summaryrefslogtreecommitdiffstats
path: root/media/libopus/src/opus_decoder.c
blob: 6520e748ea832cc1bb2cc0174d533ced13679621 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
/* Copyright (c) 2010 Xiph.Org Foundation, Skype Limited
   Written by Jean-Marc Valin and Koen Vos */
/*
   Redistribution and use in source and binary forms, with or without
   modification, are permitted provided that the following conditions
   are met:

   - Redistributions of source code must retain the above copyright
   notice, this list of conditions and the following disclaimer.

   - Redistributions in binary form must reproduce the above copyright
   notice, this list of conditions and the following disclaimer in the
   documentation and/or other materials provided with the distribution.

   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
   OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
   EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
   PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
   LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

#ifndef OPUS_BUILD
# error "OPUS_BUILD _MUST_ be defined to build Opus. This probably means you need other defines as well, as in a config.h. See the included build files for details."
#endif

#if defined(__GNUC__) && (__GNUC__ >= 2) && !defined(__OPTIMIZE__) && !defined(OPUS_WILL_BE_SLOW)
# pragma message "You appear to be compiling without optimization, if so opus will be very slow."
#endif

#include <stdarg.h>
#include "celt.h"
#include "opus.h"
#include "entdec.h"
#include "modes.h"
#include "API.h"
#include "stack_alloc.h"
#include "float_cast.h"
#include "opus_private.h"
#include "os_support.h"
#include "structs.h"
#include "define.h"
#include "mathops.h"
#include "cpu_support.h"

struct OpusDecoder {
   int          celt_dec_offset;
   int          silk_dec_offset;
   int          channels;
   opus_int32   Fs;          /** Sampling rate (at the API level) */
   silk_DecControlStruct DecControl;
   int          decode_gain;
   int          arch;

   /* Everything beyond this point gets cleared on a reset */
#define OPUS_DECODER_RESET_START stream_channels
   int          stream_channels;

   int          bandwidth;
   int          mode;
   int          prev_mode;
   int          frame_size;
   int          prev_redundancy;
   int          last_packet_duration;
#ifndef FIXED_POINT
   opus_val16   softclip_mem[2];
#endif

   opus_uint32  rangeFinal;
};

#if defined(ENABLE_HARDENING) || defined(ENABLE_ASSERTIONS)
static void validate_opus_decoder(OpusDecoder *st)
{
   celt_assert(st->channels == 1 || st->channels == 2);
   celt_assert(st->Fs == 48000 || st->Fs == 24000 || st->Fs == 16000 || st->Fs == 12000 || st->Fs == 8000);
   celt_assert(st->DecControl.API_sampleRate == st->Fs);
   celt_assert(st->DecControl.internalSampleRate == 0 || st->DecControl.internalSampleRate == 16000 || st->DecControl.internalSampleRate == 12000 || st->DecControl.internalSampleRate == 8000);
   celt_assert(st->DecControl.nChannelsAPI == st->channels);
   celt_assert(st->DecControl.nChannelsInternal == 0 || st->DecControl.nChannelsInternal == 1 || st->DecControl.nChannelsInternal == 2);
   celt_assert(st->DecControl.payloadSize_ms == 0 || st->DecControl.payloadSize_ms == 10 || st->DecControl.payloadSize_ms == 20 || st->DecControl.payloadSize_ms == 40 || st->DecControl.payloadSize_ms == 60);
#ifdef OPUS_ARCHMASK
   celt_assert(st->arch >= 0);
   celt_assert(st->arch <= OPUS_ARCHMASK);
#endif
   celt_assert(st->stream_channels == 1 || st->stream_channels == 2);
}
#define VALIDATE_OPUS_DECODER(st) validate_opus_decoder(st)
#else
#define VALIDATE_OPUS_DECODER(st)
#endif

int opus_decoder_get_size(int channels)
{
   int silkDecSizeBytes, celtDecSizeBytes;
   int ret;
   if (channels<1 || channels > 2)
      return 0;
   ret = silk_Get_Decoder_Size( &silkDecSizeBytes );
   if(ret)
      return 0;
   silkDecSizeBytes = align(silkDecSizeBytes);
   celtDecSizeBytes = celt_decoder_get_size(channels);
   return align(sizeof(OpusDecoder))+silkDecSizeBytes+celtDecSizeBytes;
}

int opus_decoder_init(OpusDecoder *st, opus_int32 Fs, int channels)
{
   void *silk_dec;
   CELTDecoder *celt_dec;
   int ret, silkDecSizeBytes;

   if ((Fs!=48000&&Fs!=24000&&Fs!=16000&&Fs!=12000&&Fs!=8000)
    || (channels!=1&&channels!=2))
      return OPUS_BAD_ARG;

