aboutsummaryrefslogblamecommitdiffstats
path: root/libavcodec/dca_lbr.c
blob: 73bc16d275252429d1b3ab3899b49536dd1da2f4 (plain) (tree)
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738


















                                                                               

                                     
                                   




                          
                   

                      










































































                                                   









                                                            









                                                                         
 
                                         
 
          
                                         














                                                                        
                                   



















































                                                                        
                                   



































                                                             
            




                                           

                                                          






                                                            
                               
 
                                                             
 
                                                        
                 



















                                                                                
                                           
             
                                                                                          
                                                                                 
                                           





                                                                       
                                                             
                                                                                 
                                           


                                                  
                                                                                      








                                                                      
                                                                                                       































                                                                          
                       


                    


                                                          



                                                                                   
                                       





                                                                         



                                             




                                                               
            

                    

                                                          










                                                                   
                                   














                                                              
                                                                               






                                               
                                                                                       
                                                                              
                                       




                                    
                                                                               









































                                                                
                                                                                        











                                                                                  
                                   


                    

                                                          


                                                           






                                                                           





                                                                                   
                                                                                                    
                                             
                                                                                                            





                                                                       
                                   



























                                                                                        
                           


                                                           



                                                                 





                                               
                                                                                                        


















                                                                              
                                                                                                        












































































































                                                                                          
                                       



















                                                                          
                                       


























































                                                                                   
                                             


                    

                                                          































                                                                                   

                                       
                                                              

                                         


                                        
                                                                          
































                                                                                         
                                                                                                











                                                                               
            
                    








                                                                    



                                                                               
            
                    




                                                                     
                     


                                                           
     
                                                                                





                                                                          
            

                           

                                                               




































                                                                          
                               
















                                                                   
                         
                               
                                                           

                                                                    
                                                    

































































                                                                                                           
                                                



































































                                                                                                         
                                                                                







                                                  
                      













                                                                     
                                  



                                                                            
                                     

























































































































































































































































































































































































































































































































































                                                                                              
                                                     
 
                                            





                                            
                                            



                                                 
                                                                 
 






























































                                                                                        
                                               
                               













                                               
/*
 * Copyright (C) 2016 foo86
 *
 * 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
 */

#define BITSTREAM_READER_LE

#include "libavutil/channel_layout.h"
#include "libavutil/mem_internal.h"

#include "dcadec.h"
#include "dcadata.h"
#include "dcahuff.h"
#include "dca_syncwords.h"
#include "bytestream.h"
#include "decode.h"

#define AMP_MAX     56

enum LBRFlags {
    LBR_FLAG_24_BIT             = 0x01,
    LBR_FLAG_LFE_PRESENT        = 0x02,
    LBR_FLAG_BAND_LIMIT_2_3     = 0x04,
    LBR_FLAG_BAND_LIMIT_1_2     = 0x08,
    LBR_FLAG_BAND_LIMIT_1_3     = 0x0c,
    LBR_FLAG_BAND_LIMIT_1_4     = 0x10,
    LBR_FLAG_BAND_LIMIT_1_8     = 0x18,
    LBR_FLAG_BAND_LIMIT_NONE    = 0x14,
    LBR_FLAG_BAND_LIMIT_MASK    = 0x1c,
    LBR_FLAG_DMIX_STEREO        = 0x20,
    LBR_FLAG_DMIX_MULTI_CH      = 0x40
};

enum LBRChunkTypes {
    LBR_CHUNK_NULL              = 0x00,
    LBR_CHUNK_PAD               = 0x01,
    LBR_CHUNK_FRAME             = 0x04,
    LBR_CHUNK_FRAME_NO_CSUM     = 0x06,
    LBR_CHUNK_LFE               = 0x0a,
    LBR_CHUNK_ECS               = 0x0b,
    LBR_CHUNK_RESERVED_1        = 0x0c,
    LBR_CHUNK_RESERVED_2        = 0x0d,
    LBR_CHUNK_SCF               = 0x0e,
    LBR_CHUNK_TONAL             = 0x10,
    LBR_CHUNK_TONAL_GRP_1       = 0x11,
    LBR_CHUNK_TONAL_GRP_2       = 0x12,
    LBR_CHUNK_TONAL_GRP_3       = 0x13,
    LBR_CHUNK_TONAL_GRP_4       = 0x14,
    LBR_CHUNK_TONAL_GRP_5       = 0x15,
    LBR_CHUNK_TONAL_SCF         = 0x16,
    LBR_CHUNK_TONAL_SCF_GRP_1   = 0x17,
    LBR_CHUNK_TONAL_SCF_GRP_2   = 0x18,
    LBR_CHUNK_TONAL_SCF_GRP_3   = 0x19,
    LBR_CHUNK_TONAL_SCF_GRP_4   = 0x1a,
    LBR_CHUNK_TONAL_SCF_GRP_5   = 0x1b,
    LBR_CHUNK_RES_GRID_LR       = 0x30,
    LBR_CHUNK_RES_GRID_LR_LAST  = 0x3f,
    LBR_CHUNK_RES_GRID_HR       = 0x40,
    LBR_CHUNK_RES_GRID_HR_LAST  = 0x4f,
    LBR_CHUNK_RES_TS_1          = 0x50,
    LBR_CHUNK_RES_TS_1_LAST     = 0x5f,
    LBR_CHUNK_RES_TS_2          = 0x60,
    LBR_CHUNK_RES_TS_2_LAST     = 0x6f,
    LBR_CHUNK_EXTENSION         = 0x7f
};

typedef struct LBRChunk {
    int id, len;
    const uint8_t *data;
} LBRChunk;

static const int8_t channel_reorder_nolfe[7][5] = {
    { 0, -1, -1, -1, -1 },  // C
    { 0,  1, -1, -1, -1 },  // LR
    { 0,  1,  2, -1, -1 },  // LR C
    { 0,  1, -1, -1, -1 },  // LsRs
    { 1,  2,  0, -1, -1 },  // LsRs C
    { 0,  1,  2,  3, -1 },  // LR LsRs
    { 0,  1,  3,  4,  2 },  // LR LsRs C
};

static const int8_t channel_reorder_lfe[7][5] = {
    { 0, -1, -1, -1, -1 },  // C
    { 0,  1, -1, -1, -1 },  // LR
    { 0,  1,  2, -1, -1 },  // LR C
    { 1,  2, -1, -1, -1 },  // LsRs
    { 2,  3,  0, -1, -1 },  // LsRs C
    { 0,  1,  3,  4, -1 },  // LR LsRs
    { 0,  1,  4,  5,  2 },  // LR LsRs C
};

static const uint8_t lfe_index[7] = {
    1, 2, 3, 0, 1, 2, 3
};

static const uint16_t channel_layouts[7] = {
    AV_CH_LAYOUT_MONO,
    AV_CH_LAYOUT_STEREO,
    AV_CH_LAYOUT_SURROUND,
    AV_CH_SIDE_LEFT | AV_CH_SIDE_RIGHT,
    AV_CH_FRONT_CENTER | AV_CH_SIDE_LEFT | AV_CH_SIDE_RIGHT,
    AV_CH_LAYOUT_2_2,
    AV_CH_LAYOUT_5POINT0
};

static float    cos_tab[256];
static const float lpc_tab[16] = {
    /* lpc_tab[i] = sin((i - 8) * (M_PI / ((i < 8) ? 17 : 15))) */
    -0.995734176295034521871191178905, -0.961825643172819070408796290732,
    -0.895163291355062322067016499754, -0.798017227280239503332805112796,
    -0.673695643646557211712691912426, -0.526432162877355800244607799141,
    -0.361241666187152948744714596184, -0.183749517816570331574408839621,
     0.0,                               0.207911690817759337101742284405,
     0.406736643075800207753985990341,  0.587785252292473129168705954639,
     0.743144825477394235014697048974,  0.866025403784438646763723170753,
     0.951056516295153572116439333379,  0.994521895368273336922691944981
};

av_cold void ff_dca_lbr_init_tables(void)
{
    int i;

    for (i = 0; i < 256; i++)
        cos_tab[i] = cos(M_PI * i / 128);
}

static int parse_lfe_24(DCALbrDecoder *s)
{
    int step_max = FF_ARRAY_ELEMS(ff_dca_lfe_step_size_24) - 1;
    int i, ps, si, code, step_i;
    float step, value, delta;

    ps = get_bits(&s->gb, 24);
    si = ps >> 23;

    value = (((ps & 0x7fffff) ^ -si) + si) * (1.0f / 0x7fffff);

    step_i = get_bits(&s->gb, 8);
    if (step_i > step_max) {
        av_log(s->avctx, AV_LOG_ERROR, "Invalid LFE step size index\n");
        return AVERROR_INVALIDDATA;
    }

    step = ff_dca_lfe_step_size_24[step_i];

    for (i = 0; i < 64; i++) {
        code = get_bits(&s->gb, 6);

        delta = step * 0.03125f;
        if (code & 16)
            delta += step;
        if (code & 8)
            delta += step * 0.5f;
        if (code & 4)
            delta += step * 0.25f;
        if (code & 2)
            delta += step * 0.125f;
        if (code & 1)
            delta += step * 0.0625f;

