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 <inttypes.h>
  21 #include <stdio.h>
  22 #include <stdlib.h>
  23 #include <math.h>
  24 #include <string.h>
  25 #include <regex.h>
  26 #include <sys/select.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 "buffer_tree.h"
  35 #include "filter.h"
  36 #include "bitstream.h"
  37 #include "imdct.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         /** Information contained in the audio file header. */
  63         struct asf_header_info ahi;
  64         struct getbit_context gb;
  65         /** Whether perceptual noise is added. */
  66         int use_noise_coding;
  67         /** Depends on number of the bits per second and the frame length. */
  68         int byte_offset_bits;
  69         /** Only used if ahi->use_exp_vlc is true. */
  70         struct vlc exp_vlc;
  71         uint16_t exponent_bands[BLOCK_NB_SIZES][25];
  72         /** The index of the first coef in high band. */
  73         int high_band_start[BLOCK_NB_SIZES];
  74         /** Maximal number of coded coefficients. */
  75         int coefs_end[BLOCK_NB_SIZES];
  76         int exponent_high_sizes[BLOCK_NB_SIZES];
  77         int exponent_high_bands[BLOCK_NB_SIZES][HIGH_BAND_MAX_SIZE];
  78         struct vlc hgain_vlc;
  79
  80         /* coded values in high bands */
  81         int high_band_coded[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
  82         int high_band_values[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
  83
  84         /* there are two possible tables for spectral coefficients */
  85         struct vlc coef_vlc[2];
  86         uint16_t *run_table[2];
  87         uint16_t *level_table[2];
  88         const struct coef_vlc_table *coef_vlcs[2];
  89         /** Frame length in samples. */
  90         int frame_len;
  91         /** log2 of frame_len. */
  92         int frame_len_bits;
  93         /** Number of block sizes, one if !ahi->use_variable_block_len. */
  94         int nb_block_sizes;
  95         /* block info */
  96         int reset_block_lengths;
  97         /** log2 of current block length. */
  98         int block_len_bits;
  99         /** log2 of next block length. */
 100         int next_block_len_bits;
 101         /** log2 of previous block length. */
 102         int prev_block_len_bits;
 103         /** Block length in samples. */
 104         int block_len;
 105         /** Current position in frame. */
 106         int block_pos;
 107         /** True if mid/side stereo mode. */
 108         uint8_t ms_stereo;
 109         /** True if channel is coded. */
 110         uint8_t channel_coded[MAX_CHANNELS];
 111         /** log2 ratio frame/exp. length. */
 112         int exponents_bsize[MAX_CHANNELS];
 113
 114         float exponents[MAX_CHANNELS][BLOCK_MAX_SIZE];
 115         float max_exponent[MAX_CHANNELS];
 116         int16_t coefs1[MAX_CHANNELS][BLOCK_MAX_SIZE];
 117         float coefs[MAX_CHANNELS][BLOCK_MAX_SIZE];
 118         float output[BLOCK_MAX_SIZE * 2];
 119         struct mdct_context *mdct_ctx[BLOCK_NB_SIZES];
 120         float *windows[BLOCK_NB_SIZES];
 121         /** Output buffer for one frame and the last for IMDCT windowing. */
 122         float frame_out[MAX_CHANNELS][BLOCK_MAX_SIZE * 2];
 123         /** Last frame info. */
 124         uint8_t last_superframe[MAX_CODED_SUPERFRAME_SIZE + 4]; /* padding added */
 125         int last_bitoffset;
 126         int last_superframe_len;
 127         float noise_table[NOISE_TAB_SIZE];
 128         int noise_index;
 129         float noise_mult;       /* XXX: suppress that and integrate it in the noise array */
 130         /* lsp_to_curve tables */
 131         float lsp_cos_table[BLOCK_MAX_SIZE];
 132         float lsp_pow_e_table[256];
 133         float lsp_pow_m_table1[(1 << LSP_POW_BITS)];
 134         float lsp_pow_m_table2[(1 << LSP_POW_BITS)];
 135 };
 136
 137 #define EXPVLCBITS 8
 138 #define EXPMAX DIV_ROUND_UP(19, EXPVLCBITS)
 139
 140 #define HGAINVLCBITS 9
 141 #define HGAINMAX DIV_ROUND_UP(13, HGAINVLCBITS)
 142
 143 #define VLCBITS 9
 144 #define VLCMAX DIV_ROUND_UP(22, VLCBITS)
 145
 146 /** \cond sine_winows */
 147
 148 #define SINE_WINDOW(x) static float sine_ ## x[x] __a_aligned(16)
 149
 150 SINE_WINDOW(128);
 151 SINE_WINDOW(256);
 152 SINE_WINDOW(512);
 153 SINE_WINDOW(1024);
 154 SINE_WINDOW(2048);
 155 SINE_WINDOW(4096);
 156
 157 static float *sine_windows[6] = {
 158         sine_128, sine_256, sine_512, sine_1024, sine_2048, sine_4096
 159 };
 160 /** \endcond sine_windows */
 161
 162 /* Generate a sine window. */
 163 static void sine_window_init(float *window, int n)
 164 {
 165         int i;
 166
 167         for (i = 0; i < n; i++)
 168                 window[i] = sinf((i + 0.5) * (M_PI / (2.0 * n)));
 169 }
 170
 171 static void wmadec_cleanup(struct private_wmadec_data *pwd)
 172 {
 173         int i;
 174
 175         for (i = 0; i < pwd->nb_block_sizes; i++)
 176                 imdct_end(pwd->mdct_ctx[i]);
 177         if (pwd->ahi.use_exp_vlc)
 178                 free_vlc(&pwd->exp_vlc);
 179         if (pwd->use_noise_coding)
 180                 free_vlc(&pwd->hgain_vlc);
 181         for (i = 0; i < 2; i++) {
 182                 free_vlc(&pwd->coef_vlc[i]);
 183                 free(pwd->run_table[i]);
 184                 free(pwd->level_table[i]);
 185         }
 186 }
 187
 188 static void init_coef_vlc(struct vlc *vlc, uint16_t **prun_table,
 189                 uint16_t **plevel_table, const struct coef_vlc_table *vlc_table)
 190 {
 191         int n = vlc_table->n;
 192         const uint8_t *table_bits = vlc_table->huffbits;
 193         const uint32_t *table_codes = vlc_table->huffcodes;
 194         const uint16_t *levels_table = vlc_table->levels;
 195         uint16_t *run_table, *level_table;
 196         int i, l, j, k, level;
 197
 198         init_vlc(vlc, VLCBITS, n, table_bits, table_codes, 4);
 199
 200         run_table = para_malloc(n * sizeof(uint16_t));
 201         level_table = para_malloc(n * sizeof(uint16_t));
 202         i = 2;
 203         level = 1;
 204         k = 0;
 205         while (i < n) {
