summaryrefslogtreecommitdiffstats
path: root/libavcodec/dss_sp.c
blob: 14025fcddee1b6068f1c0ac46917fecd5a846117 (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
/*
 * Digital Speech Standard - Standard Play mode (DSS SP) audio decoder.
 * Copyright (C) 2014 Oleksij Rempel <linux@rempel-privat.de>
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include "libavutil/channel_layout.h"
#include "libavutil/common.h"
#include "libavutil/mem.h"
#include "libavutil/opt.h"

#include "avcodec.h"
#include "get_bits.h"
#include "internal.h"

#define SUBFRAMES 4
#define PULSE_MAX 8

#define DSS_SP_FRAME_SIZE        42
#define DSS_SP_SAMPLE_COUNT     (66 * SUBFRAMES)
#define DSS_SP_FORMULA(a, b, c) ((int)((((a) * (1 << 15)) + (b) * (unsigned)(c)) + 0x4000) >> 15)

typedef struct DssSpSubframe {
    int16_t gain;
    int32_t combined_pulse_pos;
    int16_t pulse_pos[7];
    int16_t pulse_val[7];
} DssSpSubframe;

typedef struct DssSpFrame {
    int16_t filter_idx[14];
    int16_t sf_adaptive_gain[SUBFRAMES];
    int16_t pitch_lag[SUBFRAMES];
    struct DssSpSubframe sf[SUBFRAMES];
} DssSpFrame;

typedef struct DssSpContext {
    AVCodecContext *avctx;
    int32_t excitation[288 + 6];
    int32_t history[187];
    DssSpFrame fparam;
    int32_t working_buffer[SUBFRAMES][72];
    int32_t audio_buf[15];
    int32_t err_buf1[15];
    int32_t lpc_filter[14];
    int32_t filter[15];
    int32_t vector_buf[72];
    int noise_state;
    int32_t err_buf2[15];

    int pulse_dec_mode;

    DECLARE_ALIGNED(16, uint8_t, bits)[DSS_SP_FRAME_SIZE +
                                       AV_INPUT_BUFFER_PADDING_SIZE];
} DssSpContext;