   OPUS_CLEAR((char*)st, opus_decoder_get_size(channels));
   /* Initialize SILK decoder */
   ret = silk_Get_Decoder_Size(&silkDecSizeBytes);
   if (ret)
      return OPUS_INTERNAL_ERROR;

   silkDecSizeBytes = align(silkDecSizeBytes);
   st->silk_dec_offset = align(sizeof(OpusDecoder));
   st->celt_dec_offset = st->silk_dec_offset+silkDecSizeBytes;
   silk_dec = (char*)st+st->silk_dec_offset;
   celt_dec = (CELTDecoder*)((char*)st+st->celt_dec_offset);
   st->stream_channels = st->channels = channels;

   st->Fs = Fs;
   st->DecControl.API_sampleRate = st->Fs;
   st->DecControl.nChannelsAPI      = st->channels;

   /* Reset decoder */
   ret = silk_InitDecoder( silk_dec );
   if(ret)return OPUS_INTERNAL_ERROR;

   /* Initialize CELT decoder */
   ret = celt_decoder_init(celt_dec, Fs, channels);
   if(ret!=OPUS_OK)return OPUS_INTERNAL_ERROR;

   celt_decoder_ctl(celt_dec, CELT_SET_SIGNALLING(0));

   st->prev_mode = 0;
   st->frame_size = Fs/400;
   st->arch = opus_select_arch();
   return OPUS_OK;
}

OpusDecoder *opus_decoder_create(opus_int32 Fs, int channels, int *error)
{
   int ret;
   OpusDecoder *st;
   if ((Fs!=48000&&Fs!=24000&&Fs!=16000&&Fs!=12000&&Fs!=8000)
    || (channels!=1&&channels!=2))
   {
      if (error)
         *error = OPUS_BAD_ARG;
      return NULL;
   }
   st = (OpusDecoder *)opus_alloc(opus_decoder_get_size(channels));
   if (st == NULL)
   {
      if (error)
         *error = OPUS_ALLOC_FAIL;
      return NULL;
   }
   ret = opus_decoder_init(st, Fs, channels);
   if (error)
      *error = ret;
   if (ret != OPUS_OK)
   {
      opus_free(st);
      st = NULL;
   }
   return st;
}

static void smooth_fade(const opus_val16 *in1, const opus_val16 *in2,
      opus_val16 *out, int overlap, int channels,
      const opus_val16 *window, opus_int32 Fs)
{
   int i, c;
   int inc = 48000/Fs;
   for (c=0;c<channels;c++)
   {
      for (i=0;i<overlap;i++)
      {
         opus_val16 w = MULT16_16_Q15(window[i*inc], window[i*inc]);
         out[i*channels+c] = SHR32(MAC16_16(MULT16_16(w,in2[i*channels+c]),
                                   Q15ONE-w, in1[i*channels+c]), 15);
      }
   }
}

static int opus_packet_get_mode(const unsigned char *data)
{
   int mode;
   if (data[0]&0x80)
   {
      mode = MODE_CELT_ONLY;
   } else if ((data[0]&0x60) == 0x60)
   {
      mode = MODE_HYBRID;
   } else {
      mode = MODE_SILK_ONLY;
   }
   return mode;
}

static int opus_decode_frame(OpusDecoder *st, const unsigned char *data,
      opus_int32 len, opus_val16 *pcm, int frame_size, int decode_fec)
{
   void *silk_dec;
   CELTDecoder *celt_dec;
   int i, silk_ret=0, celt_ret=0;
   ec_dec dec;
   opus_int32 silk_frame_size;
   int pcm_silk_size;
   VARDECL(opus_int16, pcm_silk);
   int pcm_transition_silk_size;
   VARDECL(opus_val16, pcm_transition_silk);
   int pcm_transition_celt_size;
   VARDECL(opus_val16, pcm_transition_celt);
   opus_val16 *pcm_transition=NULL;
   int redundant_audio_size;
   VARDECL(opus_val16, redundant_audio);

   int audiosize;
   int mode;
   int bandwidth;
   int transition=0;
   int start_band;
   int redundancy=0;
   int redundancy_bytes = 0;
   int celt_to_silk=0;
   int c;
   int F2_5, F5, F10, F20;
   const opus_val16 *window;
   opus_uint32 redundant_rng = 0;
   int celt_accum;
   ALLOC_STACK;

