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 <math.h>
  21 #include <regex.h>
  22 #include <sys/select.h>
  23
  24 #include "para.h"
  25 #include "error.h"
  26 #include "list.h"
  27 #include "ggo.h"
  28 #include "string.h"
  29 #include "sched.h"
  30 #include "buffer_tree.h"
  31 #include "filter.h"
  32 #include "portable_io.h"
  33 #include "bitstream.h"
  34 #include "imdct.h"
  35 #include "wma.h"
  36 #include "wmadata.h"
  37
  38
  39 /* size of blocks */
  40 #define BLOCK_MIN_BITS 7
  41 #define BLOCK_MAX_BITS 11
  42 #define BLOCK_MAX_SIZE (1 << BLOCK_MAX_BITS)
  43
  44 #define BLOCK_NB_SIZES (BLOCK_MAX_BITS - BLOCK_MIN_BITS + 1)
  45
  46 /* XXX: find exact max size */
  47 #define HIGH_BAND_MAX_SIZE 16
  48
  49 /* XXX: is it a suitable value ? */
  50 #define MAX_CODED_SUPERFRAME_SIZE 16384
  51
  52 #define MAX_CHANNELS 2
  53
  54 #define NOISE_TAB_SIZE 8192
  55
  56 #define LSP_POW_BITS 7
  57
  58 struct private_wmadec_data {
  59         /** Information contained in the audio file header. */
  60         struct asf_header_info ahi;
  61         struct getbit_context gb;
  62         /** Whether perceptual noise is added. */
  63         int use_noise_coding;
  64         /** Depends on number of the bits per second and the frame length. */
  65         int byte_offset_bits;
  66         /** Only used if ahi->use_exp_vlc is true. */
  67         struct vlc exp_vlc;
  68         uint16_t exponent_bands[BLOCK_NB_SIZES][25];
  69         /** The index of the first coef in high band. */
  70         int high_band_start[BLOCK_NB_SIZES];
  71         /** Maximal number of coded coefficients. */
  72         int coefs_end[BLOCK_NB_SIZES];
  73         int exponent_high_sizes[BLOCK_NB_SIZES];
  74         int exponent_high_bands[BLOCK_NB_SIZES][HIGH_BAND_MAX_SIZE];
  75         struct vlc hgain_vlc;
  76
  77         /* coded values in high bands */
  78         int high_band_coded[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
  79         int high_band_values[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
  80
  81         /* there are two possible tables for spectral coefficients */
  82         struct vlc coef_vlc[2];
  83         uint16_t *run_table[2];
  84         uint16_t *level_table[2];
  85         const struct coef_vlc_table *coef_vlcs[2];
  86         /** Frame length in samples. */
  87         int frame_len;
  88         /** log2 of frame_len. */
  89         int frame_len_bits;
  90         /** Number of block sizes, one if !ahi->use_variable_block_len. */
  91         int nb_block_sizes;
  92         /* Whether to update block lengths from getbit context. */
  93         bool reset_block_lengths;
  94         /** log2 of current block length. */
  95         int block_len_bits;
  96         /** log2 of next block length. */
  97         int next_block_len_bits;
  98         /** log2 of previous block length. */
  99         int prev_block_len_bits;
 100         /** Block length in samples. */
 101         int block_len;
 102         /** Current position in frame. */
 103         int block_pos;
 104         /** True if mid/side stereo mode. */
 105         uint8_t ms_stereo;
 106         /** True if channel is coded. */
 107         uint8_t channel_coded[MAX_CHANNELS];
 108         /** log2 ratio frame/exp. length. */
 109         int exponents_bsize[MAX_CHANNELS];
 110
 111         float exponents[MAX_CHANNELS][BLOCK_MAX_SIZE];
 112         float max_exponent[MAX_CHANNELS];
 113         int16_t coefs1[MAX_CHANNELS][BLOCK_MAX_SIZE];
 114         float coefs[MAX_CHANNELS][BLOCK_MAX_SIZE];
 115         float output[BLOCK_MAX_SIZE * 2];
 116         struct mdct_context *mdct_ctx[BLOCK_NB_SIZES];
 117         float *windows[BLOCK_NB_SIZES];
 118         /** Output buffer for one frame and the last for IMDCT windowing. */
 119         float frame_out[MAX_CHANNELS][BLOCK_MAX_SIZE * 2];
 120         /** Last frame info. */
 121         uint8_t last_superframe[MAX_CODED_SUPERFRAME_SIZE + 4]; /* padding added */
