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diff --git a/lib/rbcodec/codecs/libffmpegFLAC/decoder.c b/lib/rbcodec/codecs/libffmpegFLAC/decoder.c
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1/*
2 * FLAC (Free Lossless Audio Codec) decoder
3 * Copyright (c) 2003 Alex Beregszaszi
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 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 */
19
20/**
21 * @file flac.c
22 * FLAC (Free Lossless Audio Codec) decoder
23 * @author Alex Beregszaszi
24 *
25 * For more information on the FLAC format, visit:
26 * http://flac.sourceforge.net/
27 *
28 * This decoder can be used in 1 of 2 ways: Either raw FLAC data can be fed
29 * through, starting from the initial 'fLaC' signature; or by passing the
30 * 34-byte streaminfo structure through avctx->extradata[_size] followed
31 * by data starting with the 0xFFF8 marker.
32 */
33
34#include <inttypes.h>
35#include <stdbool.h>
36#ifndef BUILD_STANDALONE
37#include "codeclib.h"
38#endif
39
40#include "bitstream.h"
41#include "golomb.h"
42
43#include "decoder.h"
44
45#if defined(CPU_COLDFIRE)
46#include "coldfire.h"
47#elif defined(CPU_ARM)
48#include "arm.h"
49#endif
50
51static const int sample_rate_table[] ICONST_ATTR =
52{ 0, 88200, 176400, 192000,
53 8000, 16000, 22050, 24000, 32000, 44100, 48000, 96000,
54 0, 0, 0, 0 };
55
56static const int sample_size_table[] ICONST_ATTR =
57{ 0, 8, 12, 0, 16, 20, 24, 0 };
58
59static const int blocksize_table[] ICONST_ATTR = {
60 0, 192, 576<<0, 576<<1, 576<<2, 576<<3, 0, 0,
61256<<0, 256<<1, 256<<2, 256<<3, 256<<4, 256<<5, 256<<6, 256<<7
62};
63
64static const uint8_t table_crc8[256] ICONST_ATTR = {
65 0x00, 0x07, 0x0e, 0x09, 0x1c, 0x1b, 0x12, 0x15,
66 0x38, 0x3f, 0x36, 0x31, 0x24, 0x23, 0x2a, 0x2d,
67 0x70, 0x77, 0x7e, 0x79, 0x6c, 0x6b, 0x62, 0x65,
68 0x48, 0x4f, 0x46, 0x41, 0x54, 0x53, 0x5a, 0x5d,
69 0xe0, 0xe7, 0xee, 0xe9, 0xfc, 0xfb, 0xf2, 0xf5,
70 0xd8, 0xdf, 0xd6, 0xd1, 0xc4, 0xc3, 0xca, 0xcd,
71 0x90, 0x97, 0x9e, 0x99, 0x8c, 0x8b, 0x82, 0x85,
72 0xa8, 0xaf, 0xa6, 0xa1, 0xb4, 0xb3, 0xba, 0xbd,
73 0xc7, 0xc0, 0xc9, 0xce, 0xdb, 0xdc, 0xd5, 0xd2,
74 0xff, 0xf8, 0xf1, 0xf6, 0xe3, 0xe4, 0xed, 0xea,
75 0xb7, 0xb0, 0xb9, 0xbe, 0xab, 0xac, 0xa5, 0xa2,
76 0x8f, 0x88, 0x81, 0x86, 0x93, 0x94, 0x9d, 0x9a,
77 0x27, 0x20, 0x29, 0x2e, 0x3b, 0x3c, 0x35, 0x32,
78 0x1f, 0x18, 0x11, 0x16, 0x03, 0x04, 0x0d, 0x0a,
79 0x57, 0x50, 0x59, 0x5e, 0x4b, 0x4c, 0x45, 0x42,
80 0x6f, 0x68, 0x61, 0x66, 0x73, 0x74, 0x7d, 0x7a,
81 0x89, 0x8e, 0x87, 0x80, 0x95, 0x92, 0x9b, 0x9c,
82 0xb1, 0xb6, 0xbf, 0xb8, 0xad, 0xaa, 0xa3, 0xa4,
83 0xf9, 0xfe, 0xf7, 0xf0, 0xe5, 0xe2, 0xeb, 0xec,
84 0xc1, 0xc6, 0xcf, 0xc8, 0xdd, 0xda, 0xd3, 0xd4,
85 0x69, 0x6e, 0x67, 0x60, 0x75, 0x72, 0x7b, 0x7c,
86 0x51, 0x56, 0x5f, 0x58, 0x4d, 0x4a, 0x43, 0x44,