   silk_dec = (char*)st+st->silk_dec_offset;
   celt_dec = (CELTDecoder*)((char*)st+st->celt_dec_offset);
   F20 = st->Fs/50;
   F10 = F20>>1;
   F5 = F10>>1;
   F2_5 = F5>>1;
   if (frame_size < F2_5)
   {
      RESTORE_STACK;
      return OPUS_BUFFER_TOO_SMALL;
   }
   /* Limit frame_size to avoid excessive stack allocations. */
   frame_size = IMIN(frame_size, st->Fs/25*3);
   /* Payloads of 1 (2 including ToC) or 0 trigger the PLC/DTX */
   if (len<=1)
   {
      data = NULL;
      /* In that case, don't conceal more than what the ToC says */
      frame_size = IMIN(frame_size, st->frame_size);
   }
   if (data != NULL)
   {
      audiosize = st->frame_size;
      mode = st->mode;
      bandwidth = st->bandwidth;
      ec_dec_init(&dec,(unsigned char*)data,len);
   } else {
      audiosize = frame_size;
      /* Run PLC using last used mode (CELT if we ended with CELT redundancy) */
      mode = st->prev_redundancy ? MODE_CELT_ONLY : st->prev_mode;
      bandwidth = 0;

      if (mode == 0)
      {
         /* If we haven't got any packet yet, all we can do is return zeros */
         for (i=0;i<audiosize*st->channels;i++)
            pcm[i] = 0;
         RESTORE_STACK;
         return audiosize;
      }

      /* Avoids trying to run the PLC on sizes other than 2.5 (CELT), 5 (CELT),
         10, or 20 (e.g. 12.5 or 30 ms). */
      if (audiosize > F20)
      {
         do {
            int ret = opus_decode_frame(st, NULL, 0, pcm, IMIN(audiosize, F20), 0);
            if (ret<0)
            {
               RESTORE_STACK;
               return ret;
            }
            pcm += ret*st->channels;
            audiosize -= ret;
         } while (audiosize > 0);
         RESTORE_STACK;
         return frame_size;
      } else if (audiosize < F20)
      {
         if (audiosize > F10)
            audiosize = F10;
         else if (mode != MODE_SILK_ONLY && audiosize > F5 && audiosize < F10)
            audiosize = F5;
      }
   }

   /* In fixed-point, we can tell CELT to do the accumulation on top of the
      SILK PCM buffer. This saves some stack space. */
#ifdef FIXED_POINT
   celt_accum = (mode != MODE_CELT_ONLY) && (frame_size >= F10);
#else
   celt_accum = 0;
#endif

   pcm_transition_silk_size = ALLOC_NONE;
   pcm_transition_celt_size = ALLOC_NONE;
   if (data!=NULL && st->prev_mode > 0 && (
       (mode == MODE_CELT_ONLY && st->prev_mode != MODE_CELT_ONLY && !st->prev_redundancy)
    || (mode != MODE_CELT_ONLY && st->prev_mode == MODE_CELT_ONLY) )
      )
   {
      transition = 1;
      /* Decide where to allocate the stack memory for pcm_transition */
      if (mode == MODE_CELT_ONLY)
         pcm_transition_celt_size = F5*st->channels;
      else
         pcm_transition_silk_size = F5*st->channels;
   }
   ALLOC(pcm_transition_celt, pcm_transition_celt_size, opus_val16);
   if (transition && mode == MODE_CELT_ONLY)
   {
      pcm_transition = pcm_transition_celt;
      opus_decode_frame(st, NULL, 0, pcm_transition, IMIN(F5, audiosize), 0);
   }
   if (audiosize > frame_size)
   {
      /*fprintf(stderr, "PCM buffer too small: %d vs %d (mode = %d)\n", audiosize, frame_size, mode);*/
      RESTORE_STACK;
      return OPUS_BAD_ARG;
   } else {
      frame_size = audiosize;
   }

   /* Don't allocate any memory when in CELT-only mode */
   pcm_silk_size = (mode != MODE_CELT_ONLY && !celt_accum) ? IMAX(F10, frame_size)*st->channels : ALLOC_NONE;
   ALLOC(pcm_silk, pcm_silk_size, opus_int16);

   /* SILK processing */
   if (mode != MODE_CELT_ONLY)
   {
      int lost_flag, decoded_samples;
      opus_int16 *pcm_ptr;
#ifdef FIXED_POINT
      if (celt_accum)
         pcm_ptr = pcm;
      else
#endif
         pcm_ptr = pcm_silk;

      if (st->prev_mode==MODE_CELT_ONLY)
         silk_InitDecoder( silk_dec );