 122         int last_bitoffset;
 123         int last_superframe_len;
 124         float noise_table[NOISE_TAB_SIZE];
 125         int noise_index;
 126         float noise_mult;       /* XXX: suppress that and integrate it in the noise array */
 127         /* lsp_to_curve tables */
 128         float lsp_cos_table[BLOCK_MAX_SIZE];
 129         float lsp_pow_e_table[256];
 130         float lsp_pow_m_table1[(1 << LSP_POW_BITS)];
 131         float lsp_pow_m_table2[(1 << LSP_POW_BITS)];
 132 };
 133
 134 #define EXPVLCBITS 8
 135 #define HGAINVLCBITS 9
 136 #define VLCBITS 9
 137
 138 /** \cond sine_winows */
 139
 140 #define SINE_WINDOW(x) static float sine_ ## x[x] __a_aligned(16)
 141
 142 SINE_WINDOW(128);
 143 SINE_WINDOW(256);
 144 SINE_WINDOW(512);
 145 SINE_WINDOW(1024);
 146 SINE_WINDOW(2048);
 147 SINE_WINDOW(4096);
 148
 149 static float *sine_windows[6] = {
 150         sine_128, sine_256, sine_512, sine_1024, sine_2048, sine_4096
 151 };
 152 /** \endcond sine_windows */
 153
 154 /* Generate a sine window. */
 155 static void sine_window_init(float *window, int n)
 156 {
 157         int i;
 158
 159         for (i = 0; i < n; i++)
 160                 window[i] = sinf((i + 0.5) * (M_PI / (2.0 * n)));
 161 }
 162
 163 static void wmadec_cleanup(struct private_wmadec_data *pwd)
 164 {
 165         int i;
 166
 167         for (i = 0; i < pwd->nb_block_sizes; i++)
 168                 imdct_end(pwd->mdct_ctx[i]);
 169         if (pwd->ahi.use_exp_vlc)
 170                 free_vlc(&pwd->exp_vlc);
 171         if (pwd->use_noise_coding)
 172                 free_vlc(&pwd->hgain_vlc);
 173         for (i = 0; i < 2; i++) {
 174                 free_vlc(&pwd->coef_vlc[i]);
 175                 free(pwd->run_table[i]);
 176                 free(pwd->level_table[i]);
 177         }
 178 }
 179
 180 static void init_coef_vlc(struct vlc *vlc, uint16_t **prun_table,
 181                 uint16_t **plevel_table, const struct coef_vlc_table *vlc_table)
 182 {
 183         int n = vlc_table->n;
 184         const uint8_t *table_bits = vlc_table->huffbits;
 185         const uint32_t *table_codes = vlc_table->huffcodes;
 186         const uint16_t *levels_table = vlc_table->levels;
 187         uint16_t *run_table, *level_table;
 188         int i, l, j, k, level;
 189
 190         init_vlc(vlc, VLCBITS, n, table_bits, table_codes, 4);
 191
 192         run_table = para_malloc(n * sizeof(uint16_t));
 193         level_table = para_malloc(n * sizeof(uint16_t));
 194         i = 2;
 195         level = 1;
 196         k = 0;
 197         while (i < n) {
 198                 l = levels_table[k++];
 199                 for (j = 0; j < l; j++) {
 200                         run_table[i] = j;
 201                         level_table[i] = level;
 202                         i++;
 203                 }
 204                 level++;
 205         }
 206         *prun_table = run_table;
 207         *plevel_table = level_table;
 208 }
 209
 210 /* compute the scale factor band sizes for each MDCT block size */
 211 static void compute_scale_factor_band_sizes(struct private_wmadec_data *pwd,
 212         float high_freq)
 213 {
 214         struct asf_header_info *ahi = &pwd->ahi;
 215         int a, b, pos, lpos, k, block_len, i, j, n;
 216         const uint8_t *table;
 217
 218         for (k = 0; k < pwd->nb_block_sizes; k++) {
 219                 int exponent_size;
 220
 221                 block_len = pwd->frame_len >> k;
 222                 table = NULL;
 223                 a = pwd->frame_len_bits - BLOCK_MIN_BITS - k;
 224                 if (a < 3) {
 225                         if (ahi->sample_rate >= 44100)
 226                                 table = exponent_band_44100[a];
 227                         else if (ahi->sample_rate >= 32000)
 228                                 table = exponent_band_32000[a];
 229                         else if (ahi->sample_rate >= 22050)
