libavcodec/takdec.c

   1 /*
   2  * TAK decoder
   3  * Copyright (c) 2012 Paul B Mahol
   4  *
   5  * This file is part of Libav.
   6  *
   7  * Libav is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * Libav is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with Libav; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 /**
  23  * @file
  24  * TAK (Tom's lossless Audio Kompressor) decoder
  25  * @author Paul B Mahol
  26  */
  27
  28 #include "libavutil/internal.h"
  29 #include "libavutil/samplefmt.h"
  30 #include "tak.h"
  31 #include "avcodec.h"
  32 #include "dsputil.h"
  33 #include "internal.h"
  34 #include "unary.h"
  35
  36 #define MAX_SUBFRAMES     8                         // max number of subframes per channel
  37 #define MAX_PREDICTORS  256
  38
  39 typedef struct MCDParam {
  40     int8_t present;                                 // decorrelation parameter availability for this channel
  41     int8_t index;                                   // index into array of decorrelation types
  42     int8_t chan1;
  43     int8_t chan2;
  44 } MCDParam;
  45
  46 typedef struct TAKDecContext {
  47     AVCodecContext *avctx;                          // parent AVCodecContext
  48     DSPContext      dsp;
  49     TAKStreamInfo   ti;
  50     GetBitContext   gb;                             // bitstream reader initialized to start at the current frame
  51
  52     int             uval;
  53     int             nb_samples;                     // number of samples in the current frame
  54     uint8_t        *decode_buffer;
  55     unsigned int    decode_buffer_size;
  56     int32_t        *decoded[TAK_MAX_CHANNELS];      // decoded samples for each channel
  57
  58     int8_t          lpc_mode[TAK_MAX_CHANNELS];
  59     int8_t          sample_shift[TAK_MAX_CHANNELS]; // shift applied to every sample in the channel
  60     int             subframe_scale;
  61
  62     int8_t          dmode;                          // channel decorrelation type in the current frame
  63
  64     MCDParam        mcdparams[TAK_MAX_CHANNELS];    // multichannel decorrelation parameters
  65
  66     int16_t        *residues;
  67     unsigned int    residues_buf_size;
  68 } TAKDecContext;
  69
  70 static const int8_t mc_dmodes[] = { 1, 3, 4, 6, };
  71
  72 static const uint16_t predictor_sizes[] = {
  73     4, 8, 12, 16, 24, 32, 48, 64, 80, 96, 128, 160, 192, 224, 256, 0,
  74 };
  75
  76 static const struct CParam {
  77     int init;
  78     int escape;
  79     int scale;
  80     int aescape;
  81     int bias;
  82 } xcodes[50] = {
  83     { 0x01, 0x0000001, 0x0000001, 0x0000003, 0x0000008 },
  84     { 0x02, 0x0000003, 0x0000001, 0x0000007, 0x0000006 },
  85     { 0x03, 0x0000005, 0x0000002, 0x000000E, 0x000000D },
  86     { 0x03, 0x0000003, 0x0000003, 0x000000D, 0x0000018 },
  87     { 0x04, 0x000000B, 0x0000004, 0x000001C, 0x0000019 },
  88     { 0x04, 0x0000006, 0x0000006, 0x000001A, 0x0000030 },
  89     { 0x05, 0x0000016, 0x0000008, 0x0000038, 0x0000032 },
  90     { 0x05, 0x000000C, 0x000000C, 0x0000034, 0x0000060 },
  91     { 0x06, 0x000002C, 0x0000010, 0x0000070, 0x0000064 },
  92     { 0x06, 0x0000018, 0x0000018, 0x0000068, 0x00000C0 },
  93     { 0x07, 0x0000058, 0x0000020, 0x00000E0, 0x00000C8 },
  94     { 0x07, 0x0000030, 0x0000030, 0x00000D0, 0x0000180 },
  95     { 0x08, 0x00000B0, 0x0000040, 0x00001C0, 0x0000190 },
  96     { 0x08, 0x0000060, 0x0000060, 0x00001A0, 0x0000300 },
  97     { 0x09, 0x0000160, 0x0000080, 0x0000380, 0x0000320 },
  98     { 0x09, 0x00000C0, 0x00000C0, 0x0000340, 0x0000600 },
  99     { 0x0A, 0x00002C0, 0x0000100, 0x0000700, 0x0000640 },
 100     { 0x0A, 0x0000180, 0x0000180, 0x0000680, 0x0000C00 },
 101     { 0x0B, 0x0000580, 0x0000200, 0x0000E00, 0x0000C80 },
 102     { 0x0B, 0x0000300, 0x0000300, 0x0000D00, 0x0001800 },
 103     { 0x0C, 0x0000B00, 0x0000400, 0x0001C00, 0x0001900 },
 104     { 0x0C, 0x0000600, 0x0000600, 0x0001A00, 0x0003000 },
 105     { 0x0D, 0x0001600, 0x0000800, 0x0003800, 0x0003200 },
 106     { 0x0D, 0x0000C00, 0x0000C00, 0x0003400, 0x0006000 },
 107     { 0x0E, 0x0002C00, 0x0001000, 0x0007000, 0x0006400 },
 108     { 0x0E, 0x0001800, 0x0001800, 0x0006800, 0x000C000 },
 109     { 0x0F, 0x0005800, 0x0002000, 0x000E000, 0x000C800 },
