wmadec_filter.c

   1 /*
   2  * WMA compatible decoder
   3  *
   4  * Extracted 2009 from the mplayer source code 2009-02-10.
   5  *
   6  * Copyright (c) 2002 The FFmpeg Project
   7  *
   8  * Licensed under the GNU Lesser General Public License.
   9  * For licencing details see COPYING.LIB.
  10  */
  11
  12 /** * \file wmadec_filter.c paraslash's WMA decoder.  */
  13
  14 /*
  15  * This decoder handles Microsoft Windows Media Audio data version 2.
  16  */
  17
  18 #define _XOPEN_SOURCE 600
  19
  20 #include <sys/time.h>
  21 #include <inttypes.h>
  22 #include <math.h>
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <math.h>
  26 #include <string.h>
  27 #include <regex.h>
  28
  29 #include "para.h"
  30 #include "error.h"
  31 #include "list.h"
  32 #include "ggo.h"
  33 #include "string.h"
  34 #include "sched.h"
  35 #include "filter.h"
  36 #include "bitstream.h"
  37 #include "mdct.h"
  38 #include "wma.h"
  39 #include "wmadata.h"
  40
  41
  42 /* size of blocks */
  43 #define BLOCK_MIN_BITS 7
  44 #define BLOCK_MAX_BITS 11
  45 #define BLOCK_MAX_SIZE (1 << BLOCK_MAX_BITS)
  46
  47 #define BLOCK_NB_SIZES (BLOCK_MAX_BITS - BLOCK_MIN_BITS + 1)
  48
  49 /* XXX: find exact max size */
  50 #define HIGH_BAND_MAX_SIZE 16
  51
  52 /* XXX: is it a suitable value ? */
  53 #define MAX_CODED_SUPERFRAME_SIZE 16384
  54
  55 #define MAX_CHANNELS 2
  56
  57 #define NOISE_TAB_SIZE 8192
  58
  59 #define LSP_POW_BITS 7
  60
  61 struct private_wmadec_data {
  62         struct asf_header_info ahi;
  63         struct getbit_context gb;
  64         int use_bit_reservoir;
  65         int use_variable_block_len;
  66         int use_exp_vlc;        ///< exponent coding: 0 = lsp, 1 = vlc + delta
  67         int use_noise_coding;   ///< true if perceptual noise is added
  68         int byte_offset_bits;
  69         struct vlc exp_vlc;
  70         int exponent_sizes[BLOCK_NB_SIZES];
  71         uint16_t exponent_bands[BLOCK_NB_SIZES][25];
  72         int high_band_start[BLOCK_NB_SIZES];    ///< index of first coef in high band
  73         int coefs_start;        ///< first coded coef
  74         int coefs_end[BLOCK_NB_SIZES];  ///< max number of coded coefficients
  75         int exponent_high_sizes[BLOCK_NB_SIZES];
  76         int exponent_high_bands[BLOCK_NB_SIZES][HIGH_BAND_MAX_SIZE];
  77         struct vlc hgain_vlc;
  78
  79         /* coded values in high bands */
  80         int high_band_coded[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
  81         int high_band_values[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
  82
  83         /* there are two possible tables for spectral coefficients */
  84         struct vlc coef_vlc[2];
  85         uint16_t *run_table[2];
  86         uint16_t *level_table[2];
  87         uint16_t *int_table[2];
  88         const struct coef_vlc_table *coef_vlcs[2];
  89         /* frame info */
  90         int frame_len;          ///< frame length in samples
  91         int frame_len_bits;     ///< frame_len = 1 << frame_len_bits
  92         int nb_block_sizes;     ///< number of block sizes
  93         /* block info */
  94         int reset_block_lengths;
  95         int block_len_bits;     ///< log2 of current block length
  96         int next_block_len_bits;        ///< log2 of next block length
  97         int prev_block_len_bits;        ///< log2 of prev block length
  98         int block_len;          ///< block length in samples
  99         int block_num;          ///< block number in current frame
 100         int block_pos;          ///< current position in frame
 101         uint8_t ms_stereo;      ///< true if mid/side stereo mode
 102         uint8_t channel_coded[MAX_CHANNELS];    ///< true if channel is coded
 103         int exponents_bsize[MAX_CHANNELS];      ///< log2 ratio frame/exp. length
 104         float exponents[MAX_CHANNELS][BLOCK_MAX_SIZE];
 105         float max_exponent[MAX_CHANNELS];
 106         int16_t coefs1[MAX_CHANNELS][BLOCK_MAX_SIZE];
 107         float coefs[MAX_CHANNELS][BLOCK_MAX_SIZE];
 108         float output[BLOCK_MAX_SIZE * 2];
 109         struct mdct_context *mdct_ctx[BLOCK_NB_SIZES];
 110         float *windows[BLOCK_NB_SIZES];
 111         /* output buffer for one frame and the last for IMDCT windowing */
 112         float frame_out[MAX_CHANNELS][BLOCK_MAX_SIZE * 2];
 113         /* last frame info */
 114         uint8_t last_superframe[MAX_CODED_SUPERFRAME_SIZE + 4]; /* padding added */
 115         int last_bitoffset;
 116         int last_superframe_len;
 117         float noise_table[NOISE_TAB_SIZE];
 118         int noise_index;
 119         float noise_mult;       /* XXX: suppress that and integrate it in the noise array */
 120         /* lsp_to_curve tables */
 121         float lsp_cos_table[BLOCK_MAX_SIZE];
 122         float lsp_pow_e_table[256];
 123         float lsp_pow_m_table1[(1 << LSP_POW_BITS)];
 124         float lsp_pow_m_table2[(1 << LSP_POW_BITS)];
 125 };
 126
 127 #define EXPVLCBITS 8
 128 #define EXPMAX ((19+EXPVLCBITS-1)/EXPVLCBITS)
 129
 130 #define HGAINVLCBITS 9
 131 #define HGAINMAX ((13+HGAINVLCBITS-1)/HGAINVLCBITS)
 132
 133 #define VLCBITS 9
 134 #define VLCMAX ((22+VLCBITS-1)/VLCBITS)
 135
 136 static int wmadec_cleanup(struct private_wmadec_data *s)
 137 {
 138         int i;
 139
 140         for (i = 0; i < s->nb_block_sizes; i++)
 141                 mdct_end(s->mdct_ctx[i]);
 142
 143         if (s->use_exp_vlc)
 144                 free_vlc(&s->exp_vlc);
 145         if (s->use_noise_coding)
 146                 free_vlc(&s->hgain_vlc);
 147         for (i = 0; i < 2; i++) {
 148                 free_vlc(&s->coef_vlc[i]);
 149                 free(s->run_table[i]);
 150                 free(s->level_table[i]);
 151                 free(s->int_table[i]);
 152         }
 153         return 0;
 154 }
 155
 156 /* XXX: use same run/length optimization as mpeg decoders */
 157 //FIXME maybe split decode / encode or pass flag
 158 static void init_coef_vlc(struct vlc *vlc, uint16_t **prun_table,
 159                 uint16_t **plevel_table, uint16_t **pint_table,
 160                 const struct coef_vlc_table *vlc_table)
 161 {
 162         int n = vlc_table->n;
 163         const uint8_t *table_bits = vlc_table->huffbits;
 164         const uint32_t *table_codes = vlc_table->huffcodes;
 165         const uint16_t *levels_table = vlc_table->levels;
 166         uint16_t *run_table, *level_table, *int_table;
 167         int i, l, j, k, level;
 168