/*
 * Used for the coding/decoding of the pulse positions for the MP-MLQ codebook.
 */
static const uint32_t dss_sp_combinatorial_table[PULSE_MAX][72] = {
    {       0,         0,         0,          0,          0,          0,
            0,         0,         0,          0,          0,          0,
            0,         0,         0,          0,          0,          0,
            0,         0,         0,          0,          0,          0,
            0,         0,         0,          0,          0,          0,
            0,         0,         0,          0,          0,          0,
            0,         0,         0,          0,          0,          0,
            0,         0,         0,          0,          0,          0,
            0,         0,         0,          0,          0,          0,
            0,         0,         0,          0,          0,          0,
            0,         0,         0,          0,          0,          0,
            0,         0,         0,          0,          0,          0 },
    {       0,         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 },
    {       0,         0,         1,          3,          6,         10,
           15,        21,        28,         36,         45,         55,
           66,        78,        91,        105,        120,        136,
          153,       171,       190,        210,        231,        253,
          276,       300,       325,        351,        378,        406,
          435,       465,       496,        528,        561,        595,
          630,       666,       703,        741,        780,        820,
          861,       903,       946,        990,       1035,       1081,
         1128,      1176,      1225,       1275,       1326,       1378,
         1431,      1485,      1540,       1596,       1653,       1711,
         1770,      1830,      1891,       1953,       2016,       2080,
         2145,      2211,      2278,       2346,       2415,       2485 },
    {       0,         0,         0,          1,          4,         10,
           20,        35,        56,         84,        120,        165,
          220,       286,       364,        455,        560,        680,
          816,       969,      1140,       1330,       1540,       1771,
         2024,      2300,      2600,       2925,       3276,       3654,
         4060,      4495,      4960,       5456,       5984,       6545,
         7140,      7770,      8436,       9139,       9880,      10660,
        11480,     12341,     13244,      14190,      15180,      16215,
        17296,     18424,     19600,      20825,      22100,      23426,
        24804,     26235,     27720,      29260,      30856,      32509,
        34220,     35990,     37820,      39711,      41664,      43680,
        45760,     47905,     50116,      52394,      54740,      57155 },
    {       0,         0,         0,          0,          1,          5,
           15,        35,        70,        126,        210,        330,
          495,       715,      1001,       1365,       1820,       2380,
         3060,      3876,      4845,       5985,       7315,       8855,
        10626,     12650,     14950,      17550,      20475,      23751,
        27405,     31465,     35960,      40920,      46376,      52360,
        58905,     66045,     73815,      82251,      91390,     101270,
       111930,    123410,    135751,     148995,     163185,     178365,
       194580,    211876,    230300,     249900,     270725,     292825,
       316251,    341055,    367290,     395010,     424270,     455126,
       487635,    521855,    557845,     595665,     635376,     677040,
       720720,    766480,    814385,     864501,     916895,     971635 },
    {       0,         0,         0,          0,          0,          1,
            6,        21,        56,        126,        252,        462,
          792,      1287,      2002,       3003,       4368,       6188,
         8568,     11628,     15504,      20349,      26334,      33649,
        42504,     53130,     65780,      80730,      98280,     118755,
       142506,    169911,    201376,     237336,     278256,     324632,
       376992,    435897,    501942,     575757,     658008,     749398,
       850668,    962598,   1086008,    1221759,    1370754,    1533939,
      1712304,   1906884,   2118760,    2349060,    2598960,    2869685,
      3162510,   3478761,   3819816,    4187106,    4582116,    5006386,
      5461512,   5949147,   6471002,    7028847,    7624512,    8259888,
      8936928,   9657648,  10424128,   11238513,   12103014,   13019909 },
    {       0,         0,         0,          0,          0,          0,
            1,         7,        28,         84,        210,        462,
          924,      1716,      3003,       5005,       8008,      12376,
        18564,     27132,     38760,      54264,      74613,     100947,
       134596,    177100,    230230,     296010,     376740,     475020,
       593775,    736281,    906192,    1107568,    1344904,    1623160,
      1947792,   2324784,   2760681,    3262623,    3838380,    4496388,
      5245786,   6096454,   7059052,    8145060,    9366819,   10737573,
     12271512,  13983816,  15890700,   18009460,   20358520,   22957480,
     25827165,  28989675,  32468436,   36288252,   40475358,   45057474,
     50063860,  55525372,  61474519,   67945521,   74974368,   82598880,
     90858768,  99795696, 109453344,  119877472,  131115985,  143218999 },
    {       0,         0,         0,          0,          0,          0,
            0,         1,         8,         36,        120,        330,
          792,      1716,      3432,       6435,      11440,      19448,
        31824,     50388,     77520,     116280,     170544,     245157,
       346104,    480700,    657800,     888030,    1184040,    1560780,
      2035800,   2629575,   3365856,    4272048,    5379616,    6724520,
      8347680,  10295472,  12620256,   15380937,   18643560,   22481940,
     26978328,  32224114,  38320568,   45379620,   53524680,   62891499,
     73629072,  85900584,  99884400,  115775100,  133784560,  154143080,
    177100560, 202927725, 231917400,  264385836,  300674088,  341149446,
    386206920, 436270780, 491796152,  553270671,  621216192,  696190560,
    778789440, 869648208, 969443904, 1078897248, 1198774720, 1329890705 },
};

static const int16_t dss_sp_filter_cb[14][32] = {
    { -32653, -32587, -32515, -32438, -32341, -32216, -32062, -31881,
      -31665, -31398, -31080, -30724, -30299, -29813, -29248, -28572,
      -27674, -26439, -24666, -22466, -19433, -16133, -12218,  -7783,
       -2834,   1819,   6544,  11260,  16050,  20220,  24774,  28120 },

    { -27503, -24509, -20644, -17496, -14187, -11277,  -8420,  -5595,
       -3013,   -624,   1711,   3880,   5844,   7774,   9739,  11592,
       13364,  14903,  16426,  17900,  19250,  20586,  21803,  23006,
       24142,  25249,  26275,  27300,  28359,  29249,  30118,  31183 },

    { -27827, -24208, -20943, -17781, -14843, -11848,  -9066,  -6297,
       -3660,   -910,   1918,   5025,   8223,  11649,  15086,  18423,
           0,      0,      0,      0,      0,      0,      0,      0,
           0,      0,      0,      0,      0,      0,      0,      0 },

    { -17128, -11975,  -8270,  -5123,  -2296,    183,   2503,   4707,
        6798,   8945,  11045,  13239,  15528,  18248,  21115,  24785,
           0,      0,      0,      0,      0,      0,      0,      0,
           0,      0,      0,      0,      0,      0,      0,      0 },

