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