| /* |
| * ReplayGainAnalysis - analyzes input samples and give the recommended dB change |
| * Copyright (C) 2001 David Robinson and Glen Sawyer |
| * Improvements and optimizations added by Frank Klemm, and by Marcel Muller |
| * |
| * 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 ( long samplefreq ); |
| * |
| * to initialize everything. Call |
| * |
| * AnalyzeSamples ( 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() |
| * |
| * will return the recommended dB level change for all samples analyzed |
| * SINCE THE LAST TIME you called GetTitleGain() OR InitGainAnalysis(). |
| * |
| * GetAlbumGain() |
| * |
| * 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; |
| * |
| * InitGainAnalysis ( 44100 ); |
| * for ( i = 1; i <= num_songs; i++ ) { |
| * while ( ( num_samples = getSongSamples ( song[i], left_samples, right_samples ) ) > 0 ) |
| * AnalyzeSamples ( left_samples, right_samples, num_samples, 2 ); |
| * fprintf ("Recommended dB change for song %2d: %+6.2f dB\n", i, GetTitleGain() ); |
| * } |
| * fprintf ("Recommended dB change for whole album: %+6.2f dB\n", GetAlbumGain() ); |
| */ |
| |
| /* |
| * 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 <filter order> number of previous samples |
| * AND up to <filter order> 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. |
| */ |
| |
| #ifdef HAVE_CONFIG_H |
| #include <config.h> |
| #endif |
| |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| |
| #include "lame.h" |
| #include "machine.h" |
| #include "gain_analysis.h" |
| |
| /* for each filter: */ |
| /* [0] 48 kHz, [1] 44.1 kHz, [2] 32 kHz, [3] 24 kHz, [4] 22050 Hz, [5] 16 kHz, [6] 12 kHz, [7] is 11025 Hz, [8] 8 kHz */ |
| |
| #ifdef WIN32 |
| #pragma warning ( disable : 4305 ) |
| #endif |
| |
| /*lint -save -e736 loss of precision */ |
| static const Float_t ABYule[9][2 * YULE_ORDER + 1] = { |
| {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[9][2 * BUTTER_ORDER + 1] = { |
| {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} |
| }; |
| |
| /*lint -restore */ |
| |
| #ifdef WIN32 |
| #pragma warning ( default : 4305 ) |
| #endif |
| |
| /* When calling this procedure, make sure that ip[-order] and op[-order] point to real data! */ |
| |
| static void |
| filterYule(const Float_t * input, Float_t * output, size_t nSamples, const Float_t * const kernel) |
| { |
| /*register double y; */ |
| |
| 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; |
| /* *output++ = (Float_t)y; */ |
| } |
| } |
| |
| static void |
| filterButter(const Float_t * input, Float_t * output, size_t nSamples, const Float_t * const kernel) |
| { /*register double y; */ |
| |
| 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; |
| /* *output++ = (Float_t)y; */ |
| } |
| } |
| |
| |
| /* returns a INIT_GAIN_ANALYSIS_OK if successful, INIT_GAIN_ANALYSIS_ERROR if not */ |
| |
| int |
| ResetSampleFrequency(replaygain_t * rgData, long samplefreq) |
| { |
| int i; |
| |
| /* zero out initial values */ |
| for (i = 0; i < MAX_ORDER; i++) |
| rgData->linprebuf[i] = rgData->lstepbuf[i] |
| = rgData->loutbuf[i] |
| = rgData->rinprebuf[i] |
| = rgData->rstepbuf[i] |
| = rgData->routbuf[i] = 0.; |
| |
