/* replaygain_synthesis - Routines for applying ReplayGain to a signal * Copyright (C) 2002,2003,2004 Josh Coalson * * 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /* * This is an aggregation of pieces of code from John Edwards' WaveGain * program. Mostly cosmetic changes were made; otherwise, the dithering * code is almost untouched and the gain processing was converted from * processing a whole file to processing chunks of samples. * * The original copyright notices for WaveGain's dither.c and wavegain.c * appear below: */ /* * (c) 2002 John Edwards * mostly lifted from work by Frank Klemm * random functions for dithering. */ /* * Copyright (C) 2002 John Edwards * Additional code by Magnus Holmgren and Gian-Carlo Pascutto */ #include /* for memset() */ #include #include "private/fast_float_math_hack.h" #include "replaygain_synthesis.h" #include "FLAC/assert.h" #if defined _MSC_VER #define FLAC__INLINE __inline #else #define FLAC__INLINE #endif /* adjust for compilers that can't understand using LLU suffix for uint64_t literals */ #ifdef _MSC_VER #define FLAC__I64L(x) x #else #define FLAC__I64L(x) x##LL #endif /* * the following is based on parts of dither.c */ /* * This is a simple random number generator with good quality for audio purposes. * It consists of two polycounters with opposite rotation direction and different * periods. The periods are coprime, so the total period is the product of both. * * ------------------------------------------------------------------------------------------------- * +-> |31:30:29:28:27:26:25:24:23:22:21:20:19:18:17:16:15:14:13:12:11:10: 9: 8: 7: 6: 5: 4: 3: 2: 1: 0| * | ------------------------------------------------------------------------------------------------- * | | | | | | | * | +--+--+--+-XOR-+--------+ * | | * +--------------------------------------------------------------------------------------+ * * ------------------------------------------------------------------------------------------------- * |31:30:29:28:27:26:25:24:23:22:21:20:19:18:17:16:15:14:13:12:11:10: 9: 8: 7: 6: 5: 4: 3: 2: 1: 0| <-+ * ------------------------------------------------------------------------------------------------- | * | | | | | * +--+----XOR----+--+ | * | | * +----------------------------------------------------------------------------------------+ * * * The first has an period of 3*5*17*257*65537, the second of 7*47*73*178481, * which gives a period of 18.410.713.077.675.721.215. The result is the * XORed values of both generators. */ static unsigned int random_int_() { static const unsigned char parity_[256] = { 0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1, 1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0, 1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0, 0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1, 1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0, 0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1, 0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1, 1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0 }; static unsigned int r1_ = 1; static unsigned int r2_ = 1; unsigned int t1, t2, t3, t4; /* Parity calculation is done via table lookup, this is also available * on CPUs without parity, can be implemented in C and avoid unpredictable * jumps and slow rotate through the carry flag operations. */ t3 = t1 = r1_; t4 = t2 = r2_; t1 &= 0xF5; t2 >>= 25; t1 = parity_[t1]; t2 &= 0x63; t1 <<= 31; t2 = parity_[t2]; return (r1_ = (t3 >> 1) | t1 ) ^ (r2_ = (t4 + t4) | t2 ); } /* gives a equal distributed random number */ /* between -2^31*mult and +2^31*mult */ static double random_equi_(double mult) { return mult * (int) random_int_(); } /* gives a triangular distributed random number */ /* between -2^32*mult and +2^32*mult */ static double random_triangular_(double mult) { return mult * ( (double) (int) random_int_() + (double) (int) random_int_() ); } static const float F44_0 [16 + 32] = { (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0 }; static const float F44_1 [16 + 32] = { /* SNR(w) = 4.843163 dB, SNR = -3.192134 dB */ (float) 0.85018292704024355931, (float) 0.29089597350995344721, (float)-0.05021866022121039450, (float)-0.23545456294599161833, (float)-0.58362726442227032096, (float)-0.67038978965193036429, (float)-0.38566861572833459221, (float)-0.15218663390367969967, (float)-0.02577543084864530676, (float) 0.14119295297688728127, (float) 0.22398848581628781612, (float) 0.15401727203382084116, (float) 0.05216161232906000929, (float)-0.00282237820999675451, (float)-0.03042794608323867363, (float)-0.03109780942998826024, (float) 0.85018292704024355931, (float) 0.29089597350995344721, (float)-0.05021866022121039450, (float)-0.23545456294599161833, (float)-0.58362726442227032096, (float)-0.67038978965193036429, (float)-0.38566861572833459221, (float)-0.15218663390367969967, (float)-0.02577543084864530676, (float) 0.14119295297688728127, (float) 0.22398848581628781612, (float) 0.15401727203382084116, (float) 0.05216161232906000929, (float)-0.00282237820999675451, (float)-0.03042794608323867363, (float)-0.03109780942998826024, (float) 0.85018292704024355931, (float) 0.29089597350995344721, (float)-0.05021866022121039450, (float)-0.23545456294599161833, (float)-0.58362726442227032096, (float)-0.67038978965193036429, (float)-0.38566861572833459221, (float)-0.15218663390367969967, (float)-0.02577543084864530676, (float) 0.14119295297688728127, (float) 0.22398848581628781612, (float) 0.15401727203382084116, (float) 0.05216161232906000929, (float)-0.00282237820999675451, (float)-0.03042794608323867363, (float)-0.03109780942998826024, }; static const float F44_2 [16 + 32] = { /* SNR(w) = 10.060213 dB, SNR = -12.766730 dB */ (float) 1.78827593892108555290, (float) 0.95508210637394326553, (float)-0.18447626783899924429, (float)-0.44198126506275016437, (float)-0.88404052492547413497, (float)-1.42218907262407452967, (float)-1.02037566838362314995, (float)-0.34861755756425577264, (float)-0.11490230170431934434, (float) 0.12498899339968611803, (float) 0.38065885268563131927, (float) 0.31883491321310506562, (float) 0.10486838686563442765, (float)-0.03105361685110374845, (float)-0.06450524884075370758, (float)-0.02939198261121969816, (float) 1.78827593892108555290, (float) 0.95508210637394326553, (float)-0.18447626783899924429, (float)-0.44198126506275016437, (float)-0.88404052492547413497, (float)-1.42218907262407452967, (float)-1.02037566838362314995, (float)-0.34861755756425577264, (float)-0.11490230170431934434, (float) 0.12498899339968611803, (float) 0.38065885268563131927, (float) 0.31883491321310506562, (float) 0.10486838686563442765, (float)-0.03105361685110374845, (float)-0.06450524884075370758, (float)-0.02939198261121969816, (float) 