 169         init_vlc(vlc, VLCBITS, n, table_bits, 1, 1, table_codes, 4, 4);
 170
 171         run_table = para_malloc(n * sizeof (uint16_t));
 172         level_table = para_malloc(n * sizeof (uint16_t));
 173         int_table = para_malloc(n * sizeof (uint16_t));
 174         i = 2;
 175         level = 1;
 176         k = 0;
 177         while (i < n) {
 178                 int_table[k] = i;
 179                 l = levels_table[k++];
 180                 for (j = 0; j < l; j++) {
 181                         run_table[i] = j;
 182                         level_table[i] = level;
 183                         i++;
 184                 }
 185                 level++;
 186         }
 187         *prun_table = run_table;
 188         *plevel_table = level_table;
 189         *pint_table = int_table;
 190 }
 191
 192 /* compute the scale factor band sizes for each MDCT block size */
 193 static void compute_scale_factor_band_sizes(struct private_wmadec_data *s,
 194         float high_freq)
 195 {
 196         struct asf_header_info *ahi = &s->ahi;
 197         int a, b, pos, lpos, k, block_len, i, j, n;
 198         const uint8_t *table;
 199
 200         s->coefs_start = 0;
 201         for (k = 0; k < s->nb_block_sizes; k++) {
 202                 block_len = s->frame_len >> k;
 203
 204                 table = NULL;
 205                 a = s->frame_len_bits - BLOCK_MIN_BITS - k;
 206                 if (a < 3) {
 207                         if (ahi->sample_rate >= 44100)
 208                                 table = exponent_band_44100[a];
 209                         else if (ahi->sample_rate >= 32000)
 210                                 table = exponent_band_32000[a];
 211                         else if (ahi->sample_rate >= 22050)
 212                                 table = exponent_band_22050[a];
 213                 }
 214                 if (table) {
 215                         n = *table++;
 216                         for (i = 0; i < n; i++)
 217                                 s->exponent_bands[k][i] = table[i];
 218                         s->exponent_sizes[k] = n;
 219                 } else {
 220                         j = 0;
 221                         lpos = 0;
 222                         for (i = 0; i < 25; i++) {
 223                                 a = wma_critical_freqs[i];
 224                                 b = ahi->sample_rate;
 225                                 pos = ((block_len * 2 * a) + (b << 1)) / (4 * b);
 226                                 pos <<= 2;
 227                                 if (pos > block_len)
 228                                         pos = block_len;
 229                                 if (pos > lpos)
 230                                         s->exponent_bands[k][j++] = pos - lpos;
 231                                 if (pos >= block_len)
 232                                         break;
 233                                 lpos = pos;
 234                         }
 235                         s->exponent_sizes[k] = j;
 236                 }
 237
 238                 /* max number of coefs */
 239                 s->coefs_end[k] = (s->frame_len - ((s->frame_len * 9) / 100)) >> k;
 240                 /* high freq computation */
 241                 s->high_band_start[k] = (int) ((block_len * 2 * high_freq)
 242                         / ahi->sample_rate + 0.5);
 243                 n = s->exponent_sizes[k];
 244                 j = 0;
 245                 pos = 0;
 246                 for (i = 0; i < n; i++) {
 247                         int start, end;
 248                         start = pos;
 249                         pos += s->exponent_bands[k][i];
 250                         end = pos;
 251                         if (start < s->high_band_start[k])
 252                                 start = s->high_band_start[k];
 253                         if (end > s->coefs_end[k])
 254                                 end = s->coefs_end[k];
 255                         if (end > start)
 256                                 s->exponent_high_bands[k][j++] = end - start;
 257                 }
 258                 s->exponent_high_sizes[k] = j;
 259         }
 260 }
 261
 262 static int wma_init(struct private_wmadec_data *s, int flags2, struct asf_header_info *ahi)
 263 {
 264         int i;
 265         float bps1, high_freq;
 266         volatile float bps;
 267         int sample_rate1;
 268         int coef_vlc_table;
 269
 270         if (ahi->sample_rate <= 0 || ahi->sample_rate > 50000
 271                 || ahi->channels <= 0 || ahi->channels > 8
 272                 || ahi->bit_rate <= 0)
 273                 return -E_WMA_BAD_PARAMS;
 274
 275         /* compute MDCT block size */
 276         if (ahi->sample_rate <= 16000) {
 277                 s->frame_len_bits = 9;
 278         } else if (ahi->sample_rate <= 22050) {
 279                 s->frame_len_bits = 10;
 280         } else {
 281                 s->frame_len_bits = 11;
 282         }
 283         s->frame_len = 1 << s->frame_len_bits;
 284         if (s->use_variable_block_len) {
 285                 int nb_max, nb;
 286                 nb = ((flags2 >> 3) & 3) + 1;
 287                 if ((ahi->bit_rate / ahi->channels) >= 32000)
 288                         nb += 2;
 289                 nb_max = s->frame_len_bits - BLOCK_MIN_BITS;
 290                 if (nb > nb_max)
 291                         nb = nb_max;
 292                 s->nb_block_sizes = nb + 1;
 293         } else {
 294                 s->nb_block_sizes = 1;
 295         }
 296
 297         /* init rate dependent parameters */
 298         s->use_noise_coding = 1;
 299         high_freq = ahi->sample_rate * 0.5;
 300
 301         /* wma2 rates are normalized */
 302         sample_rate1 = ahi->sample_rate;
 303         if (sample_rate1 >= 44100)
 304                 sample_rate1 = 44100;
 305         else if (sample_rate1 >= 22050)
 306                 sample_rate1 = 22050;
 307         else if (sample_rate1 >= 16000)
 308                 sample_rate1 = 16000;
 309         else if (sample_rate1 >= 11025)
 310                 sample_rate1 = 11025;
 311         else if (sample_rate1 >= 8000)
 312                 sample_rate1 = 8000;
 313
 314         bps = (float) ahi->bit_rate / (float) (ahi->channels * ahi->sample_rate);
 315         s->byte_offset_bits = wma_log2((int) (bps * s->frame_len / 8.0 + 0.5)) + 2;
 316         /*
 317          * Compute high frequency value and choose if noise coding should be
 318          * activated.