    { -21557, -17280, -14286, -11644,  -9268,  -7087,  -4939,  -2831,
        -691,   1407,   3536,   5721,   8125,  10677,  13721,  17731,
           0,      0,      0,      0,      0,      0,      0,      0,
           0,      0,      0,      0,      0,      0,      0,      0 },

    { -15030, -10377,  -7034,  -4327,  -1900,    364,   2458,   4450,
        6422,   8374,  10374,  12486,  14714,  16997,  19626,  22954,
           0,      0,      0,      0,      0,      0,      0,      0,
           0,      0,      0,      0,      0,      0,      0,      0 },

    { -16155, -12362,  -9698,  -7460,  -5258,  -3359,  -1547,    219,
        1916,   3599,   5299,   6994,   8963,  11226,  13716,  16982,
           0,      0,      0,      0,      0,      0,      0,      0,
           0,      0,      0,      0,      0,      0,      0,      0 },

    { -14742,  -9848,  -6921,  -4648,  -2769,  -1065,    499,   2083,
        3633,   5219,   6857,   8580,  10410,  12672,  15561,  20101,
           0,      0,      0,      0,      0,      0,      0,      0,
           0,      0,      0,      0,      0,      0,      0,      0 },

    { -11099,  -7014,  -3855,  -1025,   1680,   4544,   7807,  11932,
           0,      0,      0,      0,      0,      0,      0,      0,
           0,      0,      0,      0,      0,      0,      0,      0,
           0,      0,      0,      0,      0,      0,      0,      0 },

    {  -9060,  -4570,  -1381,   1419,   4034,   6728,   9865,  14149,
           0,      0,      0,      0,      0,      0,      0,      0,
           0,      0,      0,      0,      0,      0,      0,      0,
           0,      0,      0,      0,      0,      0,      0,      0 },

    { -12450,  -7985,  -4596,  -1734,    961,   3629,   6865,  11142,
           0,      0,      0,      0,      0,      0,      0,      0,
           0,      0,      0,      0,      0,      0,      0,      0,
           0,      0,      0,      0,      0,      0,      0,      0 },

    { -11831,  -7404,  -4010,  -1096,   1606,   4291,   7386,  11482,
           0,      0,      0,      0,      0,      0,      0,      0,
           0,      0,      0,      0,      0,      0,      0,      0,
           0,      0,      0,      0,      0,      0,      0,      0 },

    { -13404,  -9250,  -5995,  -3312,   -890,   1594,   4464,   8198,
           0,      0,      0,      0,      0,      0,      0,      0,
           0,      0,      0,      0,      0,      0,      0,      0,
           0,      0,      0,      0,      0,      0,      0,      0 },

    { -11239,  -7220,  -4040,  -1406,    971,   3321,   6006,   9697,
           0,      0,      0,      0,      0,      0,      0,      0,
           0,      0,      0,      0,      0,      0,      0,      0,
           0,      0,      0,      0,      0,      0,      0,      0 },
};

static const uint16_t  dss_sp_fixed_cb_gain[64] = {
       0,    4,    8,   13,   17,   22,   26,   31,
      35,   40,   44,   48,   53,   58,   63,   69,
      76,   83,   91,   99,  109,  119,  130,  142,
     155,  170,  185,  203,  222,  242,  265,  290,
     317,  346,  378,  414,  452,  494,  540,  591,
     646,  706,  771,  843,  922, 1007, 1101, 1204,
    1316, 1438, 1572, 1719, 1879, 2053, 2244, 2453,
    2682, 2931, 3204, 3502, 3828, 4184, 4574, 5000,
};

static const int16_t  dss_sp_pulse_val[8] = {
    -31182, -22273, -13364, -4455, 4455, 13364, 22273, 31182
};

static const uint16_t binary_decreasing_array[] = {
    32767, 16384, 8192, 4096, 2048, 1024, 512, 256,
    128, 64, 32, 16, 8, 4, 2,
};

static const uint16_t dss_sp_unc_decreasing_array[] = {
    32767, 26214, 20972, 16777, 13422, 10737, 8590, 6872,
    5498, 4398, 3518, 2815, 2252, 1801, 1441,
};

