ce188d4d |
1 | /* |
2 | * ReplayGainAnalysis - analyzes input samples and give the recommended dB change |
3 | * Copyright (C) 2001 David Robinson and Glen Sawyer |
4 | * |
5 | * This library is free software; you can redistribute it and/or |
6 | * modify it under the terms of the GNU Lesser General Public |
7 | * License as published by the Free Software Foundation; either |
8 | * version 2.1 of the License, or (at your option) any later version. |
9 | * |
10 | * This library is distributed in the hope that it will be useful, |
11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
13 | * Lesser General Public License for more details. |
14 | * |
15 | * You should have received a copy of the GNU Lesser General Public |
16 | * License along with this library; if not, write to the Free Software |
17 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
18 | * |
19 | * concept and filter values by David Robinson (David@Robinson.org) |
20 | * -- blame him if you think the idea is flawed |
21 | * original coding by Glen Sawyer (glensawyer@hotmail.com) |
22 | * -- blame him if you think this runs too slowly, or the coding is otherwise flawed |
23 | * |
24 | * lots of code improvements by Frank Klemm ( http://www.uni-jena.de/~pfk/mpp/ ) |
25 | * -- credit him for all the _good_ programming ;) |
26 | * |
27 | * minor cosmetic tweaks to integrate with FLAC by Josh Coalson |
28 | * |
29 | * |
30 | * For an explanation of the concepts and the basic algorithms involved, go to: |
31 | * http://www.replaygain.org/ |
32 | */ |
33 | |
34 | /* |
35 | * Here's the deal. Call |
36 | * |
37 | * InitGainAnalysis ( long samplefreq ); |
38 | * |
39 | * to initialize everything. Call |
40 | * |
41 | * AnalyzeSamples ( const flac_float_t* left_samples, |
42 | * const flac_float_t* right_samples, |
43 | * size_t num_samples, |
44 | * int num_channels ); |
45 | * |
46 | * as many times as you want, with as many or as few samples as you want. |
47 | * If mono, pass the sample buffer in through left_samples, leave |
48 | * right_samples NULL, and make sure num_channels = 1. |
49 | * |
50 | * GetTitleGain() |
51 | * |
52 | * will return the recommended dB level change for all samples analyzed |
53 | * SINCE THE LAST TIME you called GetTitleGain() OR InitGainAnalysis(). |
54 | * |
55 | * GetAlbumGain() |
56 | * |
57 | * will return the recommended dB level change for all samples analyzed |
58 | * since InitGainAnalysis() was called and finalized with GetTitleGain(). |
59 | * |
60 | * Pseudo-code to process an album: |
61 | * |
62 | * flac_float_t l_samples [4096]; |
63 | * flac_float_t r_samples [4096]; |
64 | * size_t num_samples; |
65 | * unsigned int num_songs; |
66 | * unsigned int i; |
67 | * |
68 | * InitGainAnalysis ( 44100 ); |
69 | * for ( i = 1; i <= num_songs; i++ ) { |
70 | * while ( ( num_samples = getSongSamples ( song[i], left_samples, right_samples ) ) > 0 ) |
71 | * AnalyzeSamples ( left_samples, right_samples, num_samples, 2 ); |
72 | * fprintf ("Recommended dB change for song %2d: %+6.2f dB\n", i, GetTitleGain() ); |
73 | * } |