 230                                 table = exponent_band_22050[a];
 231                 }
 232                 if (table) {
 233                         n = *table++;
 234                         for (i = 0; i < n; i++)
 235                                 pwd->exponent_bands[k][i] = table[i];
 236                         exponent_size = n;
 237                 } else {
 238                         j = 0;
 239                         lpos = 0;
 240                         for (i = 0; i < 25; i++) {
 241                                 a = wma_critical_freqs[i];
 242                                 b = ahi->sample_rate;
 243                                 pos = ((block_len * 2 * a) + (b << 1)) / (4 * b);
 244                                 pos <<= 2;
 245                                 if (pos > block_len)
 246                                         pos = block_len;
 247                                 if (pos > lpos)
 248                                         pwd->exponent_bands[k][j++] = pos - lpos;
 249                                 if (pos >= block_len)
 250                                         break;
 251                                 lpos = pos;
 252                         }
 253                         exponent_size = j;
 254                 }
 255
 256                 /* max number of coefs */
 257                 pwd->coefs_end[k] = (pwd->frame_len - ((pwd->frame_len * 9) / 100)) >> k;
 258                 /* high freq computation */
 259                 pwd->high_band_start[k] = (int) ((block_len * 2 * high_freq)
 260                         / ahi->sample_rate + 0.5);
 261                 n = exponent_size;
 262                 j = 0;
 263                 pos = 0;
 264                 for (i = 0; i < n; i++) {
 265                         int start, end;
 266                         start = pos;
 267                         pos += pwd->exponent_bands[k][i];
 268                         end = pos;
 269                         if (start < pwd->high_band_start[k])
 270                                 start = pwd->high_band_start[k];
 271                         if (end > pwd->coefs_end[k])
 272                                 end = pwd->coefs_end[k];
 273                         if (end > start)
 274                                 pwd->exponent_high_bands[k][j++] = end - start;
 275                 }
 276                 pwd->exponent_high_sizes[k] = j;
 277         }
 278 }
 279
 280 static int wma_init(struct private_wmadec_data *pwd)
 281 {
 282         int i;
 283         float bps1, high_freq;
 284         volatile float bps;
 285         int sample_rate1;
 286         int coef_vlc_table;
 287         struct asf_header_info *ahi = &pwd->ahi;
 288         int flags2 = ahi->flags2;
 289
 290         if (ahi->sample_rate <= 0 || ahi->sample_rate > 50000
 291                 || ahi->channels <= 0 || ahi->channels > 8
 292                 || ahi->bit_rate <= 0)
 293                 return -E_WMA_BAD_PARAMS;
 294
 295         /* compute MDCT block size */
 296         if (ahi->sample_rate <= 16000)
 297                 pwd->frame_len_bits = 9;
 298         else if (ahi->sample_rate <= 22050)
 299                 pwd->frame_len_bits = 10;
 300         else
 301                 pwd->frame_len_bits = 11;
 302         pwd->frame_len = 1 << pwd->frame_len_bits;
 303         if (pwd->ahi.use_variable_block_len) {
 304                 int nb_max, nb;
 305                 nb = ((flags2 >> 3) & 3) + 1;
 306                 if ((ahi->bit_rate / ahi->channels) >= 32000)
 307                         nb += 2;
 308                 nb_max = pwd->frame_len_bits - BLOCK_MIN_BITS;
 309                 if (nb > nb_max)
 310                         nb = nb_max;
 311                 pwd->nb_block_sizes = nb + 1;
 312         } else
 313                 pwd->nb_block_sizes = 1;
 314
 315         /* init rate dependent parameters */
 316         pwd->use_noise_coding = 1;
 317         high_freq = ahi->sample_rate * 0.5;
 318
 319         /* wma2 rates are normalized */