 206                 l = levels_table[k++];
 207                 for (j = 0; j < l; j++) {
 208                         run_table[i] = j;
 209                         level_table[i] = level;
 210                         i++;
 211                 }
 212                 level++;
 213         }
 214         *prun_table = run_table;
 215         *plevel_table = level_table;
 216 }
 217
 218 /* compute the scale factor band sizes for each MDCT block size */
 219 static void compute_scale_factor_band_sizes(struct private_wmadec_data *pwd,
 220         float high_freq)
 221 {
 222         struct asf_header_info *ahi = &pwd->ahi;
 223         int a, b, pos, lpos, k, block_len, i, j, n;
 224         const uint8_t *table;
 225
 226         for (k = 0; k < pwd->nb_block_sizes; k++) {
 227                 int exponent_size;
 228
 229                 block_len = pwd->frame_len >> k;
 230                 table = NULL;
 231                 a = pwd->frame_len_bits - BLOCK_MIN_BITS - k;
 232                 if (a < 3) {
 233                         if (ahi->sample_rate >= 44100)
 234                                 table = exponent_band_44100[a];
 235                         else if (ahi->sample_rate >= 32000)
 236                                 table = exponent_band_32000[a];
 237                         else if (ahi->sample_rate >= 22050)
 238                                 table = exponent_band_22050[a];
 239                 }
 240                 if (table) {
 241                         n = *table++;
 242                         for (i = 0; i < n; i++)
 243                                 pwd->exponent_bands[k][i] = table[i];
 244                         exponent_size = n;
 245                 } else {
 246                         j = 0;
 247                         lpos = 0;
 248                         for (i = 0; i < 25; i++) {
 249                                 a = wma_critical_freqs[i];
 250                                 b = ahi->sample_rate;
 251                                 pos = ((block_len * 2 * a) + (b << 1)) / (4 * b);
 252                                 pos <<= 2;
 253                                 if (pos > block_len)
 254                                         pos = block_len;
 255                                 if (pos > lpos)
 256                                         pwd->exponent_bands[k][j++] = pos - lpos;
 257                                 if (pos >= block_len)
 258                                         break;
 259                                 lpos = pos;
 260                         }
 261                         exponent_size = j;
 262                 }
 263
 264                 /* max number of coefs */
 265                 pwd->coefs_end[k] = (pwd->frame_len - ((pwd->frame_len * 9) / 100)) >> k;
 266                 /* high freq computation */
 267                 pwd->high_band_start[k] = (int) ((block_len * 2 * high_freq)
 268                         / ahi->sample_rate + 0.5);
 269                 n = exponent_size;
 270                 j = 0;
 271                 pos = 0;
 272                 for (i = 0; i < n; i++) {
 273                         int start, end;
 274                         start = pos;
 275                         pos += pwd->exponent_bands[k][i];
 276                         end = pos;
 277                         if (start < pwd->high_band_start[k])
 278                                 start = pwd->high_band_start[k];
 279                         if (end > pwd->coefs_end[k])
 280                                 end = pwd->coefs_end[k];
 281                         if (end > start)
 282                                 pwd->exponent_high_bands[k][j++] = end - start;
 283                 }
 284                 pwd->exponent_high_sizes[k] = j;
 285         }
 286 }
 287
 288 static int wma_init(struct private_wmadec_data *pwd)
 289 {
 290         int i;
 291         float bps1, high_freq;
 292         volatile float bps;
 293         int sample_rate1;
 294         int coef_vlc_table;
 295         struct asf_header_info *ahi = &pwd->ahi;
 296         int flags2 = ahi->flags2;
 297
 298         if (ahi->sample_rate <= 0 || ahi->sample_rate > 50000
 299                 || ahi->channels <= 0 || ahi->channels > 8
 300                 || ahi->bit_rate <= 0)
 301                 return -E_WMA_BAD_PARAMS;
 302
 303         /* compute MDCT block size */
 304         if (ahi->sample_rate <= 16000)
 305                 pwd->frame_len_bits = 9;
 306         else if (ahi->sample_rate <= 22050)
 307                 pwd->frame_len_bits = 10;
 308         else
 309                 pwd->frame_len_bits = 11;
 310         pwd->frame_len = 1 << pwd->frame_len_bits;
 311         if (pwd->ahi.use_variable_block_len) {
 312                 int nb_max, nb;
 313                 nb = ((flags2 >> 3) & 3) + 1;
 314                 if ((ahi->bit_rate / ahi->channels) >= 32000)
 315                         nb += 2;
 316                 nb_max = pwd->frame_len_bits - BLOCK_MIN_BITS;
 317                 if (nb > nb_max)
 318                         nb = nb_max;
 319                 pwd->nb_block_sizes = nb + 1;
 320         } else
 321                 pwd->nb_block_sizes = 1;
 322
 323         /* init rate dependent parameters */
 324         pwd->use_noise_coding = 1;
 325         high_freq = ahi->sample_rate * 0.5;
 326
 327         /* wma2 rates are normalized */
 328         sample_rate1 = ahi->sample_rate;
 329         if (sample_rate1 >= 44100)
 330                 sample_rate1 = 44100;
 331         else if (sample_rate1 >= 22050)
 332                 sample_rate1 = 22050;
 333         else if (sample_rate1 >= 16000)
 334                 sample_rate1 = 16000;
 335         else if (sample_rate1 >= 11025)
 336                 sample_rate1 = 11025;
 337         else if (sample_rate1 >= 8000)
 338                 sample_rate1 = 8000;
 339
 340         bps = (float) ahi->bit_rate / (float) (ahi->channels * ahi->sample_rate);
 341         pwd->byte_offset_bits = wma_log2((int) (bps * pwd->frame_len / 8.0 + 0.5)) + 2;
 342         /*
 343          * Compute high frequency value and choose if noise coding should be
 344          * activated.