static const uint16_t dss_sp_adaptive_gain[] = {
     102,  231,  360,  488,  617,  746,  875, 1004,
    1133, 1261, 1390, 1519, 1648, 1777, 1905, 2034,
    2163, 2292, 2421, 2550, 2678, 2807, 2936, 3065,
    3194, 3323, 3451, 3580, 3709, 3838, 3967, 4096,
};

static const int32_t dss_sp_sinc[67] = {
      262,   293,   323,   348,   356,   336,   269,   139,
      -67,  -358,  -733, -1178, -1668, -2162, -2607, -2940,
    -3090, -2986, -2562, -1760,  -541,  1110,  3187,  5651,
     8435, 11446, 14568, 17670, 20611, 23251, 25460, 27125,
    28160, 28512, 28160,
    27125, 25460, 23251, 20611, 17670, 14568, 11446,  8435,
     5651,  3187,  1110,  -541, -1760, -2562, -2986, -3090,
    -2940, -2607, -2162, -1668, -1178,  -733,  -358,   -67,
      139,   269,   336,   356,   348,   323,   293,   262,
};

static av_cold int dss_sp_decode_init(AVCodecContext *avctx)
{
    DssSpContext *p = avctx->priv_data;
    avctx->channel_layout = AV_CH_LAYOUT_MONO;
    avctx->sample_fmt     = AV_SAMPLE_FMT_S16;
    avctx->channels       = 1;
    avctx->sample_rate    = 11025;

    memset(p->history, 0, sizeof(p->history));
    p->pulse_dec_mode = 1;
    p->avctx          = avctx;

    return 0;
}

static void dss_sp_unpack_coeffs(DssSpContext *p, const uint8_t *src)
{
    GetBitContext gb;
    DssSpFrame *fparam = &p->fparam;
    int i;
    int subframe_idx;
    uint32_t combined_pitch;
    uint32_t tmp;
    uint32_t pitch_lag;

    for (i = 0; i < DSS_SP_FRAME_SIZE; i += 2) {
        p->bits[i]     = src[i + 1];
        p->bits[i + 1] = src[i];
    }

    init_get_bits(&gb, p->bits, DSS_SP_FRAME_SIZE * 8);

    for (i = 0; i < 2; i++)
        fparam->filter_idx[i] = get_bits(&gb, 5);
    for (; i < 8; i++)
        fparam->filter_idx[i] = get_bits(&gb, 4);
    for (; i < 14; i++)
        fparam->filter_idx[i] = get_bits(&gb, 3);

    for (subframe_idx = 0; subframe_idx < 4; subframe_idx++) {
        fparam->sf_adaptive_gain[subframe_idx] = get_bits(&gb, 5);

        fparam->sf[subframe_idx].combined_pulse_pos = get_bits_long(&gb, 31);

        fparam->sf[subframe_idx].gain = get_bits(&gb, 6);

        for (i = 0; i < 7; i++)
            fparam->sf[subframe_idx].pulse_val[i] = get_bits(&gb, 3);
    }

    for (subframe_idx = 0; subframe_idx < 4; subframe_idx++) {
        unsigned int C72_binomials[PULSE_MAX] = {
            72, 2556, 59640, 1028790, 13991544, 156238908, 1473109704,
            3379081753
        };
        unsigned int combined_pulse_pos =
            fparam->sf[subframe_idx].combined_pulse_pos;
        int index = 6;

        if (combined_pulse_pos < C72_binomials[PULSE_MAX - 1]) {
            if (p->pulse_dec_mode) {
                int pulse, pulse_idx;
                pulse              = PULSE_MAX - 1;
                pulse_idx          = 71;
                combined_pulse_pos =
                    fparam->sf[subframe_idx].combined_pulse_pos;

                /* this part seems to be close to g723.1 gen_fcb_excitation()
                 * RATE_6300 */

                /* TODO: what is 7? size of subframe? */
                for (i = 0; i < 7; i++) {
                    for (;
                         combined_pulse_pos <
                         dss_sp_combinatorial_table[pulse][pulse_idx];
                         --pulse_idx)
                        ;
                    combined_pulse_pos -=
                        dss_sp_combinatorial_table[pulse][pulse_idx];
                    pulse--;
                    fparam->sf[subframe_idx].pulse_pos[i] = pulse_idx;
                }
            }
        } else {
            p->pulse_dec_mode = 0;