 320         sample_rate1 = ahi->sample_rate;
 321         if (sample_rate1 >= 44100)
 322                 sample_rate1 = 44100;
 323         else if (sample_rate1 >= 22050)
 324                 sample_rate1 = 22050;
 325         else if (sample_rate1 >= 16000)
 326                 sample_rate1 = 16000;
 327         else if (sample_rate1 >= 11025)
 328                 sample_rate1 = 11025;
 329         else if (sample_rate1 >= 8000)
 330                 sample_rate1 = 8000;
 331
 332         bps = (float) ahi->bit_rate / (float) (ahi->channels * ahi->sample_rate);
 333         pwd->byte_offset_bits = wma_log2((int) (bps * pwd->frame_len / 8.0 + 0.5)) + 2;
 334         /*
 335          * Compute high frequency value and choose if noise coding should be
 336          * activated.
 337          */
 338         bps1 = bps;
 339         if (ahi->channels == 2)
 340                 bps1 = bps * 1.6;
 341         if (sample_rate1 == 44100) {
 342                 if (bps1 >= 0.61)
 343                         pwd->use_noise_coding = 0;
 344                 else
 345                         high_freq = high_freq * 0.4;
 346         } else if (sample_rate1 == 22050) {
 347                 if (bps1 >= 1.16)
 348                         pwd->use_noise_coding = 0;
 349                 else if (bps1 >= 0.72)
 350                         high_freq = high_freq * 0.7;
 351                 else
 352                         high_freq = high_freq * 0.6;
 353         } else if (sample_rate1 == 16000) {
 354                 if (bps > 0.5)
 355                         high_freq = high_freq * 0.5;
 356                 else
 357                         high_freq = high_freq * 0.3;
 358         } else if (sample_rate1 == 11025)
 359                 high_freq = high_freq * 0.7;
 360         else if (sample_rate1 == 8000) {
 361                 if (bps <= 0.625)
 362                         high_freq = high_freq * 0.5;
 363                 else if (bps > 0.75)
 364                         pwd->use_noise_coding = 0;
 365                 else
 366                         high_freq = high_freq * 0.65;
 367         } else {
 368                 if (bps >= 0.8)
 369                         high_freq = high_freq * 0.75;
 370                 else if (bps >= 0.6)
 371                         high_freq = high_freq * 0.6;
 372                 else
 373                         high_freq = high_freq * 0.5;
 374         }
 375         PARA_INFO_LOG("channels=%u sample_rate=%u "
 376                 "bitrate=%u block_align=%d\n",
 377                 ahi->channels, ahi->sample_rate,
 378                 ahi->bit_rate, ahi->block_align);
 379         PARA_INFO_LOG("frame_len=%d, bps=%f bps1=%f "
 380                 "high_freq=%f bitoffset=%d\n",
 381                 pwd->frame_len, bps, bps1,
 382                 high_freq, pwd->byte_offset_bits);
 383         PARA_INFO_LOG("use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n",
 384                 pwd->use_noise_coding, pwd->ahi.use_exp_vlc, pwd->nb_block_sizes);
 385
 386         compute_scale_factor_band_sizes(pwd, high_freq);
 387         /* init MDCT windows : simple sinus window */
 388         for (i = 0; i < pwd->nb_block_sizes; i++) {
 389                 int n;
 390                 n = 1 << (pwd->frame_len_bits - i);
 391                 sine_window_init(sine_windows[pwd->frame_len_bits - i - 7], n);
 392                 pwd->windows[i] = sine_windows[pwd->frame_len_bits - i - 7];
 393         }
 394
 395         pwd->reset_block_lengths = true;
 396
 397         if (pwd->use_noise_coding) {
 398                 /* init the noise generator */
 399                 if (pwd->ahi.use_exp_vlc)
 400                         pwd->noise_mult = 0.02;
 401                 else
 402                         pwd->noise_mult = 0.04;
 403
 404                 {
 405                         unsigned int seed;
 406                         float norm;
 407                         seed = 1;
