diff constant-q-cpp/cq/CQInverse.h @ 366:5d0a2ebb4d17

Bring dependent libraries in to repo
author Chris Cannam
date Fri, 24 Jun 2016 14:47:45 +0100
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/constant-q-cpp/cq/CQInverse.h	Fri Jun 24 14:47:45 2016 +0100
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+/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
+/*
+    Constant-Q library
+    Copyright (c) 2013-2014 Queen Mary, University of London
+
+    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 AUTHOR 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.
+*/
+
+#ifndef CQINVERSE_H
+#define CQINVERSE_H
+
+#include "CQBase.h"
+#include "CQKernel.h"
+
+class Resampler;
+class FFTReal;
+
+/**
+ * Calculate an inverse constant-Q transform. The input must be the
+ * same representation as returned as output of a \ref ConstantQ
+ * object with the same parameters. The output is a time-domain
+ * signal.
+ *
+ * Note that you cannot perform an inverse transform from the
+ * magnitude-only output of \ref CQSpectrogram; you need the complex
+ * valued data from \ref ConstantQ.
+ *
+ * Our implementation of the Constant-Q transform is not exactly
+ * invertible, and this produces only an approximation of the original
+ * signal (see publications for details).
+ */
+class CQInverse : public CQBase
+{
+public:
+    /**
+     * Construct an inverse Constant-Q transform object using the
+     * given transform parameters.
+     */
+    CQInverse(CQParameters params);
+    virtual ~CQInverse();
+
+    // CQBase methods, see CQBase.h for documentation
+    virtual bool isValid() const { return m_kernel && m_kernel->isValid(); }
+    virtual double getSampleRate() const { return m_sampleRate; }
+    virtual int getBinsPerOctave() const { return m_binsPerOctave; }
+    virtual int getOctaves() const { return m_octaves; }
+    virtual int getTotalBins() const { return m_octaves * m_binsPerOctave; }
+    virtual int getColumnHop() const { return m_p.fftHop / m_p.atomsPerFrame; }
+    virtual int getLatency() const { return m_outputLatency; } 
+    virtual double getMaxFrequency() const { return m_p.maxFrequency; }
+    virtual double getMinFrequency() const; // actual min, not that passed to ctor
+    virtual double getBinFrequency(double bin) const;
+
+    /**
+     * Given a series of constant-Q columns in the form produced by
+     * the \ref ConstantQ class, return a series of time-domain
+     * samples resulting from approximately inverting the constant-Q
+     * transform.
+     */
+    RealSequence process(const ComplexBlock &);
+
+    /**
+     * Return the remaining time-domain samples following the end of
+     * processing.
+     */
+    RealSequence getRemainingOutput();
+
+private:
+    const CQParameters m_inparams;
+    const double m_sampleRate;
+    const double m_maxFrequency;
+    const double m_minFrequency;
+    const int m_binsPerOctave;
+
+    int m_octaves;
+    CQKernel *m_kernel;
+    CQKernel::Properties m_p;
+
+    std::vector<Resampler *> m_upsamplers;
+    std::vector<RealSequence> m_buffers;
+    std::vector<RealSequence> m_olaBufs; // fixed-length, for overlap-add
+    
+    int m_outputLatency;
+
+    FFTReal *m_fft;
+    
+    void initialise();
+    void processOctave(int octave, const ComplexBlock &block);
+    void processOctaveColumn(int octave, const ComplexColumn &column);
+    void overlapAddAndResample(int octave, const RealSequence &);
+    RealSequence drawFromBuffers();
+};
+
+#endif