 319          */
 320         bps1 = bps;
 321         if (ahi->channels == 2)
 322                 bps1 = bps * 1.6;
 323         if (sample_rate1 == 44100) {
 324                 if (bps1 >= 0.61)
 325                         s->use_noise_coding = 0;
 326                 else
 327                         high_freq = high_freq * 0.4;
 328         } else if (sample_rate1 == 22050) {
 329                 if (bps1 >= 1.16)
 330                         s->use_noise_coding = 0;
 331                 else if (bps1 >= 0.72)
 332                         high_freq = high_freq * 0.7;
 333                 else
 334                         high_freq = high_freq * 0.6;
 335         } else if (sample_rate1 == 16000) {
 336                 if (bps > 0.5)
 337                         high_freq = high_freq * 0.5;
 338                 else
 339                         high_freq = high_freq * 0.3;
 340         } else if (sample_rate1 == 11025) {
 341                 high_freq = high_freq * 0.7;
 342         } else if (sample_rate1 == 8000) {
 343                 if (bps <= 0.625) {
 344                         high_freq = high_freq * 0.5;
 345                 } else if (bps > 0.75) {
 346                         s->use_noise_coding = 0;
 347                 } else {
 348                         high_freq = high_freq * 0.65;
 349                 }
 350         } else {
 351                 if (bps >= 0.8) {
 352                         high_freq = high_freq * 0.75;
 353                 } else if (bps >= 0.6) {
 354                         high_freq = high_freq * 0.6;
 355                 } else {
 356                         high_freq = high_freq * 0.5;
 357                 }
 358         }
 359         PARA_INFO_LOG("channels=%d sample_rate=%d "
 360                 "bitrate=%d block_align=%d\n",
 361                 ahi->channels, ahi->sample_rate,
 362                 ahi->bit_rate, ahi->block_align);
 363         PARA_INFO_LOG("frame_len=%d, bps=%f bps1=%f "
 364                 "high_freq=%f bitoffset=%d\n",
 365                 s->frame_len, bps, bps1,
 366                 high_freq, s->byte_offset_bits);
 367         PARA_INFO_LOG("use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n",
 368                 s->use_noise_coding, s->use_exp_vlc, s->nb_block_sizes);
 369
 370         compute_scale_factor_band_sizes(s, high_freq);
 371         /* init MDCT windows : simple sinus window */
 372         for (i = 0; i < s->nb_block_sizes; i++) {
 373                 int n;
 374                 n = 1 << (s->frame_len_bits - i);
 375                 sine_window_init(ff_sine_windows[s->frame_len_bits - i - 7], n);
 376                 s->windows[i] = ff_sine_windows[s->frame_len_bits - i - 7];
 377         }
 378
 379         s->reset_block_lengths = 1;
 380
 381         if (s->use_noise_coding) {
 382                 /* init the noise generator */
 383                 if (s->use_exp_vlc)
 384                         s->noise_mult = 0.02;
 385                 else
 386                         s->noise_mult = 0.04;
 387
 388                 {
 389                         unsigned int seed;
 390                         float norm;
 391                         seed = 1;
 392                         norm = (1.0 / (float) (1LL << 31)) * sqrt(3) * s->noise_mult;
 393                         for (i = 0; i < NOISE_TAB_SIZE; i++) {
 394                                 seed = seed * 314159 + 1;
 395                                 s->noise_table[i] = (float) ((int) seed) * norm;
 396                         }
 397                 }
 398         }
 399
 400         /* choose the VLC tables for the coefficients */
 401         coef_vlc_table = 2;
 402         if (ahi->sample_rate >= 32000) {
 403                 if (bps1 < 0.72)
 404                         coef_vlc_table = 0;
 405                 else if (bps1 < 1.16)
 406                         coef_vlc_table = 1;
 407         }
 408         s->coef_vlcs[0] = &coef_vlcs[coef_vlc_table * 2];
 409         s->coef_vlcs[1] = &coef_vlcs[coef_vlc_table * 2 + 1];
 410         init_coef_vlc(&s->coef_vlc[0], &s->run_table[0], &s->level_table[0],
 411                 &s->int_table[0], s->coef_vlcs[0]);
 412         init_coef_vlc(&s->coef_vlc[1], &s->run_table[1], &s->level_table[1],
 413                 &s->int_table[1], s->coef_vlcs[1]);
 414         return 0;
 415 }
 416
 417 static void wma_lsp_to_curve_init(struct private_wmadec_data *s, int frame_len)
 418 {
 419         float wdel, a, b;
 420         int i, e, m;
 421
 422         wdel = M_PI / frame_len;
 423         for (i = 0; i < frame_len; i++)
 424                 s->lsp_cos_table[i] = 2.0f * cos(wdel * i);
 425
 426         /* tables for x^-0.25 computation */
 427         for (i = 0; i < 256; i++) {
 428                 e = i - 126;
 429                 s->lsp_pow_e_table[i] = pow(2.0, e * -0.25);
 430         }
 431
 432         /* These two tables are needed to avoid two operations in pow_m1_4. */
 433         b = 1.0;
 434         for (i = (1 << LSP_POW_BITS) - 1; i >= 0; i--) {
 435                 m = (1 << LSP_POW_BITS) + i;
 436                 a = (float) m *(0.5 / (1 << LSP_POW_BITS));
 437                 a = pow(a, -0.25);
 438                 s->lsp_pow_m_table1[i] = 2 * a - b;
 439                 s->lsp_pow_m_table2[i] = b - a;
 440                 b = a;
 441         }
 442 }
 443
 444 static int wma_decode_init(char *initial_buf, int len, struct private_wmadec_data **result)
 445 {
 446         struct private_wmadec_data *s;
 447         int ret, i;
 448
 449         if (len < 18)
 450                 return 0;
 451
 452         PARA_NOTICE_LOG("initial buf: %d bytes\n", len);
 453         s = para_calloc(sizeof(*s));
 454         ret = read_asf_header(initial_buf, len, &s->ahi);
 455         if (ret < 0)
 456                 return ret;
 457
 458         s->use_exp_vlc = s->ahi.flags2 & 0x0001;
 459         s->use_bit_reservoir = s->ahi.flags2 & 0x0002;
 460         s->use_variable_block_len = s->ahi.flags2 & 0x0004;
 461
 462         ret = wma_init(s, s->ahi.flags2, &s->ahi);
 463         if (ret < 0)
 464                 return ret;
 465         /* init MDCT */
 466         for (i = 0; i < s->nb_block_sizes; i++) {
 467                 ret = mdct_init(s->frame_len_bits - i + 1, 1, &s->mdct_ctx[i]);
 468                 if (ret < 0)
 469                         return ret;
 470         }
 471         if (s->use_noise_coding) {
 472                 PARA_INFO_LOG("using noise coding\n");
 473                 init_vlc(&s->hgain_vlc, HGAINVLCBITS,
 474                         sizeof (ff_wma_hgain_huffbits), ff_wma_hgain_huffbits,
 475                         1, 1, ff_wma_hgain_huffcodes, 2, 2);
 476         }
 477
 478         if (s->use_exp_vlc) {
 479                 PARA_INFO_LOG("using exp_vlc\n");
 480                 init_vlc(&s->exp_vlc, EXPVLCBITS,
 481                 sizeof (ff_wma_scale_huffbits), ff_wma_scale_huffbits,
 482                 1, 1, ff_wma_scale_huffcodes, 4, 4);
 483         } else {
 484                 PARA_INFO_LOG("using curve\n");
 485                 wma_lsp_to_curve_init(s, s->frame_len);
 486         }
 487         *result = s;
 488         return s->ahi.header_len;
 489 }
 490
 491 /**
 492  * compute x^-0.25 with an exponent and mantissa table. We use linear
 493  * interpolation to reduce the mantissa table size at a small speed
 494  * expense (linear interpolation approximately doubles the number of
 495  * bits of precision).
