From: Paul Brossier Date: Tue, 29 Sep 2009 05:43:12 +0000 (+0200) Subject: src/temporal: revamp filter object, clarify API for A- and C-weighting filters, X-Git-Tag: bzr2git~258 X-Git-Url: http://git.tremily.us/?a=commitdiff_plain;h=a4364b83d213f0c725b47bacbea5bfa39f798f91;p=aubio.git src/temporal: revamp filter object, clarify API for A- and C-weighting filters, add coefficients for 8000 16000 22050 44100 96000 192000, improve documentation, remove unneeded filter_priv.h, add A and C weighting tests. --- diff --git a/src/Makefile.am b/src/Makefile.am index cb89ee44..f29c5591 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -1,6 +1,5 @@ noinst_HEADERS = \ - aubio_priv.h \ - temporal/filter_priv.h + aubio_priv.h nobase_pkginclude_HEADERS = \ aubio.h \ diff --git a/src/pitch/pitchdetection.c b/src/pitch/pitchdetection.c index 23081d90..51e86a09 100644 --- a/src/pitch/pitchdetection.c +++ b/src/pitch/pitchdetection.c @@ -19,6 +19,7 @@ #include "aubio_priv.h" #include "fvec.h" #include "cvec.h" +#include "lvec.h" #include "spectral/phasevoc.h" #include "mathutils.h" #include "temporal/filter.h" @@ -103,7 +104,7 @@ aubio_pitchdetection_t * new_aubio_pitchdetection(uint_t bufsize, p->pv = new_aubio_pvoc(bufsize, hopsize, channels); p->fftgrain = new_cvec(bufsize, channels); p->mcomb = new_aubio_pitchmcomb(bufsize,hopsize,channels,samplerate); - p->filter = new_aubio_cdsgn_filter(samplerate, channels); + p->filter = new_aubio_filter_cdsgn (samplerate, channels); p->callback = aubio_pitchdetection_mcomb; break; case aubio_pitch_fcomb: diff --git a/src/temporal/adesign.c b/src/temporal/adesign.c index 8b6fd82d..800f2cd5 100644 --- a/src/temporal/adesign.c +++ b/src/temporal/adesign.c @@ -1,58 +1,160 @@ /* - Copyright (C) 2003-2007 Paul Brossier - This program 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 2 of the License, or - (at your option) any later version. + Copyright (C) 2003-2009 Paul Brossier - This program 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. + This file is part of aubio. - You should have received a copy of the GNU General Public License - along with this program; if not, write to the Free Software - Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + 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 . +*/ #include "aubio_priv.h" #include "types.h" #include "fvec.h" +#include "lvec.h" #include "temporal/filter.h" -#include "temporal/filter_priv.h" #include "temporal/adesign.h" -aubio_filter_t * new_aubio_adsgn_filter(uint_t samplerate, uint_t channels) { - aubio_filter_t * f = new_aubio_filter(samplerate, 7, channels); - lsmp_t * a = f->a->data[0]; - lsmp_t * b = f->b->data[0]; - /* uint_t l; */ - /* for now, 44100, adsgn */ - a[0] = 1.00000000000000000000000000000000000000000000000000000; - a[1] = -4.01957618111583236952810693765059113502502441406250000; - a[2] = 6.18940644292069386267485242569819092750549316406250000; - a[3] = -4.45319890354411640487342083360999822616577148437500000; - a[4] = 1.42084294962187751565352300531230866909027099609375000; - a[5] = -0.14182547383030480458998567883099894970655441284179688; - a[6] = 0.00435117723349511334451911181986361043527722358703613; - b[0] = 0.25574112520425740235907596797915175557136535644531250; - b[1] = -0.51148225040851391653973223583307117223739624023437500; - b[2] = -0.25574112520426162120656954357400536537170410156250000; - b[3] = 1.02296450081703405032840237254276871681213378906250000; - b[4] = -0.25574112520426051098354491841746494174003601074218750; - b[5] = -0.51148225040851369449512731080176308751106262207031250; - b[6] = 0.25574112520425729133677350546349771320819854736328125; - /* DBG: filter coeffs at creation time */ - /* - for (l=0; lorder; l++){ - AUBIO_DBG("a[%d]=\t%1.16f\tb[%d]=\t%1.16f\n",l,a[l],l,b[l]); +void aubio_filter_set_adsgn (aubio_filter_t * f) { + + uint_t samplerate = aubio_filter_get_samplerate (f); + lvec_t *bs = aubio_filter_get_feedforward (f); + lvec_t *as = aubio_filter_get_feedback (f); + lsmp_t *b = bs->data[0], *a = as->data[0]; + uint_t order = aubio_filter_get_order (f); + + if ( order != 7 ) { + AUBIO_ERROR ( "order of A-weighting filter must be 7, not %d\n", order ); + return; + } + + /* select coefficients according to sampling frequency */ + switch ( samplerate ) { + + case 8000: + b[0] = 6.306209468238731519207362907764036208391189575195312500e-01; + b[1] = -1.261241893647746525886077506584115326404571533203125000e+00; + b[2] = -6.306209468238730408984338282607495784759521484375000000e-01; + b[3] = 2.522483787295493051772155013168230652809143066406250000e+00; + b[4] = -6.306209468238730408984338282607495784759521484375000000e-01; + b[5] = -1.261241893647746525886077506584115326404571533203125000e+00; + b[6] = 6.306209468238731519207362907764036208391189575195312500e-01; + a[0] = 1.000000000000000000000000000000000000000000000000000000e+00; + a[1] = -2.128467193009123015201566886389628052711486816406250000e+00; + a[2] = 2.948668980101234460278192273108288645744323730468750000e-01; + a[3] = 1.824183830735050637628091863007284700870513916015625000e+00; + a[4] = -8.056628943119792385374466903158463537693023681640625000e-01; + a[5] = -3.947497982842933517133587884018197655677795410156250000e-01; + a[6] = 2.098548546080332977137317129745497368276119232177734375e-01; + break; + + case 16000: + b[0] = 5.314898298235570806014038680586963891983032226562500000e-01; + b[1] = -1.062979659647114161202807736117392778396606445312500000e+00; + b[2] = -5.314898298235570806014038680586963891983032226562500000e-01; + b[3] = 2.125959319294228322405615472234785556793212890625000000e+00; + b[4] = -5.314898298235570806014038680586963891983032226562500000e-01; + b[5] = -1.062979659647114161202807736117392778396606445312500000e+00; + b[6] = 5.314898298235570806014038680586963891983032226562500000e-01; + a[0] = 1.000000000000000000000000000000000000000000000000000000e+00; + a[1] = -2.867832572992162987191022693878039717674255371093750000e+00; + a[2] = 2.221144410202312347024644623161293566226959228515625000e+00; + a[3] = 4.552683347886614662058946123579517006874084472656250000e-01; + a[4] = -9.833868636162828025248927588108927011489868164062500000e-01; + a[5] = 5.592994142413361402521587706360151059925556182861328125e-02; + a[6] = 1.188781038285612462468421313133148942142724990844726562e-01; + break; + + case 22050: + b[0] = 4.492998504299193784916610638902056962251663208007812500e-01; + b[1] = -8.985997008598388680056245902960654348134994506835937500e-01; + b[2] = -4.492998504299192674693586013745516538619995117187500000e-01; + b[3] = 1.797199401719677958055854105623438954353332519531250000e+00; + b[4] = -4.492998504299192674693586013745516538619995117187500000e-01; + b[5] = -8.985997008598388680056245902960654348134994506835937500e-01; + b[6] = 4.492998504299193784916610638902056962251663208007812500e-01; + a[0] = 1.000000000000000000000000000000000000000000000000000000e+00; + a[1] = -3.229078805225074955131958631682209670543670654296875000e+00; + a[2] = 3.354494881236033787530459449044428765773773193359375000e+00; + a[3] = -7.317843680657351024265722116979304701089859008789062500e-01; + a[4] = -6.271627581807257545420952737913466989994049072265625000e-01; + a[5] = 1.772142005020879151899748649157118052244186401367187500e-01; + a[6] = 5.631716697383508385410522123493137769401073455810546875e-02; + break; + + case 44100: + b[0] = 2.55741125204257513381378430494805797934532165527343750e-01; + b[1] = -5.114822504085150267627568609896115958690643310546875000e-01; + b[2] = -2.557411252042575133813784304948057979345321655273437500e-01; + b[3] = 1.022964500817030053525513721979223191738128662109375000e+00; + b[4] = -2.557411252042575133813784304948057979345321655273437500e-01; + b[5] = -5.114822504085150267627568609896115958690643310546875000e-01; + b[6] = 2.557411252042575133813784304948057979345321655273437500e-01; + a[0] = 1.000000000000000000000000000000000000000000000000000000e+00; + a[1] = -4.019576181115832369528106937650591135025024414062500000e+00; + a[2] = 6.189406442920693862674852425698190927505493164062500000e+00; + a[3] = -4.453198903544116404873420833609998226165771484375000000e+00; + a[4] = 