      /* The SILK PLC cannot produce frames of less than 10 ms */
      st->DecControl.payloadSize_ms = IMAX(10, 1000 * audiosize / st->Fs);

      if (data != NULL)
      {
        st->DecControl.nChannelsInternal = st->stream_channels;
        if( mode == MODE_SILK_ONLY ) {
           if( bandwidth == OPUS_BANDWIDTH_NARROWBAND ) {
              st->DecControl.internalSampleRate = 8000;
           } else if( bandwidth == OPUS_BANDWIDTH_MEDIUMBAND ) {
              st->DecControl.internalSampleRate = 12000;
           } else if( bandwidth == OPUS_BANDWIDTH_WIDEBAND ) {
              st->DecControl.internalSampleRate = 16000;
           } else {
              st->DecControl.internalSampleRate = 16000;
              celt_assert( 0 );
           }
        } else {
           /* Hybrid mode */
           st->DecControl.internalSampleRate = 16000;
        }
     }

     lost_flag = data == NULL ? 1 : 2 * decode_fec;
     decoded_samples = 0;
     do {
        /* Call SILK decoder */
        int first_frame = decoded_samples == 0;
        silk_ret = silk_Decode( silk_dec, &st->DecControl,
                                lost_flag, first_frame, &dec, pcm_ptr, &silk_frame_size, st->arch );
        if( silk_ret ) {
           if (lost_flag) {
              /* PLC failure should not be fatal */
              silk_frame_size = frame_size;
              for (i=0;i<frame_size*st->channels;i++)
                 pcm_ptr[i] = 0;
           } else {
             RESTORE_STACK;
             return OPUS_INTERNAL_ERROR;
           }
        }
        pcm_ptr += silk_frame_size * st->channels;
        decoded_samples += silk_frame_size;
      } while( decoded_samples < frame_size );
   }

   start_band = 0;
   if (!decode_fec && mode != MODE_CELT_ONLY && data != NULL
    && ec_tell(&dec)+17+20*(mode == MODE_HYBRID) <= 8*len)
   {
      /* Check if we have a redundant 0-8 kHz band */
      if (mode == MODE_HYBRID)
         redundancy = ec_dec_bit_logp(&dec, 12);
      else
         redundancy = 1;
      if (redundancy)
      {
         celt_to_silk = ec_dec_bit_logp(&dec, 1);
         /* redundancy_bytes will be at least two, in the non-hybrid
            case due to the ec_tell() check above */
         redundancy_bytes = mode==MODE_HYBRID ?
               (opus_int32)ec_dec_uint(&dec, 256)+2 :
               len-((ec_tell(&dec)+7)>>3);
         len -= redundancy_bytes;
         /* This is a sanity check. It should never happen for a valid
            packet, so the exact behaviour is not normative. */
         if (len*8 < ec_tell(&dec))
         {
            len = 0;
            redundancy_bytes = 0;
            redundancy = 0;
         }
         /* Shrink decoder because of raw bits */
         dec.storage -= redundancy_bytes;
      }
   }
   if (mode != MODE_CELT_ONLY)
      start_band = 17;

   if (redundancy)
   {
      transition = 0;
      pcm_transition_silk_size=ALLOC_NONE;
   }

   ALLOC(pcm_transition_silk, pcm_transition_silk_size, opus_val16);

   if (transition && mode != MODE_CELT_ONLY)
   {
      pcm_transition = pcm_transition_silk;
      opus_decode_frame(st, NULL, 0, pcm_transition, IMIN(F5, audiosize), 0);
   }


   if (bandwidth)
   {
      int endband=21;

      switch(bandwidth)
      {
      case OPUS_BANDWIDTH_NARROWBAND:
         endband = 13;
         break;
      case OPUS_BANDWIDTH_MEDIUMBAND:
      case OPUS_BANDWIDTH_WIDEBAND:
         endband = 17;
         break;
      case OPUS_BANDWIDTH_SUPERWIDEBAND:
         endband = 19;
         break;
      case OPUS_BANDWIDTH_FULLBAND:
         endband = 21;
         break;
      default:
         celt_assert(0);
         break;
      }
      MUST_SUCCEED(celt_decoder_ctl(celt_dec, CELT_SET_END_BAND(endband)));
   }
   MUST_SUCCEED(celt_decoder_ctl(celt_dec, CELT_SET_CHANNELS(st->stream_channels)));

   /* Only allocation memory for redundancy if/when needed */
   redundant_audio_size = redundancy ? F5*st->channels : ALLOC_NONE;
   ALLOC(redundant_audio, redundant_audio_size, opus_val16);

   /* 5 ms redundant frame for CELT->SILK*/
   if (redundancy && celt_to_silk)
   {
      /* If the previous frame did not use CELT (the first redundancy frame in
         a transition from SILK may have been lost) then the CELT decoder is
         stale at this point and the redundancy audio is not useful, however
         the final range is still needed (for testing), so the redundancy is
         always decoded but the decoded audio may not be used */
      MUST_SUCCEED(celt_decoder_ctl(celt_dec, CELT_SET_START_BAND(0)));
      celt_decode_with_ec(celt_dec, data+len, redundancy_bytes,
                          redundant_audio, F5, NULL, 0);
      MUST_SUCCEED(celt_decoder_ctl(celt_dec, OPUS_GET_FINAL_RANGE(&redundant_rng)));
   }

