1 /* plugin_common - Routines common to several plugins
2 * Copyright (C) 2002 Josh Coalson
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version 2
7 * of the License, or (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19 * This is an aggregation of pieces of code from John Edwards' WaveGain
20 * program. Mostly cosmetic changes were made; otherwise, the dithering
21 * code is almost untouched and the gain processing was converted from
22 * processing a whole file to processing chunks of samples.
24 * The original copyright notices for WaveGain's dither.c and wavegain.c
28 * (c) 2002 John Edwards
29 * mostly lifted from work by Frank Klemm
30 * random functions for dithering.
33 * Copyright (C) 2002 John Edwards
34 * Additional code by Magnus Holmgren and Gian-Carlo Pascutto
37 #include <string.h> /* for memset() */
39 #include "private/fast_float_math_hack.h"
40 #include "replaygain_synthesis.h"
41 #include "FLAC/assert.h"
44 #define FLAC__INLINE __inline
51 * the following is based on parts of dither.c
56 * This is a simple random number generator with good quality for audio purposes.
57 * It consists of two polycounters with opposite rotation direction and different
58 * periods. The periods are coprime, so the total period is the product of both.
60 * -------------------------------------------------------------------------------------------------
61 * +-> |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|
62 * | -------------------------------------------------------------------------------------------------
64 * | +--+--+--+-XOR-+--------+
66 * +--------------------------------------------------------------------------------------+
68 * -------------------------------------------------------------------------------------------------
69 * |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| <-+
70 * ------------------------------------------------------------------------------------------------- |
72 * +--+----XOR----+--+ |
74 * +----------------------------------------------------------------------------------------+
77 * The first has an period of 3*5*17*257*65537, the second of 7*47*73*178481,
78 * which gives a period of 18.410.713.077.675.721.215. The result is the
79 * XORed values of both generators.
82 static unsigned int random_int_()
84 static const unsigned char parity_[256] = {
85 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,
86 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,
87 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,
88 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,
89 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,
90 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,
91 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,
92 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
94 static unsigned int r1_ = 1;
95 static unsigned int r2_ = 1;
97 unsigned int t1, t2, t3, t4;
99 /* Parity calculation is done via table lookup, this is also available
100 * on CPUs without parity, can be implemented in C and avoid unpredictable
101 * jumps and slow rotate through the carry flag operations.
103 t3 = t1 = r1_; t4 = t2 = r2_;
104 t1 &= 0xF5; t2 >>= 25;
105 t1 = parity_[t1]; t2 &= 0x63;
106 t1 <<= 31; t2 = parity_[t2];
108 return (r1_ = (t3 >> 1) | t1 ) ^ (r2_ = (t4 + t4) | t2 );
111 /* gives a equal distributed random number */
112 /* between -2^31*mult and +2^31*mult */
113 static double random_equi_(double mult)
115 return mult * (int) random_int_();
118 /* gives a triangular distributed random number */
119 /* between -2^32*mult and +2^32*mult */
120 static double random_triangular_(double mult)
122 return mult * ( (double) (int) random_int_() + (double) (int) random_int_() );
126 static const float F44_0 [16 + 32] = {
127 (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0,
128 (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0,
130 (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0,
131 (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0,
133 (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0,
134 (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0, (float)0
