/* * ReplayGainAnalysis - analyzes input samples and give the recommended dB change * Copyright (C) 2001-2009 David Robinson and Glen Sawyer * Improvements and optimizations added by Frank Klemm, and by Marcel Müller * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * * concept and filter values by David Robinson (David@Robinson.org) * -- blame him if you think the idea is flawed * original coding by Glen Sawyer (mp3gain@hotmail.com) * -- blame him if you think this runs too slowly, or the coding is otherwise flawed * * lots of code improvements by Frank Klemm ( http://www.uni-jena.de/~pfk/mpp/ ) * -- credit him for all the _good_ programming ;) * * * For an explanation of the concepts and the basic algorithms involved, go to: * http://www.replaygain.org/ */ /* * Here's the deal. Call * * InitGainAnalysis (GainHandle_t **handle, long samplefreq ); * * to initialize everything. Call * * AnalyzeSamples ( GainHandle_t* handle, * const Float_t* left_samples, * const Float_t* right_samples, * size_t num_samples, * int num_channels ); * * as many times as you want, with as many or as few samples as you want. * If mono, pass the sample buffer in through left_samples, leave * right_samples NULL, and make sure num_channels = 1. * * GetTitleGain(GainHandle_t *handle) * * will return the recommended dB level change for all samples analyzed * SINCE THE LAST TIME you called GetTitleGain() OR InitGainAnalysis(). * * GetAlbumGain(GainHandle_t **handle, int count) * * will return the recommended dB level change for all samples analyzed * since InitGainAnalysis() was called and finalized with GetTitleGain(). * * Pseudo-code to process an album: * * Float_t l_samples [4096]; * Float_t r_samples [4096]; * size_t num_samples; * unsigned int num_songs; * unsigned int i; * GainHandle_t **a = (GainHandle_t **) malloc(num_songs*sizeof(GainHandle_t *)); * * * for (i = 0; i < num_songs; i++) * { * GainHandle_t *handle; * InitGainAnalysis (&handle, 44100); * while((num_samples = getSongSamples(song[i], left_samples, right_samples)) > 0) * { * AnalyzeSamples (handle, left_samples, right_samples, num_samples, 2); * } * a[i] = handle; * fprintf("Recommended dB change for song %2d: %+6.2f dB\n", i+1, GetTitleGain(handle)); * } * fprintf ("Recommended dB change for whole album: %+6.2f dB\n", GetAlbumGain(a, num_songs)); * for (i = 0; i < num_songs; i++) * DeinitGainAbalysis(a[i]); */ /* * So here's the main source of potential code confusion: * * The filters applied to the incoming samples are IIR filters, * meaning they rely on up to number of previous samples * AND up to number of previous filtered samples. * * I set up the AnalyzeSamples routine to minimize memory usage and interface * complexity. The speed isn't compromised too much (I don't think), but the * internal complexity is higher than it should be for such a relatively * simple routine. * * Optimization/clarity suggestions are welcome. */ /* modifications compared to original code: added full reentrancy support fixed gcc warnings */ #include #include #include #include #include "gain_analysis.h" typedef unsigned short Uint16_t; typedef signed short Int16_t; typedef unsigned int Uint32_t; typedef signed int Int32_t; #define YULE_ORDER 10 #define BUTTER_ORDER 2 #define YULE_FILTER filterYule #define BUTTER_FILTER filterButter #define RMS_PERCENTILE 