1.78827593892108555290, (float) 0.95508210637394326553, (float)-0.18447626783899924429, (float)-0.44198126506275016437, (float)-0.88404052492547413497, (float)-1.42218907262407452967, (float)-1.02037566838362314995, (float)-0.34861755756425577264, (float)-0.11490230170431934434, (float) 0.12498899339968611803, (float) 0.38065885268563131927, (float) 0.31883491321310506562, (float) 0.10486838686563442765, (float)-0.03105361685110374845, (float)-0.06450524884075370758, (float)-0.02939198261121969816, }; static const float F44_3 [16 + 32] = { /* SNR(w) = 15.382598 dB, SNR = -29.402334 dB */ (float) 2.89072132015058161445, (float) 2.68932810943698754106, (float) 0.21083359339410251227, (float)-0.98385073324997617515, (float)-1.11047823227097316719, (float)-2.18954076314139673147, (float)-2.36498032881953056225, (float)-0.95484132880101140785, (float)-0.23924057925542965158, (float)-0.13865235703915925642, (float) 0.43587843191057992846, (float) 0.65903257226026665927, (float) 0.24361815372443152787, (float)-0.00235974960154720097, (float) 0.01844166574603346289, (float) 0.01722945988740875099, (float) 2.89072132015058161445, (float) 2.68932810943698754106, (float) 0.21083359339410251227, (float)-0.98385073324997617515, (float)-1.11047823227097316719, (float)-2.18954076314139673147, (float)-2.36498032881953056225, (float)-0.95484132880101140785, (float)-0.23924057925542965158, (float)-0.13865235703915925642, (float) 0.43587843191057992846, (float) 0.65903257226026665927, (float) 0.24361815372443152787, (float)-0.00235974960154720097, (float) 0.01844166574603346289, (float) 0.01722945988740875099, (float) 2.89072132015058161445, (float) 2.68932810943698754106, (float) 0.21083359339410251227, (float)-0.98385073324997617515, (float)-1.11047823227097316719, (float)-2.18954076314139673147, (float)-2.36498032881953056225, (float)-0.95484132880101140785, (float)-0.23924057925542965158, (float)-0.13865235703915925642, (float) 0.43587843191057992846, (float) 0.65903257226026665927, (float) 0.24361815372443152787, (float)-0.00235974960154720097, (float) 0.01844166574603346289, (float) 0.01722945988740875099 }; static double scalar16_(const float* x, const float* y) { return x[ 0]*y[ 0] + x[ 1]*y[ 1] + x[ 2]*y[ 2] + x[ 3]*y[ 3] + x[ 4]*y[ 4] + x[ 5]*y[ 5] + x[ 6]*y[ 6] + x[ 7]*y[ 7] + x[ 8]*y[ 8] + x[ 9]*y[ 9] + x[10]*y[10] + x[11]*y[11] + x[12]*y[12] + x[13]*y[13] + x[14]*y[14] + x[15]*y[15]; } void FLAC__replaygain_synthesis__init_dither_context(DitherContext *d, int bits, int shapingtype) { static unsigned char default_dither [] = { 92, 92, 88, 84, 81, 78, 74, 67, 0, 0 }; static const float* F [] = { F44_0, F44_1, F44_2, F44_3 }; int index; if (shapingtype < 0) shapingtype = 0; if (shapingtype > 3) shapingtype = 3; d->ShapingType = (NoiseShaping)shapingtype; index = bits - 11 - shapingtype; if (index < 0) index = 0; if (index > 9) index = 9; memset ( d->ErrorHistory , 0, sizeof (d->ErrorHistory ) ); memset ( d->DitherHistory, 0, sizeof (d->DitherHistory) ); d->FilterCoeff = F [shapingtype]; d->Mask = ((FLAC__uint64)-1) << (32 - bits); d->Add = 0.5 * ((1L << (32 - bits)) - 1); d->Dither = 0.01f*default_dither[index] / (((FLAC__int64)1) << bits); d->LastHistoryIndex = 0; } /* * the following is based on parts of wavegain.c */ static FLAC__INLINE FLAC__int64 dither_output_(DitherContext *d, FLAC__bool