 110     { 0x0F, 0x0003000, 0x0003000, 0x000D000, 0x0018000 },
 111     { 0x10, 0x000B000, 0x0004000, 0x001C000, 0x0019000 },
 112     { 0x10, 0x0006000, 0x0006000, 0x001A000, 0x0030000 },
 113     { 0x11, 0x0016000, 0x0008000, 0x0038000, 0x0032000 },
 114     { 0x11, 0x000C000, 0x000C000, 0x0034000, 0x0060000 },
 115     { 0x12, 0x002C000, 0x0010000, 0x0070000, 0x0064000 },
 116     { 0x12, 0x0018000, 0x0018000, 0x0068000, 0x00C0000 },
 117     { 0x13, 0x0058000, 0x0020000, 0x00E0000, 0x00C8000 },
 118     { 0x13, 0x0030000, 0x0030000, 0x00D0000, 0x0180000 },
 119     { 0x14, 0x00B0000, 0x0040000, 0x01C0000, 0x0190000 },
 120     { 0x14, 0x0060000, 0x0060000, 0x01A0000, 0x0300000 },
 121     { 0x15, 0x0160000, 0x0080000, 0x0380000, 0x0320000 },
 122     { 0x15, 0x00C0000, 0x00C0000, 0x0340000, 0x0600000 },
 123     { 0x16, 0x02C0000, 0x0100000, 0x0700000, 0x0640000 },
 124     { 0x16, 0x0180000, 0x0180000, 0x0680000, 0x0C00000 },
 125     { 0x17, 0x0580000, 0x0200000, 0x0E00000, 0x0C80000 },
 126     { 0x17, 0x0300000, 0x0300000, 0x0D00000, 0x1800000 },
 127     { 0x18, 0x0B00000, 0x0400000, 0x1C00000, 0x1900000 },
 128     { 0x18, 0x0600000, 0x0600000, 0x1A00000, 0x3000000 },
 129     { 0x19, 0x1600000, 0x0800000, 0x3800000, 0x3200000 },
 130     { 0x19, 0x0C00000, 0x0C00000, 0x3400000, 0x6000000 },
 131     { 0x1A, 0x2C00000, 0x1000000, 0x7000000, 0x6400000 },
 132     { 0x1A, 0x1800000, 0x1800000, 0x6800000, 0xC000000 },
 133 };
 134
 135 static av_cold void tak_init_static_data(AVCodec *codec)
 136 {
 137     ff_tak_init_crc();
 138 }
 139
 140 static int set_bps_params(AVCodecContext *avctx)
 141 {
 142     switch (avctx->bits_per_coded_sample) {
 143     case 8:
 144         avctx->sample_fmt = AV_SAMPLE_FMT_U8P;
 145         break;
 146     case 16:
 147         avctx->sample_fmt = AV_SAMPLE_FMT_S16P;
 148         break;
 149     case 24:
 150         avctx->sample_fmt = AV_SAMPLE_FMT_S32P;
 151         break;
 152     default:
 153         av_log(avctx, AV_LOG_ERROR, "unsupported bits per sample: %d\n",
 154                avctx->bits_per_coded_sample);
 155         return AVERROR_INVALIDDATA;
 156     }
 157     avctx->bits_per_raw_sample = avctx->bits_per_coded_sample;
 158
 159     return 0;
 160 }
 161
 162 static void set_sample_rate_params(AVCodecContext *avctx)
 163 {
 164     TAKDecContext *s  = avctx->priv_data;
 165     int shift         = 3 - (avctx->sample_rate / 11025);
 166     shift             = FFMAX(0, shift);
 167     s->uval           = FFALIGN(avctx->sample_rate + 511 >> 9, 4) << shift;
 168     s->subframe_scale = FFALIGN(avctx->sample_rate + 511 >> 9, 4) << 1;
 169 }
 170
 171 static av_cold int tak_decode_init(AVCodecContext *avctx)
 172 {
 173     TAKDecContext *s = avctx->priv_data;
 174
 175     ff_dsputil_init(&s->dsp, avctx);
 176
 177     s->avctx = avctx;
 178
 179     set_sample_rate_params(avctx);
 180
 181     return set_bps_params(avctx);
 182 }
 183
 184 static void decode_lpc(int32_t *coeffs, int mode, int length)
 185 {
 186     int i;
 187
 188     if (length < 2)
 189         return;
 190
 191     if (mode == 1) {
 192         int a1 = *coeffs++;
 193         for (i = 0; i < length - 1 >> 1; i++) {
 194             *coeffs   += a1;
 195             coeffs[1] += *coeffs;
 196             a1         = coeffs[1];
 197             coeffs    += 2;
 198         }
 199         if (length - 1 & 1)
 200             *coeffs += a1;
 201     } else if (mode == 2) {
 202         int a1    = coeffs[1];
 203         int a2    = a1 + *coeffs;
 204         coeffs[1] = a2;
 205         if (length > 2) {
 206             coeffs += 2;
 207             for (i = 0; i < length - 2 >> 1; i++) {
 208                 int a3    = *coeffs + a1;
 209                 int a4    = a3 + a2;
 210                 *coeffs   = a4;
 211                 a1        = coeffs[1] + a3;
 212                 a2        = a1 + a4;
 213                 coeffs[1] = a2;
 214                 coeffs   += 2;
 215             }
 216             if (length & 1)
 217                 *coeffs += a1 + a2;
 218         }
 219     } else if (mode == 3) {
 220         int a1    = coeffs[1];
 221         int a2    = a1 + *coeffs;
 222         coeffs[1] = a2;
 223         if (length > 2) {
 224             int a3  = coeffs[2];