0.95 // percentile which is louder than the proposed level #define MAX_SAMP_FREQ 96000 // maximum allowed sample frequency [Hz] #define RMS_WINDOW_TIME 50 // Time slice size [ms] #define STEPS_per_dB 100 // Table entries per dB #define MAX_dB 120 // Table entries for 0...MAX_dB (normal max. values are 70...80 dB) #define MAX_ORDER (BUTTER_ORDER > YULE_ORDER ? BUTTER_ORDER : YULE_ORDER) #define MAX_SAMPLES_PER_WINDOW (size_t) (MAX_SAMP_FREQ * RMS_WINDOW_TIME / 1000 + 1) // max. Samples per Time slice #define PINK_REF 64.82 //298640883795 // calibration value struct GainHandle { Float_t linprebuf [MAX_ORDER * 2]; Float_t* linpre; // left input samples, with pre-buffer Float_t lstepbuf [MAX_SAMPLES_PER_WINDOW + MAX_ORDER]; Float_t* lstep; // left "first step" (i.e. post first filter) samples Float_t loutbuf [MAX_SAMPLES_PER_WINDOW + MAX_ORDER]; Float_t* lout; // left "out" (i.e. post second filter) samples Float_t rinprebuf [MAX_ORDER * 2]; Float_t* rinpre; // right input samples ... Float_t rstepbuf [MAX_SAMPLES_PER_WINDOW + MAX_ORDER]; Float_t* rstep; Float_t routbuf [MAX_SAMPLES_PER_WINDOW + MAX_ORDER]; Float_t* rout; long sampleWindow; // number of samples required to reach number of milliseconds required for RMS window long totsamp; double lsum; double rsum; int freqindex; int first; Uint32_t A [(size_t)(STEPS_per_dB * MAX_dB)]; }; // for each filter: // [0] 96 kHz, [1] 88.2, [2] 64 kHz, [3] 48 kHz, [4] 44.1 kHz, [5] 32 kHz, // [6] 24 kHz, [7] 22050 Hz, [8] 16 kHz, [9] 12 kHz, [10] is 11025 Hz, [11] 8 kHz #ifdef WIN32 #ifndef __GNUC__ #pragma warning ( disable : 4305 ) #endif #endif static const Float_t ABYule[12][2*YULE_ORDER + 1] = { {0.006471345933032, -7.22103125152679, -0.02567678242161, 24.7034187975904, 0.049805860704367, -52.6825833623896, -0.05823001743528, 77.4825736677539, 0.040611847441914, -82.0074753444205, -0.010912036887501, 63.1566097101925, -0.00901635868667, -34.889569769245, 0.012448886238123, 13.2126852760198, -0.007206683749426, -3.09445623301669, 0.002167156433951, 0.340344741393305, -0.000261819276949}, {0.015415414474287, -7.19001570087017, -0.07691359399407, 24.4109412087159, 0.196677418516518, -51.6306373580801, -0.338855114128061, 75.3978476863163, 0.430094579594561, -79.4164552507386, -0.415015413747894, 61.0373661948115, 0.304942508151101, -33.7446462547014, -0.166191795926663, 12.8168791146274, 0.063198189938739, -3.01332198541437, -0.015003978694525, 0.223619893831468, 0.001748085184539}, {0.021776466467053, -5.74819833657784, -0.062376961003801, 16.246507961894, 0.107731165328514, -29.9691822642542, -0.150994515142316, 40.027597579378, 0.170334807313632, -40.3209196052655, -0.157984942890531, 30.8542077487718, 0.121639833268721, -17.5965138737281, -0.074094040816409, 7.10690214103873, 0.031282852041061, -1.82175564515191, -0.00755421235941, 0.223619893831468, 0.00117925454213 }, {0.03857599435200, -3.84664617118067, -0.02160367184185, 7.81501653005538, -0.00123395316851, -11.34170355132042, -0.00009291677959, 13.05504219327545, -0.01655260341619, -12.28759895145294, 0.02161526843274, 9.48293806319790, -0.02074045215285, -5.87257861775999, 0.00594298065125, 2.75465861874613, 0.00306428023191, -0.86984376593551, 0.00012025322027, 0.13919314567432, 0.00288463683916 }, {0.05418656406430, -3.47845948550071, -0.02911007808948, 