 408                         norm = (1.0 / (float) (1LL << 31)) * sqrt(3) * pwd->noise_mult;
 409                         for (i = 0; i < NOISE_TAB_SIZE; i++) {
 410                                 seed = seed * 314159 + 1;
 411                                 pwd->noise_table[i] = (float) ((int) seed) * norm;
 412                         }
 413                 }
 414         }
 415
 416         /* choose the VLC tables for the coefficients */
 417         coef_vlc_table = 2;
 418         if (ahi->sample_rate >= 32000) {
 419                 if (bps1 < 0.72)
 420                         coef_vlc_table = 0;
 421                 else if (bps1 < 1.16)
 422                         coef_vlc_table = 1;
 423         }
 424         pwd->coef_vlcs[0] = &coef_vlcs[coef_vlc_table * 2];
 425         pwd->coef_vlcs[1] = &coef_vlcs[coef_vlc_table * 2 + 1];
 426         init_coef_vlc(&pwd->coef_vlc[0], &pwd->run_table[0], &pwd->level_table[0],
 427                 pwd->coef_vlcs[0]);
 428         init_coef_vlc(&pwd->coef_vlc[1], &pwd->run_table[1], &pwd->level_table[1],
 429                 pwd->coef_vlcs[1]);
 430         return 0;
 431 }
 432
 433 static void wma_lsp_to_curve_init(struct private_wmadec_data *pwd)
 434 {
 435         float wdel, a, b;
 436         int i, e, m;
 437
 438         wdel = M_PI / pwd->frame_len;
 439         for (i = 0; i < pwd->frame_len; i++)
 440                 pwd->lsp_cos_table[i] = 2.0f * cos(wdel * i);
 441
 442         /* tables for x^-0.25 computation */
 443         for (i = 0; i < 256; i++) {
 444                 e = i - 126;
 445                 pwd->lsp_pow_e_table[i] = pow(2.0, e * -0.25);
 446         }
 447
 448         /* These two tables are needed to avoid two operations in pow_m1_4. */
 449         b = 1.0;
 450         for (i = (1 << LSP_POW_BITS) - 1; i >= 0; i--) {
 451                 m = (1 << LSP_POW_BITS) + i;
 452                 a = (float) m *(0.5 / (1 << LSP_POW_BITS));
 453                 a = pow(a, -0.25);
 454                 pwd->lsp_pow_m_table1[i] = 2 * a - b;
 455                 pwd->lsp_pow_m_table2[i] = b - a;
 456                 b = a;
 457         }
 458 }
 459
 460 static int wma_decode_init(char *initial_buf, int len, struct private_wmadec_data **result)
 461 {
 462         struct private_wmadec_data *pwd;
 463         int ret, i;
 464
 465         PARA_NOTICE_LOG("initial buf: %d bytes\n", len);
 466         pwd = para_calloc(sizeof(*pwd));
 467         ret = read_asf_header(initial_buf, len, &pwd->ahi);
 468         if (ret <= 0) {
 469                 free(pwd);
 470                 return ret;
 471         }
 472
 473         ret = wma_init(pwd);
 474         if (ret < 0)
 475                 return ret;
 476         /* init MDCT */
 477         for (i = 0; i < pwd->nb_block_sizes; i++) {
 478                 ret = imdct_init(pwd->frame_len_bits - i + 1, &pwd->mdct_ctx[i]);
 479                 if (ret < 0)
 480                         return ret;
 481         }
 482         if (pwd->use_noise_coding) {
 483                 PARA_INFO_LOG("using noise coding\n");
 484                 init_vlc(&pwd->hgain_vlc, HGAINVLCBITS,
 485                         sizeof(wma_hgain_huffbits), wma_hgain_huffbits,
 486                         wma_hgain_huffcodes, 2);
 487         }
 488
 489         if (pwd->ahi.use_exp_vlc) {
 490                 PARA_INFO_LOG("using exp_vlc\n");
 491                 init_vlc(&pwd->exp_vlc, EXPVLCBITS, sizeof(wma_scale_huffbits),
 492                         wma_scale_huffbits, wma_scale_huffcodes, 4);
 493         } else {
 494                 PARA_INFO_LOG("using curve\n");
 495                 wma_lsp_to_curve_init(pwd);
 496         }
 497         *result = pwd;
 498         return pwd->ahi.header_len;
 499 }
 500
 501 /**
 502  * compute x^-0.25 with an exponent and mantissa table. We use linear
 503  * interpolation to reduce the mantissa table size at a small speed
 504  * expense (linear interpolation approximately doubles the number of
 505  * bits of precision).