 345          */
 346         bps1 = bps;
 347         if (ahi->channels == 2)
 348                 bps1 = bps * 1.6;
 349         if (sample_rate1 == 44100) {
 350                 if (bps1 >= 0.61)
 351                         pwd->use_noise_coding = 0;
 352                 else
 353                         high_freq = high_freq * 0.4;
 354         } else if (sample_rate1 == 22050) {
 355                 if (bps1 >= 1.16)
 356                         pwd->use_noise_coding = 0;
 357                 else if (bps1 >= 0.72)
 358                         high_freq = high_freq * 0.7;
 359                 else
 360                         high_freq = high_freq * 0.6;
 361         } else if (sample_rate1 == 16000) {
 362                 if (bps > 0.5)
 363                         high_freq = high_freq * 0.5;
 364                 else
 365                         high_freq = high_freq * 0.3;
 366         } else if (sample_rate1 == 11025)
 367                 high_freq = high_freq * 0.7;
 368         else if (sample_rate1 == 8000) {
 369                 if (bps <= 0.625)
 370                         high_freq = high_freq * 0.5;
 371                 else if (bps > 0.75)
 372                         pwd->use_noise_coding = 0;
 373                 else
 374                         high_freq = high_freq * 0.65;
 375         } else {
 376                 if (bps >= 0.8)
 377                         high_freq = high_freq * 0.75;
 378                 else if (bps >= 0.6)
 379                         high_freq = high_freq * 0.6;
 380                 else
 381                         high_freq = high_freq * 0.5;
 382         }
 383         PARA_INFO_LOG("channels=%d sample_rate=%d "
 384                 "bitrate=%d block_align=%d\n",
 385                 ahi->channels, ahi->sample_rate,
 386                 ahi->bit_rate, ahi->block_align);
 387         PARA_INFO_LOG("frame_len=%d, bps=%f bps1=%f "
 388                 "high_freq=%f bitoffset=%d\n",
 389                 pwd->frame_len, bps, bps1,
 390                 high_freq, pwd->byte_offset_bits);
 391         PARA_INFO_LOG("use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n",
 392                 pwd->use_noise_coding, pwd->ahi.use_exp_vlc, pwd->nb_block_sizes);
 393
 394         compute_scale_factor_band_sizes(pwd, high_freq);
 395         /* init MDCT windows : simple sinus window */
 396         for (i = 0; i < pwd->nb_block_sizes; i++) {
 397                 int n;
 398                 n = 1 << (pwd->frame_len_bits - i);
 399                 sine_window_init(sine_windows[pwd->frame_len_bits - i - 7], n);
 400                 pwd->windows[i] = sine_windows[pwd->frame_len_bits - i - 7];
 401         }
 402
 403         pwd->reset_block_lengths = 1;
 404
 405         if (pwd->use_noise_coding) {
 406                 /* init the noise generator */
 407                 if (pwd->ahi.use_exp_vlc)
 408                         pwd->noise_mult = 0.02;
 409                 else
 410                         pwd->noise_mult = 0.04;
 411
 412                 {
 413                         unsigned int seed;
 414                         float norm;
 415                         seed = 1;
 416                         norm = (1.0 / (float) (1LL << 31)) * sqrt(3) * pwd->noise_mult;
 417                         for (i = 0; i < NOISE_TAB_SIZE; i++) {
 418                                 seed = seed * 314159 + 1;
 419                                 pwd->noise_table[i] = (float) ((int) seed) * norm;
 420                         }
 421                 }
 422         }
 423
 424         /* choose the VLC tables for the coefficients */
 425         coef_vlc_table = 2;
 426         if (ahi->sample_rate >= 32000) {
 427                 if (bps1 < 0.72)
 428                         coef_vlc_table = 0;
 429                 else if (bps1 < 1.16)
 430                         coef_vlc_table = 1;
 431         }
 432         pwd->coef_vlcs[0] = &coef_vlcs[coef_vlc_table * 2];
 433         pwd->coef_vlcs[1] = &coef_vlcs[coef_vlc_table * 2 + 1];
 434         init_coef_vlc(&pwd->coef_vlc[0], &pwd->run_table[0], &pwd->level_table[0],
 435                 pwd->coef_vlcs[0]);
 436         init_coef_vlc(&pwd->coef_vlc[1], &pwd->run_table[1], &pwd->level_table[1],
 437                 pwd->coef_vlcs[1]);
 438         return 0;
 439 }
 440
 441 static void wma_lsp_to_curve_init(struct private_wmadec_data *pwd, int frame_len)
 442 {
 443         float wdel, a, b;
 444         int i, e, m;
 445
 446         wdel = M_PI / frame_len;
 447         for (i = 0; i < frame_len; i++)
 448                 pwd->lsp_cos_table[i] = 2.0f * cos(wdel * i);
 449
 450         /* tables for x^-0.25 computation */
 451         for (i = 0; i < 256; i++) {
 452                 e = i - 126;
 453                 pwd->lsp_pow_e_table[i] = pow(2.0, e * -0.25);
 454         }
 455
 456         /* These two tables are needed to avoid two operations in pow_m1_4. */
 457         b = 1.0;
 458         for (i = (1 << LSP_POW_BITS) - 1; i >= 0; i--) {
 459                 m = (1 << LSP_POW_BITS) + i;
 460                 a = (float) m *(0.5 / (1 << LSP_POW_BITS));
 461                 a = pow(a, -0.25);
 462                 pwd->lsp_pow_m_table1[i] = 2 * a - b;
 463                 pwd->lsp_pow_m_table2[i] = b - a;
 464                 b = a;
 465         }
 466 }
 467
 468 static int wma_decode_init(char *initial_buf, int len, struct private_wmadec_data **result)
 469 {
 470         struct private_wmadec_data *pwd;
 471         int ret, i;
 472
 473         PARA_NOTICE_LOG("initial buf: %d bytes\n", len);
 474         pwd = para_calloc(sizeof(*pwd));
 475         ret = read_asf_header(initial_buf, len, &pwd->ahi);
 476         if (ret <= 0) {
 477                 free(pwd);
 478                 return ret;
 479         }
 480
 481         ret = wma_init(pwd);
 482         if (ret < 0)
 483                 return ret;
 484         /* init MDCT */
 485         for (i = 0; i < pwd->nb_block_sizes; i++) {
 486                 ret = imdct_init(pwd->frame_len_bits - i + 1, &pwd->mdct_ctx[i]);
 487                 if (ret < 0)
 488                         return ret;
 489         }
 490         if (pwd->use_noise_coding) {
 491                 PARA_INFO_LOG("using noise coding\n");
 492                 init_vlc(&pwd->hgain_vlc, HGAINVLCBITS,
 493                         sizeof(wma_hgain_huffbits), wma_hgain_huffbits,
 494                         wma_hgain_huffcodes, 2);
 495         }
 496
 497         if (pwd->ahi.use_exp_vlc) {
 498                 PARA_INFO_LOG("using exp_vlc\n");
 499                 init_vlc(&pwd->exp_vlc, EXPVLCBITS, sizeof(wma_scale_huffbits),
 500                         wma_scale_huffbits, wma_scale_huffcodes, 4);
 501         } else {
 502                 PARA_INFO_LOG("using curve\n");
 503                 wma_lsp_to_curve_init(pwd, pwd->frame_len);
 504         }
 505         *result = pwd;
 506         return pwd->ahi.header_len;
 507 }
 508
 509 /**
 510  * compute x^-0.25 with an exponent and mantissa table. We use linear
 511  * interpolation to reduce the mantissa table size at a small speed
 512  * expense (linear interpolation approximately doubles the number of
 513  * bits of precision).