 496  */
 497 static inline float pow_m1_4(struct private_wmadec_data *s, float x)
 498 {
 499         union {
 500                 float f;
 501                 unsigned int v;
 502         } u, t;
 503         unsigned int e, m;
 504         float a, b;
 505
 506         u.f = x;
 507         e = u.v >> 23;
 508         m = (u.v >> (23 - LSP_POW_BITS)) & ((1 << LSP_POW_BITS) - 1);
 509         /* build interpolation scale: 1 <= t < 2. */
 510         t.v = ((u.v << LSP_POW_BITS) & ((1 << 23) - 1)) | (127 << 23);
 511         a = s->lsp_pow_m_table1[m];
 512         b = s->lsp_pow_m_table2[m];
 513         return s->lsp_pow_e_table[e] * (a + b * t.f);
 514 }
 515
 516 static void wma_lsp_to_curve(struct private_wmadec_data *s,
 517                 float *out, float *val_max_ptr, int n, float *lsp)
 518 {
 519         int i, j;
 520         float p, q, w, v, val_max;
 521
 522         val_max = 0;
 523         for (i = 0; i < n; i++) {
 524                 p = 0.5f;
 525                 q = 0.5f;
 526                 w = s->lsp_cos_table[i];
 527                 for (j = 1; j < NB_LSP_COEFS; j += 2) {
 528                         q *= w - lsp[j - 1];
 529                         p *= w - lsp[j];
 530                 }
 531                 p *= p * (2.0f - w);
 532                 q *= q * (2.0f + w);
 533                 v = p + q;
 534                 v = pow_m1_4(s, v);
 535                 if (v > val_max)
 536                         val_max = v;
 537                 out[i] = v;
 538         }
 539         *val_max_ptr = val_max;
 540 }
 541
 542 /* Decode exponents coded with LSP coefficients (same idea as Vorbis). */
 543 static void decode_exp_lsp(struct private_wmadec_data *s, int ch)
 544 {
 545         float lsp_coefs[NB_LSP_COEFS];
 546         int val, i;
 547
 548         for (i = 0; i < NB_LSP_COEFS; i++) {
 549                 if (i == 0 || i >= 8)
 550                         val = get_bits(&s->gb, 3);
 551                 else
 552                         val = get_bits(&s->gb, 4);
 553                 lsp_coefs[i] = ff_wma_lsp_codebook[i][val];
 554         }
 555
 556         wma_lsp_to_curve(s, s->exponents[ch], &s->max_exponent[ch],
 557                          s->block_len, lsp_coefs);
 558 }
 559
 560 /*
 561  * Parse a vlc code, faster then get_vlc().
 562  *
 563  * \param bits The number of bits which will be read at once, must be
 564  * identical to nb_bits in init_vlc()
 565  *
 566  * \param max_depth The number of times bits bits must be read to completely
 567  * read the longest vlc code = (max_vlc_length + bits - 1) / bits.
 568  */
 569 static int get_vlc2(struct getbit_context *s, VLC_TYPE(*table)[2],
 570                 int bits, int max_depth)
 571 {
 572         int code;
 573
 574         OPEN_READER(re, s)
 575         UPDATE_CACHE(re, s)
 576         GET_VLC(code, re, s, table, bits, max_depth)
 577         CLOSE_READER(re, s)
 578         return code;
 579 }
 580
 581 /* Decode exponents coded with VLC codes. */
 582 static int decode_exp_vlc(struct private_wmadec_data *s, int ch)
 583 {
 584         int last_exp, n, code;
 585         const uint16_t *ptr, *band_ptr;
 586         float v, *q, max_scale, *q_end;
 587
 588         band_ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits];
 589         ptr = band_ptr;
 590         q = s->exponents[ch];
 591         q_end = q + s->block_len;
 592         max_scale = 0;
 593         last_exp = 36;
 594
 595         while (q < q_end) {
 596                 code = get_vlc2(&s->gb, s->exp_vlc.table, EXPVLCBITS, EXPMAX);
 597                 if (code < 0)
 598                         return -1;
 599                 /* NOTE: this offset is the same as MPEG4 AAC ! */
 600                 last_exp += code - 60;
 601                 /* XXX: use a table */
 602                 v = pow(10, last_exp * (1.0 / 16.0));
 603                 if (v > max_scale)
 604                         max_scale = v;
 605                 n = *ptr++;
 606                 do {
 607                         *q++ = v;
 608                 } while (--n);
 609         }
 610         s->max_exponent[ch] = max_scale;
 611         return 0;
 612 }
 613
 614 static void vector_fmul_add(float *dst, const float *src0, const float *src1,
 615                 const float *src2, int src3, int len, int step)
 616 {
 617         int i;
 618         for (i = 0; i < len; i++)
 619                 dst[i * step] = src0[i] * src1[i] + src2[i] + src3;
 620 }
 621
 622 static void vector_fmul_reverse_c(float *dst, const float *src0,
 623                 const float *src1, int len)
 624 {
 625         int i;
 626         src1 += len - 1;
 627         for (i = 0; i < len; i++)
 628                 dst[i] = src0[i] * src1[-i];
 629 }
 630
 631 /**
 632  * Apply MDCT window and add into output.
 633  *
 634  * We ensure that when the windows overlap their squared sum
 635  * is always 1 (MDCT reconstruction rule).