do_dithering, int shapingtype, int i, double Sum, int k) { double doubletmp, Sum2; FLAC__int64 val; #define ROUND64(x) ( doubletmp = (x) + d->Add + (FLAC__int64)FLAC__I64L(0x001FFFFD80000000), *(FLAC__int64*)(&doubletmp) - (FLAC__int64)FLAC__I64L(0x433FFFFD80000000) ) if(do_dithering) { if(shapingtype == 0) { double tmp = random_equi_(d->Dither); Sum2 = tmp - d->LastRandomNumber [k]; d->LastRandomNumber [k] = (int)tmp; Sum2 = Sum += Sum2; val = ROUND64(Sum2) & d->Mask; } else { Sum2 = random_triangular_(d->Dither) - scalar16_(d->DitherHistory[k], d->FilterCoeff + i); Sum += d->DitherHistory [k] [(-1-i)&15] = (float)Sum2; Sum2 = Sum + scalar16_(d->ErrorHistory [k], d->FilterCoeff + i); val = ROUND64(Sum2) & d->Mask; d->ErrorHistory [k] [(-1-i)&15] = (float)(Sum - val); } return val; } else return ROUND64(Sum); #undef ROUND64 } #if 0 float peak = 0.f, new_peak, factor_clip double scale, dB; ... peak is in the range -32768.0 .. 32767.0 /* calculate factors for ReplayGain and ClippingPrevention */ *track_gain = GetTitleGain() + settings->man_gain; scale = (float) pow(10., *track_gain * 0.05); if(settings->clip_prev) { factor_clip = (float) (32767./( peak + 1)); if(scale < factor_clip) factor_clip = 1.f; else factor_clip /= scale; scale *= factor_clip; } new_peak = (float) peak * scale; dB = 20. * log10(scale); *track_gain = (float) dB; const double scale = pow(10., (double)gain * 0.05); #endif size_t FLAC__replaygain_synthesis__apply_gain(FLAC__byte *data_out, FLAC__bool little_endian_data_out, FLAC__bool unsigned_data_out, const FLAC__int32 * const input[], unsigned wide_samples, unsigned channels, const unsigned source_bps, const unsigned target_bps, const double scale, const FLAC__bool hard_limit, FLAC__bool do_dithering, DitherContext *dither_context) { static const FLAC__int32 conv_factors_[33] = { -1, /* 0 bits-per-sample (not supported) */ -1, /* 1 bits-per-sample (not supported) */ -1, /* 2 bits-per-sample (not supported) */ -1, /* 3 bits-per-sample (not supported) */ 268435456, /* 4 bits-per-sample */ 134217728, /* 5 bits-per-sample */ 67108864, /* 6 bits-per-sample */ 33554432, /* 7 bits-per-sample */ 16777216, /* 8 bits-per-sample */ 8388608, /* 9 bits-per-sample */ 4194304, /* 10 bits-per-sample */ 2097152, /* 11 bits-per-sample */ 1048576, /* 12 bits-per-sample */ 524288, /* 13 bits-per-sample */ 262144, /* 14 bits-per-sample */ 131072, /* 15 bits-per-sample */ 65536, /* 16 bits-per-sample */ 32768, /* 17 bits-per-sample */ 16384, /* 18 bits-per-sample */ 8192, /* 19 bits-per-sample */ 4096, /* 20 bits-per-sample */ 2048, /* 21 bits-per-sample */ 1024, /* 22 bits-per-sample */ 512, /* 23 bits-per-sample */ 256, /* 24 bits-per-sample */ 128, /* 25 bits-per-sample */ 64, /* 26 bits-per-sample */ 32, /* 27 bits-per-sample */ 16, /* 28 bits-per-sample */ 8, /* 29 bits-per-sample */ 4, /* 30 bits-per-sample */ 2, /* 31 bits-per-sample */ 1 /* 32 bits-per-sample */ }; static const FLAC__int64 hard_clip_factors_[33] = { 0, /* 0 bits-per-sample (not supported) */ 0, /* 1 bits-per-sample (not supported) */ 0, /* 2 bits-per-sample (not supported) */ 0, /* 3 bits-per-sample (not supported) */ -8, /* 4 bits-per-sample */ -16, /* 5 bits-per-sample */ -32, /* 6 bits-per-sample */ -64, /* 7 bits-per-sample */ -128, /* 8 bits-per-sample */ -256, /* 9 bits-per-sample */ -512, /* 10 bits-per-sample */ -1024, /* 11 