| switch ((int) (samplefreq)) { |
| case 48000: |
| rgData->freqindex = 0; |
| break; |
| case 44100: |
| rgData->freqindex = 1; |
| break; |
| case 32000: |
| rgData->freqindex = 2; |
| break; |
| case 24000: |
| rgData->freqindex = 3; |
| break; |
| case 22050: |
| rgData->freqindex = 4; |
| break; |
| case 16000: |
| rgData->freqindex = 5; |
| break; |
| case 12000: |
| rgData->freqindex = 6; |
| break; |
| case 11025: |
| rgData->freqindex = 7; |
| break; |
| case 8000: |
| rgData->freqindex = 8; |
| break; |
| default: |
| return INIT_GAIN_ANALYSIS_ERROR; |
| } |
| |
| rgData->sampleWindow = |
| (samplefreq * RMS_WINDOW_TIME_NUMERATOR + RMS_WINDOW_TIME_DENOMINATOR - |
| 1) / RMS_WINDOW_TIME_DENOMINATOR; |
| |
| rgData->lsum = 0.; |
| rgData->rsum = 0.; |
| rgData->totsamp = 0; |
| |
| memset(rgData->A, 0, sizeof(rgData->A)); |
| |
| return INIT_GAIN_ANALYSIS_OK; |
| } |
| |
| int |
| InitGainAnalysis(replaygain_t * rgData, long samplefreq) |
| { |
| if (ResetSampleFrequency(rgData, samplefreq) != INIT_GAIN_ANALYSIS_OK) { |
| return INIT_GAIN_ANALYSIS_ERROR; |
| } |
| |
| rgData->linpre = rgData->linprebuf + MAX_ORDER; |
| rgData->rinpre = rgData->rinprebuf + MAX_ORDER; |
| rgData->lstep = rgData->lstepbuf + MAX_ORDER; |
| rgData->rstep = rgData->rstepbuf + MAX_ORDER; |
| rgData->lout = rgData->loutbuf + MAX_ORDER; |
| rgData->rout = rgData->routbuf + MAX_ORDER; |
| |
| memset(rgData->B, 0, sizeof(rgData->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(replaygain_t * rgData, 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; |
| break; |
| case 2: |
| break; |
| default: |
| return GAIN_ANALYSIS_ERROR; |
| } |
| |
| if (num_samples < MAX_ORDER) { |
| memcpy(rgData->linprebuf + MAX_ORDER, left_samples, num_samples * sizeof(Float_t)); |
| memcpy(rgData->rinprebuf + MAX_ORDER, right_samples, num_samples * sizeof(Float_t)); |
| } |
| else { |
| memcpy(rgData->linprebuf + MAX_ORDER, left_samples, MAX_ORDER * sizeof(Float_t)); |
| memcpy(rgData->rinprebuf + MAX_ORDER, right_samples, MAX_ORDER * sizeof(Float_t)); |
| } |
| |
| while (batchsamples > 0) { |
| cursamples = batchsamples > rgData->sampleWindow - rgData->totsamp ? |
| rgData->sampleWindow - rgData->totsamp : batchsamples; |
| if (cursamplepos < MAX_ORDER) { |
| curleft = rgData->linpre + cursamplepos; |
| curright = rgData->rinpre + cursamplepos; |
| if (cursamples > MAX_ORDER - cursamplepos) |
| cursamples = MAX_ORDER - cursamplepos; |
| } |
| else { |
| curleft = left_samples + cursamplepos; |
| curright = right_samples + cursamplepos; |
| } |
| |
| YULE_FILTER(curleft, rgData->lstep + rgData->totsamp, cursamples, |
| ABYule[rgData->freqindex]); |
| YULE_FILTER(curright, rgData->rstep + rgData->totsamp, cursamples, |
| ABYule[rgData->freqindex]); |
| |
| BUTTER_FILTER(rgData->lstep + rgData->totsamp, rgData->lout + rgData->totsamp, cursamples, |
| ABButter[rgData->freqindex]); |
| BUTTER_FILTER(rgData->rstep + rgData->totsamp, rgData->rout + rgData->totsamp, cursamples, |
| ABButter[rgData->freqindex]); |
| |
| curleft = rgData->lout + rgData->totsamp; /* Get the squared values */ |
| curright = rgData->rout + rgData->totsamp; |
| |
| i = cursamples % 8; |