   /* MUST be after PLC */
   MUST_SUCCEED(celt_decoder_ctl(celt_dec, CELT_SET_START_BAND(start_band)));

   if (mode != MODE_SILK_ONLY)
   {
      int celt_frame_size = IMIN(F20, frame_size);
      /* Make sure to discard any previous CELT state */
      if (mode != st->prev_mode && st->prev_mode > 0 && !st->prev_redundancy)
         MUST_SUCCEED(celt_decoder_ctl(celt_dec, OPUS_RESET_STATE));
      /* Decode CELT */
      celt_ret = celt_decode_with_ec(celt_dec, decode_fec ? NULL : data,
                                     len, pcm, celt_frame_size, &dec, celt_accum);
   } else {
      unsigned char silence[2] = {0xFF, 0xFF};
      if (!celt_accum)
      {
         for (i=0;i<frame_size*st->channels;i++)
            pcm[i] = 0;
      }
      /* For hybrid -> SILK transitions, we let the CELT MDCT
         do a fade-out by decoding a silence frame */
      if (st->prev_mode == MODE_HYBRID && !(redundancy && celt_to_silk && st->prev_redundancy) )
      {
         MUST_SUCCEED(celt_decoder_ctl(celt_dec, CELT_SET_START_BAND(0)));
         celt_decode_with_ec(celt_dec, silence, 2, pcm, F2_5, NULL, celt_accum);
      }
   }

   if (mode != MODE_CELT_ONLY && !celt_accum)
   {
#ifdef FIXED_POINT
      for (i=0;i<frame_size*st->channels;i++)
         pcm[i] = SAT16(ADD32(pcm[i], pcm_silk[i]));
#else
      for (i=0;i<frame_size*st->channels;i++)
         pcm[i] = pcm[i] + (opus_val16)((1.f/32768.f)*pcm_silk[i]);
#endif
   }

   {
      const CELTMode *celt_mode;
      MUST_SUCCEED(celt_decoder_ctl(celt_dec, CELT_GET_MODE(&celt_mode)));
      window = celt_mode->window;
   }

   /* 5 ms redundant frame for SILK->CELT */
   if (redundancy && !celt_to_silk)
   {
      MUST_SUCCEED(celt_decoder_ctl(celt_dec, OPUS_RESET_STATE));
      MUST_SUCCEED(celt_decoder_ctl(celt_dec, CELT_SET_START_BAND(0)));

      celt_decode_with_ec(celt_dec, data+len, redundancy_bytes, redundant_audio, F5, NULL, 0);
      MUST_SUCCEED(celt_decoder_ctl(celt_dec, OPUS_GET_FINAL_RANGE(&redundant_rng)));
      smooth_fade(pcm+st->channels*(frame_size-F2_5), redundant_audio+st->channels*F2_5,
                  pcm+st->channels*(frame_size-F2_5), F2_5, st->channels, window, st->Fs);
   }
   /* 5ms redundant frame for CELT->SILK; ignore if the previous frame did not
      use CELT (the first redundancy frame in a transition from SILK may have
      been lost) */
   if (redundancy && celt_to_silk && (st->prev_mode != MODE_SILK_ONLY || st->prev_redundancy))
   {
      for (c=0;c<st->channels;c++)
      {
         for (i=0;i<F2_5;i++)
            pcm[st->channels*i+c] = redundant_audio[st->channels*i+c];
      }
      smooth_fade(redundant_audio+st->channels*F2_5, pcm+st->channels*F2_5,
                  pcm+st->channels*F2_5, F2_5, st->channels, window, st->Fs);
   }
   if (transition)
   {
      if (audiosize >= F5)
      {
         for (i=0;i<st->channels*F2_5;i++)
            pcm[i] = pcm_transition[i];
         smooth_fade(pcm_transition+st->channels*F2_5, pcm+st->channels*F2_5,
                     pcm+st->channels*F2_5, F2_5,
                     st->channels, window, st->Fs);
      } else {
         /* Not enough time to do a clean transition, but we do it anyway
            This will not preserve amplitude perfectly and may introduce
            a bit of temporal aliasing, but it shouldn't be too bad and
            that's pretty much the best we can do. In any case, generating this
            transition it pretty silly in the first place */
         smooth_fade(pcm_transition, pcm,
                     pcm, F2_5,
                     st->channels, window, st->Fs);
      }
   }

   if(st->decode_gain)
   {
      opus_val32 gain;
      gain = celt_exp2(MULT16_16_P15(QCONST16(6.48814081e-4f, 25), st->decode_gain));
      for (i=0;i<frame_size*st->channels;i++)
      {
         opus_val32 x;
         x = MULT16_32_P16(pcm[i],gain);
         pcm[i] = SATURATE(x, 32767);
      }
   }

   if (len <= 1)
      st->rangeFinal = 0;
   else
      st->rangeFinal = dec.rng ^ redundant_rng;

   st->prev_mode = mode;
   st->prev_redundancy = redundancy && !celt_to_silk;

   if (celt_ret>=0)
   {
      if (OPUS_CHECK_ARRAY(pcm, audiosize*st->channels))
         OPUS_PRINT_INT(audiosize);
   }