87 0x19, 0x1e, 0x17, 0x10, 0x05, 0x02, 0x0b, 0x0c,
88 0x21, 0x26, 0x2f, 0x28, 0x3d, 0x3a, 0x33, 0x34,
89 0x4e, 0x49, 0x40, 0x47, 0x52, 0x55, 0x5c, 0x5b,
90 0x76, 0x71, 0x78, 0x7f, 0x6a, 0x6d, 0x64, 0x63,
91 0x3e, 0x39, 0x30, 0x37, 0x22, 0x25, 0x2c, 0x2b,
92 0x06, 0x01, 0x08, 0x0f, 0x1a, 0x1d, 0x14, 0x13,
93 0xae, 0xa9, 0xa0, 0xa7, 0xb2, 0xb5, 0xbc, 0xbb,
94 0x96, 0x91, 0x98, 0x9f, 0x8a, 0x8d, 0x84, 0x83,
95 0xde, 0xd9, 0xd0, 0xd7, 0xc2, 0xc5, 0xcc, 0xcb,
96 0xe6, 0xe1, 0xe8, 0xef, 0xfa, 0xfd, 0xf4, 0xf3
97};
98
99static int64_t get_utf8(GetBitContext *gb) ICODE_ATTR_FLAC;
100static int64_t get_utf8(GetBitContext *gb)
101{
102 uint64_t val;
103 int ones=0, bytes;
104
105 while(get_bits1(gb))
106 ones++;
107
108 if (ones==0) bytes=0;
109 else if(ones==1) return -1;
110 else bytes= ones - 1;
111
112 val= get_bits(gb, 7-ones);
113 while(bytes--){
114 const int tmp = get_bits(gb, 8);
115
116 if((tmp>>6) != 2)
117 return -2;
118 val<<=6;
119 val|= tmp&0x3F;
120 }
121 return val;
122}
123
124static int get_crc8(const uint8_t *buf, int count) ICODE_ATTR_FLAC;
125static int get_crc8(const uint8_t *buf, int count)
126{
127 int crc=0;
128 int i;
129
130 for(i=0; i<count; i++){
131 crc = table_crc8[crc ^ buf[i]];
132 }
133
134 return crc;
135}
136
137static int decode_residuals(FLACContext *s, int32_t* decoded, int pred_order) ICODE_ATTR_FLAC;
138static int decode_residuals(FLACContext *s, int32_t* decoded, int pred_order)
139{
140 int i, tmp, partition, method_type, rice_order;
141 int sample = 0, samples;
142
143 method_type = get_bits(&s->gb, 2);
144 if (method_type > 1){
145 //fprintf(stderr,"illegal residual coding method %d\n", method_type);
146 return -3;
147 }
148
149 rice_order = get_bits(&s->gb, 4);
150
151 samples= s->blocksize >> rice_order;
152
153 sample=
154 i= pred_order;
155 for (partition = 0; partition < (1 << rice_order); partition++)
156 {
157 tmp = get_bits(&s->gb, method_type == 0 ? 4 : 5);
158 if (tmp == (method_type == 0 ? 15 : 31))
159 {
160 //fprintf(stderr,"fixed len partition\n");
161 tmp = get_bits(&s->gb, 5);
162 for (; i < samples; i++, sample++)
163 decoded[sample] = get_sbits(&s->gb, tmp);
164 }
165 else
166 {
167 for (; i < samples; i++, sample++){
168 decoded[sample] = get_sr_golomb_flac(&s->gb, tmp, INT_MAX, 0);
169 }
170 }
171 i= 0;
172 }
173
174 return 0;
175}
176
177static int decode_subframe_fixed(FLACContext *s, int32_t* decoded, int pred_order) ICODE_ATTR_FLAC;
178static int decode_subframe_fixed(FLACContext *s, int32_t* decoded, int pred_order)
179{
180 const int blocksize = s->blocksize;
181 int a, b, c, d, i;
182
183 /* warm up samples */
184 for (i = 0; i < pred_order; i++)
185 {
186 decoded[i] = get_sbits(&s->gb, s->curr_bps);
187 }
188
189 if (decode_residuals(s, decoded, pred_order) < 0)
190 return -4;
191