 225             int a4  = a3 + a1;
 226             int a5  = a4 + a2;
 227             coeffs += 3;
 228             for (i = 0; i < length - 3; i++) {
 229                 a3     += *coeffs;
 230                 a4     += a3;
 231                 a5     += a4;
 232                 *coeffs = a5;
 233                 coeffs++;
 234             }
 235         }
 236     }
 237 }
 238
 239 static int decode_segment(GetBitContext *gb, int mode, int32_t *decoded,
 240                           int len)
 241 {
 242     struct CParam code;
 243     int i;
 244
 245     if (!mode) {
 246         memset(decoded, 0, len * sizeof(*decoded));
 247         return 0;
 248     }
 249
 250     if (mode > FF_ARRAY_ELEMS(xcodes))
 251         return AVERROR_INVALIDDATA;
 252     code = xcodes[mode - 1];
 253
 254     for (i = 0; i < len; i++) {
 255         int x = get_bits_long(gb, code.init);
 256         if (x >= code.escape && get_bits1(gb)) {
 257             x |= 1 << code.init;
 258             if (x >= code.aescape) {
 259                 int scale = get_unary(gb, 1, 9);
 260                 if (scale == 9) {
 261                     int scale_bits = get_bits(gb, 3);
 262                     if (scale_bits > 0) {
 263                         if (scale_bits == 7) {
 264                             scale_bits += get_bits(gb, 5);
 265                             if (scale_bits > 29)
 266                                 return AVERROR_INVALIDDATA;
 267                         }
 268                         scale = get_bits_long(gb, scale_bits) + 1;
 269                         x    += code.scale * scale;
 270                     }
 271                     x += code.bias;
 272                 } else
 273                     x += code.scale * scale - code.escape;
 274             } else
 275                 x -= code.escape;
 276         }
 277         decoded[i] = (x >> 1) ^ -(x & 1);
 278     }
 279
 280     return 0;
 281 }
 282
 283 static int decode_residues(TAKDecContext *s, int32_t *decoded, int length)
 284 {
 285     GetBitContext *gb = &s->gb;
 286     int i, mode, ret;
 287
 288     if (length > s->nb_samples)
 289         return AVERROR_INVALIDDATA;
 290
 291     if (get_bits1(gb)) {
 292         int wlength, rval;
 293         int coding_mode[128];
 294
 295         wlength = length / s->uval;
 296
 297         rval = length - (wlength * s->uval);
 298
 299         if (rval < s->uval / 2)
 300             rval += s->uval;
 301         else
 302             wlength++;
 303
 304         if (wlength <= 1 || wlength > 128)
 305             return AVERROR_INVALIDDATA;
 306
 307         coding_mode[0] = mode = get_bits(gb, 6);
 308
 309         for (i = 1; i < wlength; i++) {
 310             int c = get_unary(gb, 1, 6);
 311
 312             switch (c) {
 313             case 6:
 314                 mode = get_bits(gb, 6);
 315                 break;
 316             case 5:
 317             case 4:
 318             case 3: {
 319                 /* mode += sign ? (1 - c) : (c - 1) */
 320                 int sign = get_bits1(gb);
 321                 mode    += (-sign ^ (c - 1)) + sign;
 322                 break;
 323             }
 324             case 2:
 325                 mode++;
 326                 break;
 327             case 1:
 328                 mode--;
 329                 break;
 330             }
 331             coding_mode[i] = mode;
 332         }
 333
 334         i = 0;
 335         while (i < wlength) {
 336             int len = 0;
 337
 338             mode = coding_mode[i];
 339             do {
 340                 if (i >= wlength - 1)
 341                     len += rval;
 342                 else
 343                     len += s->uval;
 344                 i++;
 345
 346                 if (i == wlength)
 347                     break;
 348             } while (coding_mode[i] == mode);
 349
 350             if ((ret = decode_segment(gb, mode, decoded, len)) < 0)
 351                 return ret;
 352             decoded += len;
 353         }
 354     } else {
 355         mode = get_bits(gb, 6);
 356         if ((ret = decode_segment(gb, mode, decoded, length)) < 0)
 357             return ret;
 358     }
 359
 360     return 0;
 361 }
 362
 363 static int get_bits_esc4(GetBitContext *gb)