            /* why do we need this? */
            fparam->sf[subframe_idx].pulse_pos[6] = 0;

            for (i = 71; i >= 0; i--) {
                if (C72_binomials[index] <= combined_pulse_pos) {
                    combined_pulse_pos -= C72_binomials[index];

                    fparam->sf[subframe_idx].pulse_pos[6 - index] = i;

                    if (!index)
                        break;
                    --index;
                }
                --C72_binomials[0];
                if (index) {
                    int a;
                    for (a = 0; a < index; a++)
                        C72_binomials[a + 1] -= C72_binomials[a];
                }
            }
        }
    }

    combined_pitch = get_bits(&gb, 24);

    fparam->pitch_lag[0] = (combined_pitch % 151) + 36;

    combined_pitch /= 151;

    for (i = 1; i < SUBFRAMES - 1; i++) {
        fparam->pitch_lag[i] = combined_pitch % 48;
        combined_pitch      /= 48;
    }
    if (combined_pitch > 47) {
        av_log (p->avctx, AV_LOG_WARNING, "combined_pitch was too large\n");
        combined_pitch = 0;
    }
    fparam->pitch_lag[i] = combined_pitch;

    pitch_lag = fparam->pitch_lag[0];
    for (i = 1; i < SUBFRAMES; i++) {
        if (pitch_lag > 162) {
            fparam->pitch_lag[i] += 162 - 23;
        } else {
            tmp = pitch_lag - 23;
            if (tmp < 36)
                tmp = 36;
            fparam->pitch_lag[i] += tmp;
        }
        pitch_lag = fparam->pitch_lag[i];
    }
}

static void dss_sp_unpack_filter(DssSpContext *p)
{
    int i;

    for (i = 0; i < 14; i++)
        p->lpc_filter[i] = dss_sp_filter_cb[i][p->fparam.filter_idx[i]];
}

static void dss_sp_convert_coeffs(int32_t *lpc_filter, int32_t *coeffs)
{
    int a, a_plus, i;

    coeffs[0] = 0x2000;
    for (a = 0; a < 14; a++) {
        a_plus         = a + 1;
        coeffs[a_plus] = lpc_filter[a] >> 2;
        if (a_plus / 2 >= 1) {
            for (i = 1; i <= a_plus / 2; i++) {
                int coeff_1, coeff_2, tmp;

                coeff_1 = coeffs[i];
                coeff_2 = coeffs[a_plus - i];

                tmp = DSS_SP_FORMULA(coeff_1, lpc_filter[a], coeff_2);
                coeffs[i] = av_clip_int16(tmp);

                tmp = DSS_SP_FORMULA(coeff_2, lpc_filter[a], coeff_1);
                coeffs[a_plus - i] = av_clip_int16(tmp);
            }
        }
    }
}

static void dss_sp_add_pulses(int32_t *vector_buf,
                              const struct DssSpSubframe *sf)
{
    int i;

    for (i = 0; i < 7; i++)
        vector_buf[sf->pulse_pos[i]] += (dss_sp_fixed_cb_gain[sf->gain] *
                                         dss_sp_pulse_val[sf->pulse_val[i]] +
                                         0x4000) >> 15;
}

static void dss_sp_gen_exc(int32_t *vector, int32_t *prev_exc,
                           int pitch_lag, int gain)
{
    int i;

    /* do we actually need this check? we can use just [a3 - i % a3]
     * for both cases */
    if (pitch_lag < 72)
        for (i = 0; i < 72; i++)
            vector[i] = prev_exc[pitch_lag - i % pitch_lag];
    else
        for (i = 0; i < 72; i++)
            vector[i] = prev_exc[pitch_lag - i];

    for (i = 0; i < 72; i++) {
        int tmp = gain * vector[i] >> 11;
        vector[i] = av_clip_int16(tmp);
    }
}

static void dss_sp_scale_vector(int32_t *vec, int bits, int size)
{
    int i;

    if (bits < 0)
        for (i = 0; i < size; i++)
            vec[i] = vec[i] >> -bits;
    else
        for (i = 0; i < size; i++)
            vec[i] = vec[i] * (1 << bits);
}

static void dss_sp_update_buf(int32_t *hist, int32_t *vector)
{
    int i;

    for (i = 114; i > 0; i--)
        vector[i + 72] = vector[i];

    for (i = 0; i < 72; i++)
        vector[72 - i] = hist[i];
}

static void dss_sp_shift_sq_sub(const int32_t *filter_buf,
                                int32_t *error_buf, int32_t *dst)
{
    int a;