192 a = decoded[pred_order-1];
193 b = a - decoded[pred_order-2];
194 c = b - decoded[pred_order-2] + decoded[pred_order-3];
195 d = c - decoded[pred_order-2] + 2*decoded[pred_order-3] - decoded[pred_order-4];
196
197 switch(pred_order)
198 {
199 case 0:
200 break;
201 case 1:
202 for (i = pred_order; i < blocksize; i++)
203 decoded[i] = a += decoded[i];
204 break;
205 case 2:
206 for (i = pred_order; i < blocksize; i++)
207 decoded[i] = a += b += decoded[i];
208 break;
209 case 3:
210 for (i = pred_order; i < blocksize; i++)
211 decoded[i] = a += b += c += decoded[i];
212 break;
213 case 4:
214 for (i = pred_order; i < blocksize; i++)
215 decoded[i] = a += b += c += d += decoded[i];
216 break;
217 default:
218 return -5;
219 }
220
221 return 0;
222}
223
224static int decode_subframe_lpc(FLACContext *s, int32_t* decoded, int pred_order) ICODE_ATTR_FLAC;
225static int decode_subframe_lpc(FLACContext *s, int32_t* decoded, int pred_order)
226{
227 int sum, i, j;
228 int64_t wsum;
229 int coeff_prec, qlevel;
230 int coeffs[pred_order];
231
232 /* warm up samples */
233 for (i = 0; i < pred_order; i++)
234 {
235 decoded[i] = get_sbits(&s->gb, s->curr_bps);
236 }
237
238 coeff_prec = get_bits(&s->gb, 4) + 1;
239 if (coeff_prec == 16)
240 {
241 //fprintf(stderr,"invalid coeff precision\n");
242 return -6;
243 }
244 qlevel = get_sbits(&s->gb, 5);
245 if (qlevel < 0)
246 {
247 //fprintf(stderr,"qlevel %d not supported, maybe buggy stream\n", qlevel);
248 return -7;
249 }
250
251 for (i = 0; i < pred_order; i++)
252 {
253 coeffs[i] = get_sbits(&s->gb, coeff_prec);
254 }
255
256 if (decode_residuals(s, decoded, pred_order) < 0)
257 return -8;
258
259 if ((s->bps + coeff_prec + av_log2(pred_order)) <= 32) {
260 #if defined(CPU_COLDFIRE)
261 (void)sum;
262 lpc_decode_emac(s->blocksize - pred_order, qlevel, pred_order,
263 decoded + pred_order, coeffs);
264 #elif defined(CPU_ARM)
265 (void)sum;
266 lpc_decode_arm(s->blocksize - pred_order, qlevel, pred_order,
267 decoded + pred_order, coeffs);
268 #else
269 for (i = pred_order; i < s->blocksize; i++)
270 {
271 sum = 0;
272 for (j = 0; j < pred_order; j++)
273 sum += coeffs[j] * decoded[i-j-1];
274 decoded[i] += sum >> qlevel;
275 }
276 #endif
277 } else {
278 #if defined(CPU_COLDFIRE)
279 (void)wsum;
280 (void)j;
281 lpc_decode_emac_wide(s->blocksize - pred_order, qlevel, pred_order,
282 decoded + pred_order, coeffs);
283 #else
284 for (i = pred_order; i < s->blocksize; i++)
285 {
286 wsum = 0;
287 for (j = 0; j < pred_order; j++)
288 wsum += (int64_t)coeffs[j] * (int64_t)decoded[i-j-1];
289 decoded[i] += wsum >> qlevel;
290 }
291 #endif
292 }
293
294 return 0;
295}
296
297static inline int decode_subframe(FLACContext *s, int channel, int32_t* decoded)
298{
299 int type, wasted = 0;
300 int i, tmp;
301