 636  */
 637 static void wma_window(struct private_wmadec_data *s, float *out)
 638 {
 639         float *in = s->output;
 640         int block_len, bsize, n;
 641
 642         /* left part */
 643         if (s->block_len_bits <= s->prev_block_len_bits) {
 644                 block_len = s->block_len;
 645                 bsize = s->frame_len_bits - s->block_len_bits;
 646
 647                 vector_fmul_add(out, in, s->windows[bsize],
 648                                          out, 0, block_len, 1);
 649
 650         } else {
 651                 block_len = 1 << s->prev_block_len_bits;
 652                 n = (s->block_len - block_len) / 2;
 653                 bsize = s->frame_len_bits - s->prev_block_len_bits;
 654
 655                 vector_fmul_add(out + n, in + n, s->windows[bsize],
 656                                          out + n, 0, block_len, 1);
 657
 658                 memcpy(out + n + block_len, in + n + block_len,
 659                        n * sizeof (float));
 660         }
 661
 662         out += s->block_len;
 663         in += s->block_len;
 664
 665         /* right part */
 666         if (s->block_len_bits <= s->next_block_len_bits) {
 667                 block_len = s->block_len;
 668                 bsize = s->frame_len_bits - s->block_len_bits;
 669
 670                 vector_fmul_reverse_c(out, in, s->windows[bsize], block_len);
 671
 672         } else {
 673                 block_len = 1 << s->next_block_len_bits;
 674                 n = (s->block_len - block_len) / 2;
 675                 bsize = s->frame_len_bits - s->next_block_len_bits;
 676
 677                 memcpy(out, in, n * sizeof (float));
 678
 679                 vector_fmul_reverse_c(out + n, in + n, s->windows[bsize],
 680                                       block_len);
 681
 682                 memset(out + n + block_len, 0, n * sizeof (float));
 683         }
 684 }
 685
 686 static int wma_total_gain_to_bits(int total_gain)
 687 {
 688         if (total_gain < 15)
 689                 return 13;
 690         else if (total_gain < 32)
 691                 return 12;
 692         else if (total_gain < 40)
 693                 return 11;
 694         else if (total_gain < 45)
 695                 return 10;
 696         else
 697                 return 9;
 698 }
 699
 700 /**
 701  * @return 0 if OK. 1 if last block of frame. return -1 if
 702  * unrecorrable error.
 703  */
 704 static int wma_decode_block(struct private_wmadec_data *s)
 705 {
 706         int n, v, ch, code, bsize;
 707         int coef_nb_bits, total_gain;
 708         int nb_coefs[MAX_CHANNELS];
 709         float mdct_norm;
 710
 711         /* compute current block length */
 712         if (s->use_variable_block_len) {
 713                 n = wma_log2(s->nb_block_sizes - 1) + 1;
 714
 715                 if (s->reset_block_lengths) {
 716                         s->reset_block_lengths = 0;
 717                         v = get_bits(&s->gb, n);
 718                         if (v >= s->nb_block_sizes)
 719                                 return -1;
 720                         s->prev_block_len_bits = s->frame_len_bits - v;
 721                         v = get_bits(&s->gb, n);
 722                         if (v >= s->nb_block_sizes)
 723                                 return -1;
 724                         s->block_len_bits = s->frame_len_bits - v;
 725                 } else {
 726                         /* update block lengths */
 727                         s->prev_block_len_bits = s->block_len_bits;
 728                         s->block_len_bits = s->next_block_len_bits;
 729                 }
 730                 v = get_bits(&s->gb, n);
 731                 if (v >= s->nb_block_sizes)
 732                         return -1;
 733                 s->next_block_len_bits = s->frame_len_bits - v;
 734         } else {
 735                 /* fixed block len */
 736                 s->next_block_len_bits = s->frame_len_bits;
 737                 s->prev_block_len_bits = s->frame_len_bits;
 738                 s->block_len_bits = s->frame_len_bits;
 739         }
 740
 741         /* now check if the block length is coherent with the frame length */
 742         s->block_len = 1 << s->block_len_bits;
 743         if ((s->block_pos + s->block_len) > s->frame_len)
 744                 return -E_INCOHERENT_BLOCK_LEN;
 745
 746         if (s->ahi.channels == 2) {
 747                 s->ms_stereo = get_bits1(&s->gb);
 748         }
 749         v = 0;
 750         for (ch = 0; ch < s->ahi.channels; ch++) {
 751                 int a = get_bits1(&s->gb);
 752                 s->channel_coded[ch] = a;
 753                 v |= a;
 754         }
 755
 756         bsize = s->frame_len_bits - s->block_len_bits;
 757
 758         /* if no channel coded, no need to go further */
 759         /* XXX: fix potential framing problems */
 760         if (!v)
 761                 goto next;
 762
 763         /* read total gain and extract corresponding number of bits for
 764            coef escape coding */
 765         total_gain = 1;
 766         for (;;) {
 767                 int a = get_bits(&s->gb, 7);
 768                 total_gain += a;
 769                 if (a != 127)
 770                         break;
 771         }
 772
 773         coef_nb_bits = wma_total_gain_to_bits(total_gain);
 774
 775         /* compute number of coefficients */
 776         n = s->coefs_end[bsize] - s->coefs_start;
 777         for (ch = 0; ch < s->ahi.channels; ch++)
 778                 nb_coefs[ch] = n;
 779
 780         /* complex coding */
 781         if (s->use_noise_coding) {
 782
 783                 for (ch = 0; ch < s->ahi.channels; ch++) {
 784                         if (s->channel_coded[ch]) {
 785                                 int i, m, a;
 786                                 m = s->exponent_high_sizes[bsize];
 787                                 for (i = 0; i < m; i++) {
 788                                         a = get_bits1(&s->gb);
 789                                         s->high_band_coded[ch][i] = a;
 790                                         /* if noise coding, the coefficients are not transmitted */
 791                                         if (a)
 792                                                 nb_coefs[ch] -=
 793                                                     s->
 794                                                     exponent_high_bands[bsize]
 795                                                     [i];
 796                                 }
 797                         }
 798                 }
 799                 for (ch = 0; ch < s->ahi.channels; ch++) {
 800                         if (s->channel_coded[ch]) {
 801                                 int i, val;
 802
 803                                 n = s->exponent_high_sizes[bsize];
 804                                 val = (int) 0x80000000;
 805                                 for (i = 0; i < n; i++) {
 806                                         if (s->high_band_coded[ch][i]) {
 807                                                 if (val == (int) 0x80000000) {
 808                                                         val =
 809                                                             get_bits(&s->gb,
 810                                                                      7) - 19;
 811                                                 } else {
 812                                                         code =
 813                                                             get_vlc2(&s->gb,
 814                                                                      s->
 815                                                                      hgain_vlc.