        if (code & 32) {
            value -= delta;
            if (value < -3.0f)
                value = -3.0f;
        } else {
            value += delta;
            if (value > 3.0f)
                value = 3.0f;
        }

        step_i += ff_dca_lfe_delta_index_24[code & 31];
        step_i = av_clip(step_i, 0, step_max);

        step = ff_dca_lfe_step_size_24[step_i];
        s->lfe_data[i] = value * s->lfe_scale;
    }

    return 0;
}

static int parse_lfe_16(DCALbrDecoder *s)
{
    int step_max = FF_ARRAY_ELEMS(ff_dca_lfe_step_size_16) - 1;
    int i, ps, si, code, step_i;
    float step, value, delta;

    ps = get_bits(&s->gb, 16);
    si = ps >> 15;

    value = (((ps & 0x7fff) ^ -si) + si) * (1.0f / 0x7fff);

    step_i = get_bits(&s->gb, 8);
    if (step_i > step_max) {
        av_log(s->avctx, AV_LOG_ERROR, "Invalid LFE step size index\n");
        return AVERROR_INVALIDDATA;
    }

    step = ff_dca_lfe_step_size_16[step_i];

    for (i = 0; i < 64; i++) {
        code = get_bits(&s->gb, 4);

        delta = step * 0.125f;
        if (code & 4)
            delta += step;
        if (code & 2)
            delta += step * 0.5f;
        if (code & 1)
            delta += step * 0.25f;

        if (code & 8) {
            value -= delta;
            if (value < -3.0f)
                value = -3.0f;
        } else {
            value += delta;
            if (value > 3.0f)
                value = 3.0f;
        }

        step_i += ff_dca_lfe_delta_index_16[code & 7];
        step_i = av_clip(step_i, 0, step_max);

        step = ff_dca_lfe_step_size_16[step_i];
        s->lfe_data[i] = value * s->lfe_scale;
    }

    return 0;
}

static int parse_lfe_chunk(DCALbrDecoder *s, LBRChunk *chunk)
{
    int ret;

    if (!(s->flags & LBR_FLAG_LFE_PRESENT))
        return 0;

    if (!chunk->len)
        return 0;

    ret = init_get_bits8(&s->gb, chunk->data, chunk->len);
    if (ret < 0)
        return ret;

    // Determine bit depth from chunk size
    if (chunk->len >= 52)
        return parse_lfe_24(s);
    if (chunk->len >= 35)
        return parse_lfe_16(s);

    av_log(s->avctx, AV_LOG_ERROR, "LFE chunk too short\n");
    return AVERROR_INVALIDDATA;
}

static inline int parse_vlc(GetBitContext *s, const VLC *vlc,
                            int nb_bits, int max_depth)
{
    int v = get_vlc2(s, vlc->table, nb_bits, max_depth);
    if (v >= 0)
        return v;
    // Rare value
    return get_bits(s, get_bits(s, 3) + 1);
}

static int parse_tonal(DCALbrDecoder *s, int group)
{
    unsigned int amp[DCA_LBR_CHANNELS_TOTAL];
    unsigned int phs[DCA_LBR_CHANNELS_TOTAL];
    unsigned int diff, main_amp, shift;
    int sf, sf_idx, ch, main_ch, freq;
    int ch_nbits = av_ceil_log2(s->nchannels_total);

    // Parse subframes for this group
    for (sf = 0; sf < 1 << group; sf += diff ? 8 : 1) {
        sf_idx = ((s->framenum << group) + sf) & 31;
        s->tonal_bounds[group][sf_idx][0] = s->ntones;

        // Parse tones for this subframe
        for (freq = 1;; freq++) {
            if (get_bits_left(&s->gb) < 1) {
                av_log(s->avctx, AV_LOG_ERROR, "Tonal group chunk too short\n");
                return AVERROR_INVALIDDATA;
            }

            diff = parse_vlc(&s->gb, &ff_dca_vlc_tnl_grp[group], DCA_TNL_GRP_VLC_BITS, 2);
            if (diff >= FF_ARRAY_ELEMS(ff_dca_fst_amp)) {
                av_log(s->avctx, AV_LOG_ERROR, "Invalid tonal frequency diff\n");
                return AVERROR_INVALIDDATA;
            }

            diff = get_bitsz(&s->gb, diff >> 2) + ff_dca_fst_amp[diff];
            if (diff <= 1)
                break;  // End of subframe

            freq += diff - 2;
            if (freq >> (5 - group) > s->nsubbands * 4 - 6) {
                av_log(s->avctx, AV_LOG_ERROR, "Invalid spectral line offset\n");
                return AVERROR_INVALIDDATA;
            }

            // Main channel
            main_ch = get_bitsz(&s->gb, ch_nbits);
            main_amp = parse_vlc(&s->gb, &ff_dca_vlc_tnl_scf, DCA_TNL_SCF_VLC_BITS, 2)
                + s->tonal_scf[ff_dca_freq_to_sb[freq >> (7 - group)]]
                + s->limited_range - 2;
            amp[main_ch] = main_amp < AMP_MAX ? main_amp : 0;
            phs[main_ch] = get_bits(&s->gb, 3);

            // Secondary channels
            for (ch = 0; ch < s->nchannels_total; ch++) {
                if (ch == main_ch)
                    continue;
                if (get_bits1(&s->gb)) {
                    amp[ch] = amp[main_ch] - parse_vlc(&s->gb, &ff_dca_vlc_damp, DCA_DAMP_VLC_BITS, 1);
                    phs[ch] = phs[main_ch] - parse_vlc(&s->gb, &ff_dca_vlc_dph,  DCA_DPH_VLC_BITS,  1);
                } else {
                    amp[ch] = 0;
                    phs[ch] = 0;
                }
            }

            if (amp[main_ch]) {
                // Allocate new tone
                DCALbrTone *t = &s->tones[s->ntones];
                s->ntones = (s->ntones + 1) & (DCA_LBR_TONES - 1);

                t->x_freq = freq >> (5 - group);
                t->f_delt = (freq & ((1 << (5 - group)) - 1)) << group;
                t->ph_rot = 256 - (t->x_freq & 1) * 128 - t->f_delt * 4;

                shift = ff_dca_ph0_shift[(t->x_freq & 3) * 2 + (freq & 1)]
                    - ((t->ph_rot << (5 - group)) - t->ph_rot);

                for (ch = 0; ch < s->nchannels; ch++) {
                    t->amp[ch] = amp[ch] < AMP_MAX ? amp[ch] : 0;
                    t->phs[ch] = 128 - phs[ch] * 32 + shift;
                }
            }
        }

        s->tonal_bounds[group][sf_idx][1] = s->ntones;
    }

    return 0;
}

static int parse_tonal_chunk(DCALbrDecoder *s, LBRChunk *chunk)
{
    int sb, group, ret;

    if (!chunk->len)
        return 0;

    ret = init_get_bits8(&s->gb, chunk->data, chunk->len);

    if (ret < 0)
        return ret;

    // Scale factors
    if (chunk->id == LBR_CHUNK_SCF || chunk->id == LBR_CHUNK_TONAL_SCF) {
        if (get_bits_left(&s->gb) < 36) {
            av_log(s->avctx, AV_LOG_ERROR, "Tonal scale factor chunk too short\n");
            return AVERROR_INVALIDDATA;
        }
        for (sb = 0; sb < 6; sb++)
            s->tonal_scf[sb] = get_bits(&s->gb, 6);
    }

    // Tonal groups
    if (chunk->id == LBR_CHUNK_TONAL || chunk->id == LBR_CHUNK_TONAL_SCF)
        for (group = 0; group < 5; group++) {
            ret = parse_tonal(s, group);
            if (ret < 0)
                return ret;
        }

    return 0;
}

static int parse_tonal_group(DCALbrDecoder *s, LBRChunk *chunk)
{
    int ret;

    if (!chunk->len)
        return 0;

    ret = init_get_bits8(&s->gb, chunk->data, chunk->len);
    if (ret < 0)
        return ret;

    return parse_tonal(s, chunk->id);
}

/**
 * Check point to ensure that enough bits are left. Aborts decoding
 * by skipping to the end of chunk otherwise.
 */
static int ensure_bits(GetBitContext *s, int n)
{
    int left = get_bits_left(s);
    if (left < 0)
        return AVERROR_INVALIDDATA;
    if (left < n) {
        skip_bits_long(s, left);
        return 1;
    }
    return 0;
}

static int parse_scale_factors(DCALbrDecoder *s, uint8_t *scf)
{
    int i, sf, prev, next, dist;

    // Truncated scale factors remain zero
    if (ensure_bits(&s->gb, 20))
        return 0;

    // Initial scale factor
    prev = parse_vlc(&s->gb, &ff_dca_vlc_fst_rsd_amp, DCA_FST_RSD_VLC_BITS, 2);

    for (sf = 0; sf < 7; sf += dist) {
        scf[sf] = prev; // Store previous value

        if (ensure_bits(&s->gb, 20))
            return 0;