 364 {
 365     if (get_bits1(gb))
 366         return get_bits(gb, 4) + 1;
 367     else
 368         return 0;
 369 }
 370
 371 static void decode_filter_coeffs(TAKDecContext *s, int filter_order, int size,
 372                                  int filter_quant, int16_t *filter)
 373 {
 374     GetBitContext *gb = &s->gb;
 375     int i, j, a, b;
 376     int filter_tmp[MAX_PREDICTORS];
 377     int16_t predictors[MAX_PREDICTORS];
 378
 379     predictors[0] = get_sbits(gb, 10);
 380     predictors[1] = get_sbits(gb, 10);
 381     predictors[2] = get_sbits(gb, size) << (10 - size);
 382     predictors[3] = get_sbits(gb, size) << (10 - size);
 383     if (filter_order > 4) {
 384         int av_uninit(code_size);
 385         int code_size_base = size - get_bits1(gb);
 386
 387         for (i = 4; i < filter_order; i++) {
 388             if (!(i & 3))
 389                 code_size = code_size_base - get_bits(gb, 2);
 390             predictors[i] = get_sbits(gb, code_size) << (10 - size);
 391         }
 392     }
 393
 394     filter_tmp[0] = predictors[0] << 6;
 395     for (i = 1; i < filter_order; i++) {
 396         int *p1 = &filter_tmp[0];
 397         int *p2 = &filter_tmp[i - 1];
 398
 399         for (j = 0; j < (i + 1) / 2; j++) {
 400             int tmp = *p1 + (predictors[i] * *p2 + 256 >> 9);
 401             *p2     = *p2 + (predictors[i] * *p1 + 256 >> 9);
 402             *p1     = tmp;
 403             p1++;
 404             p2--;
 405         }
 406
 407         filter_tmp[i] = predictors[i] << 6;
 408     }
 409
 410     a = 1 << (32 - (15 - filter_quant));
 411     b = 1 << ((15 - filter_quant) - 1);
 412     for (i = 0, j = filter_order - 1; i < filter_order / 2; i++, j--) {
 413         filter[j] = a - ((filter_tmp[i] + b) >> (15 - filter_quant));
 414         filter[i] = a - ((filter_tmp[j] + b) >> (15 - filter_quant));
 415     }
 416 }
 417
 418 static int decode_subframe(TAKDecContext *s, int32_t *decoded,
 419                            int subframe_size, int prev_subframe_size)
 420 {
 421     LOCAL_ALIGNED_16(int16_t, filter, [MAX_PREDICTORS]);
 422     GetBitContext *gb = &s->gb;
 423     int i, ret;
 424     int dshift, size, filter_quant, filter_order;
 425
 426     memset(filter, 0, MAX_PREDICTORS * sizeof(*filter));
 427
 428     if (!get_bits1(gb))
 429         return decode_residues(s, decoded, subframe_size);
 430
 431     filter_order = predictor_sizes[get_bits(gb, 4)];
 432
 433     if (prev_subframe_size > 0 && get_bits1(gb)) {
 434         if (filter_order > prev_subframe_size)
 435             return AVERROR_INVALIDDATA;
 436
 437         decoded       -= filter_order;
 438         subframe_size += filter_order;
 439
 440         if (filter_order > subframe_size)
 441             return AVERROR_INVALIDDATA;
 442     } else {
 443         int lpc_mode;
 444
 445         if (filter_order > subframe_size)
 446             return AVERROR_INVALIDDATA;
 447
 448         lpc_mode = get_bits(gb, 2);
 449         if (lpc_mode > 2)
 450             return AVERROR_INVALIDDATA;
 451
 452         if ((ret = decode_residues(s, decoded, filter_order)) < 0)
 453             return ret;
 454
 455         if (lpc_mode)
 456             decode_lpc(decoded, lpc_mode, filter_order);
 457     }
 458
 459     dshift = get_bits_esc4(gb);
 460     size   = get_bits1(gb) + 6;
 461
 462     filter_quant = 10;
 463     if (get_bits1(gb)) {
 464         filter_quant -= get_bits(gb, 3) + 1;
 465         if (filter_quant < 3)
 466             return AVERROR_INVALIDDATA;
 467     }
 468
 469     decode_filter_coeffs(s, filter_order, size, filter_quant, filter);
 470
 471     if ((ret = decode_residues(s, &decoded[filter_order],
 472                                subframe_size - filter_order)) < 0)
 473         return ret;
 474
 475     av_fast_malloc(&s->residues, &s->residues_buf_size,
 476                    FFALIGN(subframe_size + 16, 16) * sizeof(*s->residues));
 477     if (!s->residues)
 478         return AVERROR(ENOMEM);
 479     memset(s->residues, 0, s->residues_buf_size);
 480
 481     for (i = 0; i < filter_order; i++)
 482         s->residues[i] = *decoded++ >> dshift;
 483
 484     for (i = 0; i < subframe_size - filter_order; i++) {
 485         int v = 1 << (filter_quant - 1);