 816                                                                      table,
 817                                                                      HGAINVLCBITS,
 818                                                                      HGAINMAX);
 819                                                         if (code < 0)
 820                                                                 return -1;
 821                                                         val += code - 18;
 822                                                 }
 823                                                 s->high_band_values[ch][i] =
 824                                                     val;
 825                                         }
 826                                 }
 827                         }
 828                 }
 829         }
 830
 831         /* exponents can be reused in short blocks. */
 832         if ((s->block_len_bits == s->frame_len_bits) || get_bits1(&s->gb)) {
 833                 for (ch = 0; ch < s->ahi.channels; ch++) {
 834                         if (s->channel_coded[ch]) {
 835                                 if (s->use_exp_vlc) {
 836                                         if (decode_exp_vlc(s, ch) < 0)
 837                                                 return -1;
 838                                 } else {
 839                                         decode_exp_lsp(s, ch);
 840                                 }
 841                                 s->exponents_bsize[ch] = bsize;
 842                         }
 843                 }
 844         }
 845
 846         /* parse spectral coefficients : just RLE encoding */
 847         for (ch = 0; ch < s->ahi.channels; ch++) {
 848                 if (s->channel_coded[ch]) {
 849                         struct vlc *coef_vlc;
 850                         int level, run, sign, tindex;
 851                         int16_t *ptr, *eptr;
 852                         const uint16_t *level_table, *run_table;
 853
 854                         /* special VLC tables are used for ms stereo because
 855                            there is potentially less energy there */
 856                         tindex = (ch == 1 && s->ms_stereo);
 857                         coef_vlc = &s->coef_vlc[tindex];
 858                         run_table = s->run_table[tindex];
 859                         level_table = s->level_table[tindex];
 860                         /* XXX: optimize */
 861                         ptr = &s->coefs1[ch][0];
 862                         eptr = ptr + nb_coefs[ch];
 863                         memset(ptr, 0, s->block_len * sizeof(int16_t));
 864                         for (;;) {
 865                                 code =
 866                                     get_vlc2(&s->gb, coef_vlc->table, VLCBITS,
 867                                              VLCMAX);
 868                                 if (code < 0)
 869                                         return -1;
 870                                 if (code == 1) {
 871                                         /* EOB */
 872                                         break;
 873                                 } else if (code == 0) {
 874                                         /* escape */
 875                                         level = get_bits(&s->gb, coef_nb_bits);
 876                                         /* NOTE: this is rather suboptimal. reading
 877                                            block_len_bits would be better */
 878                                         run =
 879                                             get_bits(&s->gb, s->frame_len_bits);
 880                                 } else {
 881                                         /* normal code */
 882                                         run = run_table[code];
 883                                         level = level_table[code];
 884                                 }
 885                                 sign = get_bits1(&s->gb);
 886                                 if (!sign)
 887                                         level = -level;
 888                                 ptr += run;
 889                                 if (ptr >= eptr) {
 890                                         PARA_ERROR_LOG("overflow in spectral RLE, ignoring\n");
 891                                         break;
 892                                 }
 893                                 *ptr++ = level;
 894                                 /* NOTE: EOB can be omitted */
 895                                 if (ptr >= eptr)
 896                                         break;
 897                         }
 898                 }
 899         }
 900
 901         /* normalize */
 902         {
 903                 int n4 = s->block_len / 2;
 904                 mdct_norm = 1.0 / (float) n4;
 905         }
 906
 907         /* finally compute the MDCT coefficients */
 908         for (ch = 0; ch < s->ahi.channels; ch++) {
 909                 if (s->channel_coded[ch]) {
 910                         int16_t *coefs1;
 911                         float *coefs, *exponents, mult, mult1, noise;
 912                         int i, j, n1, last_high_band, esize;
 913                         float exp_power[HIGH_BAND_MAX_SIZE];
 914
 915                         coefs1 = s->coefs1[ch];
 916                         exponents = s->exponents[ch];
 917                         esize = s->exponents_bsize[ch];
 918                         mult = pow(10, total_gain * 0.05) / s->max_exponent[ch];
 919                         mult *= mdct_norm;
 920                         coefs = s->coefs[ch];
 921                         if (s->use_noise_coding) {
 922                                 mult1 = mult;
 923                                 /* very low freqs : noise */
 924                                 for (i = 0; i < s->coefs_start; i++) {
 925                                         *coefs++ =
 926                                             s->noise_table[s->noise_index] *
 927                                             exponents[i << bsize >> esize] *
 928                                             mult1;
 929                                         s->noise_index =
 930                                             (s->noise_index +
 931                                              1) & (NOISE_TAB_SIZE - 1);
 932                                 }
 933
 934                                 n1 = s->exponent_high_sizes[bsize];
 935
 936                                 /* compute power of high bands */
 937                                 exponents = s->exponents[ch] +
 938                                     (s->high_band_start[bsize] << bsize);
 939                                 last_high_band = 0;     /* avoid warning */
 940                                 for (j = 0; j < n1; j++) {
 941                                         n = s->exponent_high_bands[s->
 942                                                                    frame_len_bits
 943                                                                    -
 944                                                                    s->
 945                                                                    block_len_bits]
 946                                             [j];
 947                                         if (s->high_band_coded[ch][j]) {
 948                                                 float e2, val;
 949                                                 e2 = 0;
 950                                                 for (i = 0; i < n; i++) {
 951                                                         val = exponents[i << bsize
 952                                                                       >> esize];
 953                                                         e2 += val * val;
 954                                                 }
 955                                                 exp_power[j] = e2 / n;
 956                                                 last_high_band = j;
 957                                         }
 958                                         exponents += n << bsize;
 959                                 }
 960
 961                                 /* main freqs and high freqs */
 962                                 exponents =
 963                                     s->exponents[ch] +
 964                                     (s->coefs_start << bsize);
 965                                 for (j = -1; j < n1; j++) {
 966                                         if (j < 0) {
 967                                                 n = s->high_band_start[bsize] -
 968                                                     s->coefs_start;
 969                                         } else {
 970                                                 n = s->exponent_high_bands[s->
 971                                                                            frame_len_bits
 972                                                                            -
 973                                                                            s->
 974                                                                            block_len_bits]
 975                                                     [j];
 976                                         }
 977                                         if (j >= 0 && s->high_band_coded[ch][j]) {
 978                                                 /* use noise with specified power */
 979                                                 mult1 =
 980                                                     sqrt(exp_power[j] /
 981                                                          exp_power
 982                                                          [last_high_band]);
 983                                                 /* XXX: use a table */
 984                                                 mult1 =
 985                                                     mult1 * pow(10,
 986                                                                 s->
 987                                                                 high_band_values
 988                                                                 [ch][j] * 0.05);
 989                                                 mult1 =
 990                                                     mult1 /
 991                                                     (s->max_exponent[ch] *
 992                                                      s->noise_mult);
 993                                                 mult1 *= mdct_norm;