74 | * fprintf ("Recommended dB change for whole album: %+6.2f dB\n", GetAlbumGain() ); |
75 | */ |
76 | |
77 | /* |
78 | * So here's the main source of potential code confusion: |
79 | * |
80 | * The filters applied to the incoming samples are IIR filters, |
81 | * meaning they rely on up to <filter order> number of previous samples |
82 | * AND up to <filter order> number of previous filtered samples. |
83 | * |
84 | * I set up the AnalyzeSamples routine to minimize memory usage and interface |
85 | * complexity. The speed isn't compromised too much (I don't think), but the |
86 | * internal complexity is higher than it should be for such a relatively |
87 | * simple routine. |
88 | * |
89 | * Optimization/clarity suggestions are welcome. |
90 | */ |
91 | |
92 | #ifdef HAVE_CONFIG_H |
93 | # include <config.h> |
94 | #endif |
95 | |
96 | #include <stdio.h> |
97 | #include <stdlib.h> |
98 | #include <string.h> |
99 | #include <math.h> |
100 | #include "share/alloc.h" |
101 | #include "share/compat.h" |
102 | #include "share/replaygain_analysis.h" |
103 | |
104 | flac_float_t ReplayGainReferenceLoudness = 89.0; /* in dB SPL */ |
105 | |
106 | #define YULE_ORDER 10 |
107 | #define BUTTER_ORDER 2 |
108 | #define RMS_PERCENTILE 0.95 /* percentile which is louder than the proposed level */ |
109 | #define RMS_WINDOW_TIME 50 /* Time slice size [ms] */ |
110 | #define STEPS_per_dB 100. /* Table entries per dB */ |
111 | #define MAX_dB 120. /* Table entries for 0...MAX_dB (normal max. values are 70...80 dB) */ |
112 | |
113 | #define MAX_ORDER (BUTTER_ORDER > YULE_ORDER ? BUTTER_ORDER : YULE_ORDER) |
114 | #define PINK_REF 64.82 /* 298640883795 */ /* calibration value */ |
115 | |
116 | static flac_float_t linprebuf [MAX_ORDER * 2]; |
117 | static flac_float_t* linpre; /* left input samples, with pre-buffer */ |
118 | static flac_float_t* lstepbuf; |
119 | static flac_float_t* lstep; /* left "first step" (i.e. post first filter) samples */ |
120 | static flac_float_t* loutbuf; |
121 | static flac_float_t* lout; /* left "out" (i.e. post second filter) samples */ |
122 | static flac_float_t rinprebuf [MAX_ORDER * 2]; |
123 | static flac_float_t* rinpre; /* right input samples ... */ |
124 | static flac_float_t* rstepbuf; |
125 | static flac_float_t* rstep; |
126 | static flac_float_t* routbuf; |
127 | static flac_float_t* rout; |
128 | static unsigned int sampleWindow; /* number of samples required to reach number of milliseconds required for RMS window */ |
129 | static unsigned long totsamp; |
130 | static double lsum; |
131 | static double rsum; |
132 | #if 0 |
133 | static uint32_t A [(size_t)(STEPS_per_dB * MAX_dB)]; |
134 | static uint32_t B [(size_t)(STEPS_per_dB * MAX_dB)]; |
135 | #else |
136 | /* [JEC] Solaris Forte compiler doesn't like float calc in array indices */ |
137 | static uint32_t A [120 * 100]; |
138 | static uint32_t B [120 * 100]; |
139 | #endif |
140 | |
141 | #ifdef _MSC_VER |
142 | #pragma warning ( disable : 4305 ) |
143 | #endif |
144 | |
145 | struct ReplayGainFilter { |
146 | long rate; |
147 | unsigned downsample; |
148 | flac_float_t BYule[YULE_ORDER+1]; |
149 | flac_float_t AYule[YULE_ORDER+1]; |