302 s->curr_bps = s->bps;
303 if(channel == 0){
304 if(s->decorrelation == RIGHT_SIDE)
305 s->curr_bps++;
306 }else{
307 if(s->decorrelation == LEFT_SIDE || s->decorrelation == MID_SIDE)
308 s->curr_bps++;
309 }
310
311 if (get_bits1(&s->gb))
312 {
313 //fprintf(stderr,"invalid subframe padding\n");
314 return -9;
315 }
316 type = get_bits(&s->gb, 6);
317// wasted = get_bits1(&s->gb);
318
319// if (wasted)
320// {
321// while (!get_bits1(&s->gb))
322// wasted++;
323// if (wasted)
324// wasted++;
325// s->curr_bps -= wasted;
326// }
327#if 0
328 wasted= 16 - av_log2(show_bits(&s->gb, 17));
329 skip_bits(&s->gb, wasted+1);
330 s->curr_bps -= wasted;
331#else
332 if (get_bits1(&s->gb))
333 {
334 wasted = 1;
335 while (!get_bits1(&s->gb))
336 wasted++;
337 s->curr_bps -= wasted;
338 //fprintf(stderr,"%d wasted bits\n", wasted);
339 }
340#endif
341//FIXME use av_log2 for types
342 if (type == 0)
343 {
344 //fprintf(stderr,"coding type: constant\n");
345 tmp = get_sbits(&s->gb, s->curr_bps);
346 for (i = 0; i < s->blocksize; i++)
347 decoded[i] = tmp;
348 }
349 else if (type == 1)
350 {
351 //fprintf(stderr,"coding type: verbatim\n");
352 for (i = 0; i < s->blocksize; i++)
353 decoded[i] = get_sbits(&s->gb, s->curr_bps);
354 }
355 else if ((type >= 8) && (type <= 12))
356 {
357 //fprintf(stderr,"coding type: fixed\n");
358 if (decode_subframe_fixed(s, decoded, type & ~0x8) < 0)
359 return -10;
360 }
361 else if (type >= 32)
362 {
363 //fprintf(stderr,"coding type: lpc\n");
364 if (decode_subframe_lpc(s, decoded, (type & ~0x20)+1) < 0)
365 return -11;
366 }
367 else
368 {
369 //fprintf(stderr,"Unknown coding type: %d\n",type);
370 return -12;
371 }
372
373 if (wasted)
374 {
375 int i;
376 for (i = 0; i < s->blocksize; i++)
377 decoded[i] <<= wasted;
378 }
379
380 return 0;
381}
382
383static int decode_frame(FLACContext *s,
384 void (*yield)(void)) ICODE_ATTR_FLAC;
385static int decode_frame(FLACContext *s,
386 void (*yield)(void))
387{
388 int blocksize_code, sample_rate_code, sample_size_code, assignment, crc8;
389 int decorrelation, bps, blocksize, samplerate;
390 int res, ch;
391
392 blocksize_code = get_bits(&s->gb, 4);
393
394 sample_rate_code = get_bits(&s->gb, 4);
395
396 assignment = get_bits(&s->gb, 4); /* channel assignment */
397 if (assignment < 8 && s->channels == assignment+1)
398 decorrelation = INDEPENDENT;
399 else if (assignment >=8 && assignment < 11 && s->channels == 2)
400 decorrelation = LEFT_SIDE + assignment - 8;
401 else
402 {
403 return -13;
404 }
405
406 sample_size_code = get_bits(&s->gb, 3);
407 if(sample_size_code == 0)
408 bps= s->bps;
409 else if((sample_size_code != 3) && (sample_size_code != 7))
410 bps = sample_size_table[sample_size_code];
411 else
412 {
413 return -14;
414 }
415
416 if (get_bits1(&s->gb))
417 {
