dss_sp.c 28 KB
Newer Older
1 2 3 4
/*
 * Digital Speech Standard - Standard Play mode (DSS SP) audio decoder.
 * Copyright (C) 2014 Oleksij Rempel <linux@rempel-privat.de>
 *
5
 * This file is part of FFmpeg.
6
 *
7
 * FFmpeg is free software; you can redistribute it and/or
8 9 10 11
 * 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.
 *
12
 * FFmpeg is distributed in the hope that it will be useful,
13 14 15 16 17
 * 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
18
 * License along with FFmpeg; if not, write to the Free Software
19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35
 * 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)
36
#define DSS_SP_FORMULA(a, b, c) ((int)((((a) * (1 << 15)) + (b) * (unsigned)(c)) + 0x4000) >> 15)
37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52

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 {
53
    AVCodecContext *avctx;
54 55 56 57 58 59 60 61 62 63 64 65 66 67 68
    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 +
69
                                       AV_INPUT_BUFFER_PADDING_SIZE];
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
} 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;
300
    p->avctx          = avctx;
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

    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];

383
                    fparam->sf[subframe_idx].pulse_pos[6 - index] = i;
384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404

                    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;

405
    for (i = 1; i < SUBFRAMES - 1; i++) {
406 407 408
        fparam->pitch_lag[i] = combined_pitch % 48;
        combined_pitch      /= 48;
    }
409 410 411 412 413
    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;
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

    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++)
502
            vec[i] = vec[i] * (1 << bits);
503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526
}

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--)
527
            tmp -= error_buf[i] * (unsigned)filter_buf[i];
528 529 530 531

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

532
        tmp = (int)(tmp + 4096U) >> 13;
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

        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;
764
    if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
765 766 767 768 769 770 771 772 773 774 775 776
        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 = {
777
    .name           = "dss_sp",
778 779 780 781 782 783
    .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,
784
    .capabilities   = AV_CODEC_CAP_DR1,
785
};