   RESTORE_STACK;
   return celt_ret < 0 ? celt_ret : audiosize;

}

int opus_decode_native(OpusDecoder *st, const unsigned char *data,
      opus_int32 len, opus_val16 *pcm, int frame_size, int decode_fec,
      int self_delimited, opus_int32 *packet_offset, int soft_clip)
{
   int i, nb_samples;
   int count, offset;
   unsigned char toc;
   int packet_frame_size, packet_bandwidth, packet_mode, packet_stream_channels;
   /* 48 x 2.5 ms = 120 ms */
   opus_int16 size[48];
   VALIDATE_OPUS_DECODER(st);
   if (decode_fec<0 || decode_fec>1)
      return OPUS_BAD_ARG;
   /* For FEC/PLC, frame_size has to be to have a multiple of 2.5 ms */
   if ((decode_fec || len==0 || data==NULL) && frame_size%(st->Fs/400)!=0)
      return OPUS_BAD_ARG;
   if (len==0 || data==NULL)
   {
      int pcm_count=0;
      do {
         int ret;
         ret = opus_decode_frame(st, NULL, 0, pcm+pcm_count*st->channels, frame_size-pcm_count, 0);
         if (ret<0)
            return ret;
         pcm_count += ret;
      } while (pcm_count < frame_size);
      celt_assert(pcm_count == frame_size);
      if (OPUS_CHECK_ARRAY(pcm, pcm_count*st->channels))
         OPUS_PRINT_INT(pcm_count);
      st->last_packet_duration = pcm_count;
      return pcm_count;
   } else if (len<0)
      return OPUS_BAD_ARG;

   packet_mode = opus_packet_get_mode(data);
   packet_bandwidth = opus_packet_get_bandwidth(data);
   packet_frame_size = opus_packet_get_samples_per_frame(data, st->Fs);
   packet_stream_channels = opus_packet_get_nb_channels(data);

   count = opus_packet_parse_impl(data, len, self_delimited, &toc, NULL,
                                  size, &offset, packet_offset);
   if (count<0)
      return count;

   data += offset;

   if (decode_fec)
   {
      int duration_copy;
      int ret;
      /* If no FEC can be present, run the PLC (recursive call) */
      if (frame_size < packet_frame_size || packet_mode == MODE_CELT_ONLY || st->mode == MODE_CELT_ONLY)
         return opus_decode_native(st, NULL, 0, pcm, frame_size, 0, 0, NULL, soft_clip);
      /* Otherwise, run the PLC on everything except the size for which we might have FEC */
      duration_copy = st->last_packet_duration;
      if (frame_size-packet_frame_size!=0)
      {
         ret = opus_decode_native(st, NULL, 0, pcm, frame_size-packet_frame_size, 0, 0, NULL, soft_clip);
         if (ret<0)
         {
            st->last_packet_duration = duration_copy;
            return ret;
         }
         celt_assert(ret==frame_size-packet_frame_size);
      }
      /* Complete with FEC */
      st->mode = packet_mode;
      st->bandwidth = packet_bandwidth;
      st->frame_size = packet_frame_size;
      st->stream_channels = packet_stream_channels;
      ret = opus_decode_frame(st, data, size[0], pcm+st->channels*(frame_size-packet_frame_size),
            packet_frame_size, 1);
      if (ret<0)
         return ret;
      else {
         if (OPUS_CHECK_ARRAY(pcm, frame_size*st->channels))
            OPUS_PRINT_INT(frame_size);
         st->last_packet_duration = frame_size;
         return frame_size;
      }
   }

   if (count*packet_frame_size > frame_size)
      return OPUS_BUFFER_TOO_SMALL;