        // Interpolation distance
        dist = parse_vlc(&s->gb, &ff_dca_vlc_rsd_apprx, DCA_RSD_APPRX_VLC_BITS, 1) + 1;
        if (dist > 7 - sf) {
            av_log(s->avctx, AV_LOG_ERROR, "Invalid scale factor distance\n");
            return AVERROR_INVALIDDATA;
        }

        if (ensure_bits(&s->gb, 20))
            return 0;

        // Final interpolation point
        next = parse_vlc(&s->gb, &ff_dca_vlc_rsd_amp, DCA_RSD_AMP_VLC_BITS, 2);

        if (next & 1)
            next = prev + ((next + 1) >> 1);
        else
            next = prev - ( next      >> 1);

        // Interpolate
        switch (dist) {
        case 2:
            if (next > prev)
                scf[sf + 1] = prev + ((next - prev) >> 1);
            else
                scf[sf + 1] = prev - ((prev - next) >> 1);
            break;

        case 4:
            if (next > prev) {
                scf[sf + 1] = prev + ( (next - prev)      >> 2);
                scf[sf + 2] = prev + ( (next - prev)      >> 1);
                scf[sf + 3] = prev + (((next - prev) * 3) >> 2);
            } else {
                scf[sf + 1] = prev - ( (prev - next)      >> 2);
                scf[sf + 2] = prev - ( (prev - next)      >> 1);
                scf[sf + 3] = prev - (((prev - next) * 3) >> 2);
            }
            break;

        default:
            for (i = 1; i < dist; i++)
                scf[sf + i] = prev + (next - prev) * i / dist;
            break;
        }

        prev = next;
    }

    scf[sf] = next; // Store final value

    return 0;
}

static int parse_st_code(GetBitContext *s, int min_v)
{
    unsigned int v = parse_vlc(s, &ff_dca_vlc_st_grid, DCA_ST_GRID_VLC_BITS, 2) + min_v;

    if (v & 1)
        v = 16 + (v >> 1);
    else
        v = 16 - (v >> 1);

    if (v >= FF_ARRAY_ELEMS(ff_dca_st_coeff))
        v = 16;
    return v;
}

static int parse_grid_1_chunk(DCALbrDecoder *s, LBRChunk *chunk, int ch1, int ch2)
{
    int ch, sb, sf, nsubbands, ret;

    if (!chunk->len)
        return 0;

    ret = init_get_bits8(&s->gb, chunk->data, chunk->len);
    if (ret < 0)
        return ret;

    // Scale factors
    nsubbands = ff_dca_scf_to_grid_1[s->nsubbands - 1] + 1;
    for (sb = 2; sb < nsubbands; sb++) {
        ret = parse_scale_factors(s, s->grid_1_scf[ch1][sb]);
        if (ret < 0)
            return ret;
        if (ch1 != ch2 && ff_dca_grid_1_to_scf[sb] < s->min_mono_subband) {
            ret = parse_scale_factors(s, s->grid_1_scf[ch2][sb]);
            if (ret < 0)
                return ret;
        }
    }

    if (get_bits_left(&s->gb) < 1)
        return 0;   // Should not happen, but a sample exists that proves otherwise

    // Average values for third grid
    for (sb = 0; sb < s->nsubbands - 4; sb++) {
        s->grid_3_avg[ch1][sb] = parse_vlc(&s->gb, &ff_dca_vlc_avg_g3, DCA_AVG_G3_VLC_BITS, 2) - 16;
        if (ch1 != ch2) {
            if (sb + 4 < s->min_mono_subband)
                s->grid_3_avg[ch2][sb] = parse_vlc(&s->gb, &ff_dca_vlc_avg_g3, DCA_AVG_G3_VLC_BITS, 2) - 16;
            else
                s->grid_3_avg[ch2][sb] = s->grid_3_avg[ch1][sb];
        }
    }

    if (get_bits_left(&s->gb) < 0) {
        av_log(s->avctx, AV_LOG_ERROR, "First grid chunk too short\n");
        return AVERROR_INVALIDDATA;
    }

    // Stereo image for partial mono mode
    if (ch1 != ch2) {
        int min_v[2];

        if (ensure_bits(&s->gb, 8))
            return 0;

        min_v[0] = get_bits(&s->gb, 4);
        min_v[1] = get_bits(&s->gb, 4);

        nsubbands = (s->nsubbands - s->min_mono_subband + 3) / 4;
        for (sb = 0; sb < nsubbands; sb++)
            for (ch = ch1; ch <= ch2; ch++)
                for (sf = 1; sf <= 4; sf++)
                    s->part_stereo[ch][sb][sf] = parse_st_code(&s->gb, min_v[ch - ch1]);

        if (get_bits_left(&s->gb) >= 0)
            s->part_stereo_pres |= 1 << ch1;
    }

    // Low resolution spatial information is not decoded

    return 0;
}

static int parse_grid_1_sec_ch(DCALbrDecoder *s, int ch2)
{
    int sb, nsubbands, ret;

    // Scale factors
    nsubbands = ff_dca_scf_to_grid_1[s->nsubbands - 1] + 1;
    for (sb = 2; sb < nsubbands; sb++) {
        if (ff_dca_grid_1_to_scf[sb] >= s->min_mono_subband) {
            ret = parse_scale_factors(s, s->grid_1_scf[ch2][sb]);
            if (ret < 0)
                return ret;
        }
    }

    // Average values for third grid
    for (sb = 0; sb < s->nsubbands - 4; sb++) {
        if (sb + 4 >= s->min_mono_subband) {
            if (ensure_bits(&s->gb, 20))
                return 0;
            s->grid_3_avg[ch2][sb] = parse_vlc(&s->gb, &ff_dca_vlc_avg_g3, DCA_AVG_G3_VLC_BITS, 2) - 16;
        }
    }

    return 0;
}

static void parse_grid_3(DCALbrDecoder *s, int ch1, int ch2, int sb, int flag)
{
    int i, ch;

    for (ch = ch1; ch <= ch2; ch++) {
        if ((ch != ch1 && sb + 4 >= s->min_mono_subband) != flag)
            continue;

        if (s->grid_3_pres[ch] & (1U << sb))
            continue;   // Already parsed

        for (i = 0; i < 8; i++) {
            if (ensure_bits(&s->gb, 20))
                return;
            s->grid_3_scf[ch][sb][i] = parse_vlc(&s->gb, &ff_dca_vlc_grid_3, DCA_GRID_VLC_BITS, 2) - 16;
        }

        // Flag scale factors for this subband parsed
        s->grid_3_pres[ch] |= 1U << sb;
    }
}

static float lbr_rand(DCALbrDecoder *s, int sb)
{
    s->lbr_rand = 1103515245U * s->lbr_rand + 12345U;
    return s->lbr_rand * s->sb_scf[sb];
}

/**
 * Parse time samples for one subband, filling truncated samples with randomness
 */
static void parse_ch(DCALbrDecoder *s, int ch, int sb, int quant_level, int flag)
{
    float *samples = s->time_samples[ch][sb];
    int i, j, code, nblocks, coding_method;

    if (ensure_bits(&s->gb, 20))
        return; // Too few bits left

    coding_method = get_bits1(&s->gb);

    switch (quant_level) {
    case 1:
        nblocks = FFMIN(get_bits_left(&s->gb) / 8, DCA_LBR_TIME_SAMPLES / 8);
        for (i = 0; i < nblocks; i++, samples += 8) {
            code = get_bits(&s->gb, 8);
            for (j = 0; j < 8; j++)
                samples[j] = ff_dca_rsd_level_2a[(code >> j) & 1];
        }
        i = nblocks * 8;
        break;

    case 2:
        if (coding_method) {
            for (i = 0; i < DCA_LBR_TIME_SAMPLES && get_bits_left(&s->gb) >= 2; i++) {
                if (get_bits1(&s->gb))
                    samples[i] = ff_dca_rsd_level_2b[get_bits1(&s->gb)];
                else
                    samples[i] = 0;
            }
        } else {
            nblocks = FFMIN(get_bits_left(&s->gb) / 8, (DCA_LBR_TIME_SAMPLES + 4) / 5);
            for (i = 0; i < nblocks; i++, samples += 5) {
                code = ff_dca_rsd_pack_5_in_8[get_bits(&s->gb, 8)];
                for (j = 0; j < 5; j++)
                    samples[j] = ff_dca_rsd_level_3[(code >> j * 2) & 3];
            }
            i = nblocks * 5;
        }
        break;

    case 3:
        nblocks = FFMIN(get_bits_left(&s->gb) / 7, (DCA_LBR_TIME_SAMPLES + 2) / 3);
        for (i = 0; i < nblocks; i++, samples += 3) {
            code = get_bits(&s->gb, 7);
            for (j = 0; j < 3; j++)
                samples[j] = ff_dca_rsd_level_5[ff_dca_rsd_pack_3_in_7[code][j]];
        }
        i = nblocks * 3;
        break;