150 | flac_float_t BButter[BUTTER_ORDER+1]; |
151 | flac_float_t AButter[BUTTER_ORDER+1]; |
152 | }; |
153 | |
154 | static struct ReplayGainFilter *replaygainfilter; |
155 | |
156 | static const struct ReplayGainFilter ReplayGainFilters[] = { |
157 | |
158 | { |
159 | 48000, 0, /* ORIGINAL */ |
160 | { 0.03857599435200, -0.02160367184185, -0.00123395316851, -0.00009291677959, -0.01655260341619, 0.02161526843274, -0.02074045215285, 0.00594298065125, 0.00306428023191, 0.00012025322027, 0.00288463683916 }, |
161 | { 1.00000000000000, -3.84664617118067, 7.81501653005538, -11.34170355132042, 13.05504219327545, -12.28759895145294, 9.48293806319790, -5.87257861775999, 2.75465861874613, -0.86984376593551, 0.13919314567432 }, |
162 | { 0.98621192462708, -1.97242384925416, 0.98621192462708 }, |
163 | { 1.00000000000000, -1.97223372919527, 0.97261396931306 }, |
164 | }, |
165 | |
166 | { |
167 | 44100, 0, /* ORIGINAL */ |
168 | { 0.05418656406430, -0.02911007808948, -0.00848709379851, -0.00851165645469, -0.00834990904936, 0.02245293253339, -0.02596338512915, 0.01624864962975, -0.00240879051584, 0.00674613682247, -0.00187763777362 }, |
169 | { 1.00000000000000, -3.47845948550071, 6.36317777566148, -8.54751527471874, 9.47693607801280, -8.81498681370155, 6.85401540936998, -4.39470996079559, 2.19611684890774, -0.75104302451432, 0.13149317958808 }, |
170 | { 0.98500175787242, -1.97000351574484, 0.98500175787242 }, |
171 | { 1.00000000000000, -1.96977855582618, 0.97022847566350 }, |
172 | }, |
173 | |
174 | { |
175 | 37800, 0, |
176 | { 0.10296717174470, -0.04877975583256, -0.02878009075237, -0.03519509188311, 0.02888717172493, -0.00609872684844, 0.00209851217112, 0.00911704668543, 0.01154404718589, -0.00630293688700, 0.00107527155228 }, |
177 | { 1.00000000000000, -2.64848054923531, 3.58406058405771, -3.83794914179161, 3.90142345804575, -3.50179818637243, 2.67085284083076, -1.82581142372418, 1.09530368139801, -0.47689017820395, 0.11171431535905 }, |
178 | { 0.98252400815195, -1.96504801630391, 0.98252400815195 }, |
179 | { 1.00000000000000, -1.96474258269041, 0.96535344991740 }, |
180 | }, |
181 | |
182 | { |
183 | 36000, 0, |
184 | { 0.11572297028613, -0.04120916051252, -0.04977731768022, -0.01047308680426, 0.00750863219157, 0.00055507694408, 0.00140344192886, 0.01286095246036, 0.00998223033885, -0.00725013810661, 0.00326503346879 }, |
185 | { 1.00000000000000, -2.43606802820871, 3.01907406973844, -2.90372016038192, 2.67947188094303, -2.17606479220391, 1.44912956803015, -0.87785765549050, 0.53592202672557, -0.26469344817509, 0.07495878059717 }, |
186 | { 0.98165826840326, -1.96331653680652, 0.98165826840326 }, |
187 | { 1.00000000000000, -1.96298008938934, 0.96365298422371 }, |
188 | }, |
189 | |
190 | { |
191 | 32000, 0, /* ORIGINAL */ |
192 | { 0.15457299681924, -0.09331049056315, -0.06247880153653, 0.02163541888798, -0.05588393329856, 0.04781476674921, 0.00222312597743, 0.03174092540049, -0.01390589421898, 0.00651420667831, -0.00881362733839 }, |
193 | { 1.00000000000000, -2.37898834973084, 2.84868151156327, -2.64577170229825, 2.23697657451713, -1.67148153367602, 1.00595954808547, -0.45953458054983, 0.16378164858596, -0.05032077717131, 0.02347897407020 }, |