6.36317777566148, -0.00848709379851, -8.54751527471874, -0.00851165645469, 9.47693607801280, -0.00834990904936, -8.81498681370155, 0.02245293253339, 6.85401540936998, -0.02596338512915, -4.39470996079559, 0.01624864962975, 2.19611684890774, -0.00240879051584, -0.75104302451432, 0.00674613682247, 0.13149317958808, -0.00187763777362 }, {0.15457299681924, -2.37898834973084, -0.09331049056315, 2.84868151156327, -0.06247880153653, -2.64577170229825, 0.02163541888798, 2.23697657451713, -0.05588393329856, -1.67148153367602, 0.04781476674921, 1.00595954808547, 0.00222312597743, -0.45953458054983, 0.03174092540049, 0.16378164858596, -0.01390589421898, -0.05032077717131, 0.00651420667831, 0.02347897407020, -0.00881362733839 }, {0.30296907319327, -1.61273165137247, -0.22613988682123, 1.07977492259970, -0.08587323730772, -0.25656257754070, 0.03282930172664, -0.16276719120440, -0.00915702933434, -0.22638893773906, -0.02364141202522, 0.39120800788284, -0.00584456039913, -0.22138138954925, 0.06276101321749, 0.04500235387352, -0.00000828086748, 0.02005851806501, 0.00205861885564, 0.00302439095741, -0.02950134983287 }, {0.33642304856132, -1.49858979367799, -0.25572241425570, 0.87350271418188, -0.11828570177555, 0.12205022308084, 0.11921148675203, -0.80774944671438, -0.07834489609479, 0.47854794562326, -0.00469977914380, -0.12453458140019, -0.00589500224440, -0.04067510197014, 0.05724228140351, 0.08333755284107, 0.00832043980773, -0.04237348025746, -0.01635381384540, 0.02977207319925, -0.01760176568150 }, {0.44915256608450, -0.62820619233671, -0.14351757464547, 0.29661783706366, -0.22784394429749, -0.37256372942400, -0.01419140100551, 0.00213767857124, 0.04078262797139, -0.42029820170918, -0.12398163381748, 0.22199650564824, 0.04097565135648, 0.00613424350682, 0.10478503600251, 0.06747620744683, -0.01863887810927, 0.05784820375801, -0.03193428438915, 0.03222754072173, 0.00541907748707 }, {0.56619470757641, -1.04800335126349, -0.75464456939302, 0.29156311971249, 0.16242137742230, -0.26806001042947, 0.16744243493672, 0.00819999645858, -0.18901604199609, 0.45054734505008, 0.30931782841830, -0.33032403314006, -0.27562961986224, 0.06739368333110, 0.00647310677246, -0.04784254229033, 0.08647503780351, 0.01639907836189, -0.03788984554840, 0.01807364323573, -0.00588215443421 }, {0.58100494960553, -0.51035327095184, -0.53174909058578, -0.31863563325245, -0.14289799034253, -0.20256413484477, 0.17520704835522, 0.14728154134330, 0.02377945217615, 0.38952639978999, 0.15558449135573, -0.23313271880868, -0.25344790059353, -0.05246019024463, 0.01628462406333, -0.02505961724053, 0.06920467763959, 0.02442357316099, -0.03721611395801, 0.01818801111503, -0.00749618797172 }, {0.53648789255105, -0.25049871956020, -0.42163034350696, -0.43193942311114, -0.00275953611929, -0.03424681017675, 0.04267842219415, -0.04678328784242, -0.10214864179676, 0.26408300200955, 0.14590772289388, 0.15113130533216, -0.02459864859345, -0.17556493366449, -0.11202315195388, -0.18823009262115, -0.04060034127000, 0.05477720428674, 0.04788665548180, 0.04704409688120, -0.02217936801134 } }; static const Float_t ABButter[12][2*BUTTER_ORDER + 1] = { {0.99308203517541, -1.98611621154089, -1.98616407035082, 0.986211929160751, 0.99308203517541 }, {0.992472550461293,-1.98488843762334, -1.98494510092258, 0.979389350028798, 