    case 4:
        for (i = 0; i < DCA_LBR_TIME_SAMPLES && get_bits_left(&s->gb) >= 6; i++)
            samples[i] = ff_dca_rsd_level_8[get_vlc2(&s->gb, ff_dca_vlc_rsd.table, 6, 1)];
        break;

    case 5:
        nblocks = FFMIN(get_bits_left(&s->gb) / 4, DCA_LBR_TIME_SAMPLES);
        for (i = 0; i < nblocks; i++)
            samples[i] = ff_dca_rsd_level_16[get_bits(&s->gb, 4)];
        break;

    default:
        av_assert0(0);
    }

    if (flag && get_bits_left(&s->gb) < 20)
        return; // Skip incomplete mono subband

    for (; i < DCA_LBR_TIME_SAMPLES; i++)
        s->time_samples[ch][sb][i] = lbr_rand(s, sb);

    s->ch_pres[ch] |= 1U << sb;
}

static int parse_ts(DCALbrDecoder *s, int ch1, int ch2,
                    int start_sb, int end_sb, int flag)
{
    int sb, sb_g3, sb_reorder, quant_level;

    for (sb = start_sb; sb < end_sb; sb++) {
        // Subband number before reordering
        if (sb < 6) {
            sb_reorder = sb;
        } else if (flag && sb < s->max_mono_subband) {
            sb_reorder = s->sb_indices[sb];
        } else {
            if (ensure_bits(&s->gb, 28))
                break;
            sb_reorder = get_bits(&s->gb, s->limited_range + 3);
            if (sb_reorder < 6)
                sb_reorder = 6;
            s->sb_indices[sb] = sb_reorder;
        }
        if (sb_reorder >= s->nsubbands)
            return AVERROR_INVALIDDATA;

        // Third grid scale factors
        if (sb == 12) {
            for (sb_g3 = 0; sb_g3 < s->g3_avg_only_start_sb - 4; sb_g3++)
                parse_grid_3(s, ch1, ch2, sb_g3, flag);
        } else if (sb < 12 && sb_reorder >= 4) {
            parse_grid_3(s, ch1, ch2, sb_reorder - 4, flag);
        }

        // Secondary channel flags
        if (ch1 != ch2) {
            if (ensure_bits(&s->gb, 20))
                break;
            if (!flag || sb_reorder >= s->max_mono_subband)
                s->sec_ch_sbms[ch1 / 2][sb_reorder] = get_bits(&s->gb, 8);
            if (flag && sb_reorder >= s->min_mono_subband)
                s->sec_ch_lrms[ch1 / 2][sb_reorder] = get_bits(&s->gb, 8);
        }

        quant_level = s->quant_levels[ch1 / 2][sb];
        if (!quant_level)
            return AVERROR_INVALIDDATA;

        // Time samples for one or both channels
        if (sb < s->max_mono_subband && sb_reorder >= s->min_mono_subband) {
            if (!flag)
                parse_ch(s, ch1, sb_reorder, quant_level, 0);
            else if (ch1 != ch2)
                parse_ch(s, ch2, sb_reorder, quant_level, 1);
        } else {
            parse_ch(s, ch1, sb_reorder, quant_level, 0);
            if (ch1 != ch2)
                parse_ch(s, ch2, sb_reorder, quant_level, 0);
        }
    }

    return 0;
}

/**
 * Convert from reflection coefficients to direct form coefficients
 */
static void convert_lpc(float *coeff, const int *codes)
{
    int i, j;

    for (i = 0; i < 8; i++) {
        float rc = lpc_tab[codes[i]];
        for (j = 0; j < (i + 1) / 2; j++) {
            float tmp1 = coeff[    j    ];
            float tmp2 = coeff[i - j - 1];
            coeff[    j    ] = tmp1 + rc * tmp2;
            coeff[i - j - 1] = tmp2 + rc * tmp1;
        }
        coeff[i] = rc;
    }
}

static int parse_lpc(DCALbrDecoder *s, int ch1, int ch2, int start_sb, int end_sb)
{
    int f = s->framenum & 1;
    int i, sb, ch, codes[16];

    // First two subbands have two sets of coefficients, third subband has one
    for (sb = start_sb; sb < end_sb; sb++) {
        int ncodes = 8 * (1 + (sb < 2));
        for (ch = ch1; ch <= ch2; ch++) {
            if (ensure_bits(&s->gb, 4 * ncodes))
                return 0;
            for (i = 0; i < ncodes; i++)
                codes[i] = get_bits(&s->gb, 4);
            for (i = 0; i < ncodes / 8; i++)
                convert_lpc(s->lpc_coeff[f][ch][sb][i], &codes[i * 8]);
        }
    }

    return 0;
}

static int parse_high_res_grid(DCALbrDecoder *s, LBRChunk *chunk, int ch1, int ch2)
{
    int quant_levels[DCA_LBR_SUBBANDS];
    int sb, ch, ol, st, max_sb, profile, ret;

    if (!chunk->len)
        return 0;

    ret = init_get_bits8(&s->gb, chunk->data, chunk->len);
    if (ret < 0)
        return ret;

    // Quantizer profile
    profile = get_bits(&s->gb, 8);
    // Overall level
    ol = (profile >> 3) & 7;
    // Steepness
    st = profile >> 6;
    // Max energy subband
    max_sb = profile & 7;

    // Calculate quantization levels
    for (sb = 0; sb < s->nsubbands; sb++) {
        int f = sb * s->limited_rate / s->nsubbands;
        int a = 18000 / (12 * f / 1000 + 100 + 40 * st) + 20 * ol;
        if (a <= 95)
            quant_levels[sb] = 1;
        else if (a <= 140)
            quant_levels[sb] = 2;
        else if (a <= 180)
            quant_levels[sb] = 3;
        else if (a <= 230)
            quant_levels[sb] = 4;
        else
            quant_levels[sb] = 5;
    }

    // Reorder quantization levels for lower subbands
    for (sb = 0; sb < 8; sb++)
        s->quant_levels[ch1 / 2][sb] = quant_levels[ff_dca_sb_reorder[max_sb][sb]];
    for (; sb < s->nsubbands; sb++)
        s->quant_levels[ch1 / 2][sb] = quant_levels[sb];

    // LPC for the first two subbands
    ret = parse_lpc(s, ch1, ch2, 0, 2);
    if (ret < 0)
        return ret;

    // Time-samples for the first two subbands of main channel
    ret = parse_ts(s, ch1, ch2, 0, 2, 0);
    if (ret < 0)
        return ret;

    // First two bands of the first grid
    for (sb = 0; sb < 2; sb++)
        for (ch = ch1; ch <= ch2; ch++)
            if ((ret = parse_scale_factors(s, s->grid_1_scf[ch][sb])) < 0)
                return ret;

    return 0;
}

static int parse_grid_2(DCALbrDecoder *s, int ch1, int ch2,
                        int start_sb, int end_sb, int flag)
{
    int i, j, sb, ch, nsubbands;

    nsubbands = ff_dca_scf_to_grid_2[s->nsubbands - 1] + 1;
    if (end_sb > nsubbands)
        end_sb = nsubbands;

    for (sb = start_sb; sb < end_sb; sb++) {
        for (ch = ch1; ch <= ch2; ch++) {
            uint8_t *g2_scf = s->grid_2_scf[ch][sb];

            if ((ch != ch1 && ff_dca_grid_2_to_scf[sb] >= s->min_mono_subband) != flag) {
                if (!flag)
                    memcpy(g2_scf, s->grid_2_scf[ch1][sb], 64);
                continue;
            }

            // Scale factors in groups of 8
            for (i = 0; i < 8; i++, g2_scf += 8) {
                if (get_bits_left(&s->gb) < 1) {
                    memset(g2_scf, 0, 64 - i * 8);
                    break;
                }
                // Bit indicating if whole group has zero values
                if (get_bits1(&s->gb)) {
                    for (j = 0; j < 8; j++) {
                        if (ensure_bits(&s->gb, 20))
                            break;
                        g2_scf[j] = parse_vlc(&s->gb, &ff_dca_vlc_grid_2, DCA_GRID_VLC_BITS, 2);
                    }
                } else {
                    memset(g2_scf, 0, 8);
                }
            }
        }
    }

    return 0;
}

static int parse_ts1_chunk(DCALbrDecoder *s, LBRChunk *chunk, int ch1, int ch2)
{
    int ret;
    if (!chunk->len)
        return 0;
    if ((ret = init_get_bits8(&s->gb, chunk->data, chunk->len)) < 0)
        return ret;
    if ((ret = parse_lpc(s, ch1, ch2, 2, 3)) < 0)
        return ret;
    if ((ret = parse_ts(s, ch1, ch2, 2, 4, 0)) < 0)
        return ret;
    if ((ret = parse_grid_2(s, ch1, ch2, 0, 1, 0)) < 0)
        return ret;
    if ((ret = parse_ts(s, ch1, ch2, 4, 6, 0)) < 0)
        return ret;
    return 0;
}

static int parse_ts2_chunk(DCALbrDecoder *s, LBRChunk *chunk, int ch1, int ch2)
{
    int ret;