194 | { 0.97938932735214, -1.95877865470428, 0.97938932735214 }, |
195 | { 1.00000000000000, -1.95835380975398, 0.95920349965459 }, |
196 | }, |
197 | |
198 | { |
199 | 28000, 0, |
200 | { 0.23882392323383, -0.22007791534089, -0.06014581950332, 0.05004458058021, -0.03293111254977, 0.02348678189717, 0.04290549799671, -0.00938141862174, 0.00015095146303, -0.00712601540885, -0.00626520210162 }, |
201 | { 1.00000000000000, -2.06894080899139, 1.76944699577212, -0.81404732584187, 0.25418286850232, -0.30340791669762, 0.35616884070937, -0.14967310591258, -0.07024154183279, 0.11078404345174, -0.03551838002425 }, |
202 | { 0.97647981663949, -1.95295963327897, 0.97647981663949 }, |
203 | { 1.00000000000000, -1.95240635772520, 0.95351290883275 }, |
204 | |
205 | }, |
206 | |
207 | { |
208 | 24000, 0, /* ORIGINAL */ |
209 | { 0.30296907319327, -0.22613988682123, -0.08587323730772, 0.03282930172664, -0.00915702933434, -0.02364141202522, -0.00584456039913, 0.06276101321749, -0.00000828086748, 0.00205861885564, -0.02950134983287 }, |
210 | { 1.00000000000000, -1.61273165137247, 1.07977492259970, -0.25656257754070, -0.16276719120440, -0.22638893773906, 0.39120800788284, -0.22138138954925, 0.04500235387352, 0.02005851806501, 0.00302439095741 }, |
211 | { 0.97531843204928, -1.95063686409857, 0.97531843204928 }, |
212 | { 1.00000000000000, -1.95002759149878, 0.95124613669835 }, |
213 | }, |
214 | |
215 | { |
216 | 22050, 0, /* ORIGINAL */ |
217 | { 0.33642304856132, -0.25572241425570, -0.11828570177555, 0.11921148675203, -0.07834489609479, -0.00469977914380, -0.00589500224440, 0.05724228140351, 0.00832043980773, -0.01635381384540, -0.01760176568150 }, |
218 | { 1.00000000000000, -1.49858979367799, 0.87350271418188, 0.12205022308084, -0.80774944671438, 0.47854794562326, -0.12453458140019, -0.04067510197014, 0.08333755284107, -0.04237348025746, 0.02977207319925 }, |
219 | { 0.97316523498161, -1.94633046996323, 0.97316523498161 }, |
220 | { 1.00000000000000, -1.94561023566527, 0.94705070426118 }, |
221 | }, |
222 | |
223 | { |
224 | 18900, 0, |
225 | { 0.38412657295385, -0.44533729608120, 0.20426638066221, -0.28031676047946, 0.31484202614802, -0.26078311203207, 0.12925201224848, -0.01141164696062, 0.03036522115769, -0.03776339305406, 0.00692036603586 }, |
226 | { 1.00000000000000, -1.74403915585708, 1.96686095832499, -2.10081452941881, 1.90753918182846, -1.83814263754422, 1.36971352214969, -0.77883609116398, 0.39266422457649, -0.12529383592986, 0.05424760697665 }, |
227 | { 0.96535326815829, -1.93070653631658, 0.96535326815829 }, |
228 | { 1.00000000000000, -1.92950577983524, 0.93190729279793 }, |
229 | }, |
230 | |
231 | { |
232 | 16000, 0, /* ORIGINAL */ |
233 | { 0.44915256608450, -0.14351757464547, -0.22784394429749, -0.01419140100551, 0.04078262797139, -0.12398163381748, 0.04097565135648, 0.10478503600251, -0.01863887810927, -0.03193428438915, 0.00541907748707 }, |
234 | { 1.00000000000000, -0.62820619233671, 0.29661783706366, -0.37256372942400, 0.00213767857124, -0.42029820170918, 0.22199650564824, 0.00613424350682, 0.06747620744683, 0.05784820375801, 0.03222754072173 }, |