0.992472550461293}, {0.989641019334721,-1.97917472731008, -1.97928203866944, 0.979389350028798, 0.989641019334721}, {0.98621192462708, -1.97223372919527, -1.97242384925416, 0.97261396931306, 0.98621192462708 }, {0.98500175787242, -1.96977855582618, -1.97000351574484, 0.97022847566350, 0.98500175787242 }, {0.97938932735214, -1.95835380975398, -1.95877865470428, 0.95920349965459, 0.97938932735214 }, {0.97531843204928, -1.95002759149878, -1.95063686409857, 0.95124613669835, 0.97531843204928 }, {0.97316523498161, -1.94561023566527, -1.94633046996323, 0.94705070426118, 0.97316523498161 }, {0.96454515552826, -1.92783286977036, -1.92909031105652, 0.93034775234268, 0.96454515552826 }, {0.96009142950541, -1.91858953033784, -1.92018285901082, 0.92177618768381, 0.96009142950541 }, {0.95856916599601, -1.91542108074780, -1.91713833199203, 0.91885558323625, 0.95856916599601 }, {0.94597685600279, -1.88903307939452, -1.89195371200558, 0.89487434461664, 0.94597685600279 } }; #ifdef WIN32 #ifndef __GNUC__ #pragma warning ( default : 4305 ) #endif #endif // When calling these filter procedures, make sure that ip[-order] and op[-order] point to real data! // If your compiler complains that "'operation on 'output' may be undefined", you can // either ignore the warnings or uncomment the three "y" lines (and comment out the indicated line) static void filterYule (const Float_t* input, Float_t* output, size_t nSamples, const Float_t* kernel) { while (nSamples--) { *output = 1e-10 /* 1e-10 is a hack to avoid slowdown because of denormals */ + input [0] * kernel[0] - output[-1] * kernel[1] + input [-1] * kernel[2] - output[-2] * kernel[3] + input [-2] * kernel[4] - output[-3] * kernel[5] + input [-3] * kernel[6] - output[-4] * kernel[7] + input [-4] * kernel[8] - output[-5] * kernel[9] + input [-5] * kernel[10] - output[-6] * kernel[11] + input [-6] * kernel[12] - output[-7] * kernel[13] + input [-7] * kernel[14] - output[-8] * kernel[15] + input [-8] * kernel[16] - output[-9] * kernel[17] + input [-9] * kernel[18] - output[-10]* kernel[19] + input [-10]* kernel[20]; ++output; ++input; } } static void filterButter (const Float_t* input, Float_t* output, size_t nSamples, const Float_t* kernel) { while (nSamples--) { *output = input [0] * kernel[0] - output[-1] * kernel[1] + input [-1] * kernel[2] - output[-2] * kernel[3] + input [-2] * kernel[4]; ++output; ++input; } } // returns a INIT_GAIN_ANALYSIS_OK if successful, INIT_GAIN_ANALYSIS_ERROR if not int ResetSampleFrequency (GainHandle_t *handle, long samplefreq) { int i = 0; // zero out initial values for (i = 0; i < MAX_ORDER; i++) { handle->linprebuf[i] = handle->lstepbuf[i] = handle->loutbuf[i] = 0; handle->rinprebuf[i] = handle->rstepbuf[i] = handle->routbuf[i] = 0.; } switch ((int)(samplefreq)) { case 96000: handle->freqindex = 0; break; case 88200: handle->freqindex = 1; break; case 64000: handle->freqindex = 2; break; case 48000: handle->freqindex = 3; break; case 44100: handle->freqindex = 4; break; case 32000: handle->freqindex = 5; break; case 24000: handle->freqindex = 6; break; case 22050: handle->freqindex = 7; break; case 16000: handle->freqindex = 8; break; case 12000: handle->freqindex = 9; break; case 11025: handle->freqindex = 10; break; case 8000: handle->freqindex = 11; break; default: return INIT_GAIN_ANALYSIS_ERROR; } handle->sampleWindow = (int) ceil (samplefreq * RMS_WINDOW_TIME / 1000); handle->lsum = 0.; handle->rsum = 0.; handle->totsamp = 0; memset (handle->A, 0, sizeof(handle->A)); return INIT_GAIN_ANALYSIS_OK; } int InitGainAnalysis (GainHandle_t **handle, long samplefreq ) { *handle = malloc(sizeof(GainHandle_t)); if (ResetSampleFrequency(*handle, samplefreq) != INIT_GAIN_ANALYSIS_OK) { return INIT_GAIN_ANALYSIS_ERROR; } (*handle)->linpre = (*handle)->linprebuf + MAX_ORDER; (*handle)->rinpre = (*handle)->rinprebuf + MAX_ORDER; (*handle)->lstep = (*handle)->lstepbuf + MAX_ORDER; (*handle)->rstep = (*handle)->rstepbuf + MAX_ORDER; (*handle)->lout = (*handle)->loutbuf + MAX_ORDER; (*handle)->rout = (*handle)->routbuf + MAX_ORDER; //memset((*handle)->B, 0, sizeof((*handle)->B)); return INIT_GAIN_ANALYSIS_OK; } // returns GAIN_ANALYSIS_OK if successful, GAIN_ANALYSIS_ERROR if not static __inline double fsqr(const double d) { return d*d; } int AnalyzeSamples (GainHandle_t *handle, const Float_t* left_samples, const Float_t* right_samples, size_t num_samples, int num_channels) { const Float_t* curleft; const Float_t* curright; long batchsamples; long cursamples; long cursamplepos; int i; if ( num_samples == 0 ) return GAIN_ANALYSIS_OK; cursamplepos = 0; batchsamples = (long)num_samples; switch ( num_channels) { case 1: right_samples = left_samples; case 2: break; default: return GAIN_ANALYSIS_ERROR; } if (num_samples < MAX_ORDER) { memcpy (handle->linprebuf + MAX_ORDER, left_samples , num_samples * sizeof(Float_t) ); memcpy (handle->rinprebuf + MAX_ORDER, right_samples, num_samples * sizeof(Float_t) ); } else { memcpy (handle->linprebuf + MAX_ORDER, left_samples, MAX_ORDER * sizeof(Float_t) ); memcpy (handle->rinprebuf + MAX_ORDER, right_samples, MAX_ORDER * sizeof(Float_t) ); } while (batchsamples > 0) { cursamples = batchsamples > handle->sampleWindow - handle->totsamp ? handle->sampleWindow - handle->totsamp : batchsamples; if (cursamplepos < MAX_ORDER) { curleft = handle->linpre + cursamplepos; curright = handle->rinpre + cursamplepos; if (cursamples > MAX_ORDER - cursamplepos) cursamples = MAX_ORDER - cursamplepos; } else { curleft = left_samples + cursamplepos; curright = right_samples + cursamplepos; } YULE_FILTER (curleft, handle->lstep + handle->totsamp, cursamples, ABYule[handle->freqindex]); YULE_FILTER (curright, handle->rstep + handle->totsamp, cursamples, ABYule[handle->freqindex]); BUTTER_FILTER (handle->lstep + handle->totsamp, handle->lout + handle->totsamp, cursamples, ABButter[handle->freqindex]); BUTTER_FILTER (handle->rstep + handle->totsamp, handle->rout + handle->totsamp, cursamples, ABButter[handle->freqindex]); curleft = handle->lout + handle->totsamp; // Get the squared values curright = handle->rout + handle->totsamp; i = cursamples % 16; while (i--) { handle->lsum += fsqr(*curleft++); handle->rsum += fsqr(*curright++); } i = cursamples / 16; while (i--) { handle->lsum += fsqr(curleft[0]) + fsqr(curleft[1]) + fsqr(curleft[2]) + fsqr(curleft[3]) + fsqr(curleft[4]) + fsqr(curleft[5]) + fsqr(curleft[6]) + fsqr(curleft[7]) + fsqr(curleft[8]) + fsqr(curleft[9]) + fsqr(curleft[10]) + fsqr(curleft[11]) + fsqr(curleft[12]) + fsqr(curleft[13]) + fsqr(curleft[14]) + fsqr(curleft[15]); curleft += 16; handle->rsum += fsqr(curright[0]) + fsqr(curright[1]) + fsqr(curright[2]) + fsqr(curright[3]) + fsqr(curright[4]) + fsqr(curright[5]) + fsqr(curright[6]) + fsqr(curright[7]) + fsqr(curright[8]) + fsqr(curright[9]) + fsqr(curright[10]) + fsqr(curright[11]) + fsqr(curright[12]) + fsqr(curright[13]) + fsqr(curright[14]) + fsqr(curright[15]); curright += 16; } batchsamples -= cursamples; cursamplepos += cursamples; handle->totsamp += cursamples; if (handle->totsamp == handle->sampleWindow) { // Get the Root Mean Square (RMS) for this set of samples double val = STEPS_per_dB * 10. * log10((handle->lsum+handle->rsum) / handle->totsamp * 0.5 + 1.e-37); int ival = (int) val; if ( ival < 0 ) ival = 0; if ( ival >= (int)(sizeof(handle->A)/sizeof(*handle->A)) ) ival = sizeof(handle->A)/sizeof(*handle->A) - 1; handle->A [ival]++; handle->lsum = handle->rsum = 0.; memmove (handle->loutbuf , handle->loutbuf + handle->totsamp, MAX_ORDER * sizeof(Float_t) ); memmove (handle->routbuf , handle->routbuf + handle->totsamp, MAX_ORDER * sizeof(Float_t) ); memmove (handle->lstepbuf, handle->lstepbuf + handle->totsamp, MAX_ORDER * sizeof(Float_t) ); memmove (handle->rstepbuf, handle->rstepbuf + handle->totsamp, MAX_ORDER * sizeof(Float_t) ); handle->totsamp = 0; } if (handle->totsamp > handle->sampleWindow) // somehow I really screwed up: Error in programming! Contact author about totsamp > sampleWindow return GAIN_ANALYSIS_ERROR; } if (num_samples < MAX_ORDER) { memmove(handle->linprebuf, handle->linprebuf + num_samples, (MAX_ORDER-num_samples) * sizeof(Float_t) ); memmove(handle->rinprebuf, handle->rinprebuf + num_samples, (MAX_ORDER-num_samples) * sizeof(Float_t) ); memcpy(handle->linprebuf + MAX_ORDER - num_samples, left_samples, num_samples * sizeof(Float_t)); memcpy(handle->rinprebuf + MAX_ORDER - num_samples, right_samples, num_samples * sizeof(Float_t)); } else { memcpy(handle->linprebuf, left_samples + num_samples - MAX_ORDER, MAX_ORDER * sizeof(Float_t)); memcpy(handle->rinprebuf, right_samples + num_samples - MAX_ORDER, MAX_ORDER * sizeof(Float_t)); } return GAIN_ANALYSIS_OK; } static Float_t analyzeResult (Uint32_t* Array, size_t len) { Uint32_t elems = 0; Int32_t upper; size_t i; elems = 0; for (i = 0; i < len; i++) elems += Array[i]; if (elems == 0) return GAIN_NOT_ENOUGH_SAMPLES; upper = (Int32_t) ceil (elems * (1. - RMS_PERCENTILE)); for (i = len; i-- > 0; ) { if ((upper -= Array[i]) <= 0) break; } return (Float_t) ((Float_t)PINK_REF - (Float_t)i / (Float_t)STEPS_per_dB); } Float_t GetTitleGain(GainHandle_t *handle) { Float_t retval; int i = 0; retval = analyzeResult (handle->A, sizeof(handle->A)/sizeof(*handle->A)); /*for (i = 0; i < (int)(sizeof(handle->A)/sizeof(*handle->A)); i++ ) { handle->B[i] += handle->A[i]; handle->A[i] = 0; }*/ for (i = 0; i < MAX_ORDER; i++ ) { handle->linprebuf[i] = handle->lstepbuf[i] = handle->loutbuf[i] = 0.f; handle->rinprebuf[i] = handle->rstepbuf[i] = handle->routbuf[i] = 0.f; } handle->totsamp = 0; handle->lsum = handle->rsum = 0.; return retval; } Float_t GetAlbumGain(GainHandle_t **handle, int count) { Uint32_t B [(size_t)(STEPS_per_dB * MAX_dB)]; memset (B, 0, sizeof(B)); int i = 0; unsigned int j = 0; for(i = 0; i < count; ++i) { for(j = 0; j < sizeof(handle[i]->A)/sizeof(*handle[i]->A); ++j) { B[j] += handle[i]->A[j]; } } return analyzeResult(B, sizeof(B)/sizeof(*B)); } void DeinitGainAbalysis(GainHandle_t *handle) { free(handle); } /* end of gain_analysis.c */