138 static const float F44_1 [16 + 32] = { /* SNR(w) = 4.843163 dB, SNR = -3.192134 dB */
139 (float) 0.85018292704024355931, (float) 0.29089597350995344721, (float)-0.05021866022121039450, (float)-0.23545456294599161833,
140 (float)-0.58362726442227032096, (float)-0.67038978965193036429, (float)-0.38566861572833459221, (float)-0.15218663390367969967,
141 (float)-0.02577543084864530676, (float) 0.14119295297688728127, (float) 0.22398848581628781612, (float) 0.15401727203382084116,
142 (float) 0.05216161232906000929, (float)-0.00282237820999675451, (float)-0.03042794608323867363, (float)-0.03109780942998826024,
144 (float) 0.85018292704024355931, (float) 0.29089597350995344721, (float)-0.05021866022121039450, (float)-0.23545456294599161833,
145 (float)-0.58362726442227032096, (float)-0.67038978965193036429, (float)-0.38566861572833459221, (float)-0.15218663390367969967,
146 (float)-0.02577543084864530676, (float) 0.14119295297688728127, (float) 0.22398848581628781612, (float) 0.15401727203382084116,
147 (float) 0.05216161232906000929, (float)-0.00282237820999675451, (float)-0.03042794608323867363, (float)-0.03109780942998826024,
149 (float) 0.85018292704024355931, (float) 0.29089597350995344721, (float)-0.05021866022121039450, (float)-0.23545456294599161833,
150 (float)-0.58362726442227032096, (float)-0.67038978965193036429, (float)-0.38566861572833459221, (float)-0.15218663390367969967,
151 (float)-0.02577543084864530676, (float) 0.14119295297688728127, (float) 0.22398848581628781612, (float) 0.15401727203382084116,
152 (float) 0.05216161232906000929, (float)-0.00282237820999675451, (float)-0.03042794608323867363, (float)-0.03109780942998826024,
156 static const float F44_2 [16 + 32] = { /* SNR(w) = 10.060213 dB, SNR = -12.766730 dB */
157 (float) 1.78827593892108555290, (float) 0.95508210637394326553, (float)-0.18447626783899924429, (float)-0.44198126506275016437,
158 (float)-0.88404052492547413497, (float)-1.42218907262407452967, (float)-1.02037566838362314995, (float)-0.34861755756425577264,
159 (float)-0.11490230170431934434, (float) 0.12498899339968611803, (float) 0.38065885268563131927, (float) 0.31883491321310506562,
160 (float) 0.10486838686563442765, (float)-0.03105361685110374845, (float)-0.06450524884075370758, (float)-0.02939198261121969816,
162 (float) 1.78827593892108555290, (float) 0.95508210637394326553, (float)-0.18447626783899924429, (float)-0.44198126506275016437,
163 (float)-0.88404052492547413497, (float)-1.42218907262407452967, (float)-1.02037566838362314995, (float)-0.34861755756425577264,
164 (float)-0.11490230170431934434, (float) 0.12498899339968611803, (float) 0.38065885268563131927, (float) 0.31883491321310506562,
165 (float) 0.10486838686563442765, (float)-0.03105361685110374845, (float)-0.06450524884075370758, (float)-0.02939198261121969816,
167 (float) 1.78827593892108555290, (float) 0.95508210637394326553, (float)-0.18447626783899924429, (float)-0.44198126506275016437,
168 (float)-0.88404052492547413497, (float)-1.42218907262407452967, (float)-1.02037566838362314995, (float)-0.34861755756425577264,
169 (float)-0.11490230170431934434, (float) 0.12498899339968611803, (float) 0.38065885268563131927, (float) 0.31883491321310506562,
170 (float) 0.10486838686563442765, (float)-0.03105361685110374845, (float)-0.06450524884075370758, (float)-0.02939198261121969816,
174 static const float F44_3 [16 + 32] = { /* SNR(w) = 15.382598 dB, SNR = -29.402334 dB */
175 (float) 2.89072132015058161445, (float) 2.68932810943698754106, (float) 0.21083359339410251227, (float)-0.98385073324997617515,
176 (float)-1.11047823227097316719, (float)-2.18954076314139673147, (float)-2.36498032881953056225, (float)-0.95484132880101140785,
177 (float)-0.23924057925542965158, (float)-0.13865235703915925642, (float) 0.43587843191057992846, (float) 0.65903257226026665927,
178 (float) 0.24361815372443152787, (float)-0.00235974960154720097, (float) 0.01844166574603346289, (float) 0.01722945988740875099,
180 (float) 2.89072132015058161445, (float) 2.68932810943698754106, (float) 0.21083359339410251227, (float)-0.98385073324997617515,