1.420842949621876627475103305187076330184936523437500000e+00; + a[5] = -1.418254738303044160119270600262098014354705810546875000e-01; + a[6] = 4.351177233495117681327801761881346465088427066802978516e-03; + + case 96000: + b[0] = 9.951898975972744976203898659150581806898117065429687500e-02; + b[1] = -1.990379795194548995240779731830116361379623413085937500e-01; + b[2] = -9.951898975972744976203898659150581806898117065429687500e-02; + b[3] = 3.980759590389097990481559463660232722759246826171875000e-01; + b[4] = -9.951898975972744976203898659150581806898117065429687500e-02; + b[5] = -1.990379795194548995240779731830116361379623413085937500e-01; + b[6] = 9.951898975972744976203898659150581806898117065429687500e-02; + a[0] = 1.000000000000000000000000000000000000000000000000000000e+00; + a[1] = -4.802203044225376693532325589330866932868957519531250000e+00; + a[2] = 9.401807218627226347962277941405773162841796875000000000e+00; + a[3] = -9.566143943569164420637207513209432363510131835937500000e+00; + a[4] = 5.309775930392619081032989925006404519081115722656250000e+00; + a[5] = -1.517333360452622237346531619550660252571105957031250000e+00; + a[6] = 1.740971994228911745583587844521389342844486236572265625e-01; + break; + + case 192000: + b[0] = 3.433213424548713782469278044118254911154508590698242188e-02; + b[1] = -6.866426849097426177159775306790834292769432067871093750e-02; + b[2] = -3.433213424548714476358668434841092675924301147460937500e-02; + b[3] = 1.373285369819485235431955061358166858553886413574218750e-01; + b[4] = -3.433213424548714476358668434841092675924301147460937500e-02; + b[5] = -6.866426849097426177159775306790834292769432067871093750e-02; + b[6] = 3.433213424548713782469278044118254911154508590698242188e-02; + a[0] = 1.000000000000000000000000000000000000000000000000000000e+00; + a[1] = -5.305923689674640009172890131594613194465637207031250000e+00; + a[2] = 1.165952437466175695135461864992976188659667968750000000e+01; + a[3] = -1.357560092700591525272102444432675838470458984375000000e+01; + a[4] = 8.828906932824192921316353022120893001556396484375000000e+00; + a[5] = -3.039490120988216581565666274400427937507629394531250000e+00; + a[6] = 4.325834301870381537469256727490574121475219726562500000e-01; + break; + + default: + AUBIO_ERROR ( "sampling rate of A-weighting filter is %d, should be one of\ + 8000, 16000, 22050, 44100, 96000, 192000.\n", samplerate ); + break; + } - */ - f->a->data[0] = a; - f->b->data[0] = b; + +} + +aubio_filter_t * new_aubio_filter_adsgn (uint_t samplerate, uint_t channels) { + aubio_filter_t * f = new_aubio_filter (samplerate, 7, channels); + aubio_filter_set_adsgn (f); return f; } diff --git a/src/temporal/adesign.h b/src/temporal/adesign.h index 867630c8..1f621cb4 100644 --- a/src/temporal/adesign.h +++ b/src/temporal/adesign.h @@ -1,19 +1,20 @@ /* - Copyright (C) 2003-2007 Paul Brossier + Copyright (C) 2003-2009 Paul Brossier - This program 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 2 of the License, or - (at your option) any later version. + This file is part of aubio. - This program 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. + 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. - You should have received a copy of the GNU General Public License - along with this program; if not, write to the Free Software - Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + 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 . */ @@ -22,9 +23,30 @@ /** \file - Create a new A-design filter - - This file creates an IIR filter object with A-design coefficients. + Create an A-weighting filter + + This file creates an A-weighting digital filter, which reduces low and high + frequencies and enhance the middle ones to reflect the ability of the human + hearing. + + The implementation is based on the following standard: + + - IEC/CD 1672: Electroacoustics-Sound Level Meters, IEC, Geneva, Nov. 1996, + for A- and C-weighting filters. + + See also: + + - A-Weighting on + Wikipedia + - Weighting filter on + Wikipedia + - Christophe + Couvreur's 'octave' toolbox + + The coefficients in this file have been computed using Christophe Couvreur's + scripts in octave 3.0 (debian package 1:3.0.5-6+b2 with octave-signal + 1.0.9-1+b1 on i386), with 