 486
 487         v += s->dsp.scalarproduct_int16(&s->residues[i], filter,
 488                                         FFALIGN(filter_order, 16));
 489
 490         v = (av_clip(v >> filter_quant, -8192, 8191) << dshift) - *decoded;
 491         *decoded++ = v;
 492         s->residues[filter_order + i] = v >> dshift;
 493     }
 494
 495     emms_c();
 496
 497     return 0;
 498 }
 499
 500 static int decode_channel(TAKDecContext *s, int chan)
 501 {
 502     AVCodecContext *avctx = s->avctx;
 503     GetBitContext *gb     = &s->gb;
 504     int32_t *decoded      = s->decoded[chan];
 505     int left              = s->nb_samples - 1;
 506     int i, prev, ret, nb_subframes;
 507     int subframe_len[MAX_SUBFRAMES];
 508
 509     s->sample_shift[chan] = get_bits_esc4(gb);
 510     if (s->sample_shift[chan] >= avctx->bits_per_coded_sample)
 511         return AVERROR_INVALIDDATA;
 512
 513     /* NOTE: TAK 2.2.0 appears to set the sample value to 0 if
 514      *       bits_per_coded_sample - sample_shift is 1, but this produces
 515      *       non-bit-exact output. Reading the 1 bit using get_sbits() instead
 516      *       of skipping it produces bit-exact output. This has been reported
 517      *       to the TAK author. */
 518     *decoded++        = get_sbits(gb,
 519                                   avctx->bits_per_coded_sample -
 520                                   s->sample_shift[chan]);
 521     s->lpc_mode[chan] = get_bits(gb, 2);
 522     nb_subframes      = get_bits(gb, 3) + 1;
 523
 524     i = 0;
 525     if (nb_subframes > 1) {
 526         if (get_bits_left(gb) < (nb_subframes - 1) * 6)
 527             return AVERROR_INVALIDDATA;
 528
 529         prev = 0;
 530         for (; i < nb_subframes - 1; i++) {
 531             int subframe_end = get_bits(gb, 6) * s->subframe_scale;
 532             if (subframe_end <= prev)
 533                 return AVERROR_INVALIDDATA;
 534             subframe_len[i] = subframe_end - prev;
 535             left           -= subframe_len[i];
 536             prev            = subframe_end;
 537         }
 538
 539         if (left <= 0)
 540             return AVERROR_INVALIDDATA;
 541     }
 542     subframe_len[i] = left;
 543
 544     prev = 0;
 545     for (i = 0; i < nb_subframes; i++) {
 546         if ((ret = decode_subframe(s, decoded, subframe_len[i], prev)) < 0)
 547             return ret;
 548         decoded += subframe_len[i];
 549         prev     = subframe_len[i];
 550     }
 551
 552     return 0;
 553 }
 554
 555 static int decorrelate(TAKDecContext *s, int c1, int c2, int length)
 556 {
 557     GetBitContext *gb = &s->gb;
 558     int32_t *p1       = s->decoded[c1] + 1;
 559     int32_t *p2       = s->decoded[c2] + 1;
 560     int i;
 561     int dshift, dfactor;
 562
 563     switch (s->dmode) {
 564     case 1: /* left/side */
 565         for (i = 0; i < length; i++) {
 566             int32_t a = p1[i];
 567             int32_t b = p2[i];
 568             p2[i]     = a + b;
 569         }
 570         break;
 571     case 2: /* side/right */
 572         for (i = 0; i < length; i++) {
 573             int32_t a = p1[i];
 574             int32_t b = p2[i];
 575             p1[i]     = b - a;
 576         }
 577         break;
 578     case 3: /* side/mid */
 579         for (i = 0; i < length; i++) {
 580             int32_t a = p1[i];
 581             int32_t b = p2[i];
 582             a        -= b >> 1;
 583             p1[i]     = a;
 584             p2[i]     = a + b;
 585         }
 586         break;
 587     case 4: /* side/left with scale factor */
 588         FFSWAP(int32_t*, p1, p2);
 589     case 5: /* side/right with scale factor */
 590         dshift  = get_bits_esc4(gb);
 591         dfactor = get_sbits(gb, 10);
 592         for (i = 0; i < length; i++) {
 593             int32_t a = p1[i];
 594             int32_t b = p2[i];
 595             b         = dfactor * (b >> dshift) + 128 >> 8 << dshift;
 596             p1[i]     = b - a;
 597         }
 598         break;
 599     case 6:
 600         FFSWAP(int32_t*, p1, p2);
 601     case 7: {
 602         LOCAL_ALIGNED_16(int16_t, filter, [MAX_PREDICTORS]);
 603         int length2, order_half, filter_order, dval1, dval2;
 604         int av_uninit(code_size);