181 (float)-1.11047823227097316719, (float)-2.18954076314139673147, (float)-2.36498032881953056225, (float)-0.95484132880101140785,
182 (float)-0.23924057925542965158, (float)-0.13865235703915925642, (float) 0.43587843191057992846, (float) 0.65903257226026665927,
183 (float) 0.24361815372443152787, (float)-0.00235974960154720097, (float) 0.01844166574603346289, (float) 0.01722945988740875099,
185 (float) 2.89072132015058161445, (float) 2.68932810943698754106, (float) 0.21083359339410251227, (float)-0.98385073324997617515,
186 (float)-1.11047823227097316719, (float)-2.18954076314139673147, (float)-2.36498032881953056225, (float)-0.95484132880101140785,
187 (float)-0.23924057925542965158, (float)-0.13865235703915925642, (float) 0.43587843191057992846, (float) 0.65903257226026665927,
188 (float) 0.24361815372443152787, (float)-0.00235974960154720097, (float) 0.01844166574603346289, (float) 0.01722945988740875099
192 static double scalar16_(const float* x, const float* y)
195 x[ 0]*y[ 0] + x[ 1]*y[ 1] + x[ 2]*y[ 2] + x[ 3]*y[ 3] +
196 x[ 4]*y[ 4] + x[ 5]*y[ 5] + x[ 6]*y[ 6] + x[ 7]*y[ 7] +
197 x[ 8]*y[ 8] + x[ 9]*y[ 9] + x[10]*y[10] + x[11]*y[11] +
198 x[12]*y[12] + x[13]*y[13] + x[14]*y[14] + x[15]*y[15];
202 void FLAC__plugin_common__init_dither_context(DitherContext *d, int bits, int shapingtype)
204 static unsigned char default_dither [] = { 92, 92, 88, 84, 81, 78, 74, 67, 0, 0 };
205 static const float* F [] = { F44_0, F44_1, F44_2, F44_3 };
209 if (shapingtype < 0) shapingtype = 0;
210 if (shapingtype > 3) shapingtype = 3;
211 index = bits - 11 - shapingtype;
212 if (index < 0) index = 0;
213 if (index > 9) index = 9;
215 memset ( d->ErrorHistory , 0, sizeof (d->ErrorHistory ) );
216 memset ( d->DitherHistory, 0, sizeof (d->DitherHistory) );
218 d->FilterCoeff = F [shapingtype];
219 d->Mask = ((FLAC__uint64)-1) << (32 - bits);
220 d->Add = 0.5 * ((1L << (32 - bits)) - 1);
221 d->Dither = 0.01*default_dither[index] / (((FLAC__int64)1) << bits);
225 * the following is based on parts of wavegain.c
228 static FLAC__INLINE FLAC__int64 dither_output_(DitherContext *d, FLAC__bool noise_shaping, int shapingtype, int i, double Sum, int k)
230 double doubletmp, Sum2;
233 #define ROUND64(x) ( doubletmp = (x) + d->Add + (FLAC__int64)0x001FFFFD80000000L, *(FLAC__int64*)(&doubletmp) - (FLAC__int64)0x433FFFFD80000000L )
236 if(shapingtype == 0) {
237 double tmp = random_equi_(d->Dither);
238 Sum2 = tmp - d->LastRandomNumber [k];
239 d->LastRandomNumber [k] = tmp;
241 val = ROUND64(Sum2) & d->Mask;
244 Sum2 = random_triangular_(d->Dither) - scalar16_(d->DitherHistory[k], d->FilterCoeff + i);
245 Sum += d->DitherHistory [k] [(-1-i)&15] = Sum2;
246 Sum2 = Sum + scalar16_(d->ErrorHistory [k], d->FilterCoeff + i);
247 val = ROUND64(Sum2) & d->Mask;
248 d->ErrorHistory [k] [(-1-i)&15] = (float)(Sum - val);
259 Init_Dither (&dither_, settings->outbitwidth, settings->shapingtype)
269 peak is in the range -32768.0 .. 32767.0
271 /* calculate factors for ReplayGain and ClippingPrevention */
272 *track_gain = GetTitleGain() + settings->man_gain;
273 scale = (float) pow(10., *track_gain * 0.05);
274 if(settings->clip_prev) {
275 factor_clip = (float) (32767./( peak + 1));
276 if(scale < factor_clip)
279 factor_clip /= scale;
280 scale *= factor_clip;
282 new_peak = (float) peak * scale;
284 dB = 20. * log10(scale);
285 *track_gain = (float) dB;
287 const double scale = (float) pow(10., (double)gain * 0.05); /*@@@@ why downcast pow() output to float? */
291 PLUGIN_COMMON_API int FLAC__plugin_common_apply_gain(FLAC__byte *data_out, FLAC__int32 *input, unsigned wide_samples, unsigned channels, const unsigned source_bps, const unsigned target_bps, const float scale, const FLAC__bool hard_limit, FLAC__bool do_dithering, NoiseShaping noise_shaping, DitherContext *dither_context)
293 static const FLAC__int32 conv_factors_[33] = {
294 -1, /* 0 bits-per-sample (not supported) */
295 -1, /* 1 bits-per-sample (not supported) */
296 -1, /* 2 bits-per-sample (not supported) */
297 -1, /* 3 bits-per-sample (not supported) */
298 268435456, /* 4 bits-per-sample */
299 134217728, /* 5 bits-per-sample */
300 67108864, /* 6 bits-per-sample */
301 33554432, /* 7 bits-per-sample */