418 return -15;
419 }
420
421 /* Get the samplenumber of the first sample in this block */
422 s->samplenumber=get_utf8(&s->gb);
423
424 /* samplenumber actually contains the frame number for streams
425 with a constant block size - so we multiply by blocksize to
426 get the actual sample number */
427 if (s->min_blocksize == s->max_blocksize) {
428 s->samplenumber*=s->min_blocksize;
429 }
430
431#if 0
432 if (/*((blocksize_code == 6) || (blocksize_code == 7)) &&*/
433 (s->min_blocksize != s->max_blocksize)){
434 }else{
435 }
436#endif
437
438 if (blocksize_code == 0)
439 blocksize = s->min_blocksize;
440 else if (blocksize_code == 6)
441 blocksize = get_bits(&s->gb, 8)+1;
442 else if (blocksize_code == 7)
443 blocksize = get_bits(&s->gb, 16)+1;
444 else
445 blocksize = blocksize_table[blocksize_code];
446
447 if(blocksize > s->max_blocksize){
448 return -16;
449 }
450
451 if (sample_rate_code == 0){
452 samplerate= s->samplerate;
453 }else if ((sample_rate_code < 12))
454 samplerate = sample_rate_table[sample_rate_code];
455 else if (sample_rate_code == 12)
456 samplerate = get_bits(&s->gb, 8) * 1000;
457 else if (sample_rate_code == 13)
458 samplerate = get_bits(&s->gb, 16);
459 else if (sample_rate_code == 14)
460 samplerate = get_bits(&s->gb, 16) * 10;
461 else{
462 return -17;
463 }
464
465 skip_bits(&s->gb, 8);
466 crc8= get_crc8(s->gb.buffer, get_bits_count(&s->gb)/8);
467 if(crc8){
468 return -18;
469 }
470
471 s->blocksize = blocksize;
472 s->samplerate = samplerate;
473 s->bps = bps;
474 s->decorrelation= decorrelation;
475
476 for (ch=0; ch<s->channels; ++ch) {
477 yield();
478 if ((res=decode_subframe(s, ch, s->decoded[ch])) < 0)
479 return res-100;
480 }
481
482 yield();
483 align_get_bits(&s->gb);
484
485 /* frame footer */
486 skip_bits(&s->gb, 16); /* data crc */
487
488 return 0;
489}
490
491static int flac_downmix(FLACContext *s) ICODE_ATTR_FLAC;
492static int flac_downmix(FLACContext *s)
493{
494 int32_t *FL, *FR, *FC, *SB, *RL, *RR;
495 int32_t *outL = s->decoded[0];
496 int32_t *outR = s->decoded[1];
497 int i, scale=FLAC_OUTPUT_DEPTH-s->bps;
498
499 switch(s->channels)
500 {
501 case 3: /* 3.0 channel order: FL FR FC */
502 FL = s->decoded[0];
503 FR = s->decoded[1];
504 FC = s->decoded[2];
505 /* LF = 0.66 LF + 0.33 FC
506 LR = 0.66 LR + 0.33 FC */
507 for (i=0; i<s->blocksize; ++i) {
508 int32_t a = *(FL)*2 + *(FC);
509 int32_t b = *(FR)*2 + *(FC);
510 *outL++ = ((a + (a<<2))>>4) << scale; /* 1/3 ~= 5>>4 */
511 *outR++ = ((b + (b<<2))>>4) << scale; /* 1/3 ~= 5>>4 */
512 FL++; FR++; FC++;
513 }
514 break;
515 case 4: /* 4.0 channel order: FL FR RL RR */
516 FL = s->decoded[0];
517 FR = s->decoded[1];
518 RL = s->decoded[2];
519 RR = s->decoded[3];
520 /* LF = 0.50 LF + 0.50 RL + 0.00 RR
521 LR = 0.50 LR + 0.00 RL + 0.50 RR */