235 | { 0.96454515552826, -1.92909031105652, 0.96454515552826 }, |
236 | { 1.00000000000000, -1.92783286977036, 0.93034775234268 }, |
237 | }, |
238 | |
239 | { |
240 | 12000, 0, /* ORIGINAL */ |
241 | { 0.56619470757641, -0.75464456939302, 0.16242137742230, 0.16744243493672, -0.18901604199609, 0.30931782841830, -0.27562961986224, 0.00647310677246, 0.08647503780351, -0.03788984554840, -0.00588215443421 }, |
242 | { 1.00000000000000, -1.04800335126349, 0.29156311971249, -0.26806001042947, 0.00819999645858, 0.45054734505008, -0.33032403314006, 0.06739368333110, -0.04784254229033, 0.01639907836189, 0.01807364323573 }, |
243 | { 0.96009142950541, -1.92018285901082, 0.96009142950541 }, |
244 | { 1.00000000000000, -1.91858953033784, 0.92177618768381 }, |
245 | }, |
246 | |
247 | { |
248 | 11025, 0, /* ORIGINAL */ |
249 | { 0.58100494960553, -0.53174909058578, -0.14289799034253, 0.17520704835522, 0.02377945217615, 0.15558449135573, -0.25344790059353, 0.01628462406333, 0.06920467763959, -0.03721611395801, -0.00749618797172 }, |
250 | { 1.00000000000000, -0.51035327095184, -0.31863563325245, -0.20256413484477, 0.14728154134330, 0.38952639978999, -0.23313271880868, -0.05246019024463, -0.02505961724053, 0.02442357316099, 0.01818801111503 }, |
251 | { 0.95856916599601, -1.91713833199203, 0.95856916599601 }, |
252 | { 1.00000000000000, -1.91542108074780, 0.91885558323625 }, |
253 | }, |
254 | |
255 | { |
256 | 8000, 0, /* ORIGINAL */ |
257 | { 0.53648789255105, -0.42163034350696, -0.00275953611929, 0.04267842219415, -0.10214864179676, 0.14590772289388, -0.02459864859345, -0.11202315195388, -0.04060034127000, 0.04788665548180, -0.02217936801134 }, |
258 | { 1.00000000000000, -0.25049871956020, -0.43193942311114, -0.03424681017675, -0.04678328784242, 0.26408300200955, 0.15113130533216, -0.17556493366449, -0.18823009262115, 0.05477720428674, 0.04704409688120 }, |
259 | { 0.94597685600279, -1.89195371200558, 0.94597685600279 }, |
260 | { 1.00000000000000, -1.88903307939452, 0.89487434461664 }, |
261 | }, |
262 | |
263 | }; |
264 | |
265 | #ifdef _MSC_VER |
266 | #pragma warning ( default : 4305 ) |
267 | #endif |
268 | |
269 | /* When calling this procedure, make sure that ip[-order] and op[-order] point to real data! */ |
270 | |
271 | static void |
272 | filter ( const flac_float_t* input, flac_float_t* output, size_t nSamples, const flac_float_t* a, const flac_float_t* b, size_t order, unsigned downsample ) |
273 | { |
274 | double y; |
275 | size_t i; |
276 | size_t k; |
277 | |
278 | const flac_float_t* input_head = input; |
279 | const flac_float_t* input_tail; |
280 | |
281 | flac_float_t* output_head = output; |
282 | flac_float_t* output_tail; |
283 | |
284 | for ( i = 0; i < nSamples; i++, input_head += downsample, ++output_head ) { |
285 | |
286 | input_tail = input_head; |
287 | output_tail = output_head; |
288 | |
289 | y = *input_head * b[0]; |
290 | |
291 | for ( k = 1; k <= order; k++ ) { |
292 | input_tail -= downsample; |
293 | --output_tail; |