 605
 606         memset(filter, 0, MAX_PREDICTORS * sizeof(*filter));
 607
 608         if (length < 256)
 609             return AVERROR_INVALIDDATA;
 610
 611         dshift       = get_bits_esc4(gb);
 612         filter_order = 8 << get_bits1(gb);
 613         dval1        = get_bits1(gb);
 614         dval2        = get_bits1(gb);
 615
 616         for (i = 0; i < filter_order; i++) {
 617             if (!(i & 3))
 618                 code_size = 14 - get_bits(gb, 3);
 619             filter[i] = get_sbits(gb, code_size);
 620         }
 621
 622         order_half = filter_order / 2;
 623         length2    = length - (filter_order - 1);
 624
 625         /* decorrelate beginning samples */
 626         if (dval1) {
 627             for (i = 0; i < order_half; i++) {
 628                 int32_t a = p1[i];
 629                 int32_t b = p2[i];
 630                 p1[i]     = a + b;
 631             }
 632         }
 633
 634         /* decorrelate ending samples */
 635         if (dval2) {
 636             for (i = length2 + order_half; i < length; i++) {
 637                 int32_t a = p1[i];
 638                 int32_t b = p2[i];
 639                 p1[i]     = a + b;
 640             }
 641         }
 642
 643         av_fast_malloc(&s->residues, &s->residues_buf_size,
 644                        FFALIGN(length + 16, 16) * sizeof(*s->residues));
 645         if (!s->residues)
 646             return AVERROR(ENOMEM);
 647         memset(s->residues, 0, s->residues_buf_size);
 648
 649         for (i = 0; i < length; i++)
 650             s->residues[i] = p2[i] >> dshift;
 651
 652         p1 += order_half;
 653
 654         for (i = 0; i < length2; i++) {
 655             int v = 1 << 9;
 656
 657             v += s->dsp.scalarproduct_int16(&s->residues[i], filter,
 658                                             FFALIGN(filter_order, 16));
 659
 660             p1[i] = (av_clip(v >> 10, -8192, 8191) << dshift) - p1[i];
 661         }
 662
 663         emms_c();
 664         break;
 665     }
 666     }
 667
 668     return 0;
 669 }
 670
 671 static int tak_decode_frame(AVCodecContext *avctx, void *data,
 672                             int *got_frame_ptr, AVPacket *pkt)
 673 {
 674     TAKDecContext *s  = avctx->priv_data;
 675     AVFrame *frame    = data;
 676     GetBitContext *gb = &s->gb;
 677     int chan, i, ret, hsize;
 678
 679     if (pkt->size < TAK_MIN_FRAME_HEADER_BYTES)
 680         return AVERROR_INVALIDDATA;
 681
 682     init_get_bits(gb, pkt->data, pkt->size * 8);
 683
 684     if ((ret = ff_tak_decode_frame_header(avctx, gb, &s->ti, 0)) < 0)
 685         return ret;
 686
 687     if (s->ti.flags & TAK_FRAME_FLAG_HAS_METADATA) {
 688         av_log_missing_feature(avctx, "frame metadata", 1);
 689         return AVERROR_PATCHWELCOME;
 690     }
 691
 692     hsize = get_bits_count(gb) / 8;
 693     if (avctx->err_recognition & AV_EF_CRCCHECK) {
 694         if (ff_tak_check_crc(pkt->data, hsize)) {
 695             av_log(avctx, AV_LOG_ERROR, "CRC error\n");
 696             return AVERROR_INVALIDDATA;
 697         }
 698     }
 699
 700     if (s->ti.codec != TAK_CODEC_MONO_STEREO &&
 701         s->ti.codec != TAK_CODEC_MULTICHANNEL) {
 702         av_log(avctx, AV_LOG_ERROR, "unsupported codec: %d\n", s->ti.codec);
 703         return AVERROR_PATCHWELCOME;
 704     }
 705     if (s->ti.data_type) {
 706         av_log(avctx, AV_LOG_ERROR,
 707                "unsupported data type: %d\n", s->ti.data_type);
 708         return AVERROR_INVALIDDATA;
 709     }
 710     if (s->ti.codec == TAK_CODEC_MONO_STEREO && s->ti.channels > 2) {
 711         av_log(avctx, AV_LOG_ERROR,
 712                "invalid number of channels: %d\n", s->ti.channels);
 713         return AVERROR_INVALIDDATA;
 714     }
 715     if (s->ti.channels > 6) {
 716         av_log(avctx, AV_LOG_ERROR,
 717                "unsupported number of channels: %d\n", s->ti.channels);
 718         return AVERROR_INVALIDDATA;
 719     }
 720
 721     if (s->ti.frame_samples <= 0) {
 722         av_log(avctx, AV_LOG_ERROR, "unsupported/invalid number of samples\n");
 723         return AVERROR_INVALIDDATA;
 724     }
 725
 726     if (s->ti.bps != avctx->bits_per_coded_sample) {