    if (!chunk->len)
        return 0;
    if ((ret = init_get_bits8(&s->gb, chunk->data, chunk->len)) < 0)
        return ret;
    if ((ret = parse_grid_2(s, ch1, ch2, 1, 3, 0)) < 0)
        return ret;
    if ((ret = parse_ts(s, ch1, ch2, 6, s->max_mono_subband, 0)) < 0)
        return ret;
    if (ch1 != ch2) {
        if ((ret = parse_grid_1_sec_ch(s, ch2)) < 0)
            return ret;
        if ((ret = parse_grid_2(s, ch1, ch2, 0, 3, 1)) < 0)
            return ret;
    }
    if ((ret = parse_ts(s, ch1, ch2, s->min_mono_subband, s->nsubbands, 1)) < 0)
        return ret;
    return 0;
}

static int init_sample_rate(DCALbrDecoder *s)
{
    double scale = (-1.0 / (1 << 17)) * sqrt(1 << (2 - s->limited_range));
    int i, br_per_ch = s->bit_rate_scaled / s->nchannels_total;
    int ret;

    ff_mdct_end(&s->imdct);

    ret = ff_mdct_init(&s->imdct, s->freq_range + 6, 1, scale);
    if (ret < 0)
        return ret;

    for (i = 0; i < 32 << s->freq_range; i++)
        s->window[i] = ff_dca_long_window[i << (2 - s->freq_range)];

    if (br_per_ch < 14000)
        scale = 0.85;
    else if (br_per_ch < 32000)
        scale = (br_per_ch - 14000) * (1.0 / 120000) + 0.85;
    else
        scale = 1.0;

    scale *= 1.0 / INT_MAX;

    for (i = 0; i < s->nsubbands; i++) {
        if (i < 2)
            s->sb_scf[i] = 0;   // The first two subbands are always zero
        else if (i < 5)
            s->sb_scf[i] = (i - 1) * 0.25 * 0.785 * scale;
        else
            s->sb_scf[i] = 0.785 * scale;
    }

    s->lfe_scale = (16 << s->freq_range) * 0.0000078265894;

    return 0;
}

static int alloc_sample_buffer(DCALbrDecoder *s)
{
    // Reserve space for history and padding
    int nchsamples = DCA_LBR_TIME_SAMPLES + DCA_LBR_TIME_HISTORY * 2;
    int nsamples = nchsamples * s->nchannels * s->nsubbands;
    int ch, sb;
    float *ptr;

    // Reallocate time sample buffer
    av_fast_mallocz(&s->ts_buffer, &s->ts_size, nsamples * sizeof(float));
    if (!s->ts_buffer)
        return AVERROR(ENOMEM);

    ptr = s->ts_buffer + DCA_LBR_TIME_HISTORY;
    for (ch = 0; ch < s->nchannels; ch++) {
        for (sb = 0; sb < s->nsubbands; sb++) {
            s->time_samples[ch][sb] = ptr;
            ptr += nchsamples;
        }
    }

    return 0;
}

static int parse_decoder_init(DCALbrDecoder *s, GetByteContext *gb)
{
    int old_rate = s->sample_rate;
    int old_band_limit = s->band_limit;
    int old_nchannels = s->nchannels;
    int version, bit_rate_hi;
    unsigned int sr_code;

    // Sample rate of LBR audio
    sr_code = bytestream2_get_byte(gb);
    if (sr_code >= FF_ARRAY_ELEMS(ff_dca_sampling_freqs)) {
        av_log(s->avctx, AV_LOG_ERROR, "Invalid LBR sample rate\n");
        return AVERROR_INVALIDDATA;
    }
    s->sample_rate = ff_dca_sampling_freqs[sr_code];
    if (s->sample_rate > 48000) {
        avpriv_report_missing_feature(s->avctx, "%d Hz LBR sample rate", s->sample_rate);
        return AVERROR_PATCHWELCOME;
    }

    // LBR speaker mask
    s->ch_mask = bytestream2_get_le16(gb);
    if (!(s->ch_mask & 0x7)) {
        avpriv_report_missing_feature(s->avctx, "LBR channel mask %#x", s->ch_mask);
        return AVERROR_PATCHWELCOME;
    }
    if ((s->ch_mask & 0xfff0) && !(s->warned & 1)) {
        avpriv_report_missing_feature(s->avctx, "LBR channel mask %#x", s->ch_mask);
        s->warned |= 1;
    }

    // LBR bitstream version
    version = bytestream2_get_le16(gb);
    if ((version & 0xff00) != 0x0800) {
        avpriv_report_missing_feature(s->avctx, "LBR stream version %#x", version);
        return AVERROR_PATCHWELCOME;
    }

    // Flags for LBR decoder initialization
    s->flags = bytestream2_get_byte(gb);
    if (s->flags & LBR_FLAG_DMIX_MULTI_CH) {
        avpriv_report_missing_feature(s->avctx, "LBR multi-channel downmix");
        return AVERROR_PATCHWELCOME;
    }
    if ((s->flags & LBR_FLAG_LFE_PRESENT) && s->sample_rate != 48000) {
        if (!(s->warned & 2)) {
            avpriv_report_missing_feature(s->avctx, "%d Hz LFE interpolation", s->sample_rate);
            s->warned |= 2;
        }
        s->flags &= ~LBR_FLAG_LFE_PRESENT;
    }

    // Most significant bit rate nibbles
    bit_rate_hi = bytestream2_get_byte(gb);

    // Least significant original bit rate word
    s->bit_rate_orig = bytestream2_get_le16(gb) | ((bit_rate_hi & 0x0F) << 16);

    // Least significant scaled bit rate word
    s->bit_rate_scaled = bytestream2_get_le16(gb) | ((bit_rate_hi & 0xF0) << 12);

    // Setup number of fullband channels
    s->nchannels_total = ff_dca_count_chs_for_mask(s->ch_mask & ~DCA_SPEAKER_PAIR_LFE1);
    s->nchannels = FFMIN(s->nchannels_total, DCA_LBR_CHANNELS);

    // Setup band limit
    switch (s->flags & LBR_FLAG_BAND_LIMIT_MASK) {
    case LBR_FLAG_BAND_LIMIT_NONE:
        s->band_limit = 0;
        break;
    case LBR_FLAG_BAND_LIMIT_1_2:
        s->band_limit = 1;
        break;
    case LBR_FLAG_BAND_LIMIT_1_4:
        s->band_limit = 2;
        break;
    default:
        avpriv_report_missing_feature(s->avctx, "LBR band limit %#x", s->flags & LBR_FLAG_BAND_LIMIT_MASK);
        return AVERROR_PATCHWELCOME;
    }

    // Setup frequency range
    s->freq_range = ff_dca_freq_ranges[sr_code];

    // Setup resolution profile
    if (s->bit_rate_orig >= 44000 * (s->nchannels_total + 2))
        s->res_profile = 2;
    else if (s->bit_rate_orig >= 25000 * (s->nchannels_total + 2))
        s->res_profile = 1;
    else
        s->res_profile = 0;

    // Setup limited sample rate, number of subbands, etc
    s->limited_rate = s->sample_rate >> s->band_limit;
    s->limited_range = s->freq_range - s->band_limit;
    if (s->limited_range < 0) {
        av_log(s->avctx, AV_LOG_ERROR, "Invalid LBR band limit for frequency range\n");
        return AVERROR_INVALIDDATA;
    }

    s->nsubbands = 8 << s->limited_range;

    s->g3_avg_only_start_sb = s->nsubbands * ff_dca_avg_g3_freqs[s->res_profile] / (s->limited_rate / 2);
    if (s->g3_avg_only_start_sb > s->nsubbands)
        s->g3_avg_only_start_sb = s->nsubbands;

    s->min_mono_subband = s->nsubbands *  2000 / (s->limited_rate / 2);
    if (s->min_mono_subband > s->nsubbands)
        s->min_mono_subband = s->nsubbands;

    s->max_mono_subband = s->nsubbands * 14000 / (s->limited_rate / 2);
    if (s->max_mono_subband > s->nsubbands)
        s->max_mono_subband = s->nsubbands;

    // Handle change of sample rate
    if ((old_rate != s->sample_rate || old_band_limit != s->band_limit) && init_sample_rate(s) < 0)
        return AVERROR(ENOMEM);

    // Setup stereo downmix
    if (s->flags & LBR_FLAG_DMIX_STEREO) {
        DCAContext *dca = s->avctx->priv_data;

        if (s->nchannels_total < 3 || s->nchannels_total > DCA_LBR_CHANNELS_TOTAL - 2) {
            av_log(s->avctx, AV_LOG_ERROR, "Invalid number of channels for LBR stereo downmix\n");
            return AVERROR_INVALIDDATA;
        }

        // This decoder doesn't support ECS chunk
        if (dca->request_channel_layout != DCA_SPEAKER_LAYOUT_STEREO && !(s->warned & 4)) {
            avpriv_report_missing_feature(s->avctx, "Embedded LBR stereo downmix");
            s->warned |= 4;
        }

        // Account for extra downmixed channel pair
        s->nchannels_total += 2;
        s->nchannels = 2;
        s->ch_mask = DCA_SPEAKER_PAIR_LR;
        s->flags &= ~LBR_FLAG_LFE_PRESENT;
    }