 [b, a] = adsign(1/Fs)
for various + sampling frequencies. */ @@ -34,16 +56,21 @@ extern "C" { /** create new A-design filter - \param samplerate sampling-rate of the signal to filter + \param samplerate sampling frequency of the signal to filter. Should be one of + 8000, 16000, 22050, 44100, 96000, 192000. \param channels number of channels to allocate + \return a new filter object + */ -aubio_filter_t * new_aubio_adsgn_filter(uint_t samplerate, uint_t channels); +aubio_filter_t * new_aubio_filter_adsgn (uint_t samplerate, uint_t channels); -/** filter input vector (in-place) */ -#define aubio_adsgn_filter_do aubio_filter_do -/** delete a-design filter object */ -#define del_aubio_adsgn_filter del_aubio_filter +/** set feedback and feedforward coefficients of a A-weighting filter + + \param f filter object to get coefficients from + +*/ +void aubio_filter_set_adsgn (aubio_filter_t *f); #ifdef __cplusplus } diff --git a/src/temporal/cdesign.c b/src/temporal/cdesign.c index 7f303ac1..ee4c7a0d 100644 --- a/src/temporal/cdesign.c +++ b/src/temporal/cdesign.c @@ -1,54 +1,136 @@ /* - Copyright (C) 2003-2007 Paul Brossier + Copyright (C) 2003-2009 Paul Brossier - This program 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 2 of the License, or - (at your option) any later version. + This file is part of aubio. - This program 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. + 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. - You should have received a copy of the GNU General Public License - along with this program; if not, write to the Free Software - Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + 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 . +*/ #include "aubio_priv.h" #include "types.h" #include "fvec.h" +#include "lvec.h" #include "temporal/filter.h" -#include "temporal/filter_priv.h" -#include "temporal/adesign.h" +#include "temporal/cdesign.h" -aubio_filter_t * new_aubio_cdsgn_filter(uint_t samplerate, uint_t channels) { - aubio_filter_t * f = new_aubio_filter(samplerate, 5, channels); - lsmp_t * a = f->a->data[0]; - lsmp_t * b = f->b->data[0]; - /* uint_t l; */ - /* for now, 44100, cdsgn */ - a[0] = 1.000000000000000000000000000000000000000000000000000000000000; - a[1] = -2.134674963687040794013682898366823792457580566406250000000000; - a[2] = 1.279333533236063358273781886964570730924606323242187500000000; - a[3] = -0.149559846089396208945743182994192466139793395996093750000000; - a[4] = 0.004908700174624848651394604104325480875559151172637939453125; - b[0] = 0.217008561949218803377448239189106971025466918945312500000000; - b[1] = -0.000000000000000222044604925031308084726333618164062500000000; - b[2] = -0.434017123898438272888711253472138196229934692382812500000000; - b[3] = 0.000000000000000402455846426619245903566479682922363281250000; - b[4] = 0.217008561949218969910901932962588034570217132568359375000000; - /* DBG: filter coeffs at creation time */ - /* - for (l=0; lorder; l++){ - AUBIO_DBG("a[%d]=\t%1.16f\tb[%d]=\t%1.16f\n",l,a[l],l,b[l]); +void aubio_filter_set_cdsgn (aubio_filter_t * f) { + + uint_t samplerate = aubio_filter_get_samplerate (f); + lvec_t * bs = aubio_filter_get_feedforward (f); + lvec_t * as = aubio_filter_get_feedback (f); + lsmp_t *b = bs->data[0], *a = as->data[0]; + uint_t order = aubio_filter_get_order (f); + + if ( order != 5 ) { + AUBIO_ERROR ( "order of C-weighting filter must be 5, not %d\n", order ); + return; } - */ - f->a->data[0] = a; - f->b->data[0] = b; + + /* select coefficients according to sampling frequency */ + switch ( samplerate ) { + + case 8000: + b[0] = 6.782173932405135552414776611840352416038513183593750000e-01; + b[1] = 0.000000000000000000000000000000000000000000000000000000e+00; + b[2] = -1.356434786481027110482955322368070483207702636718750000e+00; + b[3] = 