 514  */
 515 static inline float pow_m1_4(struct private_wmadec_data *pwd, float x)
 516 {
 517         union {
 518                 float f;
 519                 unsigned int v;
 520         } u, t;
 521         unsigned int e, m;
 522         float a, b;
 523
 524         u.f = x;
 525         e = u.v >> 23;
 526         m = (u.v >> (23 - LSP_POW_BITS)) & ((1 << LSP_POW_BITS) - 1);
 527         /* build interpolation scale: 1 <= t < 2. */
 528         t.v = ((u.v << LSP_POW_BITS) & ((1 << 23) - 1)) | (127 << 23);
 529         a = pwd->lsp_pow_m_table1[m];
 530         b = pwd->lsp_pow_m_table2[m];
 531         return pwd->lsp_pow_e_table[e] * (a + b * t.f);
 532 }
 533
 534 static void wma_lsp_to_curve(struct private_wmadec_data *pwd,
 535                 float *out, float *val_max_ptr, int n, float *lsp)
 536 {
 537         int i, j;
 538         float p, q, w, v, val_max;
 539
 540         val_max = 0;
 541         for (i = 0; i < n; i++) {
 542                 p = 0.5f;
 543                 q = 0.5f;
 544                 w = pwd->lsp_cos_table[i];
 545                 for (j = 1; j < NB_LSP_COEFS; j += 2) {
 546                         q *= w - lsp[j - 1];
 547                         p *= w - lsp[j];
 548                 }
 549                 p *= p * (2.0f - w);
 550                 q *= q * (2.0f + w);
 551                 v = p + q;
 552                 v = pow_m1_4(pwd, v);
 553                 if (v > val_max)
 554                         val_max = v;
 555                 out[i] = v;
 556         }
 557         *val_max_ptr = val_max;
 558 }
 559
 560 /* Decode exponents coded with LSP coefficients (same idea as Vorbis). */
 561 static void decode_exp_lsp(struct private_wmadec_data *pwd, int ch)
 562 {
 563         float lsp_coefs[NB_LSP_COEFS];
 564         int val, i;
 565
 566         for (i = 0; i < NB_LSP_COEFS; i++) {
 567                 if (i == 0 || i >= 8)
 568                         val = get_bits(&pwd->gb, 3);
 569                 else
 570                         val = get_bits(&pwd->gb, 4);
 571                 lsp_coefs[i] = wma_lsp_codebook[i][val];
 572         }
 573
 574         wma_lsp_to_curve(pwd, pwd->exponents[ch], &pwd->max_exponent[ch],
 575                 pwd->block_len, lsp_coefs);
 576 }
 577
 578 /* Decode exponents coded with VLC codes. */
 579 static int decode_exp_vlc(struct private_wmadec_data *pwd, 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 = pwd->exponent_bands[pwd->frame_len_bits - pwd->block_len_bits];
 586         ptr = band_ptr;
 587         q = pwd->exponents[ch];
 588         q_end = q + pwd->block_len;
 589         max_scale = 0;
 590         last_exp = 36;
 591
 592         while (q < q_end) {
 593                 code = get_vlc(&pwd->gb, pwd->exp_vlc.table, EXPVLCBITS, EXPMAX);
 594                 if (code < 0)
 595                         return code;
 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         pwd->max_exponent[ch] = max_scale;
 608         return 0;
 609 }
 610
 611 /* compute src0 * src1 + src2 */
 612 static inline void vector_mult_add(float *dst, const float *src0, const float *src1,
 613                 const float *src2, int len)
 614 {
 615         int i;
 616
 617         for (i = 0; i < len; i++)
 618                 dst[i] = src0[i] * src1[i] + src2[i];
 619 }
 620
 621 static inline void vector_mult_reverse(float *dst, const float *src0,
 622                 const float *src1, int len)
 623 {
 624         int i;
 625
 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 *pwd, float *out)
 638 {
 639         float *in = pwd->output;
 640         int block_len, bsize, n;
 641
 642         /* left part */
 643         if (pwd->block_len_bits <= pwd->prev_block_len_bits) {
 644                 block_len = pwd->block_len;
 645                 bsize = pwd->frame_len_bits - pwd->block_len_bits;
 646                 vector_mult_add(out, in, pwd->windows[bsize], out, block_len);
 647         } else {
 648                 block_len = 1 << pwd->prev_block_len_bits;
 649                 n = (pwd->block_len - block_len) / 2;
 650                 bsize = pwd->frame_len_bits - pwd->prev_block_len_bits;
 651                 vector_mult_add(out + n, in + n, pwd->windows[bsize], out + n,
 652                         block_len);
 653                 memcpy(out + n + block_len, in + n + block_len,
 654                         n * sizeof(float));
 655         }
 656         out += pwd->block_len;
 657         in += pwd->block_len;
 658         /* right part */
 659         if (pwd->block_len_bits <= pwd->next_block_len_bits) {
 660                 block_len = pwd->block_len;
 661                 bsize = pwd->frame_len_bits - pwd->block_len_bits;
 662                 vector_mult_reverse(out, in, pwd->windows[bsize], block_len);
 663         } else {
 664                 block_len = 1 << pwd->next_block_len_bits;
 665                 n = (pwd->block_len - block_len) / 2;
 666                 bsize = pwd->frame_len_bits - pwd->next_block_len_bits;
 667                 memcpy(out, in, n * sizeof(float));
 668                 vector_mult_reverse(out + n, in + n, pwd->windows[bsize],
 669                         block_len);
 670                 memset(out + n + block_len, 0, n * sizeof(float));
 671         }
 672 }
 673
 674 static int wma_total_gain_to_bits(int total_gain)
 675 {
 676         if (total_gain < 15)
 677                 return 13;
 678         else if (total_gain < 32)
 679                 return 12;
 680         else if (total_gain < 40)
 681                 return 11;
 682         else if (total_gain < 45)
 683                 return 10;
 684         else
 685                 return 9;
 686 }
 687
 688 static int compute_high_band_values(struct private_wmadec_data *pwd,
 689                 int bsize, int nb_coefs[MAX_CHANNELS])
 690 {
 691         int ch;
 692
 693         if (!pwd->use_noise_coding)
 694                 return 0;
 695         for (ch = 0; ch < pwd->ahi.channels; ch++) {
 696                 int i, m, a;
 697                 if (!pwd->channel_coded[ch])
 698                         continue;
 699                 m = pwd->exponent_high_sizes[bsize];
 700                 for (i = 0; i < m; i++) {
 701                         a = get_bit(&pwd->gb);
 702                         pwd->high_band_coded[ch][i] = a;
 703                         if (!a)
 704                                 continue;
 705                         nb_coefs[ch] -= pwd->exponent_high_bands[bsize][i];
 706                 }
 707         }
 708         for (ch = 0; ch < pwd->ahi.channels; ch++) {
 709                 int i, n, val;
 710                 if (!pwd->channel_coded[ch])