bits-per-sample */ -2048, /* 12 bits-per-sample */ -4096, /* 13 bits-per-sample */ -8192, /* 14 bits-per-sample */ -16384, /* 15 bits-per-sample */ -32768, /* 16 bits-per-sample */ -65536, /* 17 bits-per-sample */ -131072, /* 18 bits-per-sample */ -262144, /* 19 bits-per-sample */ -524288, /* 20 bits-per-sample */ -1048576, /* 21 bits-per-sample */ -2097152, /* 22 bits-per-sample */ -4194304, /* 23 bits-per-sample */ -8388608, /* 24 bits-per-sample */ -16777216, /* 25 bits-per-sample */ -33554432, /* 26 bits-per-sample */ -67108864, /* 27 bits-per-sample */ -134217728, /* 28 bits-per-sample */ -268435456, /* 29 bits-per-sample */ -536870912, /* 30 bits-per-sample */ -1073741824, /* 31 bits-per-sample */ (FLAC__int64)(-1073741824) * 2 /* 32 bits-per-sample */ }; const FLAC__int32 conv_factor = conv_factors_[target_bps]; const FLAC__int64 hard_clip_factor = hard_clip_factors_[target_bps]; /* * The integer input coming in has a varying range based on the * source_bps. We want to normalize it to [-1.0, 1.0) so instead * of doing two multiplies on each sample, we just multiple * 'scale' by 1/(2^(source_bps-1)) */ const double multi_scale = scale / (double)(1u << (source_bps-1)); FLAC__byte * const start = data_out; unsigned i, channel; const FLAC__int32 *input_; double sample; const unsigned bytes_per_sample = target_bps / 8; const unsigned last_history_index = dither_context->LastHistoryIndex; NoiseShaping noise_shaping = dither_context->ShapingType; FLAC__int64 val64; FLAC__int32 val32; FLAC__int32 uval32; const FLAC__uint32 twiggle = 1u << (target_bps - 1); FLAC__ASSERT(channels > 0 && channels <= FLAC_SHARE__MAX_SUPPORTED_CHANNELS); FLAC__ASSERT(source_bps >= 4); FLAC__ASSERT(target_bps >= 4); FLAC__ASSERT(source_bps <= 32); FLAC__ASSERT(target_bps < 32); FLAC__ASSERT((target_bps & 7) == 0); for(channel = 0; channel < channels; channel++) { const unsigned incr = bytes_per_sample * channels; data_out = start + bytes_per_sample * channel; input_ = input[channel]; for(i = 0; i < wide_samples; i++, data_out += incr) { sample = (double)input_[i] * multi_scale; if(hard_limit) { /* hard 6dB limiting */ if(sample < -0.5) sample = tanh((sample + 0.5) / (1-0.5)) * (1-0.5) - 0.5; else if(sample > 0.5) sample = tanh((sample - 0.5) / (1-0.5)) * (1-0.5) + 0.5; } sample *= 2147483647.f; val64 = dither_output_(dither_context, do_dithering, noise_shaping, (i + last_history_index) % 32, sample, channel) / conv_factor; val32 = (FLAC__int32)val64; if(val64 >= -hard_clip_factor) val32 = (FLAC__int32)(-(hard_clip_factor+1)); else if(val64 < hard_clip_factor) val32 = (FLAC__int32)hard_clip_factor; uval32 = (FLAC__uint32)val32; if (unsigned_data_out) uval32 ^= twiggle; if (little_endian_data_out) { switch(target_bps) { case 24: data_out[2] = (FLAC__byte)(uval32 >> 16); /* fall through */ case 16: data_out[1] = (FLAC__byte)(uval32 >> 8); /* fall through */ case 8: data_out[0] = (FLAC__byte)uval32; break; } } else { switch(target_bps) { case 24: data_out[0] = (FLAC__byte)(uval32 >> 16); data_out[1] = (FLAC__byte)(uval32 >> 8); data_out[2] = (FLAC__byte)uval32; break; case 16: data_out[0] = (FLAC__byte)(uval32 >> 8); data_out[1] = (FLAC__byte)uval32; break; case 8: data_out[0] = (FLAC__byte)uval32; break; } } } } dither_context->LastHistoryIndex = (last_history_index + wide_samples) % 32; return wide_samples * channels * (target_bps/8); }