| while (i--) { |
| rgData->lsum += fsqr(*curleft++); |
| rgData->rsum += fsqr(*curright++); |
| } |
| i = cursamples / 8; |
| while (i--) { |
| rgData->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]); |
| curleft += 8; |
| rgData->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]); |
| curright += 8; |
| } |
| |
| batchsamples -= cursamples; |
| cursamplepos += cursamples; |
| rgData->totsamp += cursamples; |
| if (rgData->totsamp == rgData->sampleWindow) { /* Get the Root Mean Square (RMS) for this set of samples */ |
| double const val = |
| STEPS_per_dB * 10. * log10((rgData->lsum + rgData->rsum) / rgData->totsamp * 0.5 + |
| 1.e-37); |
| size_t ival = (val <= 0) ? 0 : (size_t) val; |
| if (ival >= sizeof(rgData->A) / sizeof(*(rgData->A))) |
| ival = sizeof(rgData->A) / sizeof(*(rgData->A)) - 1; |
| rgData->A[ival]++; |
| rgData->lsum = rgData->rsum = 0.; |
| memmove(rgData->loutbuf, rgData->loutbuf + rgData->totsamp, |
| MAX_ORDER * sizeof(Float_t)); |
| memmove(rgData->routbuf, rgData->routbuf + rgData->totsamp, |
| MAX_ORDER * sizeof(Float_t)); |
| memmove(rgData->lstepbuf, rgData->lstepbuf + rgData->totsamp, |
| MAX_ORDER * sizeof(Float_t)); |
| memmove(rgData->rstepbuf, rgData->rstepbuf + rgData->totsamp, |
| MAX_ORDER * sizeof(Float_t)); |
| rgData->totsamp = 0; |
| } |
| if (rgData->totsamp > rgData->sampleWindow) /* somehow I really screwed up: Error in programming! Contact author about totsamp > sampleWindow */ |
| return GAIN_ANALYSIS_ERROR; |
| } |
| if (num_samples < MAX_ORDER) { |
| memmove(rgData->linprebuf, rgData->linprebuf + num_samples, |
| (MAX_ORDER - num_samples) * sizeof(Float_t)); |
| memmove(rgData->rinprebuf, rgData->rinprebuf + num_samples, |
| (MAX_ORDER - num_samples) * sizeof(Float_t)); |
| memcpy(rgData->linprebuf + MAX_ORDER - num_samples, left_samples, |
| num_samples * sizeof(Float_t)); |
| memcpy(rgData->rinprebuf + MAX_ORDER - num_samples, right_samples, |
| num_samples * sizeof(Float_t)); |
| } |
| else { |
| memcpy(rgData->linprebuf, left_samples + num_samples - MAX_ORDER, |
| MAX_ORDER * sizeof(Float_t)); |
| memcpy(rgData->rinprebuf, right_samples + num_samples - MAX_ORDER, |
| MAX_ORDER * sizeof(Float_t)); |
| } |
| |
| return GAIN_ANALYSIS_OK; |
| } |
| |
| |
| static Float_t |
| analyzeResult(uint32_t const *Array, size_t len) |
| { |
| uint32_t elems; |
| 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(replaygain_t * rgData) |
| { |
| Float_t retval; |
| unsigned int i; |
| |
| retval = analyzeResult(rgData->A, sizeof(rgData->A) / sizeof(*(rgData->A))); |
| |
| for (i = 0; i < sizeof(rgData->A) / sizeof(*(rgData->A)); i++) { |
| rgData->B[i] += rgData->A[i]; |
| rgData->A[i] = 0; |
| } |
| |
| for (i = 0; i < MAX_ORDER; i++) |
| rgData->linprebuf[i] = rgData->lstepbuf[i] |
| = rgData->loutbuf[i] |
| = rgData->rinprebuf[i] |
| = rgData->rstepbuf[i] |
| = rgData->routbuf[i] = 0.f; |
| |
| rgData->totsamp = 0; |
| rgData->lsum = rgData->rsum = 0.; |
| return retval; |
| } |
| |
| |
| Float_t |
| GetAlbumGain(replaygain_t * rgData) |
| { |
| return analyzeResult(rgData->B, sizeof(rgData->B) / sizeof(*(rgData->B))); |
| } |
| |
| /* end of gain_analysis.c */ |