 711                         continue;
 712                 n = pwd->exponent_high_sizes[bsize];
 713                 val = (int)0x80000000;
 714                 for (i = 0; i < n; i++) {
 715                         if (!pwd->high_band_coded[ch][i])
 716                                 continue;
 717                         if (val == (int)0x80000000)
 718                                 val = get_bits(&pwd->gb, 7) - 19;
 719                         else {
 720                                 int code = get_vlc(&pwd->gb,
 721                                         pwd->hgain_vlc.table, HGAINVLCBITS,
 722                                         HGAINMAX);
 723                                 if (code < 0)
 724                                         return code;
 725                                 val += code - 18;
 726                         }
 727                         pwd->high_band_values[ch][i] = val;
 728                 }
 729         }
 730         return 1;
 731 }
 732
 733 static void compute_mdct_coefficients(struct private_wmadec_data *pwd,
 734                 int bsize, int total_gain, int nb_coefs[MAX_CHANNELS])
 735 {
 736         int ch;
 737         float mdct_norm = 1.0 / (pwd->block_len / 2);
 738
 739         for (ch = 0; ch < pwd->ahi.channels; ch++) {
 740                 int16_t *coefs1;
 741                 float *coefs, *exponents, mult, mult1, noise;
 742                 int i, j, n, n1, last_high_band, esize;
 743                 float exp_power[HIGH_BAND_MAX_SIZE];
 744
 745                 if (!pwd->channel_coded[ch])
 746                         continue;
 747                 coefs1 = pwd->coefs1[ch];
 748                 exponents = pwd->exponents[ch];
 749                 esize = pwd->exponents_bsize[ch];
 750                 mult = pow(10, total_gain * 0.05) / pwd->max_exponent[ch];
 751                 mult *= mdct_norm;
 752                 coefs = pwd->coefs[ch];
 753                 if (!pwd->use_noise_coding) {
 754                         /* XXX: optimize more */
 755                         n = nb_coefs[ch];
 756                         for (i = 0; i < n; i++)
 757                                 *coefs++ = coefs1[i] *
 758                                         exponents[i << bsize >> esize] * mult;
 759                         n = pwd->block_len - pwd->coefs_end[bsize];
 760                         for (i = 0; i < n; i++)
 761                                 *coefs++ = 0.0;
 762                         continue;
 763                 }
 764                 n1 = pwd->exponent_high_sizes[bsize];
 765                 /* compute power of high bands */
 766                 exponents = pwd->exponents[ch] +
 767                         (pwd->high_band_start[bsize] << bsize);
 768                 last_high_band = 0; /* avoid warning */
 769                 for (j = 0; j < n1; j++) {
 770                         n = pwd->exponent_high_bands[
 771                                 pwd->frame_len_bits - pwd->block_len_bits][j];
 772                         if (pwd->high_band_coded[ch][j]) {
 773                                 float e2, val;
 774                                 e2 = 0;
 775                                 for (i = 0; i < n; i++) {
 776                                         val = exponents[i << bsize >> esize];
 777                                         e2 += val * val;
 778                                 }
 779                                 exp_power[j] = e2 / n;
 780                                 last_high_band = j;
 781                         }
 782                         exponents += n << bsize;
 783                 }
 784                 /* main freqs and high freqs */
 785                 exponents = pwd->exponents[ch];
 786                 for (j = -1; j < n1; j++) {
 787                         if (j < 0)
 788                                 n = pwd->high_band_start[bsize];
 789                         else
 790                                 n = pwd->exponent_high_bands[pwd->frame_len_bits
 791                                         - pwd->block_len_bits][j];
 792                         if (j >= 0 && pwd->high_band_coded[ch][j]) {
 793                                 /* use noise with specified power */
 794                                 mult1 = sqrt(exp_power[j]
 795                                         / exp_power[last_high_band]);
 796                                 /* XXX: use a table */
 797                                 mult1 *= pow(10, pwd->high_band_values[ch][j] * 0.05);
 798                                 mult1 /= (pwd->max_exponent[ch] * pwd->noise_mult);
 799                                 mult1 *= mdct_norm;
 800                                 for (i = 0; i < n; i++) {
 801                                         noise = pwd->noise_table[pwd->noise_index];
 802                                         pwd->noise_index = (pwd->noise_index + 1)
 803                                                 & (NOISE_TAB_SIZE - 1);
 804                                         *coefs++ = noise * exponents[
 805                                                 i << bsize >> esize] * mult1;
 806                                 }
 807                                 exponents += n << bsize;
 808                         } else {
 809                                 /* coded values + small noise */
 810                                 for (i = 0; i < n; i++) {
 811                                         noise = pwd->noise_table[pwd->noise_index];
 812                                         pwd->noise_index = (pwd->noise_index + 1)
 813                                                 & (NOISE_TAB_SIZE - 1);
 814                                         *coefs++ = ((*coefs1++) + noise) *
 815                                                 exponents[i << bsize >> esize]
 816                                                 * mult;
 817                                 }
 818                                 exponents += n << bsize;
 819                         }
 820                 }
 821                 /* very high freqs: noise */
 822                 n = pwd->block_len - pwd->coefs_end[bsize];
 823                 mult1 = mult * exponents[((-1 << bsize)) >> esize];
 824                 for (i = 0; i < n; i++) {
 825                         *coefs++ = pwd->noise_table[pwd->noise_index] * mult1;
 826                         pwd->noise_index = (pwd->noise_index + 1)
 827                                 & (NOISE_TAB_SIZE - 1);
 828                 }
 829         }
 830 }
 831
 832 /**
 833  * Returns 0 if OK, 1 if last block of frame, negative on uncorrectable
 834  * errors.