0.000000000000000000000000000000000000000000000000000000e+00; + b[4] = 6.782173932405135552414776611840352416038513183593750000e-01; + a[0] = 1.000000000000000000000000000000000000000000000000000000e+00; + a[1] = -6.589092811505605773447769024642184376716613769531250000e-01; + a[2] = -1.179445664897062595599663836765103042125701904296875000e+00; + a[3] = 4.243329729632123736848825501510873436927795410156250000e-01; + a[4] = 4.147270002091348328754349950031610205769538879394531250e-01; + break; + + case 16000: + b[0] = 4.971057193673903418229542694461997598409652709960937500e-01; + b[1] = 0.000000000000000000000000000000000000000000000000000000e+00; + b[2] = -9.942114387347806836459085388923995196819305419921875000e-01; + b[3] = 0.000000000000000000000000000000000000000000000000000000e+00; + b[4] = 4.971057193673903418229542694461997598409652709960937500e-01; + a[0] = 1.000000000000000000000000000000000000000000000000000000e+00; + a[1] = -1.162322939286873690889478893950581550598144531250000000e+00; + a[2] = -4.771961355734982701548574368644040077924728393554687500e-01; + a[3] = 4.736145114694704227886745684372726827859878540039062500e-01; + a[4] = 1.660337524309875301131711466950946487486362457275390625e-01; + break; + + case 22050: + b[0] = 4.033381299002754549754001800465630367398262023925781250e-01; + b[1] = 0.000000000000000000000000000000000000000000000000000000e+00; + b[2] = -8.066762598005509099508003600931260734796524047851562500e-01; + b[3] = 0.000000000000000000000000000000000000000000000000000000e+00; + b[4] = 4.033381299002754549754001800465630367398262023925781250e-01; + a[0] = 1.000000000000000000000000000000000000000000000000000000e+00; + a[1] = -1.449545371157945350404361306573264300823211669921875000e+00; + a[2] = -1.030104190885922088583015465701464563608169555664062500e-02; + a[3] = 3.881857047554073680828423675848171114921569824218750000e-01; + a[4] = 7.171589940116777917022972133054281584918498992919921875e-02; + break; + + case 44100: + b[0] = 2.170085619492190254220531642204150557518005371093750000e-01; + b[1] = 0.000000000000000000000000000000000000000000000000000000e+00; + b[2] = -4.340171238984380508441063284408301115036010742187500000e-01; + b[3] = 0.000000000000000000000000000000000000000000000000000000e+00; + b[4] = 2.170085619492190254220531642204150557518005371093750000e-01; + a[0] = 1.000000000000000000000000000000000000000000000000000000e+00; + a[1] = -2.134674963687040794013682898366823792457580566406250000e+00; + a[2] = 1.279333533236062692139967111870646476745605468750000000e+00; + a[3] = -1.495598460893957093453821016737492755055427551269531250e-01; + a[4] = 4.908700174624683852664386307651511742733418941497802734e-03; + break; + + case 96000: + b[0] = 8.182864044979756834585771230194950476288795471191406250e-02; + b[1] = 0.000000000000000000000000000000000000000000000000000000e+00; + b[2] = -1.636572808995951366917154246038990095257759094238281250e-01; + b[3] = 0.000000000000000000000000000000000000000000000000000000e+00; + b[4] = 8.182864044979756834585771230194950476288795471191406250e-02; + a[0] = 1.000000000000000000000000000000000000000000000000000000e+00; + a[1] = -2.856378516857566829401093855267390608787536621093750000e+00; + a[2] = 2.897640237559524045707348705036565661430358886718750000e+00; + a[3] = -1.225265958339703198376469117647502571344375610351562500e+00; + a[4] = 1.840048283551226071530493300087982788681983947753906250e-01; + break; + + case 192000: + b[0] = 2.784755468532278815940728122768632601946592330932617188e-02; + b[1] = 0.000000000000000000000000000000000000000000000000000000e+00; + b[2] = -5.569510937064557631881456245537265203893184661865234375e-02; + b[3] = 0.000000000000000000000000000000000000000000000000000000e+00; + b[4] = 2.784755468532278815940728122768632601946592330932617188e-02; + a[0] = 1.000000000000000000000000000000000000000000000000000000e+00; + a[1] = -3.333298856144166322224009491037577390670776367187500000e+00; + a[2] = 4.111467536240339448738723149290308356285095214843750000e+00; + a[3] = -2.222889041651291641699117462849244475364685058593750000e+00; + a[4] = 4.447204118126878991112960193277103826403617858886718750e-01; + break; + + default: + AUBIO_ERROR ( "sampling rate of C-weighting filter is %d, should be one of\ + 8000, 16000, 22050, 44100, 96000, 192000.