    // Handle change of sample rate or number of channels
    if (old_rate != s->sample_rate
        || old_band_limit != s->band_limit
        || old_nchannels != s->nchannels) {
        if (alloc_sample_buffer(s) < 0)
            return AVERROR(ENOMEM);
        ff_dca_lbr_flush(s);
    }

    return 0;
}

int ff_dca_lbr_parse(DCALbrDecoder *s, const uint8_t *data, DCAExssAsset *asset)
{
    struct {
        LBRChunk    lfe;
        LBRChunk    tonal;
        LBRChunk    tonal_grp[5];
        LBRChunk    grid1[DCA_LBR_CHANNELS / 2];
        LBRChunk    hr_grid[DCA_LBR_CHANNELS / 2];
        LBRChunk    ts1[DCA_LBR_CHANNELS / 2];
        LBRChunk    ts2[DCA_LBR_CHANNELS / 2];
    } chunk = { {0} };

    GetByteContext gb;

    int i, ch, sb, sf, ret, group, chunk_id, chunk_len;

    bytestream2_init(&gb, data + asset->lbr_offset, asset->lbr_size);

    // LBR sync word
    if (bytestream2_get_be32(&gb) != DCA_SYNCWORD_LBR) {
        av_log(s->avctx, AV_LOG_ERROR, "Invalid LBR sync word\n");
        return AVERROR_INVALIDDATA;
    }

    // LBR header type
    switch (bytestream2_get_byte(&gb)) {
    case DCA_LBR_HEADER_SYNC_ONLY:
        if (!s->sample_rate) {
            av_log(s->avctx, AV_LOG_ERROR, "LBR decoder not initialized\n");
            return AVERROR_INVALIDDATA;
        }
        break;
    case DCA_LBR_HEADER_DECODER_INIT:
        if ((ret = parse_decoder_init(s, &gb)) < 0) {
            s->sample_rate = 0;
            return ret;
        }
        break;
    default:
        av_log(s->avctx, AV_LOG_ERROR, "Invalid LBR header type\n");
        return AVERROR_INVALIDDATA;
    }

    // LBR frame chunk header
    chunk_id = bytestream2_get_byte(&gb);
    chunk_len = (chunk_id & 0x80) ? bytestream2_get_be16(&gb) : bytestream2_get_byte(&gb);

    if (chunk_len > bytestream2_get_bytes_left(&gb)) {
        chunk_len = bytestream2_get_bytes_left(&gb);
        av_log(s->avctx, AV_LOG_WARNING, "LBR frame chunk was truncated\n");
        if (s->avctx->err_recognition & AV_EF_EXPLODE)
            return AVERROR_INVALIDDATA;
    }

    bytestream2_init(&gb, gb.buffer, chunk_len);

    switch (chunk_id & 0x7f) {
    case LBR_CHUNK_FRAME:
        if (s->avctx->err_recognition & (AV_EF_CRCCHECK | AV_EF_CAREFUL)) {
            int checksum = bytestream2_get_be16(&gb);
            uint16_t res = chunk_id;
            res += (chunk_len >> 8) & 0xff;
            res += chunk_len & 0xff;
            for (i = 0; i < chunk_len - 2; i++)
                res += gb.buffer[i];
            if (checksum != res) {
                av_log(s->avctx, AV_LOG_WARNING, "Invalid LBR checksum\n");
                if (s->avctx->err_recognition & AV_EF_EXPLODE)
                    return AVERROR_INVALIDDATA;
            }
        } else {
            bytestream2_skip(&gb, 2);
        }
        break;
    case LBR_CHUNK_FRAME_NO_CSUM:
        break;
    default:
        av_log(s->avctx, AV_LOG_ERROR, "Invalid LBR frame chunk ID\n");
        return AVERROR_INVALIDDATA;
    }

    // Clear current frame
    memset(s->quant_levels, 0, sizeof(s->quant_levels));
    memset(s->sb_indices, 0xff, sizeof(s->sb_indices));
    memset(s->sec_ch_sbms, 0, sizeof(s->sec_ch_sbms));
    memset(s->sec_ch_lrms, 0, sizeof(s->sec_ch_lrms));
    memset(s->ch_pres, 0, sizeof(s->ch_pres));
    memset(s->grid_1_scf, 0, sizeof(s->grid_1_scf));
    memset(s->grid_2_scf, 0, sizeof(s->grid_2_scf));
    memset(s->grid_3_avg, 0, sizeof(s->grid_3_avg));
    memset(s->grid_3_scf, 0, sizeof(s->grid_3_scf));
    memset(s->grid_3_pres, 0, sizeof(s->grid_3_pres));
    memset(s->tonal_scf, 0, sizeof(s->tonal_scf));
    memset(s->lfe_data, 0, sizeof(s->lfe_data));
    s->part_stereo_pres = 0;
    s->framenum = (s->framenum + 1) & 31;

    for (ch = 0; ch < s->nchannels; ch++) {
        for (sb = 0; sb < s->nsubbands / 4; sb++) {
            s->part_stereo[ch][sb][0] = s->part_stereo[ch][sb][4];
            s->part_stereo[ch][sb][4] = 16;
        }
    }

    memset(s->lpc_coeff[s->framenum & 1], 0, sizeof(s->lpc_coeff[0]));

    for (group = 0; group < 5; group++) {
        for (sf = 0; sf < 1 << group; sf++) {
            int sf_idx = ((s->framenum << group) + sf) & 31;
            s->tonal_bounds[group][sf_idx][0] =
            s->tonal_bounds[group][sf_idx][1] = s->ntones;
        }
    }

    // Parse chunk headers
    while (bytestream2_get_bytes_left(&gb) > 0) {
        chunk_id = bytestream2_get_byte(&gb);
        chunk_len = (chunk_id & 0x80) ? bytestream2_get_be16(&gb) : bytestream2_get_byte(&gb);
        chunk_id &= 0x7f;

        if (chunk_len > bytestream2_get_bytes_left(&gb)) {
            chunk_len = bytestream2_get_bytes_left(&gb);
            av_log(s->avctx, AV_LOG_WARNING, "LBR chunk %#x was truncated\n", chunk_id);
            if (s->avctx->err_recognition & AV_EF_EXPLODE)
                return AVERROR_INVALIDDATA;
        }

        switch (chunk_id) {
        case LBR_CHUNK_LFE:
            chunk.lfe.len  = chunk_len;
            chunk.lfe.data = gb.buffer;
            break;

        case LBR_CHUNK_SCF:
        case LBR_CHUNK_TONAL:
        case LBR_CHUNK_TONAL_SCF:
            chunk.tonal.id   = chunk_id;
            chunk.tonal.len  = chunk_len;
            chunk.tonal.data = gb.buffer;
            break;

        case LBR_CHUNK_TONAL_GRP_1:
        case LBR_CHUNK_TONAL_GRP_2:
        case LBR_CHUNK_TONAL_GRP_3:
        case LBR_CHUNK_TONAL_GRP_4:
        case LBR_CHUNK_TONAL_GRP_5:
            i = LBR_CHUNK_TONAL_GRP_5 - chunk_id;
            chunk.tonal_grp[i].id   = i;
            chunk.tonal_grp[i].len  = chunk_len;
            chunk.tonal_grp[i].data = gb.buffer;
            break;

        case LBR_CHUNK_TONAL_SCF_GRP_1:
        case LBR_CHUNK_TONAL_SCF_GRP_2:
        case LBR_CHUNK_TONAL_SCF_GRP_3:
        case LBR_CHUNK_TONAL_SCF_GRP_4:
        case LBR_CHUNK_TONAL_SCF_GRP_5:
            i = LBR_CHUNK_TONAL_SCF_GRP_5 - chunk_id;
            chunk.tonal_grp[i].id   = i;
            chunk.tonal_grp[i].len  = chunk_len;
            chunk.tonal_grp[i].data = gb.buffer;
            break;

        case LBR_CHUNK_RES_GRID_LR:
        case LBR_CHUNK_RES_GRID_LR + 1:
        case LBR_CHUNK_RES_GRID_LR + 2:
            i = chunk_id - LBR_CHUNK_RES_GRID_LR;
            chunk.grid1[i].len  = chunk_len;
            chunk.grid1[i].data = gb.buffer;
            break;

        case LBR_CHUNK_RES_GRID_HR:
        case LBR_CHUNK_RES_GRID_HR + 1:
        case LBR_CHUNK_RES_GRID_HR + 2:
            i = chunk_id - LBR_CHUNK_RES_GRID_HR;
            chunk.hr_grid[i].len  = chunk_len;
            chunk.hr_grid[i].data = gb.buffer;
            break;

        case LBR_CHUNK_RES_TS_1:
        case LBR_CHUNK_RES_TS_1 + 1:
        case LBR_CHUNK_RES_TS_1 + 2:
            i = chunk_id - LBR_CHUNK_RES_TS_1;
            chunk.ts1[i].len  = chunk_len;
            chunk.ts1[i].data = gb.buffer;
            break;

        case LBR_CHUNK_RES_TS_2:
        case LBR_CHUNK_RES_TS_2 + 1:
        case LBR_CHUNK_RES_TS_2 + 2:
            i = chunk_id - LBR_CHUNK_RES_TS_2;
            chunk.ts2[i].len  = chunk_len;
            chunk.ts2[i].data = gb.buffer;
            break;
        }

        bytestream2_skip(&gb, chunk_len);
    }

    // Parse the chunks
    ret = parse_lfe_chunk(s, &chunk.lfe);

    ret |= parse_tonal_chunk(s, &chunk.tonal);

    for (i = 0; i < 5; i++)
        ret |= parse_tonal_group(s, &chunk.tonal_grp[i]);

    for (i = 0; i < (s->nchannels + 1) / 2; i++) {
        int ch1 = i * 2;
        int ch2 = FFMIN(ch1 + 1, s->nchannels - 1);

        if (parse_grid_1_chunk (s, &chunk.grid1  [i], ch1, ch2) < 0 ||
            parse_high_res_grid(s, &chunk.hr_grid[i], ch1, ch2) < 0) {
            ret = -1;
            continue;
        }