 835  */
 836 static int wma_decode_block(struct private_wmadec_data *pwd)
 837 {
 838         int ret, n, v, ch, code, bsize;
 839         int coef_nb_bits, total_gain;
 840         int nb_coefs[MAX_CHANNELS];
 841
 842         /* compute current block length */
 843         if (pwd->ahi.use_variable_block_len) {
 844                 n = wma_log2(pwd->nb_block_sizes - 1) + 1;
 845
 846                 if (pwd->reset_block_lengths) {
 847                         pwd->reset_block_lengths = 0;
 848                         v = get_bits(&pwd->gb, n);
 849                         if (v >= pwd->nb_block_sizes)
 850                                 return -E_WMA_BLOCK_SIZE;
 851                         pwd->prev_block_len_bits = pwd->frame_len_bits - v;
 852                         v = get_bits(&pwd->gb, n);
 853                         if (v >= pwd->nb_block_sizes)
 854                                 return -E_WMA_BLOCK_SIZE;
 855                         pwd->block_len_bits = pwd->frame_len_bits - v;
 856                 } else {
 857                         /* update block lengths */
 858                         pwd->prev_block_len_bits = pwd->block_len_bits;
 859                         pwd->block_len_bits = pwd->next_block_len_bits;
 860                 }
 861                 v = get_bits(&pwd->gb, n);
 862                 if (v >= pwd->nb_block_sizes)
 863                         return -E_WMA_BLOCK_SIZE;
 864                 pwd->next_block_len_bits = pwd->frame_len_bits - v;
 865         } else {
 866                 /* fixed block len */
 867                 pwd->next_block_len_bits = pwd->frame_len_bits;
 868                 pwd->prev_block_len_bits = pwd->frame_len_bits;
 869                 pwd->block_len_bits = pwd->frame_len_bits;
 870         }
 871
 872         /* now check if the block length is coherent with the frame length */
 873         pwd->block_len = 1 << pwd->block_len_bits;
 874         if ((pwd->block_pos + pwd->block_len) > pwd->frame_len)
 875                 return -E_INCOHERENT_BLOCK_LEN;
 876
 877         if (pwd->ahi.channels == 2)
 878                 pwd->ms_stereo = get_bit(&pwd->gb);
 879         v = 0;
 880         for (ch = 0; ch < pwd->ahi.channels; ch++) {
 881                 int a = get_bit(&pwd->gb);
 882                 pwd->channel_coded[ch] = a;
 883                 v |= a;
 884         }
 885
 886         bsize = pwd->frame_len_bits - pwd->block_len_bits;
 887
 888         /* if no channel coded, no need to go further */
 889         /* XXX: fix potential framing problems */
 890         if (!v)
 891                 goto next;
 892
 893         /*
 894          * Read total gain and extract corresponding number of bits for coef
 895          * escape coding.
 896          */
 897         total_gain = 1;
 898         for (;;) {
 899                 int a = get_bits(&pwd->gb, 7);
 900                 total_gain += a;
 901                 if (a != 127)
 902                         break;
 903         }
 904
 905         coef_nb_bits = wma_total_gain_to_bits(total_gain);
 906
 907         /* compute number of coefficients */
 908         n = pwd->coefs_end[bsize];
 909         for (ch = 0; ch < pwd->ahi.channels; ch++)
 910                 nb_coefs[ch] = n;
 911
 912         ret = compute_high_band_values(pwd, bsize, nb_coefs);
 913         if (ret < 0)
 914                 return ret;
 915
 916         /* exponents can be reused in short blocks. */
 917         if ((pwd->block_len_bits == pwd->frame_len_bits) || get_bit(&pwd->gb)) {
 918                 for (ch = 0; ch < pwd->ahi.channels; ch++) {
 919                         if (pwd->channel_coded[ch]) {
 920                                 if (pwd->ahi.use_exp_vlc) {
 921                                         ret = decode_exp_vlc(pwd, ch);
 922                                         if (ret < 0)
 923                                                 return ret;
 924                                 } else
 925                                         decode_exp_lsp(pwd, ch);
 926                                 pwd->exponents_bsize[ch] = bsize;
 927                         }
 928                 }
 929         }
 930
 931         /* parse spectral coefficients : just RLE encoding */
 932         for (ch = 0; ch < pwd->ahi.channels; ch++) {
 933                 struct vlc *coef_vlc;
 934                 int level, run, tindex;
 935                 int16_t *ptr, *eptr;
 936                 const uint16_t *level_table, *run_table;
 937
 938                 if (!pwd->channel_coded[ch])
 939                         continue;
 940                 /*
 941                  * special VLC tables are used for ms stereo because there is
 942                  * potentially less energy there
 943                  */
 944                 tindex = (ch == 1 && pwd->ms_stereo);
 945                 coef_vlc = &pwd->coef_vlc[tindex];
 946                 run_table = pwd->run_table[tindex];
 947                 level_table = pwd->level_table[tindex];
 948                 /* XXX: optimize */
 949                 ptr = &pwd->coefs1[ch][0];
 950                 eptr = ptr + nb_coefs[ch];
 951                 memset(ptr, 0, pwd->block_len * sizeof(int16_t));
 952                 for (;;) {
 953                         code = get_vlc(&pwd->gb, coef_vlc->table,
 954                                 VLCBITS, VLCMAX);
 955                         if (code < 0)
 956                                 return code;
 957                         if (code == 1) /* EOB */
 958                                 break;
 959                         if (code == 0) { /* escape */
 960                                 level = get_bits(&pwd->gb, coef_nb_bits);
 961                                 /* reading block_len_bits would be better */
 962                                 run = get_bits(&pwd->gb, pwd->frame_len_bits);
 963                         } else { /* normal code */
 964                                 run = run_table[code];
 965                                 level = level_table[code];
 966                         }
 967                         if (!get_bit(&pwd->gb))
 968                                 level = -level;
 969                         ptr += run;
 970                         if (ptr >= eptr) {
 971                                 PARA_ERROR_LOG("overflow in spectral RLE, ignoring\n");
 972                                 break;
 973                         }
 974                         *ptr++ = level;
 975                         if (ptr >= eptr) /* EOB can be omitted */
 976                                 break;
 977                 }
 978         }
 979         compute_mdct_coefficients(pwd, bsize, total_gain, nb_coefs);
 980         if (pwd->ms_stereo && pwd->channel_coded[1]) {
 981                 float a, b;
 982                 int i;
 983                 /*
 984                  * Nominal case for ms stereo: we do it before mdct.