 506  */
 507 static inline float pow_m1_4(struct private_wmadec_data *pwd, float x)
 508 {
 509         union {
 510                 float f;
 511                 unsigned int v;
 512         } u, t;
 513         unsigned int e, m;
 514         float a, b;
 515
 516         u.f = x;
 517         e = u.v >> 23;
 518         m = (u.v >> (23 - LSP_POW_BITS)) & ((1 << LSP_POW_BITS) - 1);
 519         /* build interpolation scale: 1 <= t < 2. */
 520         t.v = ((u.v << LSP_POW_BITS) & ((1 << 23) - 1)) | (127 << 23);
 521         a = pwd->lsp_pow_m_table1[m];
 522         b = pwd->lsp_pow_m_table2[m];
 523         return pwd->lsp_pow_e_table[e] * (a + b * t.f);
 524 }
 525
 526 static void wma_lsp_to_curve(struct private_wmadec_data *pwd,
 527                 float *out, float *val_max_ptr, int n, float *lsp)
 528 {
 529         int i, j;
 530         float p, q, w, v, val_max;
 531
 532         val_max = 0;
 533         for (i = 0; i < n; i++) {
 534                 p = 0.5f;
 535                 q = 0.5f;
 536                 w = pwd->lsp_cos_table[i];
 537                 for (j = 1; j < NB_LSP_COEFS; j += 2) {
 538                         q *= w - lsp[j - 1];
 539                         p *= w - lsp[j];
 540                 }
 541                 p *= p * (2.0f - w);
 542                 q *= q * (2.0f + w);
 543                 v = p + q;
 544                 v = pow_m1_4(pwd, v);
 545                 if (v > val_max)
 546                         val_max = v;
 547                 out[i] = v;
 548         }
 549         *val_max_ptr = val_max;
 550 }
 551
 552 /* Decode exponents coded with LSP coefficients (same idea as Vorbis). */
 553 static void decode_exp_lsp(struct private_wmadec_data *pwd, int ch)
 554 {
 555         float lsp_coefs[NB_LSP_COEFS];
 556         int val, i;
 557
 558         for (i = 0; i < NB_LSP_COEFS; i++) {
 559                 if (i == 0 || i >= 8)
 560                         val = get_bits(&pwd->gb, 3);
 561                 else
 562                         val = get_bits(&pwd->gb, 4);
 563                 lsp_coefs[i] = wma_lsp_codebook[i][val];
 564         }
 565
 566         wma_lsp_to_curve(pwd, pwd->exponents[ch], &pwd->max_exponent[ch],
 567                 pwd->block_len, lsp_coefs);
 568 }
 569
 570 /* Decode exponents coded with VLC codes. */
 571 static int decode_exp_vlc(struct private_wmadec_data *pwd, int ch)
 572 {
 573         int last_exp, n, code;
 574         const uint16_t *ptr, *band_ptr;
 575         float v, *q, max_scale, *q_end;
 576
 577         band_ptr = pwd->exponent_bands[pwd->frame_len_bits - pwd->block_len_bits];
 578         ptr = band_ptr;
 579         q = pwd->exponents[ch];
 580         q_end = q + pwd->block_len;
 581         max_scale = 0;
 582         last_exp = 36;
 583
 584         while (q < q_end) {
 585                 code = get_vlc(&pwd->gb, pwd->exp_vlc.table, EXPVLCBITS);
 586                 if (code < 0)
 587                         return code;
 588                 /* NOTE: this offset is the same as MPEG4 AAC ! */
 589                 last_exp += code - 60;
 590                 /* XXX: use a table */
 591                 v = pow(10, last_exp * (1.0 / 16.0));
 592                 if (v > max_scale)
 593                         max_scale = v;
 594                 n = *ptr++;
 595                 do {
 596                         *q++ = v;
 597                 } while (--n);
 598         }
 599         pwd->max_exponent[ch] = max_scale;
 600         return 0;
 601 }
 602
 603 /* compute src0 * src1 + src2 */
 604 static inline void vector_mult_add(float *dst, const float *src0, const float *src1,
 605                 const float *src2, int len)
 606 {
 607         int i;
 608
 609         for (i = 0; i < len; i++)
