ref: 7f3ccc5e83ab732b4d7b7c3766f25571caff1f8e
parent: ba11e530136b1a17fed742cd423408fa587ea212
author: Paul Brossier <piem@altern.org>
date: Wed May 17 14:16:59 EDT 2006
update pitch method comments update pitch method comments
--- a/src/pitchfcomb.c
+++ b/src/pitchfcomb.c
@@ -17,16 +17,6 @@
*/
-/*
-
- This file was taken from the tuneit project, in the file
- tuneit.c -- Detect fundamental frequency of a sound
- see http://delysid.org/tuneit.html
-
- a fast harmonic comb filter algorithm for pitch tracking
-
-*/
-
#include "aubio_priv.h"
#include "sample.h"
#include "mathutils.h"
--- a/src/pitchfcomb.h
+++ b/src/pitchfcomb.h
@@ -17,6 +17,20 @@
*/
+/** \file
+
+ Pitch detection using a fast harmonic comb filter
+
+ This pitch extraction method implements a fast harmonic comb filter to
+ determine the fundamental frequency of a harmonic sound.
+
+ This file was derived from the tuneit project, written by Mario Lang to
+ detect the fundamental frequency of a sound.
+
+ see http://delysid.org/tuneit.html
+
+*/
+
#ifndef _PITCHFCOMB_H
#define _PITCHFCOMB_H
@@ -24,10 +38,29 @@
extern "C" {#endif
+/** pitch detection object */
typedef struct _aubio_pitchfcomb_t aubio_pitchfcomb_t;
+/** execute pitch detection on an input buffer
+
+ \param p pitch detection object as returned by new_aubio_pitchfcomb
+ \param input input signal window (length as specified at creation time)
+
+*/
smpl_t aubio_pitchfcomb_detect (aubio_pitchfcomb_t *p, fvec_t * input);
+/** creation of the pitch detection object
+
+ \param bufsize size of the input buffer to analyse
+ \param hopsize step size between two consecutive analysis instant
+ \param samplerate sampling rate of the signal
+
+*/
aubio_pitchfcomb_t * new_aubio_pitchfcomb (uint_t bufsize, uint_t hopsize, uint_t samplerate);
+/** deletion of the pitch detection object
+
+ \param p pitch detection object as returned by new_aubio_pitchfcomb
+
+*/
void del_aubio_pitchfcomb (aubio_pitchfcomb_t *p);
--- a/src/pitchmcomb.c
+++ b/src/pitchmcomb.c
@@ -160,7 +160,7 @@
vec_dc_removal(mag); /* dc removal */
vec_alpha_normalise(mag,p->alpha); /* alpha normalisation */
/* skipped */ /* low pass filtering */
- /** \bug: vec_movind_thres writes out of bounds */
+ /** \bug vec_moving_thres may write out of bounds */
vec_adapt_thres(mag,tmp,p->win_post,p->win_pre); /* adaptative threshold */
vec_add(mag,-p->threshold); /* fixed threshold */
{@@ -324,7 +324,7 @@
aubio_pitchmcomb_t * new_aubio_pitchmcomb(uint_t bufsize, uint_t hopsize, uint_t channels, uint_t samplerate) {aubio_pitchmcomb_t * p = AUBIO_NEW(aubio_pitchmcomb_t);
- /** \bug should check if size / 8 > post+pre+1 */
+ /* bug: should check if size / 8 > post+pre+1 */
uint_t i;
uint_t spec_size;
p->spec_partition = 4;
--- a/src/pitchmcomb.h
+++ b/src/pitchmcomb.h
@@ -18,11 +18,20 @@
*/
/** \file
- * spectral pitch detection function
- *
- * \todo check/fix peak picking
- */
+ Pitch detection using multiple-comb filter
+
+ This fundamental frequency estimation algorithm implements spectral
+ flattening, multi-comb filtering and peak histogramming.
+
+ This method was designed by Juan P. Bello and described in:
+
+ Juan-Pablo Bello. ``Towards the Automated Analysis of Simple Polyphonic
+ Music''. PhD thesis, Centre for Digital Music, Queen Mary University of
+ London, London, UK, 2003.
+
+*/
+
#ifndef PITCHMCOMB_H
#define PITCHMCOMB_H
@@ -30,11 +39,31 @@
extern "C" {#endif
+/** pitch detection object */
typedef struct _aubio_pitchmcomb_t aubio_pitchmcomb_t;
+/** execute pitch detection on an input spectral frame
+
+ \param p pitch detection object as returned by new_aubio_pitchmcomb
+ \param fftgrain input signal spectrum as computed by aubio_pvoc_do
+
+*/
smpl_t aubio_pitchmcomb_detect(aubio_pitchmcomb_t * p, cvec_t * fftgrain);
uint_t aubio_pitch_cands(aubio_pitchmcomb_t * p, cvec_t * fftgrain, smpl_t * cands);
+/** creation of the pitch detection object
+
+ \param bufsize size of the input buffer to analyse
+ \param hopsize step size between two consecutive analysis instant
+ \param channels number of channels to analyse
+ \param samplerate sampling rate of the signal
+
+*/
aubio_pitchmcomb_t * new_aubio_pitchmcomb(uint_t bufsize, uint_t hopsize, uint_t channels, uint_t samplerate);
+/** deletion of the pitch detection object
+
+ \param p pitch detection object as returned by new_aubio_pitchfcomb
+
+*/
void del_aubio_pitchmcomb(aubio_pitchmcomb_t *p);
#ifdef __cplusplus
--- a/src/pitchyin.h
+++ b/src/pitchyin.h
@@ -16,15 +16,20 @@
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
-/* This algorithm was developped by A. de Cheveigne and H. Kawahara and
- * published in:
- *
- * de Cheveigné, A., Kawahara, H. (2002) "YIN, a fundamental frequency
- * estimator for speech and music", J. Acoust. Soc. Am. 111, 1917-1930.