 985                  *
 986                  * No need to optimize this case because it should almost never
 987                  * happen.
 988                  */
 989                 if (!pwd->channel_coded[0]) {
 990                         PARA_NOTICE_LOG("rare ms-stereo\n");
 991                         memset(pwd->coefs[0], 0, sizeof(float) * pwd->block_len);
 992                         pwd->channel_coded[0] = 1;
 993                 }
 994                 for (i = 0; i < pwd->block_len; i++) {
 995                         a = pwd->coefs[0][i];
 996                         b = pwd->coefs[1][i];
 997                         pwd->coefs[0][i] = a + b;
 998                         pwd->coefs[1][i] = a - b;
 999                 }
1000         }
1001 next:
1002         for (ch = 0; ch < pwd->ahi.channels; ch++) {
1003                 int n4, idx;
1004
1005                 n4 = pwd->block_len / 2;
1006                 if (pwd->channel_coded[ch])
1007                         imdct(pwd->mdct_ctx[bsize], pwd->output, pwd->coefs[ch]);
1008                 else if (!(pwd->ms_stereo && ch == 1))
1009                         memset(pwd->output, 0, sizeof(pwd->output));
1010
1011                 /* multiply by the window and add in the frame */
1012                 idx = (pwd->frame_len / 2) + pwd->block_pos - n4;
1013                 wma_window(pwd, &pwd->frame_out[ch][idx]);
1014         }
1015
1016         /* update block number */
1017         pwd->block_pos += pwd->block_len;
1018         if (pwd->block_pos >= pwd->frame_len)
1019                 return 1;
1020         else
1021                 return 0;
1022 }
1023
1024 /*
1025  * Clip a signed integer value into the -32768,32767 range.
1026  *
1027  * \param a The value to clip.
1028  *
1029  * \return The clipped value.
1030  */
1031 static inline int16_t av_clip_int16(int a)
1032 {
1033         if ((a + 32768) & ~65535)
1034                 return (a >> 31) ^ 32767;
1035         else
1036                 return a;
1037 }
1038
1039 /* Decode a frame of frame_len samples. */
1040 static int wma_decode_frame(struct private_wmadec_data *pwd, int16_t *samples)
1041 {
1042         int ret, i, n, ch, incr;
1043         int16_t *ptr;
1044         float *iptr;
1045
1046         /* read each block */
1047         pwd->block_pos = 0;
1048         for (;;) {
1049                 ret = wma_decode_block(pwd);
1050                 if (ret < 0)
1051                         return ret;
1052                 if (ret)
1053                         break;
1054         }
1055
1056         /* convert frame to integer */
1057         n = pwd->frame_len;
1058         incr = pwd->ahi.channels;
1059         for (ch = 0; ch < pwd->ahi.channels; ch++) {
1060                 ptr = samples + ch;
1061                 iptr = pwd->frame_out[ch];
1062
1063                 for (i = 0; i < n; i++) {
1064                         *ptr = av_clip_int16(lrintf(*iptr++));
1065                         ptr += incr;
1066                 }
1067                 /* prepare for next block */
1068                 memmove(&pwd->frame_out[ch][0], &pwd->frame_out[ch][pwd->frame_len],
1069                         pwd->frame_len * sizeof(float));
1070         }
1071         return 0;
1072 }
1073
1074 static int wma_decode_superframe(struct private_wmadec_data *pwd, void *data,
1075                 int *data_size, const uint8_t *buf, int buf_size)
1076 {
1077         int ret;
1078         int16_t *samples;
1079
1080         if (buf_size == 0) {
1081                 pwd->last_superframe_len = 0;
1082                 return 0;
1083         }
1084         if (buf_size < pwd->ahi.block_align)
1085                 return 0;
1086         buf_size = pwd->ahi.block_align;
1087         samples = data;
1088         init_get_bits(&pwd->gb, buf, buf_size);
1089         if (pwd->ahi.use_bit_reservoir) {
1090                 int i, nb_frames, bit_offset, pos, len;
1091                 uint8_t *q;
1092
1093                 /* read super frame header */
1094                 skip_bits(&pwd->gb, 4); /* super frame index */
1095                 nb_frames = get_bits(&pwd->gb, 4) - 1;
1096                 // PARA_DEBUG_LOG("have %d frames\n", nb_frames);
1097                 ret = -E_WMA_OUTPUT_SPACE;
1098                 if ((nb_frames + 1) * pwd->ahi.channels * pwd->frame_len
1099                                 * sizeof(int16_t) > *data_size)
1100                         goto fail;
1101
1102                 bit_offset = get_bits(&pwd->gb, pwd->byte_offset_bits + 3);
1103
1104                 if (pwd->last_superframe_len > 0) {
1105                         /* add bit_offset bits to last frame */
1106                         ret = -E_WMA_BAD_SUPERFRAME;
1107                         if ((pwd->last_superframe_len + ((bit_offset + 7) >> 3)) >
1108                                         MAX_CODED_SUPERFRAME_SIZE)
1109                                 goto fail;
1110                         q = pwd->last_superframe + pwd->last_superframe_len;
1111                         len = bit_offset;
1112                         while (len > 7) {
1113                                 *q++ = get_bits(&pwd->gb, 8);
1114                                 len -= 8;
1115                         }
1116                         if (len > 0)
1117                                 *q++ = get_bits(&pwd->gb, len) << (8 - len);
1118
1119                         /* XXX: bit_offset bits into last frame */
1120                         init_get_bits(&pwd->gb, pwd->last_superframe,
1121                                 MAX_CODED_SUPERFRAME_SIZE);
1122                         /* skip unused bits */
1123                         if (pwd->last_bitoffset > 0)
1124                                 skip_bits(&pwd->gb, pwd->last_bitoffset);
1125                         /*
1126                          * This frame is stored in the last superframe and in
1127                          * the current one.