522 for (i=0; i<s->blocksize; ++i) {
523 int32_t a = *(FL) + *(RL);
524 int32_t b = *(FR) + *(RR);
525 *outL++ = (a>>1) << scale;
526 *outR++ = (b>>1) << scale;
527 FL++; FR++; RL++; RR++;
528 }
529 break;
530 case 5: /* 5.0 channel order: FL FR FC RL RR */
531 FL = s->decoded[0];
532 FR = s->decoded[1];
533 FC = s->decoded[2];
534 RL = s->decoded[3];
535 RR = s->decoded[4];
536 /* LF = 0.40 LF + 0.20 FC + 0.40 RL + 0.00 RR
537 LR = 0.40 LR + 0.20 FC + 0.00 RL + 0.40 RR */
538 for (i=0; i<s->blocksize; ++i) {
539 int32_t a = *(FL)*2 + *(FC) + *(RL)*2;
540 int32_t b = *(FR)*2 + *(FC) + *(RR)*2;
541 *outL++ = ((a + (a<<1))>>4) << scale; /* 3>>4 ~= 1/5 */
542 *outR++ = ((b + (b<<1))>>4) << scale; /* 3>>4 ~= 1/5 */
543 FL++; FR++; FC++; RL++; RR++;
544 }
545 break;
546 case 6: /* 5.1 channel order: FL FR FC SUB RL RR */
547 FL = s->decoded[0];
548 FR = s->decoded[1];
549 FC = s->decoded[2];
550 SB = s->decoded[3];
551 RL = s->decoded[4];
552 RR = s->decoded[5];
553 /* LF = 0.33 LF + 0.16 SUB + 0.16 FC + 0.33 RL + 0.00 RR
554 LR = 0.33 LR + 0.16 SUB + 0.16 FC + 0.00 RL + 0.33 RR */
555 for (i=0; i<s->blocksize; ++i) {
556 int32_t a = *(FL)*2 + *(SB) + *(FC) + *(RL)*2;
557 int32_t b = *(FR)*2 + *(SB) + *(FC) + *(RR)*2;
558 *outL++ = ((a + (a<<2))>>5) << scale; /* 5>>5 ~= 1/6 */
559 *outR++ = ((b + (b<<2))>>5) << scale; /* 5>>5 ~= 1/6 */
560 FL++; FR++; SB++; FC++; RL++; RR++;
561 }
562 break;
563 default: /* 1.0 and 2.0 do not need downmix, other formats unknown. */
564 return -501;
565 break;
566 }
567 return 0;
568}
569
570int flac_decode_frame(FLACContext *s,
571 uint8_t *buf, int buf_size,
572 void (*yield)(void))
573{
574 int tmp;
575 int i;
576 int framesize;
577 int scale;
578
579 init_get_bits(&s->gb, buf, buf_size*8);
580
581 tmp = get_bits(&s->gb, 16);
582 if ((tmp & 0xFFFE) != 0xFFF8){
583 return -41;
584 }
585
586 if ((framesize=decode_frame(s,yield)) < 0){
587 s->bitstream_size=0;
588 s->bitstream_index=0;
589 return framesize;
590 }
591
592 yield();
593
594#define DECORRELATE(left, right)\
595 for (i = 0; i < s->blocksize; i++) {\
596 int32_t a = s->decoded[0][i];\
597 int32_t b = s->decoded[1][i];\
598 s->decoded[0][i] = (left) << scale;\
599 s->decoded[1][i] = (right) << scale;\
600 }\
601
602 scale=FLAC_OUTPUT_DEPTH-s->bps;
603 switch(s->decorrelation)
604 {
605 case INDEPENDENT:
606 if (s->channels <= 2) {
607 DECORRELATE(a, b) /* Always decorrelate exactly the two supported channels. */
608 } else {
609 if ((tmp=flac_downmix(s)) != 0)
610 return tmp;
611 }
612 break;
613 case LEFT_SIDE:
614 DECORRELATE(a, a-b)
615 break;
616 case RIGHT_SIDE:
617 DECORRELATE(a+b, b)
618 break;
619 case MID_SIDE:
620 DECORRELATE( (a-=b>>1) + b, a)
621 break;
622 }
623
624 s->framesize = (get_bits_count(&s->gb)+7)>>3;
625
626 return 0;
627}