 610                 dst[i] = src0[i] * src1[i] + src2[i];
 611 }
 612
 613 static inline void vector_mult_reverse(float *dst, const float *src0,
 614                 const float *src1, int len)
 615 {
 616         int i;
 617
 618         src1 += len - 1;
 619         for (i = 0; i < len; i++)
 620                 dst[i] = src0[i] * src1[-i];
 621 }
 622
 623 /**
 624  * Apply MDCT window and add into output.
 625  *
 626  * We ensure that when the windows overlap their squared sum
 627  * is always 1 (MDCT reconstruction rule).
 628  */
 629 static void wma_window(struct private_wmadec_data *pwd, float *out)
 630 {
 631         float *in = pwd->output;
 632         int block_len, bsize, n;
 633
 634         /* left part */
 635         if (pwd->block_len_bits <= pwd->prev_block_len_bits) {
 636                 block_len = pwd->block_len;
 637                 bsize = pwd->frame_len_bits - pwd->block_len_bits;
 638                 vector_mult_add(out, in, pwd->windows[bsize], out, block_len);
 639         } else {
 640                 block_len = 1 << pwd->prev_block_len_bits;
 641                 n = (pwd->block_len - block_len) / 2;
 642                 bsize = pwd->frame_len_bits - pwd->prev_block_len_bits;
 643                 vector_mult_add(out + n, in + n, pwd->windows[bsize], out + n,
 644                         block_len);
 645                 memcpy(out + n + block_len, in + n + block_len,
 646                         n * sizeof(float));
 647         }
 648         out += pwd->block_len;
 649         in += pwd->block_len;
 650         /* right part */
 651         if (pwd->block_len_bits <= pwd->next_block_len_bits) {
 652                 block_len = pwd->block_len;
 653                 bsize = pwd->frame_len_bits - pwd->block_len_bits;
 654                 vector_mult_reverse(out, in, pwd->windows[bsize], block_len);
 655         } else {
 656                 block_len = 1 << pwd->next_block_len_bits;
 657                 n = (pwd->block_len - block_len) / 2;
 658                 bsize = pwd->frame_len_bits - pwd->next_block_len_bits;
 659                 memcpy(out, in, n * sizeof(float));
 660                 vector_mult_reverse(out + n, in + n, pwd->windows[bsize],
 661                         block_len);
 662                 memset(out + n + block_len, 0, n * sizeof(float));
 663         }
 664 }
 665
 666 static int wma_total_gain_to_bits(int total_gain)
 667 {
 668         if (total_gain < 15)
 669                 return 13;
 670         else if (total_gain < 32)
 671                 return 12;
 672         else if (total_gain < 40)
 673                 return 11;
 674         else if (total_gain < 45)
 675                 return 10;
 676         else
 677                 return 9;
 678 }
 679
 680 static int compute_high_band_values(struct private_wmadec_data *pwd,
 681                 int bsize, int nb_coefs[MAX_CHANNELS])
 682 {
 683         int ch;
 684
 685         if (!pwd->use_noise_coding)
 686                 return 0;
 687         for (ch = 0; ch < pwd->ahi.channels; ch++) {
 688                 int i, m, a;
 689                 if (!pwd->channel_coded[ch])
 690                         continue;
 691                 m = pwd->exponent_high_sizes[bsize];
 692                 for (i = 0; i < m; i++) {
 693                         a = get_bit(&pwd->gb);
 694                         pwd->high_band_coded[ch][i] = a;
 695                         if (!a)
 696                                 continue;
 697                         nb_coefs[ch] -= pwd->exponent_high_bands[bsize][i];
 698                 }
 699         }
 700         for (ch = 0; ch < pwd->ahi.channels; ch++) {
 701                 int i, n, val;
 702                 if (!pwd->channel_coded[ch])
