = 1.0; zc.sampleType = OutputDescriptor::OneSamplePerStep; list.push_back(zc); zc.identifier = "zerocrossings"; zc.name = "Zero Crossings"; zc.description = "The locations of zero crossing points"; zc.unit = ""; zc.hasFixedBinCount = true; zc.binCount = 0; zc.sampleType = OutputDescriptor::VariableSampleRate; zc.sampleRate = m_inputSampleRate; list.push_back(zc); return list; } ZeroCrossing::FeatureSet ZeroCrossing::process(const float *const *inputBuffers, Vamp::RealTime timestamp) { if (m_stepSize == 0) { cerr << "ERROR: ZeroCrossing::process: " << "ZeroCrossing has not been initialised" << endl; return FeatureSet(); } float prev = m_previousSample; size_t count = 0; FeatureSet returnFeatures; for (size_t i = 0; i < m_stepSize; ++i) { float sample = inputBuffers[0][i]; bool crossing = false; if (sample <= 0.0) { if (prev > 0.0) crossing = true; } else if (sample > 0.0) { if (prev <= 0.0) crossing = true; } if (crossing) { ++count; Feature feature; feature.hasTimestamp = true; feature.timestamp = timestamp + Vamp::RealTime::frame2RealTime(i, (size_t)m_inputSampleRate); returnFeatures[1].push_back(feature); } prev = sample; } m_previousSample = prev; Feature feature; feature.hasTimestamp = false; feature.values.push_back(count); returnFeatures[0].push_back(feature); return returnFeatures; } ZeroCrossing::FeatureSet ZeroCrossing::getRemainingFeatures() { return FeatureSet(); }