 727         avctx->bits_per_coded_sample = s->ti.bps;
 728         if ((ret = set_bps_params(avctx)) < 0)
 729             return ret;
 730     }
 731     if (s->ti.sample_rate != avctx->sample_rate) {
 732         avctx->sample_rate = s->ti.sample_rate;
 733         set_sample_rate_params(avctx);
 734     }
 735     if (s->ti.ch_layout)
 736         avctx->channel_layout = s->ti.ch_layout;
 737     avctx->channels = s->ti.channels;
 738
 739     s->nb_samples = s->ti.last_frame_samples ? s->ti.last_frame_samples
 740                                              : s->ti.frame_samples;
 741
 742     frame->nb_samples = s->nb_samples;
 743     if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
 744         return ret;
 745
 746     if (avctx->bits_per_coded_sample <= 16) {
 747         int buf_size = av_samples_get_buffer_size(NULL, avctx->channels,
 748                                                   s->nb_samples,
 749                                                   AV_SAMPLE_FMT_S32P, 0);
 750         av_fast_malloc(&s->decode_buffer, &s->decode_buffer_size, buf_size);
 751         if (!s->decode_buffer)
 752             return AVERROR(ENOMEM);
 753         ret = av_samples_fill_arrays((uint8_t **)s->decoded, NULL,
 754                                      s->decode_buffer, avctx->channels,
 755                                      s->nb_samples, AV_SAMPLE_FMT_S32P, 0);
 756         if (ret < 0)
 757             return ret;
 758     } else {
 759         for (chan = 0; chan < avctx->channels; chan++)
 760             s->decoded[chan] = (int32_t *)frame->extended_data[chan];
 761     }
 762
 763     if (s->nb_samples < 16) {
 764         for (chan = 0; chan < avctx->channels; chan++) {
 765             int32_t *decoded = s->decoded[chan];
 766             for (i = 0; i < s->nb_samples; i++)
 767                 decoded[i] = get_sbits(gb, avctx->bits_per_coded_sample);
 768         }
 769     } else {
 770         if (s->ti.codec == TAK_CODEC_MONO_STEREO) {
 771             for (chan = 0; chan < avctx->channels; chan++)
 772                 if (ret = decode_channel(s, chan))
 773                     return ret;
 774
 775             if (avctx->channels == 2) {
 776                 if (get_bits1(gb)) {
 777                     // some kind of subframe length, but it seems to be unused
 778                     skip_bits(gb, 6);
 779                 }
 780
 781                 s->dmode = get_bits(gb, 3);
 782                 if (ret = decorrelate(s, 0, 1, s->nb_samples - 1))
 783                     return ret;
 784             }
 785         } else if (s->ti.codec == TAK_CODEC_MULTICHANNEL) {
 786             if (get_bits1(gb)) {
 787                 int ch_mask = 0;
 788
 789                 chan = get_bits(gb, 4) + 1;
 790                 if (chan > avctx->channels)
 791                     return AVERROR_INVALIDDATA;
 792
 793                 for (i = 0; i < chan; i++) {
 794                     int nbit = get_bits(gb, 4);
 795
 796                     if (nbit >= avctx->channels)
 797                         return AVERROR_INVALIDDATA;
 798
 799                     if (ch_mask & 1 << nbit)
 800                         return AVERROR_INVALIDDATA;
 801
 802                     s->mcdparams[i].present = get_bits1(gb);
 803                     if (s->mcdparams[i].present) {
 804                         s->mcdparams[i].index = get_bits(gb, 2);
 805                         s->mcdparams[i].chan2 = get_bits(gb, 4);
 806                         if (s->mcdparams[i].index == 1) {
 807                             if ((nbit == s->mcdparams[i].chan2) ||
 808                                 (ch_mask & 1 << s->mcdparams[i].chan2))
 809                                 return AVERROR_INVALIDDATA;
 810
 811                             ch_mask |= 1 << s->mcdparams[i].chan2;
 812                         } else if (!(ch_mask & 1 << s->mcdparams[i].chan2)) {
 813                             return AVERROR_INVALIDDATA;
 814                         }
 815                     }
 816                     s->mcdparams[i].chan1 = nbit;
 817
 818                     ch_mask |= 1 << nbit;
 819                 }
 820             } else {
 821                 chan = avctx->channels;
 822                 for (i = 0; i < chan; i++) {