    for (a = 0; a < 72; a++) {
        int i, tmp;

        tmp = dst[a] * filter_buf[0];

        for (i = 14; i > 0; i--)
            tmp -= error_buf[i] * (unsigned)filter_buf[i];

        for (i = 14; i > 0; i--)
            error_buf[i] = error_buf[i - 1];

        tmp = (int)(tmp + 4096U) >> 13;

        error_buf[1] = tmp;

        dst[a] = av_clip_int16(tmp);
    }
}

static void dss_sp_shift_sq_add(const int32_t *filter_buf, int32_t *audio_buf,
                                int32_t *dst)
{
    int a;

    for (a = 0; a < 72; a++) {
        int i, tmp = 0;

        audio_buf[0] = dst[a];

        for (i = 14; i >= 0; i--)
            tmp += audio_buf[i] * filter_buf[i];

        for (i = 14; i > 0; i--)
            audio_buf[i] = audio_buf[i - 1];

        tmp = (tmp + 4096) >> 13;

        dst[a] = av_clip_int16(tmp);
    }
}

static void dss_sp_vec_mult(const int32_t *src, int32_t *dst,
                            const int16_t *mult)
{
    int i;

    dst[0] = src[0];

    for (i = 1; i < 15; i++)
        dst[i] = (src[i] * mult[i] + 0x4000) >> 15;
}

static int dss_sp_get_normalize_bits(int32_t *vector_buf, int16_t size)
{
    unsigned int val;
    int max_val;
    int i;

    val = 1;
    for (i = 0; i < size; i++)
        val |= FFABS(vector_buf[i]);

    for (max_val = 0; val <= 0x4000; ++max_val)
        val *= 2;
    return max_val;
}

static int dss_sp_vector_sum(DssSpContext *p, int size)
{
    int i, sum = 0;
    for (i = 0; i < size; i++)
        sum += FFABS(p->vector_buf[i]);
    return sum;
}

static void dss_sp_sf_synthesis(DssSpContext *p, int32_t lpc_filter,
                                int32_t *dst, int size)
{
    int32_t tmp_buf[15];
    int32_t noise[72];
    int bias, vsum_2 = 0, vsum_1 = 0, v36, normalize_bits;
    int i, tmp;

    if (size > 0) {
        vsum_1 = dss_sp_vector_sum(p, size);

        if (vsum_1 > 0xFFFFF)
            vsum_1 = 0xFFFFF;
    }

    normalize_bits = dss_sp_get_normalize_bits(p->vector_buf, size);

    dss_sp_scale_vector(p->vector_buf, normalize_bits - 3, size);
    dss_sp_scale_vector(p->audio_buf, normalize_bits, 15);
    dss_sp_scale_vector(p->err_buf1, normalize_bits, 15);

    v36 = p->err_buf1[1];

    dss_sp_vec_mult(p->filter, tmp_buf, binary_decreasing_array);
    dss_sp_shift_sq_add(tmp_buf, p->audio_buf, p->vector_buf);

    dss_sp_vec_mult(p->filter, tmp_buf, dss_sp_unc_decreasing_array);
    dss_sp_shift_sq_sub(tmp_buf, p->err_buf1, p->vector_buf);

    /* lpc_filter can be negative */
    lpc_filter = lpc_filter >> 1;
    if (lpc_filter >= 0)
        lpc_filter = 0;

    if (size > 1) {
        for (i = size - 1; i > 0; i--) {
            tmp = DSS_SP_FORMULA(p->vector_buf[i], lpc_filter,
                                 p->vector_buf[i - 1]);
            p->vector_buf[i] = av_clip_int16(tmp);
        }
    }

    tmp              = DSS_SP_FORMULA(p->vector_buf[0], lpc_filter, v36);
    p->vector_buf[0] = av_clip_int16(tmp);

    dss_sp_scale_vector(p->vector_buf, -normalize_bits, size);
    dss_sp_scale_vector(p->audio_buf, -normalize_bits, 15);
    dss_sp_scale_vector(p->err_buf1, -normalize_bits, 15);

    if (size > 0)
        vsum_2 = dss_sp_vector_sum(p, size);

    if (vsum_2 >= 0x40)
        tmp = (vsum_1 << 11) / vsum_2;
    else
        tmp = 1;