        // TS chunks depend on both grids. TS_2 depends on TS_1.
        if (!chunk.grid1[i].len || !chunk.hr_grid[i].len || !chunk.ts1[i].len)
            continue;

        if (parse_ts1_chunk(s, &chunk.ts1[i], ch1, ch2) < 0 ||
            parse_ts2_chunk(s, &chunk.ts2[i], ch1, ch2) < 0) {
            ret = -1;
            continue;
        }
    }

    if (ret < 0 && (s->avctx->err_recognition & AV_EF_EXPLODE))
        return AVERROR_INVALIDDATA;

    return 0;
}

/**
 * Reconstruct high-frequency resolution grid from first and third grids
 */
static void decode_grid(DCALbrDecoder *s, int ch1, int ch2)
{
    int i, ch, sb;

    for (ch = ch1; ch <= ch2; ch++) {
        for (sb = 0; sb < s->nsubbands; sb++) {
            int g1_sb = ff_dca_scf_to_grid_1[sb];

            uint8_t *g1_scf_a = s->grid_1_scf[ch][g1_sb    ];
            uint8_t *g1_scf_b = s->grid_1_scf[ch][g1_sb + 1];

            int w1 = ff_dca_grid_1_weights[g1_sb    ][sb];
            int w2 = ff_dca_grid_1_weights[g1_sb + 1][sb];

            uint8_t *hr_scf = s->high_res_scf[ch][sb];

            if (sb < 4) {
                for (i = 0; i < 8; i++) {
                    int scf = w1 * g1_scf_a[i] + w2 * g1_scf_b[i];
                    hr_scf[i] = scf >> 7;
                }
            } else {
                int8_t *g3_scf = s->grid_3_scf[ch][sb - 4];
                int g3_avg = s->grid_3_avg[ch][sb - 4];

                for (i = 0; i < 8; i++) {
                    int scf = w1 * g1_scf_a[i] + w2 * g1_scf_b[i];
                    hr_scf[i] = (scf >> 7) - g3_avg - g3_scf[i];
                }
            }
        }
    }
}

/**
 * Fill unallocated subbands with randomness
 */
static void random_ts(DCALbrDecoder *s, int ch1, int ch2)
{
    int i, j, k, ch, sb;

    for (ch = ch1; ch <= ch2; ch++) {
        for (sb = 0; sb < s->nsubbands; sb++) {
            float *samples = s->time_samples[ch][sb];

            if (s->ch_pres[ch] & (1U << sb))
                continue;   // Skip allocated subband

            if (sb < 2) {
                // The first two subbands are always zero
                memset(samples, 0, DCA_LBR_TIME_SAMPLES * sizeof(float));
            } else if (sb < 10) {
                for (i = 0; i < DCA_LBR_TIME_SAMPLES; i++)
                    samples[i] = lbr_rand(s, sb);
            } else {
                for (i = 0; i < DCA_LBR_TIME_SAMPLES / 8; i++, samples += 8) {
                    float accum[8] = { 0 };

                    // Modulate by subbands 2-5 in blocks of 8
                    for (k = 2; k < 6; k++) {
                        float *other = &s->time_samples[ch][k][i * 8];
                        for (j = 0; j < 8; j++)
                            accum[j] += fabs(other[j]);
                    }

                    for (j = 0; j < 8; j++)
                        samples[j] = (accum[j] * 0.25f + 0.5f) * lbr_rand(s, sb);
                }
            }
        }
    }
}

static void predict(float *samples, const float *coeff, int nsamples)
{
    int i, j;

    for (i = 0; i < nsamples; i++) {
        float res = 0;
        for (j = 0; j < 8; j++)
            res += coeff[j] * samples[i - j - 1];
        samples[i] -= res;
    }
}

static void synth_lpc(DCALbrDecoder *s, int ch1, int ch2, int sb)
{
    int f = s->framenum & 1;
    int ch;

    for (ch = ch1; ch <= ch2; ch++) {
        float *samples = s->time_samples[ch][sb];

        if (!(s->ch_pres[ch] & (1U << sb)))
            continue;

        if (sb < 2) {
            predict(samples,      s->lpc_coeff[f^1][ch][sb][1],  16);
            predict(samples + 16, s->lpc_coeff[f  ][ch][sb][0],  64);
            predict(samples + 80, s->lpc_coeff[f  ][ch][sb][1],  48);
        } else {
            predict(samples,      s->lpc_coeff[f^1][ch][sb][0],  16);
            predict(samples + 16, s->lpc_coeff[f  ][ch][sb][0], 112);
        }
    }
}

static void filter_ts(DCALbrDecoder *s, int ch1, int ch2)
{
    int i, j, sb, ch;

    for (sb = 0; sb < s->nsubbands; sb++) {
        // Scale factors
        for (ch = ch1; ch <= ch2; ch++) {
            float *samples = s->time_samples[ch][sb];
            uint8_t *hr_scf = s->high_res_scf[ch][sb];
            if (sb < 4) {
                for (i = 0; i < DCA_LBR_TIME_SAMPLES / 16; i++, samples += 16) {
                    unsigned int scf = hr_scf[i];
                    if (scf > AMP_MAX)
                        scf = AMP_MAX;
                    for (j = 0; j < 16; j++)
                        samples[j] *= ff_dca_quant_amp[scf];
                }
            } else {
                uint8_t *g2_scf = s->grid_2_scf[ch][ff_dca_scf_to_grid_2[sb]];
                for (i = 0; i < DCA_LBR_TIME_SAMPLES / 2; i++, samples += 2) {
                    unsigned int scf = hr_scf[i / 8] - g2_scf[i];
                    if (scf > AMP_MAX)
                        scf = AMP_MAX;
                    samples[0] *= ff_dca_quant_amp[scf];
                    samples[1] *= ff_dca_quant_amp[scf];
                }
            }
        }

        // Mid-side stereo
        if (ch1 != ch2) {
            float *samples_l = s->time_samples[ch1][sb];
            float *samples_r = s->time_samples[ch2][sb];
            int ch2_pres = s->ch_pres[ch2] & (1U << sb);

            for (i = 0; i < DCA_LBR_TIME_SAMPLES / 16; i++) {
                int sbms = (s->sec_ch_sbms[ch1 / 2][sb] >> i) & 1;
                int lrms = (s->sec_ch_lrms[ch1 / 2][sb] >> i) & 1;

                if (sb >= s->min_mono_subband) {
                    if (lrms && ch2_pres) {
                        if (sbms) {
                            for (j = 0; j < 16; j++) {
                                float tmp = samples_l[j];
                                samples_l[j] =  samples_r[j];
                                samples_r[j] = -tmp;
                            }
                        } else {
                            for (j = 0; j < 16; j++) {
                                float tmp = samples_l[j];
                                samples_l[j] =  samples_r[j];
                                samples_r[j] =  tmp;
                            }
                        }
                    } else if (!ch2_pres) {
                        if (sbms && (s->part_stereo_pres & (1 << ch1))) {
                            for (j = 0; j < 16; j++)
                                samples_r[j] = -samples_l[j];
                        } else {
                            for (j = 0; j < 16; j++)
                                samples_r[j] =  samples_l[j];
                        }
                    }
                } else if (sbms && ch2_pres) {
                    for (j = 0; j < 16; j++) {
                        float tmp = samples_l[j];
                        samples_l[j] = (tmp + samples_r[j]) * 0.5f;
                        samples_r[j] = (tmp - samples_r[j]) * 0.5f;
                    }
                }

                samples_l += 16;
                samples_r += 16;
            }
        }

        // Inverse prediction
        if (sb < 3)
            synth_lpc(s, ch1, ch2, sb);
    }
}