- *
- * see http://recherche.ircam.fr/equipes/pcm/pub/people/cheveign.html
- */
+/** \file
+
+ Pitch detection using the YIN algorithm
+
+ This algorithm was developped by A. de Cheveigne and H. Kawahara and
+ published in:
+
+ De Cheveigné, A., Kawahara, H. (2002) "YIN, a fundamental frequency
+ estimator for speech and music", J. Acoust. Soc. Am. 111, 1917-1930.
+
+ see http://recherche.ircam.fr/equipes/pcm/pub/people/cheveign.html
+*/
+
#ifndef PITCHYIN_H
#define PITCHYIN_H
@@ -32,12 +37,35 @@
extern "C" {#endif
+/** compute difference function
+
+ \param input input signal
+ \param yinbuf output buffer to store difference function (half shorter than input)
+
+*/
void aubio_pitchyin_diff(fvec_t * input, fvec_t * yinbuf);
+/** in place computation of the YIN cumulative normalised function
+
+ \param yinbuf input signal (a square difference function), also used to store function
+
+*/
void aubio_pitchyin_getcum(fvec_t * yinbuf);
+/** detect pitch in a YIN function
+
+ \param yinbuf input buffer as computed by aubio_pitchyin_getcum
+
+*/
uint_t aubio_pitchyin_getpitch(fvec_t *yinbuf);
+/** fast implementation of the YIN algorithm
+
+ \param input input signal
+ \param yinbuf input buffer used to compute the YIN function
+ \param tol tolerance parameter for minima selection [default 0.15]
+
+*/
smpl_t aubio_pitchyin_getpitchfast(fvec_t * input, fvec_t *yinbuf, smpl_t tol);
#ifdef __cplusplus
--- a/src/pitchyinfft.c
+++ b/src/pitchyinfft.c
@@ -16,19 +16,6 @@
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
-/* This algorithm was developped by A. de Cheveigne and H. Kawahara and
- * published in:
- *
- * de Cheveigné, A., Kawahara, H. (2002) "YIN, a fundamental frequency
- * estimator for speech and music", J. Acoust. Soc. Am. 111, 1917-1930.
- *
- * see http://recherche.ircam.fr/equipes/pcm/pub/people/cheveign.html
- *
- * This implementation is using an FFT to compute the square difference
- * function, which allows spectral weighting
- *
- */
-
#include "aubio_priv.h"
#include "sample.h"
#include "mathutils.h"
@@ -138,7 +125,7 @@
//return tau+2;
/* 3 point quadratic interpolation */
//return vec_quadint_min(yin,tau,1);
- /* additional check nlikely octave doubling in higher frequencies */
+ /* additional check for (unlikely) octave doubling in higher frequencies */
if (tau>35) {return vec_quadint_min(yin,tau,1)+1;
} else {--- a/src/pitchyinfft.h
+++ b/src/pitchyinfft.h
@@ -16,15 +16,21 @@
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
-/* This algorithm was developped by A. de Cheveigne and H. Kawahara and
- * published in:
- *
- * de Cheveigné, A., Kawahara, H. (2002) "YIN, a fundamental frequency
- * estimator for speech and music", J. Acoust. Soc. Am. 111, 1917-1930.
- *
- * see http://recherche.ircam.fr/equipes/pcm/pub/people/cheveign.html
- */
+/** \file
+
+ Pitch detection using a spectral implementation of the YIN algorithm
+
+ This algorithm was derived from the YIN algorithm (see pitchyin.c). In this
+ implementation, a Fourier transform is used to compute a tapered square
+ difference function, which allows spectral weighting. Because the difference
+ function is tapered, the selection of the period is simplified.
+
+ Paul Brossier, ``Automatic annotation of musical audio for interactive
+ systems'', Chapter 3, Pitch Analysis, PhD thesis, Centre for Digital music,
+ Queen Mary University of London, London, UK, 2003.
+*/
+
#ifndef PITCHYINFFT_H
#define PITCHYINFFT_H
@@ -32,9 +38,22 @@
extern "C" {#endif
+/** pitch detection object */
typedef struct _aubio_pitchyinfft_t aubio_pitchyinfft_t;
+/** execute pitch detection on an input buffer
+
+ \param p pitch detection object as returned by new_aubio_pitchyinfft
+ \param input input signal window (length as specified at creation time)
+ \param tol tolerance parameter for minima selection [default 0.85]
+
+*/
smpl_t aubio_pitchyinfft_detect (aubio_pitchyinfft_t *p, fvec_t * input, smpl_t tol);
+/** creation of the pitch detection object
+
+ \param bufsize size of the input buffer to analyse
+
+*/
aubio_pitchyinfft_t * new_aubio_pitchyinfft (uint_t bufsize);
void del_aubio_pitchyinfft (aubio_pitchyinfft_t *p);