   /* Update the state as the last step to avoid updating it on an invalid packet */
   st->mode = packet_mode;
   st->bandwidth = packet_bandwidth;
   st->frame_size = packet_frame_size;
   st->stream_channels = packet_stream_channels;

   nb_samples=0;
   for (i=0;i<count;i++)
   {
      int ret;
      ret = opus_decode_frame(st, data, size[i], pcm+nb_samples*st->channels, frame_size-nb_samples, 0);
      if (ret<0)
         return ret;
      celt_assert(ret==packet_frame_size);
      data += size[i];
      nb_samples += ret;
   }
   st->last_packet_duration = nb_samples;
   if (OPUS_CHECK_ARRAY(pcm, nb_samples*st->channels))
      OPUS_PRINT_INT(nb_samples);
#ifndef FIXED_POINT
   if (soft_clip)
      opus_pcm_soft_clip(pcm, nb_samples, st->channels, st->softclip_mem);
   else
      st->softclip_mem[0]=st->softclip_mem[1]=0;
#endif
   return nb_samples;
}

#ifdef FIXED_POINT

int opus_decode(OpusDecoder *st, const unsigned char *data,
      opus_int32 len, opus_val16 *pcm, int frame_size, int decode_fec)
{
   if(frame_size<=0)
      return OPUS_BAD_ARG;
   return opus_decode_native(st, data, len, pcm, frame_size, decode_fec, 0, NULL, 0);
}

#ifndef DISABLE_FLOAT_API
int opus_decode_float(OpusDecoder *st, const unsigned char *data,
      opus_int32 len, float *pcm, int frame_size, int decode_fec)
{
   VARDECL(opus_int16, out);
   int ret, i;
   int nb_samples;
   ALLOC_STACK;

   if(frame_size<=0)
   {
      RESTORE_STACK;
      return OPUS_BAD_ARG;
   }
   if (data != NULL && len > 0 && !decode_fec)
   {
      nb_samples = opus_decoder_get_nb_samples(st, data, len);
      if (nb_samples>0)
         frame_size = IMIN(frame_size, nb_samples);
      else
         return OPUS_INVALID_PACKET;
   }
   celt_assert(st->channels == 1 || st->channels == 2);
   ALLOC(out, frame_size*st->channels, opus_int16);

   ret = opus_decode_native(st, data, len, out, frame_size, decode_fec, 0, NULL, 0);
   if (ret > 0)
   {
      for (i=0;i<ret*st->channels;i++)
         pcm[i] = (1.f/32768.f)*(out[i]);
   }
   RESTORE_STACK;
   return ret;
}
#endif


#else
int opus_decode(OpusDecoder *st, const unsigned char *data,
      opus_int32 len, opus_int16 *pcm, int frame_size, int decode_fec)
{
   VARDECL(float, out);
   int ret, i;
   int nb_samples;
   ALLOC_STACK;

   if(frame_size<=0)
   {
      RESTORE_STACK;
      return OPUS_BAD_ARG;
   }

   if (data != NULL && len > 0 && !decode_fec)
   {
      nb_samples = opus_decoder_get_nb_samples(st, data, len);
      if (nb_samples>0)
         frame_size = IMIN(frame_size, nb_samples);
      else
         return OPUS_INVALID_PACKET;
   }
   celt_assert(st->channels == 1 || st->channels == 2);
   ALLOC(out, frame_size*st->channels, float);

   ret = opus_decode_native(st, data, len, out, frame_size, decode_fec, 0, NULL, 1);
   if (ret > 0)
   {
      for (i=0;i<ret*st->channels;i++)
         pcm[i] = FLOAT2INT16(out[i]);
   }
   RESTORE_STACK;
   return ret;
}

int opus_decode_float(OpusDecoder *st, const unsigned char *data,
      opus_int32 len, opus_val16 *pcm, int frame_size, int decode_fec)
{
   if(frame_size<=0)
      return OPUS_BAD_ARG;
   return opus_decode_native(st, data, len, pcm, frame_size, decode_fec, 0, NULL, 0);
}

#endif

int opus_decoder_ctl(OpusDecoder *st, int request, ...)
{
   int ret = OPUS_OK;
   va_list ap;
   void *silk_dec;
   CELTDecoder *celt_dec;

   silk_dec = (char*)st+st->silk_dec_offset;
   celt_dec = (CELTDecoder*)((char*)st+st->celt_dec_offset);


   va_start(ap, request);

   switch (request)
   {
   case OPUS_GET_BANDWIDTH_REQUEST:
   {
      opus_int32 *value = va_arg(ap, opus_int32*);
      if (!value)
      {
         goto bad_arg;
      }
      *value = st->bandwidth;
   }
   break;
   case OPUS_GET_FINAL_RANGE_REQUEST:
   {
      opus_uint32 *value = va_arg(ap, opus_uint32*);
      if (!value)
      {
         goto bad_arg;
      }
      *value = st->rangeFinal;
   }
   break;
   case OPUS_RESET_STATE:
   {
      OPUS_CLEAR((char*)&st->OPUS_DECODER_RESET_START,
            sizeof(OpusDecoder)-
            ((char*)&st->OPUS_DECODER_RESET_START - (char*)st));

