+/*
+ Copyright (C) 2003-2009 Paul Brossier <piem@aubio.org>
+
+ This file is part of aubio.
+
+ aubio is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ aubio is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with aubio. If not, see <http://www.gnu.org/licenses/>.
+
+*/
+
+/** @file
+ * various math functions
+ */
+
+#ifndef MUSICUTILS_H
+#define MUSICUTILS_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/** create window
+
+ References:
+
+ - <a href="http://en.wikipedia.org/wiki/Window_function">Window
+function</a> on Wikipedia
+ - Amalia de Götzen, Nicolas Bernardini, and Daniel Arfib. Traditional (?)
+implementations of a phase vocoder: the tricks of the trade. In Proceedings of
+the International Conference on Digital Audio Effects (DAFx-00), pages 37–44,
+Uni- versity of Verona, Italy, 2000.
+ (<a href="http://profs.sci.univr.it/%7Edafx/Final-Papers/ps/Bernardini.ps.gz">
+ ps.gz</a>)
+
+*/
+fvec_t *new_aubio_window (char_t * window_type, uint_t size);
+
+/** compute the principal argument
+
+ This function maps the input phase to its corresponding value wrapped in the
+range \f$ [-\pi, \pi] \f$.
+
+ \param phase unwrapped phase to map to the unit circle
+
+ \return equivalent phase wrapped to the unit circle
+
+*/
+smpl_t aubio_unwrap2pi (smpl_t phase);
+
+/** convert frequency bin to midi value */
+smpl_t aubio_bintomidi (smpl_t bin, smpl_t samplerate, smpl_t fftsize);
+
+/** convert midi value to frequency bin */
+smpl_t aubio_miditobin (smpl_t midi, smpl_t samplerate, smpl_t fftsize);
+
+/** convert frequency bin to frequency (Hz) */
+smpl_t aubio_bintofreq (smpl_t bin, smpl_t samplerate, smpl_t fftsize);
+
+/** convert frequency (Hz) to frequency bin */
+smpl_t aubio_freqtobin (smpl_t freq, smpl_t samplerate, smpl_t fftsize);
+
+/** convert frequency (Hz) to midi value (0-128) */
+smpl_t aubio_freqtomidi (smpl_t freq);
+
+/** convert midi value (0-128) to frequency (Hz) */
+smpl_t aubio_miditofreq (smpl_t midi);
+
+/** clean up cached memory at the end of program
+
+ This function should be used at the end of programs to purge all cached
+ memory. So far it is only useful to clean FFTW's cache.
+
+*/
+void aubio_cleanup (void);
+
+/** zero-crossing rate (ZCR)
+
+ The zero-crossing rate is the number of times a signal changes sign,
+ divided by the length of this signal.
+
+ \param v vector to compute ZCR from
+
+ \return zero-crossing rate of v
+
+*/
+smpl_t aubio_zero_crossing_rate (fvec_t * v);
+
+/** compute sound pressure level (SPL) in dB
+
+ This quantity is often wrongly called 'loudness'.
+
+ \param v vector to compute dB SPL from
+
+ \return level of v in dB SPL
+
+*/
+smpl_t aubio_db_spl (fvec_t * v);
+
+/** check if buffer level in dB SPL is under a given threshold
+
+ \param v vector to get level from
+ \param threshold threshold in dB SPL
+
+ \return 0 if level is under the given threshold, 1 otherwise
+
+*/
+uint_t aubio_silence_detection (fvec_t * v, smpl_t threshold);
+
+/** get buffer level if level >= threshold, 1. otherwise
+
+ \param v vector to get level from
+ \param threshold threshold in dB SPL
+
+ \return level in dB SPL if level >= threshold, 1. otherwise
+
+*/
+smpl_t aubio_level_detection (fvec_t * v, smpl_t threshold);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
+
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