 823                     s->mcdparams[i].present = 0;
 824                     s->mcdparams[i].chan1   = i;
 825                 }
 826             }
 827
 828             for (i = 0; i < chan; i++) {
 829                 if (s->mcdparams[i].present && s->mcdparams[i].index == 1)
 830                     if (ret = decode_channel(s, s->mcdparams[i].chan2))
 831                         return ret;
 832
 833                 if (ret = decode_channel(s, s->mcdparams[i].chan1))
 834                     return ret;
 835
 836                 if (s->mcdparams[i].present) {
 837                     s->dmode = mc_dmodes[s->mcdparams[i].index];
 838                     if (ret = decorrelate(s,
 839                                           s->mcdparams[i].chan2,
 840                                           s->mcdparams[i].chan1,
 841                                           s->nb_samples - 1))
 842                         return ret;
 843                 }
 844             }
 845         }
 846
 847         for (chan = 0; chan < avctx->channels; chan++) {
 848             int32_t *decoded = s->decoded[chan];
 849
 850             if (s->lpc_mode[chan])
 851                 decode_lpc(decoded, s->lpc_mode[chan], s->nb_samples);
 852
 853             if (s->sample_shift[chan] > 0)
 854                 for (i = 0; i < s->nb_samples; i++)
 855                     decoded[i] <<= s->sample_shift[chan];
 856         }
 857     }
 858
 859     align_get_bits(gb);
 860     skip_bits(gb, 24);
 861     if (get_bits_left(gb) < 0)
 862         av_log(avctx, AV_LOG_DEBUG, "overread\n");
 863     else if (get_bits_left(gb) > 0)
 864         av_log(avctx, AV_LOG_DEBUG, "underread\n");
 865
 866     if (avctx->err_recognition & AV_EF_CRCCHECK) {
 867         if (ff_tak_check_crc(pkt->data + hsize,
 868                              get_bits_count(gb) / 8 - hsize)) {
 869             av_log(avctx, AV_LOG_ERROR, "CRC error\n");
 870             return AVERROR_INVALIDDATA;
 871         }
 872     }
 873
 874     /* convert to output buffer */
 875     switch (avctx->sample_fmt) {
 876     case AV_SAMPLE_FMT_U8P:
 877         for (chan = 0; chan < avctx->channels; chan++) {
 878             uint8_t *samples = (uint8_t *)frame->extended_data[chan];
 879             int32_t *decoded = s->decoded[chan];
 880             for (i = 0; i < s->nb_samples; i++)
 881                 samples[i] = decoded[i] + 0x80;
 882         }
 883         break;
 884     case AV_SAMPLE_FMT_S16P:
 885         for (chan = 0; chan < avctx->channels; chan++) {
 886             int16_t *samples = (int16_t *)frame->extended_data[chan];
 887             int32_t *decoded = s->decoded[chan];
 888             for (i = 0; i < s->nb_samples; i++)
 889                 samples[i] = decoded[i];
 890         }
 891         break;
 892     case AV_SAMPLE_FMT_S32P:
 893         for (chan = 0; chan < avctx->channels; chan++) {
 894             int32_t *samples = (int32_t *)frame->extended_data[chan];
 895             for (i = 0; i < s->nb_samples; i++)
 896                 samples[i] <<= 8;
 897         }
 898         break;
 899     }
 900
 901     *got_frame_ptr = 1;
 902
 903     return pkt->size;
 904 }
 905
 906 static av_cold int tak_decode_close(AVCodecContext *avctx)
 907 {
 908     TAKDecContext *s = avctx->priv_data;
 909
 910     av_freep(&s->decode_buffer);
 911     av_freep(&s->residues);
 912
 913     return 0;
 914 }
 915
 916 AVCodec ff_tak_decoder = {
 917     .name             = "tak",
 918     .type             = AVMEDIA_TYPE_AUDIO,
 919     .id               = AV_CODEC_ID_TAK,
 920     .priv_data_size   = sizeof(TAKDecContext),
 921     .init             = tak_decode_init,
 922     .init_static_data = tak_init_static_data,
 923     .close            = tak_decode_close,
 924     .decode           = tak_decode_frame,
 925     .capabilities     = CODEC_CAP_DR1,
 926     .long_name        = NULL_IF_CONFIG_SMALL("TAK (Tom's lossless Audio Kompressor)"),
 927     .sample_fmts      = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_U8P,
 928                                                         AV_SAMPLE_FMT_S16P,
 929                                                         AV_SAMPLE_FMT_S32P,
 930                                                         AV_SAMPLE_FMT_NONE },
 931 };