    bias     = 409 * tmp >> 15 << 15;
    tmp      = (bias + 32358 * p->noise_state) >> 15;
    noise[0] = av_clip_int16(tmp);

    for (i = 1; i < size; i++) {
        tmp      = (bias + 32358 * noise[i - 1]) >> 15;
        noise[i] = av_clip_int16(tmp);
    }

    p->noise_state = noise[size - 1];
    for (i = 0; i < size; i++) {
        tmp    = (p->vector_buf[i] * noise[i]) >> 11;
        dst[i] = av_clip_int16(tmp);
    }
}

static void dss_sp_update_state(DssSpContext *p, int32_t *dst)
{
    int i, offset = 6, counter = 0, a = 0;

    for (i = 0; i < 6; i++)
        p->excitation[i] = p->excitation[288 + i];

    for (i = 0; i < 72 * SUBFRAMES; i++)
        p->excitation[6 + i] = dst[i];

    do {
        int tmp = 0;

        for (i = 0; i < 6; i++)
            tmp += p->excitation[offset--] * dss_sp_sinc[a + i * 11];

        offset += 7;

        tmp >>= 15;
        dst[counter] = av_clip_int16(tmp);

        counter++;

        a = (a + 1) % 11;
        if (!a)
            offset++;
    } while (offset < FF_ARRAY_ELEMS(p->excitation));
}

static void dss_sp_32to16bit(int16_t *dst, int32_t *src, int size)
{
    int i;

    for (i = 0; i < size; i++)
        dst[i] = av_clip_int16(src[i]);
}

static int dss_sp_decode_one_frame(DssSpContext *p,
                                   int16_t *abuf_dst, const uint8_t *abuf_src)
{
    int i, j;

    dss_sp_unpack_coeffs(p, abuf_src);

    dss_sp_unpack_filter(p);

    dss_sp_convert_coeffs(p->lpc_filter, p->filter);

    for (j = 0; j < SUBFRAMES; j++) {
        dss_sp_gen_exc(p->vector_buf, p->history,
                       p->fparam.pitch_lag[j],
                       dss_sp_adaptive_gain[p->fparam.sf_adaptive_gain[j]]);

        dss_sp_add_pulses(p->vector_buf, &p->fparam.sf[j]);

        dss_sp_update_buf(p->vector_buf, p->history);

        for (i = 0; i < 72; i++)
            p->vector_buf[i] = p->history[72 - i];

        dss_sp_shift_sq_sub(p->filter,
                            p->err_buf2, p->vector_buf);

        dss_sp_sf_synthesis(p, p->lpc_filter[0],
                            &p->working_buffer[j][0], 72);
    }

    dss_sp_update_state(p, &p->working_buffer[0][0]);

    dss_sp_32to16bit(abuf_dst,
                     &p->working_buffer[0][0], 264);
    return 0;
}

static int dss_sp_decode_frame(AVCodecContext *avctx, void *data,
                               int *got_frame_ptr, AVPacket *avpkt)
{
    DssSpContext *p    = avctx->priv_data;
    AVFrame *frame     = data;
    const uint8_t *buf = avpkt->data;
    int buf_size       = avpkt->size;

    int16_t *out;
    int ret;

    if (buf_size < DSS_SP_FRAME_SIZE) {
        if (buf_size)
            av_log(avctx, AV_LOG_WARNING,
                   "Expected %d bytes, got %d - skipping packet.\n",
                   DSS_SP_FRAME_SIZE, buf_size);
        *got_frame_ptr = 0;
        return AVERROR_INVALIDDATA;
    }

    frame->nb_samples = DSS_SP_SAMPLE_COUNT;
    if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
        return ret;

    out = (int16_t *)frame->data[0];

    dss_sp_decode_one_frame(p, out, buf);

    *got_frame_ptr = 1;

    return DSS_SP_FRAME_SIZE;
}

AVCodec ff_dss_sp_decoder = {
    .name           = "dss_sp",
    .long_name      = NULL_IF_CONFIG_SMALL("Digital Speech Standard - Standard Play mode (DSS SP)"),
    .type           = AVMEDIA_TYPE_AUDIO,
    .id             = AV_CODEC_ID_DSS_SP,
    .priv_data_size = sizeof(DssSpContext),
    .init           = dss_sp_decode_init,
    .decode         = dss_sp_decode_frame,
    .capabilities   = AV_CODEC_CAP_DR1,
};
OpenPOWER on IntegriCloud