\n", samplerate ); + break; + + } + +} + +aubio_filter_t * new_aubio_filter_cdsgn (uint_t samplerate, uint_t channels) { + aubio_filter_t * f = new_aubio_filter(samplerate, 5, channels); + aubio_filter_set_cdsgn (f); return f; } diff --git a/src/temporal/cdesign.h b/src/temporal/cdesign.h index fc114461..49dfeceb 100644 --- a/src/temporal/cdesign.h +++ b/src/temporal/cdesign.h @@ -1,19 +1,20 @@ /* - Copyright (C) 2003-2007 Paul Brossier + Copyright (C) 2003-2009 Paul Brossier - This program 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 2 of the License, or - (at your option) any later version. + This file is part of aubio. - This program 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. + 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. - You should have received a copy of the GNU General Public License - along with this program; if not, write to the Free Software - Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + 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 . */ @@ -22,9 +23,30 @@ /** \file - Create a new C-design filter - - This file creates an IIR filter object with A-design coefficients. + Create a C-weighting filter + + This file creates a C-weighting digital filter, which reduces low and high + frequencies and enhance the middle ones to reflect the ability of the human + hearing. + + The implementation is based on the following standard: + + - IEC/CD 1672: Electroacoustics-Sound Level Meters, IEC, Geneva, Nov. 1996, + for A- and C-weighting filters. + + See also: + + - A-Weighting on + Wikipedia + - Weighting filter on + Wikipedia + - Christophe + Couvreur's 'octave' toolbox + + The coefficients in this file have been computed using Christophe Couvreur's + scripts in octave 3.0 (debian package 1:3.0.5-6+b2 with octave-signal + 1.0.9-1+b1 on i386), with 
 [b, a] = cdsign(1/Fs)
for various + sampling frequencies. */ @@ -34,16 +56,21 @@ extern "C" { /** create new C-design filter - \param samplerate sampling-rate of the signal to filter + \param samplerate sampling frequency of the signal to filter. Should be one of + 8000, 16000, 22050, 44100, 96000, 192000. \param channels number of channels to allocate + \return a new filter object + */ -aubio_filter_t * new_aubio_cdsgn_filter(uint_t samplerate, uint_t channels); +aubio_filter_t * new_aubio_filter_cdsgn (uint_t samplerate, uint_t channels); -/** filter input vector (in-place) */ -#define aubio_cdsgn_filter_do aubio_filter_do -/** delete c-design filter object */ -#define del_aubio_cdsgn_filter del_aubio_filter +/** set feedback and feedforward coefficients of a C-weighting filter + + \param f filter object to get coefficients from + +*/ +void aubio_filter_set_cdsgn (aubio_filter_t *f); #ifdef __cplusplus } diff --git a/src/temporal/filter.c b/src/temporal/filter.c index f3d0c91c..df4dba65 100644 --- a/src/temporal/filter.c +++ b/src/temporal/filter.c @@ -26,7 +26,15 @@ #include "lvec.h" #include "mathutils.h" #include "temporal/filter.h" -#include "temporal/filter_priv.h" + +struct _aubio_filter_t { + uint_t order; + uint_t samplerate; + lvec_t * a; + lvec_t * b; + lvec_t * y; + lvec_t * x; +}; void aubio_filter_do(aubio_filter_t * f, fvec_t * in) { aubio_filter_do_outplace(f, in, in); @@ -102,22 +110,41 @@ void aubio_filter_do_filtfilt(aubio_filter_t * f, fvec_t * in, fvec_t * tmp) { in->data[i][j] = tmp->data[i][length-j-1]; } -aubio_filter_t * new_aubio_filter(uint_t samplerate UNUSED, uint_t order, uint_t channels) { +lvec_t * aubio_filter_get_feedback ( aubio_filter_t *f ) { + return f->a; +} + +lvec_t * aubio_filter_get_feedforward ( aubio_filter_t *f ) { + return f->b; +} + +uint_t aubio_filter_get_order ( aubio_filter_t *f ) { + return f->order; +} + +uint_t aubio_filter_get_samplerate ( aubio_filter_t *f ) { + return f->samplerate; +} + +aubio_filter_t * new_aubio_filter(uint_t