294 | y += *input_tail * b[k] - *output_tail * a[k]; |
295 | } |
296 | |
297 | output[i] = (flac_float_t)y; |
298 | } |
299 | } |
300 | |
301 | /* returns a INIT_GAIN_ANALYSIS_OK if successful, INIT_GAIN_ANALYSIS_ERROR if not */ |
302 | |
303 | static struct ReplayGainFilter* |
304 | CreateGainFilter ( long samplefreq ) |
305 | { |
306 | unsigned i; |
307 | long maxrate = 0; |
308 | unsigned downsample = 1; |
309 | struct ReplayGainFilter* gainfilter = malloc(sizeof(*gainfilter)); |
310 | |
311 | if ( !gainfilter ) |
312 | return 0; |
313 | |
314 | while (1) { |
315 | for ( i = 0; i < sizeof(ReplayGainFilters)/sizeof(ReplayGainFilters[0]); ++i ) { |
316 | if (maxrate < ReplayGainFilters[i].rate) |
317 | maxrate = ReplayGainFilters[i].rate; |
318 | |
319 | if ( ReplayGainFilters[i].rate == samplefreq ) { |
320 | *gainfilter = ReplayGainFilters[i]; |
321 | gainfilter->downsample = downsample; |
322 | return gainfilter; |
323 | } |
324 | } |
325 | |
326 | if (samplefreq < maxrate) |
327 | break; |
328 | |
329 | while (samplefreq > maxrate) { |
330 | downsample *= 2; |
331 | samplefreq /= 2; |
332 | } |
333 | } |
334 | |
335 | free(gainfilter); |
336 | |
337 | return 0; |
338 | } |
339 | |
340 | static void* |
341 | ReallocateWindowBuffer(unsigned window_size, flac_float_t **window_buffer) |
342 | { |
343 | *window_buffer = safe_realloc_(*window_buffer, sizeof(**window_buffer) * (window_size + MAX_ORDER)); |
344 | return *window_buffer; |
345 | } |
346 | |
347 | static int |
348 | ResetSampleFrequency ( long samplefreq ) { |
349 | int i; |
350 | |
351 | free(replaygainfilter); |
352 | |
353 | replaygainfilter = CreateGainFilter( samplefreq ); |
354 | |
355 | if ( ! replaygainfilter) |
356 | return INIT_GAIN_ANALYSIS_ERROR; |
357 | |
358 | sampleWindow = |
359 | (replaygainfilter->rate * RMS_WINDOW_TIME + 1000-1) / 1000; |
360 | |
361 | if ( ! ReallocateWindowBuffer(sampleWindow, &lstepbuf) || |
362 | ! ReallocateWindowBuffer(sampleWindow, &rstepbuf) || |
363 | ! ReallocateWindowBuffer(sampleWindow, &loutbuf) || |
364 | ! ReallocateWindowBuffer(sampleWindow, &routbuf) ) { |
365 | |
366 | return INIT_GAIN_ANALYSIS_ERROR; |
367 | } |
368 | |
369 | /* zero out initial values */ |
370 | for ( i = 0; i < MAX_ORDER; i++ ) |
371 | linprebuf[i] = lstepbuf[i] = loutbuf[i] = rinprebuf[i] = rstepbuf[i] = routbuf[i] = 0.; |
372 | |
373 | lsum = 0.; |
374 | rsum = 0.; |
375 | totsamp = 0; |
376 | |
377 | memset ( A, 0, sizeof(A) ); |
378 | |
379 | return INIT_GAIN_ANALYSIS_OK; |
380 | } |
381 | |
382 | int |
383 | ValidGainFrequency ( long samplefreq ) |
384 | { |
385 | struct ReplayGainFilter* gainfilter = CreateGainFilter( samplefreq ); |
386 | |
387 | free(gainfilter); |
388 | |
389 | return gainfilter != 0; |
390 | } |
391 | |
392 | int |
393 | InitGainAnalysis ( long samplefreq ) |
394 | { |
395 | if (ResetSampleFrequency(samplefreq) != INIT_GAIN_ANALYSIS_OK) { |
396 | return INIT_GAIN_ANALYSIS_ERROR; |
397 | } |
398 | |
399 | linpre = linprebuf + MAX_ORDER; |
400 | rinpre = rinprebuf + MAX_ORDER; |
401 | lstep = lstepbuf + MAX_ORDER; |
402 | rstep = rstepbuf + MAX_ORDER; |
403 | lout = loutbuf + MAX_ORDER; |