      celt_decoder_ctl(celt_dec, OPUS_RESET_STATE);
      silk_InitDecoder( silk_dec );
      st->stream_channels = st->channels;
      st->frame_size = st->Fs/400;
   }
   break;
   case OPUS_GET_SAMPLE_RATE_REQUEST:
   {
      opus_int32 *value = va_arg(ap, opus_int32*);
      if (!value)
      {
         goto bad_arg;
      }
      *value = st->Fs;
   }
   break;
   case OPUS_GET_PITCH_REQUEST:
   {
      opus_int32 *value = va_arg(ap, opus_int32*);
      if (!value)
      {
         goto bad_arg;
      }
      if (st->prev_mode == MODE_CELT_ONLY)
         ret = celt_decoder_ctl(celt_dec, OPUS_GET_PITCH(value));
      else
         *value = st->DecControl.prevPitchLag;
   }
   break;
   case OPUS_GET_GAIN_REQUEST:
   {
      opus_int32 *value = va_arg(ap, opus_int32*);
      if (!value)
      {
         goto bad_arg;
      }
      *value = st->decode_gain;
   }
   break;
   case OPUS_SET_GAIN_REQUEST:
   {
       opus_int32 value = va_arg(ap, opus_int32);
       if (value<-32768 || value>32767)
       {
          goto bad_arg;
       }
       st->decode_gain = value;
   }
   break;
   case OPUS_GET_LAST_PACKET_DURATION_REQUEST:
   {
      opus_int32 *value = va_arg(ap, opus_int32*);
      if (!value)
      {
         goto bad_arg;
      }
      *value = st->last_packet_duration;
   }
   break;
   case OPUS_SET_PHASE_INVERSION_DISABLED_REQUEST:
   {
       opus_int32 value = va_arg(ap, opus_int32);
       if(value<0 || value>1)
       {
          goto bad_arg;
       }
       ret = celt_decoder_ctl(celt_dec, OPUS_SET_PHASE_INVERSION_DISABLED(value));
   }
   break;
   case OPUS_GET_PHASE_INVERSION_DISABLED_REQUEST:
   {
       opus_int32 *value = va_arg(ap, opus_int32*);
       if (!value)
       {
          goto bad_arg;
       }
       ret = celt_decoder_ctl(celt_dec, OPUS_GET_PHASE_INVERSION_DISABLED(value));
   }
   break;
   default:
      /*fprintf(stderr, "unknown opus_decoder_ctl() request: %d", request);*/
      ret = OPUS_UNIMPLEMENTED;
      break;
   }

   va_end(ap);
   return ret;
bad_arg:
   va_end(ap);
   return OPUS_BAD_ARG;
}

void opus_decoder_destroy(OpusDecoder *st)
{
   opus_free(st);
}


int opus_packet_get_bandwidth(const unsigned char *data)
{
   int bandwidth;
   if (data[0]&0x80)
   {
      bandwidth = OPUS_BANDWIDTH_MEDIUMBAND + ((data[0]>>5)&0x3);
      if (bandwidth == OPUS_BANDWIDTH_MEDIUMBAND)
         bandwidth = OPUS_BANDWIDTH_NARROWBAND;
   } else if ((data[0]&0x60) == 0x60)
   {
      bandwidth = (data[0]&0x10) ? OPUS_BANDWIDTH_FULLBAND :
                                   OPUS_BANDWIDTH_SUPERWIDEBAND;
   } else {
      bandwidth = OPUS_BANDWIDTH_NARROWBAND + ((data[0]>>5)&0x3);
   }
   return bandwidth;
}

int opus_packet_get_nb_channels(const unsigned char *data)
{
   return (data[0]&0x4) ? 2 : 1;
}

int opus_packet_get_nb_frames(const unsigned char packet[], opus_int32 len)
{
   int count;
   if (len<1)
      return OPUS_BAD_ARG;
   count = packet[0]&0x3;
   if (count==0)
      return 1;
   else if (count!=3)
      return 2;
   else if (len<2)
      return OPUS_INVALID_PACKET;
   else
      return packet[1]&0x3F;
}

int opus_packet_get_nb_samples(const unsigned char packet[], opus_int32 len,
      opus_int32 Fs)
{
   int samples;
   int count = opus_packet_get_nb_frames(packet, len);

   if (count<0)
      return count;

   samples = count*opus_packet_get_samples_per_frame(packet, Fs);
   /* Can't have more than 120 ms */
   if (samples*25 > Fs*3)
      return OPUS_INVALID_PACKET;
   else
      return samples;
}

int opus_decoder_get_nb_samples(const OpusDecoder *dec,
      const unsigned char packet[], opus_int32 len)
{
   return opus_packet_get_nb_samples(packet, len, dec->Fs);
}