1128                          */
1129                         ret = wma_decode_frame(pwd, samples);
1130                         if (ret < 0)
1131                                 goto fail;
1132                         samples += pwd->ahi.channels * pwd->frame_len;
1133                 }
1134
1135                 /* read each frame starting from bit_offset */
1136                 pos = bit_offset + 4 + 4 + pwd->byte_offset_bits + 3;
1137                 init_get_bits(&pwd->gb, buf + (pos >> 3),
1138                         (MAX_CODED_SUPERFRAME_SIZE - (pos >> 3)));
1139                 len = pos & 7;
1140                 if (len > 0)
1141                         skip_bits(&pwd->gb, len);
1142
1143                 pwd->reset_block_lengths = 1;
1144                 for (i = 0; i < nb_frames; i++) {
1145                         ret = wma_decode_frame(pwd, samples);
1146                         if (ret < 0)
1147                                 goto fail;
1148                         samples += pwd->ahi.channels * pwd->frame_len;
1149                 }
1150
1151                 /* we copy the end of the frame in the last frame buffer */
1152                 pos = get_bits_count(&pwd->gb) +
1153                         ((bit_offset + 4 + 4 + pwd->byte_offset_bits + 3) & ~7);
1154                 pwd->last_bitoffset = pos & 7;
1155                 pos >>= 3;
1156                 len = buf_size - pos;
1157                 ret = -E_WMA_BAD_SUPERFRAME;
1158                 if (len > MAX_CODED_SUPERFRAME_SIZE || len < 0)
1159                         goto fail;
1160                 pwd->last_superframe_len = len;
1161                 memcpy(pwd->last_superframe, buf + pos, len);
1162         } else {
1163                 PARA_DEBUG_LOG("not using bit reservoir\n");
1164                 ret = -E_WMA_OUTPUT_SPACE;
1165                 if (pwd->ahi.channels * pwd->frame_len * sizeof(int16_t) > *data_size)
1166                         goto fail;
1167                 /* single frame decode */
1168                 ret = wma_decode_frame(pwd, samples);
1169                 if (ret < 0)
1170                         goto fail;
1171                 samples += pwd->ahi.channels * pwd->frame_len;
1172         }
1173         PARA_DEBUG_LOG("frame_len: %d, block_len: %d, outbytes: %d, eaten: %d\n",
1174                 pwd->frame_len, pwd->block_len,
1175                 (int)((int8_t *)samples - (int8_t *)data), pwd->ahi.block_align);
1176         *data_size = (int8_t *)samples - (int8_t *)data;
1177         return pwd->ahi.block_align;
1178 fail:
1179         /* reset the bit reservoir on errors */
1180         pwd->last_superframe_len = 0;
1181         return ret;
1182 }
1183
1184 static void wmadec_close(struct filter_node *fn)
1185 {
1186         struct private_wmadec_data *pwd = fn->private_data;
1187
1188         if (!pwd)
1189                 return;
1190         wmadec_cleanup(pwd);
1191         free(fn->private_data);
1192         fn->private_data = NULL;
1193 }
1194
1195 static int wmadec_execute(struct btr_node *btrn, const char *cmd, char **result)
1196 {
1197         struct filter_node *fn = btr_context(btrn);
1198         struct private_wmadec_data *pwd = fn->private_data;
1199
1200         return decoder_execute(cmd, pwd->ahi.sample_rate, pwd->ahi.channels,
1201                 result);
1202 }
1203
1204 #define WMA_OUTPUT_BUFFER_SIZE (128 * 1024)
1205
1206 static int wmadec_post_select(__a_unused struct sched *s, void *context)
1207 {
1208         struct filter_node *fn = context;
1209         int ret, converted, out_size;
1210         struct private_wmadec_data *pwd = fn->private_data;
1211         struct btr_node *btrn = fn->btrn;
1212         size_t len;
1213         char *in, *out;
1214
1215 next_buffer:
1216         converted = 0;
1217         ret = btr_node_status(btrn, fn->min_iqs, BTR_NT_INTERNAL);
1218         if (ret < 0)
1219                 goto err;
1220         if (ret == 0)
1221                 return 0;
1222         btr_merge(btrn, fn->min_iqs);
1223         len = btr_next_buffer(btrn, (char **)&in);
1224         ret = -E_WMADEC_EOF;
1225         if (len < fn->min_iqs)
1226                 goto err;
1227         if (!pwd) {
1228                 ret = wma_decode_init(in, len, &pwd);
1229                 if (ret < 0)
1230                         goto err;
1231                 if (ret == 0) {
1232                         fn->min_iqs += 4096;
1233                         goto next_buffer;
1234                 }
1235                 fn->min_iqs = 2 * (WMA_FRAME_SKIP + pwd->ahi.block_align);
1236                 fn->private_data = pwd;
1237                 converted = pwd->ahi.header_len;
1238                 goto success;
1239         }
1240         fn->min_iqs = WMA_FRAME_SKIP + pwd->ahi.block_align;
1241         if (fn->min_iqs > len)
1242                 goto success;
1243         out_size = WMA_OUTPUT_BUFFER_SIZE;
1244         out = para_malloc(out_size);
1245         ret = wma_decode_superframe(pwd, out, &out_size,
1246                 (uint8_t *)in + WMA_FRAME_SKIP, len - WMA_FRAME_SKIP);
1247         if (ret < 0) {
1248                 free(out);
1249                 goto err;
1250         }
1251         out = para_realloc(out, out_size);
1252         if (out_size > 0)
1253                 btr_add_output(out, out_size, btrn);
1254         converted += ret + WMA_FRAME_SKIP;
1255 success:
1256         btr_consume(btrn, converted);
1257         return 0;
1258 err:
1259         assert(ret < 0);
1260         btr_remove_node(&fn->btrn);
1261         return ret;
1262 }
1263
1264 static void wmadec_open(struct filter_node *fn)
1265 {
1266         fn->private_data = NULL;
1267         fn->min_iqs = 4096;
1268 }
1269
1270 /**
1271  * The init function of the wma decoder.
1272  *
1273  * \param f Its fields are filled in by the function.
1274  */
1275 void wmadec_filter_init(struct filter *f)
1276 {
1277         f->open = wmadec_open;
1278         f->close = wmadec_close;
1279         f->execute = wmadec_execute;
1280         f->pre_select = generic_filter_pre_select;
1281         f->post_select = wmadec_post_select;
1282 }