404 | rout = routbuf + MAX_ORDER; |
405 | |
406 | memset ( B, 0, sizeof(B) ); |
407 | |
408 | return INIT_GAIN_ANALYSIS_OK; |
409 | } |
410 | |
411 | /* returns GAIN_ANALYSIS_OK if successful, GAIN_ANALYSIS_ERROR if not */ |
412 | |
413 | int |
414 | AnalyzeSamples ( const flac_float_t* left_samples, const flac_float_t* right_samples, size_t num_samples, int num_channels ) |
415 | { |
416 | unsigned downsample = replaygainfilter->downsample; |
417 | const flac_float_t* curleft; |
418 | const flac_float_t* curright; |
419 | long prebufsamples; |
420 | long batchsamples; |
421 | long cursamples; |
422 | long cursamplepos; |
423 | int i; |
424 | |
425 | num_samples /= downsample; |
426 | |
427 | if ( num_samples == 0 ) |
428 | return GAIN_ANALYSIS_OK; |
429 | |
430 | cursamplepos = 0; |
431 | batchsamples = num_samples; |
432 | |
433 | switch ( num_channels) { |
434 | case 1: right_samples = left_samples; |
435 | case 2: break; |
436 | default: return GAIN_ANALYSIS_ERROR; |
437 | } |
438 | |
439 | prebufsamples = MAX_ORDER; |
440 | if ((size_t) prebufsamples > num_samples) |
441 | prebufsamples = num_samples; |
442 | |
443 | for ( i = 0; i < prebufsamples; ++i ) { |
444 | linprebuf[i+MAX_ORDER] = left_samples [i * downsample]; |
445 | rinprebuf[i+MAX_ORDER] = right_samples[i * downsample]; |
446 | } |
447 | |
448 | while ( batchsamples > 0 ) { |
449 | cursamples = batchsamples > (long)(sampleWindow-totsamp) ? (long)(sampleWindow - totsamp) : batchsamples; |
450 | if ( cursamplepos < MAX_ORDER ) { |
451 | downsample = 1; |
452 | curleft = linpre+cursamplepos; |
453 | curright = rinpre+cursamplepos; |
454 | if (cursamples > MAX_ORDER - cursamplepos ) |
455 | cursamples = MAX_ORDER - cursamplepos; |
456 | } |
457 | else { |
458 | downsample = replaygainfilter->downsample; |
459 | curleft = left_samples + cursamplepos * downsample; |
460 | curright = right_samples + cursamplepos * downsample; |
461 | } |
462 | |
463 | filter ( curleft , lstep + totsamp, cursamples, replaygainfilter->AYule, replaygainfilter->BYule, YULE_ORDER, downsample ); |
464 | filter ( curright, rstep + totsamp, cursamples, replaygainfilter->AYule, replaygainfilter->BYule, YULE_ORDER, downsample ); |
465 | |
466 | filter ( lstep + totsamp, lout + totsamp, cursamples, replaygainfilter->AButter, replaygainfilter->BButter, BUTTER_ORDER, 1 ); |
467 | filter ( rstep + totsamp, rout + totsamp, cursamples, replaygainfilter->AButter, replaygainfilter->BButter, BUTTER_ORDER, 1 ); |
468 | |
469 | for ( i = 0; i < cursamples; i++ ) { /* Get the squared values */ |
470 | lsum += lout [totsamp+i] * lout [totsamp+i]; |
471 | rsum += rout [totsamp+i] * rout [totsamp+i]; |
472 | } |
473 | |
474 | batchsamples -= cursamples; |
475 | cursamplepos += cursamples; |
476 | totsamp += cursamples; |
477 | if ( totsamp == sampleWindow ) { /* Get the Root Mean Square (RMS) for this set of samples */ |
478 | double val = STEPS_per_dB * 10. * log10 ( (lsum+rsum) / totsamp * 0.5 + 1.e-37 ); |
479 | int ival = (int) val; |
480 | if ( ival < 0 ) ival = 0; |
481 | if ( ival >= (int)(sizeof(A)/sizeof(*A)) ) ival = (int)(sizeof(A)/sizeof(*A)) - 1; |