302 16777216, /* 8 bits-per-sample */
303 8388608, /* 9 bits-per-sample */
304 4194304, /* 10 bits-per-sample */
305 2097152, /* 11 bits-per-sample */
306 1048576, /* 12 bits-per-sample */
307 524288, /* 13 bits-per-sample */
308 262144, /* 14 bits-per-sample */
309 131072, /* 15 bits-per-sample */
310 65536, /* 16 bits-per-sample */
311 32768, /* 17 bits-per-sample */
312 16384, /* 18 bits-per-sample */
313 8192, /* 19 bits-per-sample */
314 4096, /* 20 bits-per-sample */
315 2048, /* 21 bits-per-sample */
316 1024, /* 22 bits-per-sample */
317 512, /* 23 bits-per-sample */
318 256, /* 24 bits-per-sample */
319 128, /* 25 bits-per-sample */
320 64, /* 26 bits-per-sample */
321 32, /* 27 bits-per-sample */
322 16, /* 28 bits-per-sample */
323 8, /* 29 bits-per-sample */
324 4, /* 30 bits-per-sample */
325 2, /* 31 bits-per-sample */
326 1 /* 32 bits-per-sample */
328 static const FLAC__int64 hard_clip_factors_[33] = {
329 0, /* 0 bits-per-sample (not supported) */
330 0, /* 1 bits-per-sample (not supported) */
331 0, /* 2 bits-per-sample (not supported) */
332 0, /* 3 bits-per-sample (not supported) */
333 -8, /* 4 bits-per-sample */
334 -16, /* 5 bits-per-sample */
335 -32, /* 6 bits-per-sample */
336 -64, /* 7 bits-per-sample */
337 -128, /* 8 bits-per-sample */
338 -256, /* 9 bits-per-sample */
339 -512, /* 10 bits-per-sample */
340 -1024, /* 11 bits-per-sample */
341 -2048, /* 12 bits-per-sample */
342 -4096, /* 13 bits-per-sample */
343 -8192, /* 14 bits-per-sample */
344 -16384, /* 15 bits-per-sample */
345 -32768, /* 16 bits-per-sample */
346 -65536, /* 17 bits-per-sample */
347 -131072, /* 18 bits-per-sample */
348 -262144, /* 19 bits-per-sample */
349 -524288, /* 20 bits-per-sample */
350 -1048576, /* 21 bits-per-sample */
351 -2097152, /* 22 bits-per-sample */
352 -4194304, /* 23 bits-per-sample */
353 -8388608, /* 24 bits-per-sample */
354 -16777216, /* 25 bits-per-sample */
355 -33554432, /* 26 bits-per-sample */
356 -67108864, /* 27 bits-per-sample */
357 -134217728, /* 28 bits-per-sample */
358 -268435456, /* 29 bits-per-sample */
359 -536870912, /* 30 bits-per-sample */
360 -1073741824, /* 31 bits-per-sample */
361 -2147483648ll /* 32 bits-per-sample */
363 const FLAC__int32 conv_factor = conv_factors_[source_bps];
364 const FLAC__int64 hard_clip_factor = hard_clip_factors_[source_bps];
366 * The integer input coming in has a varying range based on the
367 * source_bps. We want to normalize it to [-1.0, 1.0) so instead
368 * of doing two multiplies on each sample, we just multiple
369 * 'scale' by 1/(2^(source_bps-1))
371 const double multi_scale = scale / (double)(1u << (source_bps-1));
373 FLAC__byte * const start = data_out;
374 const unsigned samples = wide_samples * channels;
375 const unsigned dither_twiggle = channels - 1;
376 unsigned dither_source = 0;
381 FLAC__ASSERT(FLAC_PLUGIN__MAX_SUPPORTED_CHANNELS == 2);
382 FLAC__ASSERT(channels > 0 && channels <= FLAC_PLUGIN__MAX_SUPPORTED_CHANNELS);
383 FLAC__ASSERT(source_bps >= 4);
384 FLAC__ASSERT(target_bps >= 4);
385 FLAC__ASSERT(source_bps <= 32);
386 FLAC__ASSERT(target_bps < 32);
387 FLAC__ASSERT((target_bps & 7) == 0);
390 for(i = 0; i < samples; i++, coeff++) {
391 sample = (double)input[i] * multi_scale;
394 /* hard 6dB limiting */
396 sample = tanh((sample + 0.5) / (1-0.5)) * (1-0.5) - 0.5;
397 else if(sample > 0.5)
398 sample = tanh((sample - 0.5) / (1-0.5)) * (1-0.5) + 0.5;
400 sample *= 2147483647.f;
406 if(coeff >= (32<<dither_twiggle))
409 /* 'coeff>>dither_twiggle' is the same as 'coeff/channels' */
410 val64 = dither_output_(dither_context, do_dithering, noise_shaping, coeff>>dither_twiggle, sample, dither_source) / conv_factor;
412 dither_source ^= dither_twiggle;
414 val32 = (FLAC__int32)val64;
415 if(val64 >= -hard_clip_factor)
416 val32 = (FLAC__int32)(-(hard_clip_factor+1));
417 else if(val64 < hard_clip_factor)
418 val32 = (FLAC__int32)hard_clip_factor;
422 data_out[0] = val32 ^ 0x80;
425 data_out[2] = (FLAC__byte)(val32 >> 16);
428 data_out[1] = (FLAC__byte)(val32 >> 8);
429 data_out[0] = (FLAC__byte)val32;
433 data_out += target_bps/8;
436 return data_out - start;