samplerate, + uint_t order, uint_t channels) { aubio_filter_t * f = AUBIO_NEW(aubio_filter_t); f->x = new_lvec(order, channels); f->y = new_lvec(order, channels); f->a = new_lvec(order, 1); f->b = new_lvec(order, 1); - f->a->data[0][1] = 1.; + f->samplerate = samplerate; f->order = order; + /* set default to identity */ + f->a->data[0][1] = 1.; return f; } void del_aubio_filter(aubio_filter_t * f) { - AUBIO_FREE(f->a); - AUBIO_FREE(f->b); - AUBIO_FREE(f->x); - AUBIO_FREE(f->y); + del_lvec(f->a); + del_lvec(f->b); + del_lvec(f->x); + del_lvec(f->y); AUBIO_FREE(f); return; } diff --git a/src/temporal/filter.h b/src/temporal/filter.h index c82e50db..0b86befe 100644 --- a/src/temporal/filter.h +++ b/src/temporal/filter.h @@ -22,56 +22,126 @@ /** \file - Infinite Impulse Response filter + Digital filter - This file implements IIR filters of any order: + This object stores a digital filter of order \f$n\f$ for \f$c\f$ channels. + It contains the following data: + - \f$ n*1 b_i \f$ feedforward coefficients + - \f$ n*1 a_i \f$ feedback coefficients + - \f$ n*c x_i \f$ input signal + - \f$ n*c y_i \f$ output signal + + For convenience, the samplerate of the input signal is also stored in the object. + + Feedforward and feedback parameters can be modified using + aubio_filter_get_feedback() and aubio_filter_get_feedforward(). + + The function aubio_filter_do_outplace() computes the following output signal + \f$ y[n] \f$ from the input signal \f$ x[n] \f$: - \f$ y[n] = b_1 x[n] + ... + b_{order} x[n-order] - - a_2 y[n-1] - ... - a_{order} y[n-order]\f$ + \f{eqnarray*}{ + y[n] = b_0 x[n] & + & b_1 x[n-1] + b_2 x[n-2] + ... + b_P x[n-P] \\ + & - & a_1 y[n-1] - a_2 y[n-2] - ... - a_P y[n-P] \\ + \f} - The filtfilt version runs the filter twice, forward and backward, to - compensate the phase shifting of the forward operation. + The function aubio_filter_do() executes the same computation but modifies + directly the input signal (in-place). + The function aubio_filter_do_filtfilt() version runs the filter twice, first + forward then backward, to compensate with the phase shifting of the forward + operation. + + Some convenience functions are provided: + - new_aubio_filter_adsgn() and aubio_filter_set_adsgn(), + - new_aubio_filter_cdsgn() and aubio_filter_set_cdsgn(). + */ #ifdef __cplusplus extern "C" { #endif -/** IIR filter object */ +/** Digital filter + +*/ typedef struct _aubio_filter_t aubio_filter_t; /** filter input vector (in-place) - \param b biquad object as returned by new_aubio_biquad + \param f filter object as returned by new_aubio_filter() \param in input vector to filter */ -void aubio_filter_do(aubio_filter_t * b, fvec_t * in); +void aubio_filter_do(aubio_filter_t * f, fvec_t * in); + /** filter input vector (out-of-place) - \param b biquad object as returned by new_aubio_biquad + \param f filter object as returned by new_aubio_filter() \param in input vector to filter \param out output vector to store filtered input */ -void aubio_filter_do_outplace(aubio_filter_t * b, fvec_t * in, fvec_t * out); +void aubio_filter_do_outplace(aubio_filter_t * f, fvec_t * in, fvec_t * out); + /** filter input vector forward and backward - \param b biquad object as returned by new_aubio_biquad - \param in input vector to filter + \param f ::aubio_filter_t object as returned by new_aubio_filter() + \param in ::fvec_t input vector to filter \param tmp memory space to use for computation */ -void aubio_filter_do_filtfilt(aubio_filter_t * b, fvec_t * in, fvec_t * tmp); -/** create new IIR filter +void aubio_filter_do_filtfilt(aubio_filter_t * f, fvec_t * in, fvec_t * tmp); + +/** returns a pointer to feedback coefficients \f$ a_i \f$ + + \param f filter object to get parameters from + + \return a pointer to the \f$ a_0 ... a_i ... a_P \f$ coefficients + +*/ +lvec_t * aubio_filter_get_feedback ( aubio_filter_t *f ); + +/** returns a pointer to feedforward coefficients \f$ b_i \f$ + + \param f filter object to get coefficients from + + \return a pointer to the \f$ b_0 ... b_i ... b_P \f$ coefficients + +*/ +lvec_t * aubio_filter_get_feedforward ( aubio_filter_t *f ); + +/** get order of the filter + + \param f filter to get order from + + \return the order of the filter + +*/ +uint_t aubio_filter_get_order ( aubio_filter_t *f ); + +/** get sampling rate of the filter + + \param f filter to get sampling rate from + + \return the sampling rate of the filter, in Hz + +*/ +uint_t aubio_filter_get_samplerate ( aubio_filter_t *f ); + +/** create new filter object + + This function creates a new ::aubio_filter_t object, given an order + and a specific number of channels. \param samplerate signal sampling rate \param order order of the filter (number of coefficients) \param channels number of channels to allocate + \return the newly created filter object + */ aubio_filter_t * new_aubio_filter(uint_t samplerate, uint_t order, uint_t channels); + /** delete a filter object \param f filter object to delete diff --git a/src/temporal/filter_priv.h b/src/temporal/filter_priv.h deleted file mode 100644 index e604c71e..00000000 --- a/src/temporal/filter_priv.h +++ /dev/null @@ -1,29 +0,0 @@ -/* - Copyright (C) 2003-2008 Paul Brossier - - This program 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 2 of the License, or - (at your option) any later version. - - This program 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 this program; if not, write to the Free Software - Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. - -*/ - -#include "lvec.h" -struct _aubio_filter_t { - uint_t order; - lvec_t * a; - lvec_t * b; - lvec_t * y; - lvec_t * x; -}; - - diff --git a/tests/src/temporal/test-aweighting.c b/tests/src/temporal/test-aweighting.c new file mode 100644 index 00000000..8694035d --- /dev/null +++ b/tests/src/temporal/test-aweighting.c @@ -0,0 +1,37 @@ +#include + +int main(){ + + aubio_filter_t * f; + + uint_t rates[] = { 8000, 16000, 22050, 44100, 96000, 192000}; + uint_t nrates = 6; + uint_t samplerate, i = 0; + uint_t channels = 2; + + for ( samplerate = rates[i]; i < nrates ; i++ ) { + f = new_aubio_filter_adsgn (samplerate, channels); + del_aubio_filter (f); + + f = new_aubio_filter (samplerate, 7, channels*2); + aubio_filter_set_adsgn (f); + del_aubio_filter (f); + } + + // samplerate unknown + f = new_aubio_filter_adsgn (12089, channels); + del_aubio_filter (f); + + // order to small + f = new_aubio_filter (samplerate, 2, channels*2); + aubio_filter_set_adsgn (f); + del_aubio_filter (f); + + // order to big + f = new_aubio_filter (samplerate, 12, channels*2); + aubio_filter_set_adsgn (f); + del_aubio_filter (f); + + return 0; +} + diff --git a/tests/src/temporal/test-cweighting.c b/tests/src/temporal/test-cweighting.c new file mode 100644 index 00000000..bcf952f8 --- /dev/null +++ b/tests/src/temporal/test-cweighting.c @@ -0,0 +1,37 @@ +#include + +int main(){ + + aubio_filter_t * f; + + uint_t rates[] = { 8000, 16000, 22050, 44100, 96000, 192000}; + uint_t nrates = 6; + uint_t samplerate, i = 0; + uint_t channels = 2; + + for ( samplerate = rates[i]; i < nrates ; i++ ) { + f = new_aubio_filter_cdsgn (samplerate, channels); + del_aubio_filter (f); + + f = new_aubio_filter (samplerate, 5, channels*2); + aubio_filter_set_cdsgn (f); + del_aubio_filter (f); + } + + // samplerate unknown + f = new_aubio_filter_cdsgn (12089, channels); + del_aubio_filter (f); + + // order to small + f = new_aubio_filter (samplerate, 2, channels*2); + aubio_filter_set_cdsgn (f); + del_aubio_filter (f); + + // order to big + f = new_aubio_filter (samplerate, 12, channels*2); + aubio_filter_set_cdsgn (f); + del_aubio_filter (f); + + return 0; +} + diff --git a/tests/src/test-filter.c b/tests/src/test-filter.c index 0bd800dc..45e67ca7 100644 --- a/tests/src/test-filter.c +++ b/tests/src/test-filter.c @@ -8,7 +8,7 @@ int main(){ fvec_t * out = new_fvec (win_s, channels); /* input buffer */ /* allocate fft and other memory space */ - aubio_filter_t * o = new_aubio_cdsgn_filter(44100, channels); + aubio_filter_t * o = new_aubio_filter_cdsgn (44100, channels); aubio_filter_do(o,in); aubio_filter_do_outplace(o,in,out);