/**
 * Modulate by interpolated partial stereo coefficients
 */
static void decode_part_stereo(DCALbrDecoder *s, int ch1, int ch2)
{
    int i, ch, sb, sf;

    for (ch = ch1; ch <= ch2; ch++) {
        for (sb = s->min_mono_subband; sb < s->nsubbands; sb++) {
            uint8_t *pt_st = s->part_stereo[ch][(sb - s->min_mono_subband) / 4];
            float *samples = s->time_samples[ch][sb];

            if (s->ch_pres[ch2] & (1U << sb))
                continue;

            for (sf = 1; sf <= 4; sf++, samples += 32) {
                float prev = ff_dca_st_coeff[pt_st[sf - 1]];
                float next = ff_dca_st_coeff[pt_st[sf    ]];

                for (i = 0; i < 32; i++)
                    samples[i] *= (32 - i) * prev + i * next;
            }
        }
    }
}

/**
 * Synthesise tones in the given group for the given tonal subframe
 */
static void synth_tones(DCALbrDecoder *s, int ch, float *values,
                        int group, int group_sf, int synth_idx)
{
    int i, start, count;

    if (synth_idx < 0)
        return;

    start =  s->tonal_bounds[group][group_sf][0];
    count = (s->tonal_bounds[group][group_sf][1] - start) & (DCA_LBR_TONES - 1);

    for (i = 0; i < count; i++) {
        DCALbrTone *t = &s->tones[(start + i) & (DCA_LBR_TONES - 1)];

        if (t->amp[ch]) {
            float amp = ff_dca_synth_env[synth_idx] * ff_dca_quant_amp[t->amp[ch]];
            float c = amp * cos_tab[(t->phs[ch]     ) & 255];
            float s = amp * cos_tab[(t->phs[ch] + 64) & 255];
            const float *cf = ff_dca_corr_cf[t->f_delt];
            int x_freq = t->x_freq;

            switch (x_freq) {
            case 0:
                goto p0;
            case 1:
                values[3] += cf[0] * -s;
                values[2] += cf[1] *  c;
                values[1] += cf[2] *  s;
                values[0] += cf[3] * -c;
                goto p1;
            case 2:
                values[2] += cf[0] * -s;
                values[1] += cf[1] *  c;
                values[0] += cf[2] *  s;
                goto p2;
            case 3:
                values[1] += cf[0] * -s;
                values[0] += cf[1] *  c;
                goto p3;
            case 4:
                values[0] += cf[0] * -s;
                goto p4;
            }

            values[x_freq - 5] += cf[ 0] * -s;
        p4: values[x_freq - 4] += cf[ 1] *  c;
        p3: values[x_freq - 3] += cf[ 2] *  s;
        p2: values[x_freq - 2] += cf[ 3] * -c;
        p1: values[x_freq - 1] += cf[ 4] * -s;
        p0: values[x_freq    ] += cf[ 5] *  c;
            values[x_freq + 1] += cf[ 6] *  s;
            values[x_freq + 2] += cf[ 7] * -c;
            values[x_freq + 3] += cf[ 8] * -s;
            values[x_freq + 4] += cf[ 9] *  c;
            values[x_freq + 5] += cf[10] *  s;
        }

        t->phs[ch] += t->ph_rot;
    }
}

/**
 * Synthesise all tones in all groups for the given residual subframe
 */
static void base_func_synth(DCALbrDecoder *s, int ch, float *values, int sf)
{
    int group;

    // Tonal vs residual shift is 22 subframes
    for (group = 0; group < 5; group++) {
        int group_sf = (s->framenum << group) + ((sf - 22) >> (5 - group));
        int synth_idx = ((((sf - 22) & 31) << group) & 31) + (1 << group) - 1;

        synth_tones(s, ch, values, group, (group_sf - 1) & 31, 30 - synth_idx);
        synth_tones(s, ch, values, group, (group_sf    ) & 31,      synth_idx);
    }
}

static void transform_channel(DCALbrDecoder *s, int ch, float *output)
{
    LOCAL_ALIGNED_32(float, values, [DCA_LBR_SUBBANDS    ], [4]);
    LOCAL_ALIGNED_32(float, result, [DCA_LBR_SUBBANDS * 2], [4]);
    int sf, sb, nsubbands = s->nsubbands, noutsubbands = 8 << s->freq_range;

    // Clear inactive subbands
    if (nsubbands < noutsubbands)
        memset(values[nsubbands], 0, (noutsubbands - nsubbands) * sizeof(values[0]));

    for (sf = 0; sf < DCA_LBR_TIME_SAMPLES / 4; sf++) {
        // Hybrid filterbank
        s->dcadsp->lbr_bank(values, s->time_samples[ch],
                            ff_dca_bank_coeff, sf * 4, nsubbands);

        base_func_synth(s, ch, values[0], sf);

        s->imdct.imdct_calc(&s->imdct, result[0], values[0]);

        // Long window and overlap-add
        s->fdsp->vector_fmul_add(output, result[0], s->window,
                                 s->history[ch], noutsubbands * 4);
        s->fdsp->vector_fmul_reverse(s->history[ch], result[noutsubbands],
                                     s->window, noutsubbands * 4);
        output += noutsubbands * 4;
    }

    // Update history for LPC and forward MDCT
    for (sb = 0; sb < nsubbands; sb++) {
        float *samples = s->time_samples[ch][sb] - DCA_LBR_TIME_HISTORY;
        memcpy(samples, samples + DCA_LBR_TIME_SAMPLES, DCA_LBR_TIME_HISTORY * sizeof(float));
    }
}

int ff_dca_lbr_filter_frame(DCALbrDecoder *s, AVFrame *frame)
{
    AVCodecContext *avctx = s->avctx;
    int i, ret, nchannels, ch_conf = (s->ch_mask & 0x7) - 1;
    const int8_t *reorder;
    uint64_t channel_mask = channel_layouts[ch_conf];

    nchannels = av_popcount64(channel_mask);
    avctx->sample_rate = s->sample_rate;
    avctx->sample_fmt = AV_SAMPLE_FMT_FLTP;
    avctx->bits_per_raw_sample = 0;
    avctx->profile = FF_PROFILE_DTS_EXPRESS;
    avctx->bit_rate = s->bit_rate_scaled;

    if (s->flags & LBR_FLAG_LFE_PRESENT) {
        channel_mask |= AV_CH_LOW_FREQUENCY;
        reorder = channel_reorder_lfe[ch_conf];
    } else {
        reorder = channel_reorder_nolfe[ch_conf];
    }

    av_channel_layout_uninit(&avctx->ch_layout);
    av_channel_layout_from_mask(&avctx->ch_layout, channel_mask);

    frame->nb_samples = 1024 << s->freq_range;
    if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
        return ret;

    // Filter fullband channels
    for (i = 0; i < (s->nchannels + 1) / 2; i++) {
        int ch1 = i * 2;
        int ch2 = FFMIN(ch1 + 1, s->nchannels - 1);

        decode_grid(s, ch1, ch2);

        random_ts(s, ch1, ch2);

        filter_ts(s, ch1, ch2);

        if (ch1 != ch2 && (s->part_stereo_pres & (1 << ch1)))
            decode_part_stereo(s, ch1, ch2);

        if (ch1 < nchannels)
            transform_channel(s, ch1, (float *)frame->extended_data[reorder[ch1]]);

        if (ch1 != ch2 && ch2 < nchannels)
            transform_channel(s, ch2, (float *)frame->extended_data[reorder[ch2]]);
    }

    // Interpolate LFE channel
    if (s->flags & LBR_FLAG_LFE_PRESENT) {
        s->dcadsp->lfe_iir((float *)frame->extended_data[lfe_index[ch_conf]],
                           s->lfe_data, ff_dca_lfe_iir,
                           s->lfe_history, 16 << s->freq_range);
    }

    if ((ret = ff_side_data_update_matrix_encoding(frame, AV_MATRIX_ENCODING_NONE)) < 0)
        return ret;

    return 0;
}

av_cold void ff_dca_lbr_flush(DCALbrDecoder *s)
{
    int ch, sb;

    if (!s->sample_rate)
        return;

    // Clear history
    memset(s->part_stereo, 16, sizeof(s->part_stereo));
    memset(s->lpc_coeff, 0, sizeof(s->lpc_coeff));
    memset(s->history, 0, sizeof(s->history));
    memset(s->tonal_bounds, 0, sizeof(s->tonal_bounds));
    memset(s->lfe_history, 0, sizeof(s->lfe_history));
    s->framenum = 0;
    s->ntones = 0;

    for (ch = 0; ch < s->nchannels; ch++) {
        for (sb = 0; sb < s->nsubbands; sb++) {
            float *samples = s->time_samples[ch][sb] - DCA_LBR_TIME_HISTORY;
            memset(samples, 0, DCA_LBR_TIME_HISTORY * sizeof(float));
        }
    }
}

av_cold int ff_dca_lbr_init(DCALbrDecoder *s)
{
    if (!(s->fdsp = avpriv_float_dsp_alloc(0)))
        return AVERROR(ENOMEM);

    s->lbr_rand = 1;
    return 0;
}

av_cold void ff_dca_lbr_close(DCALbrDecoder *s)
{
    s->sample_rate = 0;

    av_freep(&s->ts_buffer);
    s->ts_size = 0;

    av_freep(&s->fdsp);
    ff_mdct_end(&s->imdct);
}