 994                                                 for (i = 0; i < n; i++) {
 995                                                         noise =
 996                                                             s->noise_table[s->
 997                                                                            noise_index];
 998                                                         s->noise_index =
 999                                                             (s->noise_index +
1000                                                              1) &
1001                                                             (NOISE_TAB_SIZE -
1002                                                              1);
1003                                                         *coefs++ =
1004                                                             noise *
1005                                                             exponents[i << bsize
1006                                                                       >> esize]
1007                                                             * mult1;
1008                                                 }
1009                                                 exponents += n << bsize;
1010                                         } else {
1011                                                 /* coded values + small noise */
1012                                                 for (i = 0; i < n; i++) {
1013                                                         noise =
1014                                                             s->noise_table[s->
1015                                                                            noise_index];
1016                                                         s->noise_index =
1017                                                             (s->noise_index +
1018                                                              1) &
1019                                                             (NOISE_TAB_SIZE -
1020                                                              1);
1021                                                         *coefs++ =
1022                                                             ((*coefs1++) +
1023                                                              noise) *
1024                                                             exponents[i << bsize
1025                                                                       >> esize]
1026                                                             * mult;
1027                                                 }
1028                                                 exponents += n << bsize;
1029                                         }
1030                                 }
1031
1032                                 /* very high freqs : noise */
1033                                 n = s->block_len - s->coefs_end[bsize];
1034                                 mult1 =
1035                                     mult * exponents[((-1 << bsize)) >> esize];
1036                                 for (i = 0; i < n; i++) {
1037                                         *coefs++ =
1038                                             s->noise_table[s->noise_index] *
1039                                             mult1;
1040                                         s->noise_index =
1041                                             (s->noise_index +
1042                                              1) & (NOISE_TAB_SIZE - 1);
1043                                 }
1044                         } else {
1045                                 /* XXX: optimize more */
1046                                 for (i = 0; i < s->coefs_start; i++)
1047                                         *coefs++ = 0.0;
1048                                 n = nb_coefs[ch];
1049                                 for (i = 0; i < n; i++) {
1050                                         *coefs++ =
1051                                             coefs1[i] *
1052                                             exponents[i << bsize >> esize] *
1053                                             mult;
1054                                 }
1055                                 n = s->block_len - s->coefs_end[bsize];
1056                                 for (i = 0; i < n; i++)
1057                                         *coefs++ = 0.0;
1058                         }
1059                 }
1060         }
1061
1062         if (s->ms_stereo && s->channel_coded[1]) {
1063                 float a, b;
1064                 int i;
1065
1066                 /*
1067                  * Nominal case for ms stereo: we do it before mdct.
1068                  *
1069                  * No need to optimize this case because it should almost never
1070                  * happen.
1071                  */
1072                 if (!s->channel_coded[0]) {
1073                         PARA_NOTICE_LOG("rare ms-stereo\n");
1074                         memset(s->coefs[0], 0, sizeof(float) * s->block_len);
1075                         s->channel_coded[0] = 1;
1076                 }
1077                 for (i = 0; i < s->block_len; i++) {
1078                         a = s->coefs[0][i];
1079                         b = s->coefs[1][i];
1080                         s->coefs[0][i] = a + b;
1081                         s->coefs[1][i] = a - b;
1082                 }
1083         }
1084
1085 next:
1086         for (ch = 0; ch < s->ahi.channels; ch++) {
1087                 int n4, index;
1088
1089                 n = s->block_len;
1090                 n4 = s->block_len / 2;
1091                 if (s->channel_coded[ch])
1092                         imdct(s->mdct_ctx[bsize], s->output, s->coefs[ch]);
1093                 else if (!(s->ms_stereo && ch == 1))
1094                         memset(s->output, 0, sizeof (s->output));
1095
1096                 /* multiply by the window and add in the frame */
1097                 index = (s->frame_len / 2) + s->block_pos - n4;
1098                 wma_window(s, &s->frame_out[ch][index]);
1099         }
1100
1101         /* update block number */
1102         s->block_num++;
1103         s->block_pos += s->block_len;
1104         if (s->block_pos >= s->frame_len)
1105                 return 1;
1106         else
1107                 return 0;
1108 }
1109
1110 /*
1111  * Clip a signed integer value into the -32768,32767 range.
1112  *
1113  * \param a The value to clip.
1114  *
1115  * \return The clipped value.
1116  */
1117 static inline int16_t av_clip_int16(int a)
1118 {
1119         if ((a + 32768) & ~65535)
1120                 return (a >> 31) ^ 32767;
1121         else
1122                 return a;
1123 }
1124
1125 /* Decode a frame of frame_len samples. */
1126 static int wma_decode_frame(struct private_wmadec_data *s, int16_t * samples)
1127 {
1128         int ret, i, n, ch, incr;
1129         int16_t *ptr;
1130         float *iptr;
1131
1132         /* read each block */
1133         s->block_num = 0;
1134         s->block_pos = 0;
1135         for (;;) {
1136                 ret = wma_decode_block(s);
1137                 if (ret < 0)
1138                         return -1;
1139                 if (ret)
1140                         break;
1141         }
1142
1143         /* convert frame to integer */
1144         n = s->frame_len;
1145         incr = s->ahi.channels;
1146         for (ch = 0; ch < s->ahi.channels; ch++) {
1147                 ptr = samples + ch;
1148                 iptr = s->frame_out[ch];
1149
1150                 for (i = 0; i < n; i++) {
1151                         *ptr = av_clip_int16(lrintf(*iptr++));
1152                         ptr += incr;
1153                 }
1154                 /* prepare for next block */
1155                 memmove(&s->frame_out[ch][0], &s->frame_out[ch][s->frame_len],
1156                         s->frame_len * sizeof (float));
1157         }
1158         return 0;
1159 }
1160
1161 static int wma_decode_superframe(struct private_wmadec_data *s, void *data,
1162                 int *data_size, const uint8_t *buf, int buf_size)
1163 {
1164         int ret, nb_frames, bit_offset, i, pos, len;
1165         uint8_t *q;
1166         int16_t *samples;
1167         static int frame_count;
1168
1169         if (buf_size == 0) {
1170                 s->last_superframe_len = 0;
1171                 return 0;
1172         }
1173         if (buf_size < s->ahi.block_align)
1174                 return 0;
1175         buf_size = s->ahi.block_align;
1176         samples = data;
1177         init_get_bits(&s->gb, buf, buf_size * 8);
1178         if (s->use_bit_reservoir) {
1179                 /* read super frame header */
1180                 skip_bits(&s->gb, 4);   /* super frame index */
1181                 nb_frames = get_bits(&s->gb, 4) - 1;
1182                 // PARA_DEBUG_LOG("have %d frames\n", nb_frames);
1183                 ret = -E_WMA_OUTPUT_SPACE;
1184                 if ((nb_frames + 1) * s->ahi.channels * s->frame_len
1185                                 * sizeof(int16_t) > *data_size)
1186                         goto fail;
1187
1188                 bit_offset = get_bits(&s->gb, s->byte_offset_bits + 3);
1189
1190                 if (s->last_superframe_len > 0) {
1191                         /* add bit_offset bits to last frame */
1192                         ret = -E_WMA_BAD_SUPERFRAME;
1193                         if ((s->last_superframe_len + ((bit_offset + 7) >> 3)) >
1194                                         MAX_CODED_SUPERFRAME_SIZE)
1195                                 goto fail;
1196                         q = s->last_superframe + s->last_superframe_len;
1197                         len = bit_offset;
1198                         while (len > 7) {
1199                                 *q++ = get_bits(&s->gb, 8);
1200                                 len -= 8;
1201                         }
1202                         if (len > 0) {
1203                                 *q++ = get_bits(&s->gb, len) << (8 - len);
1204                         }
1205
1206                         /* XXX: bit_offset bits into last frame */
1207                         init_get_bits(&s->gb, s->last_superframe,
1208                                 MAX_CODED_SUPERFRAME_SIZE * 8);
1209                         /* skip unused bits */
1210                         if (s->last_bitoffset > 0)
1211                                 skip_bits(&s->gb, s->last_bitoffset);
1212                         /*
1213                          * This frame is stored in the last superframe and in
1214                          * the current one.