482 | A [ival]++; |
483 | lsum = rsum = 0.; |
484 | memmove ( loutbuf , loutbuf + totsamp, MAX_ORDER * sizeof(flac_float_t) ); |
485 | memmove ( routbuf , routbuf + totsamp, MAX_ORDER * sizeof(flac_float_t) ); |
486 | memmove ( lstepbuf, lstepbuf + totsamp, MAX_ORDER * sizeof(flac_float_t) ); |
487 | memmove ( rstepbuf, rstepbuf + totsamp, MAX_ORDER * sizeof(flac_float_t) ); |
488 | totsamp = 0; |
489 | } |
490 | if ( totsamp > sampleWindow ) /* somehow I really screwed up: Error in programming! Contact author about totsamp > sampleWindow */ |
491 | return GAIN_ANALYSIS_ERROR; |
492 | } |
493 | |
494 | if ( num_samples < MAX_ORDER ) { |
495 | memmove ( linprebuf, linprebuf + num_samples, (MAX_ORDER-num_samples) * sizeof(flac_float_t) ); |
496 | memmove ( rinprebuf, rinprebuf + num_samples, (MAX_ORDER-num_samples) * sizeof(flac_float_t) ); |
497 | memcpy ( linprebuf + MAX_ORDER - num_samples, left_samples, num_samples * sizeof(flac_float_t) ); |
498 | memcpy ( rinprebuf + MAX_ORDER - num_samples, right_samples, num_samples * sizeof(flac_float_t) ); |
499 | } |
500 | else { |
501 | downsample = replaygainfilter->downsample; |
502 | |
503 | left_samples += (num_samples - MAX_ORDER) * downsample; |
504 | right_samples += (num_samples - MAX_ORDER) * downsample; |
505 | |
506 | for ( i = 0; i < MAX_ORDER; ++i ) { |
507 | linprebuf[i] = left_samples [i * downsample]; |
508 | rinprebuf[i] = right_samples[i * downsample]; |
509 | } |
510 | } |
511 | |
512 | return GAIN_ANALYSIS_OK; |
513 | } |
514 | |
515 | |
516 | static flac_float_t |
517 | analyzeResult ( uint32_t* Array, size_t len ) |
518 | { |
519 | uint32_t elems; |
520 | int32_t upper; |
521 | size_t i; |
522 | |
523 | elems = 0; |
524 | for ( i = 0; i < len; i++ ) |
525 | elems += Array[i]; |
526 | if ( elems == 0 ) |
527 | return GAIN_NOT_ENOUGH_SAMPLES; |
528 | |
529 | /* workaround for GCC bug #61423: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61423 */ |
530 | #if 0 |
531 | upper = (int32_t) ceil (elems * (1. - RMS_PERCENTILE)); |
532 | #else |
533 | upper = (int32_t) (elems / 20 + ((elems % 20) ? 1 : 0)); |
534 | #endif |
535 | for ( i = len; i-- > 0; ) { |
536 | if ( (upper -= Array[i]) <= 0 ) |
537 | break; |
538 | } |
539 | |
540 | return (flac_float_t) ((flac_float_t)PINK_REF - (flac_float_t)i / (flac_float_t)STEPS_per_dB); |
541 | } |
542 | |
543 | |
544 | flac_float_t |
545 | GetTitleGain ( void ) |
546 | { |
547 | flac_float_t retval; |
548 | unsigned int i; |
549 | |
550 | retval = analyzeResult ( A, sizeof(A)/sizeof(*A) ); |
551 | |
552 | for ( i = 0; i < sizeof(A)/sizeof(*A); i++ ) { |
553 | B[i] += A[i]; |
554 | A[i] = 0; |
555 | } |
556 | |
557 | for ( i = 0; i < MAX_ORDER; i++ ) |
558 | linprebuf[i] = lstepbuf[i] = loutbuf[i] = rinprebuf[i] = rstepbuf[i] = routbuf[i] = 0.f; |
559 | |
560 | totsamp = 0; |
561 | lsum = rsum = 0.; |
562 | return retval; |
563 | } |
564 | |
565 | |
566 | flac_float_t |
567 | GetAlbumGain ( void ) |
568 | { |
569 | return analyzeResult ( B, sizeof(B)/sizeof(*B) ); |
570 | } |
571 | |
572 | /* end of replaygain_analysis.c */ |