1215                          */
1216                         ret = -E_WMA_DECODE;
1217                         if (wma_decode_frame(s, samples) < 0)
1218                                 goto fail;
1219                         frame_count++;
1220                         samples += s->ahi.channels * s->frame_len;
1221                 }
1222
1223                 /* read each frame starting from bit_offset */
1224                 pos = bit_offset + 4 + 4 + s->byte_offset_bits + 3;
1225                 init_get_bits(&s->gb, buf + (pos >> 3),
1226                         (MAX_CODED_SUPERFRAME_SIZE - (pos >> 3)) * 8);
1227                 len = pos & 7;
1228                 if (len > 0)
1229                         skip_bits(&s->gb, len);
1230
1231                 s->reset_block_lengths = 1;
1232                 for (i = 0; i < nb_frames; i++) {
1233                         ret = -E_WMA_DECODE;
1234                         if (wma_decode_frame(s, samples) < 0)
1235                                 goto fail;
1236                         frame_count++;
1237                         samples += s->ahi.channels * s->frame_len;
1238                 }
1239
1240                 /* we copy the end of the frame in the last frame buffer */
1241                 pos = get_bits_count(&s->gb) +
1242                         ((bit_offset + 4 + 4 + s->byte_offset_bits + 3) & ~7);
1243                 s->last_bitoffset = pos & 7;
1244                 pos >>= 3;
1245                 len = buf_size - pos;
1246                 ret = -E_WMA_BAD_SUPERFRAME;
1247                 if (len > MAX_CODED_SUPERFRAME_SIZE || len < 0) {
1248                         goto fail;
1249                 }
1250                 s->last_superframe_len = len;
1251                 memcpy(s->last_superframe, buf + pos, len);
1252         } else {
1253                 PARA_DEBUG_LOG("not using bit reservoir\n");
1254                 ret = -E_WMA_OUTPUT_SPACE;
1255                 if (s->ahi.channels * s->frame_len * sizeof(int16_t) > *data_size)
1256                         goto fail;
1257                 /* single frame decode */
1258                 ret = -E_WMA_DECODE;
1259                 if (wma_decode_frame(s, samples) < 0)
1260                         goto fail;
1261                 frame_count++;
1262                 samples += s->ahi.channels * s->frame_len;
1263         }
1264         PARA_DEBUG_LOG("frame_count: %d frame_len: %d, block_len: %d, "
1265                 "outbytes: %d, eaten: %d\n",
1266                 frame_count, s->frame_len, s->block_len,
1267                 (int8_t *) samples - (int8_t *) data, s->ahi.block_align);
1268         *data_size = (int8_t *)samples - (int8_t *)data;
1269         return s->ahi.block_align;
1270 fail:
1271         /* reset the bit reservoir on errors */
1272         s->last_superframe_len = 0;
1273         return ret;
1274 }
1275
1276 static ssize_t wmadec_convert(char *inbuffer, size_t len,
1277                 struct filter_node *fn)
1278 {
1279         int ret, out_size = fn->bufsize - fn->loaded;
1280         struct private_wmadec_data *pwd = fn->private_data;
1281
1282         if (out_size < 128 * 1024)
1283                 return 0;
1284         if (!pwd) {
1285                 ret = wma_decode_init(inbuffer, len, &pwd);
1286                 if (ret <= 0)
1287                         return ret;
1288                 fn->private_data = pwd;
1289                 fn->fc->channels = pwd->ahi.channels;
1290                 fn->fc->samplerate = pwd->ahi.sample_rate;
1291                 return pwd->ahi.header_len;
1292         }
1293         /* skip 31 bytes */
1294         if (len <= WMA_FRAME_SKIP + pwd->ahi.block_align)
1295                 return 0;
1296         ret = wma_decode_superframe(pwd, fn->buf + fn->loaded,
1297                 &out_size, (uint8_t *)inbuffer + WMA_FRAME_SKIP,
1298                 len - WMA_FRAME_SKIP);
1299         if (ret < 0)
1300                 return ret;
1301         fn->loaded += out_size;
1302         return ret + WMA_FRAME_SKIP;
1303 }
1304
1305 static void wmadec_close(struct filter_node *fn)
1306 {
1307         struct private_wmadec_data *pwd = fn->private_data;
1308         if (!pwd)
1309                 return;
1310         wmadec_cleanup(pwd);
1311         free(fn->buf);
1312         fn->buf = NULL;
1313         free(fn->private_data);
1314         fn->private_data = NULL;
1315 }
1316
1317 static void wmadec_open(struct filter_node *fn)
1318 {
1319         fn->bufsize = 1024 * 1024;
1320         fn->buf = para_malloc(fn->bufsize);
1321         fn->private_data = NULL;
1322         fn->loaded = 0;
1323 }
1324
1325 /**
1326  * The init function of the wma decoder.
1327  *
1328  * \param f Its fields are filled in by the function.
1329  */
1330 void wmadec_filter_init(struct filter *f)
1331 {
1332         f->open = wmadec_open;
1333         f->close = wmadec_close;
1334         f->convert = wmadec_convert;
1335 }