 703                         continue;
 704                 n = pwd->exponent_high_sizes[bsize];
 705                 val = (int)0x80000000;
 706                 for (i = 0; i < n; i++) {
 707                         if (!pwd->high_band_coded[ch][i])
 708                                 continue;
 709                         if (val == (int)0x80000000)
 710                                 val = get_bits(&pwd->gb, 7) - 19;
 711                         else {
 712                                 int code = get_vlc(&pwd->gb,
 713                                         pwd->hgain_vlc.table, HGAINVLCBITS);
 714                                 if (code < 0)
 715                                         return code;
 716                                 val += code - 18;
 717                         }
 718                         pwd->high_band_values[ch][i] = val;
 719                 }
 720         }
 721         return 1;
 722 }
 723
 724 static void compute_mdct_coefficients(struct private_wmadec_data *pwd,
 725                 int bsize, int total_gain, int nb_coefs[MAX_CHANNELS])
 726 {
 727         int ch;
 728         float mdct_norm = 1.0 / (pwd->block_len / 2);
 729
 730         for (ch = 0; ch < pwd->ahi.channels; ch++) {
 731                 int16_t *coefs1;
 732                 float *coefs, *exponents, mult, mult1, noise;
 733                 int i, j, n, n1, last_high_band, esize;
 734                 float exp_power[HIGH_BAND_MAX_SIZE];
 735
 736                 if (!pwd->channel_coded[ch])
 737                         continue;
 738                 coefs1 = pwd->coefs1[ch];
 739                 exponents = pwd->exponents[ch];
 740                 esize = pwd->exponents_bsize[ch];
 741                 mult = pow(10, total_gain * 0.05) / pwd->max_exponent[ch];
 742                 mult *= mdct_norm;
 743                 coefs = pwd->coefs[ch];
 744                 if (!pwd->use_noise_coding) {
 745                         /* XXX: optimize more */
 746                         n = nb_coefs[ch];
 747                         for (i = 0; i < n; i++)
 748                                 *coefs++ = coefs1[i] *
 749                                         exponents[i << bsize >> esize] * mult;
 750                         n = pwd->block_len - pwd->coefs_end[bsize];
 751                         for (i = 0; i < n; i++)
 752                                 *coefs++ = 0.0;
 753                         continue;
 754                 }
 755                 n1 = pwd->exponent_high_sizes[bsize];
 756                 /* compute power of high bands */
 757                 exponents = pwd->exponents[ch] +
 758                         (pwd->high_band_start[bsize] << bsize);
 759                 last_high_band = 0; /* avoid warning */
 760                 for (j = 0; j < n1; j++) {
 761                         n = pwd->exponent_high_bands[
 762                                 pwd->frame_len_bits - pwd->block_len_bits][j];
 763                         if (pwd->high_band_coded[ch][j]) {
 764                                 float e2, val;
 765                                 e2 = 0;
 766                                 for (i = 0; i < n; i++) {
 767                                         val = exponents[i << bsize >> esize];
 768                                         e2 += val * val;
 769                                 }
 770                                 exp_power[j] = e2 / n;
 771                                 last_high_band = j;
 772                         }
 773                         exponents += n << bsize;
 774                 }
 775                 /* main freqs and high freqs */
 776                 exponents = pwd->exponents[ch];
 777                 for (j = -1; j < n1; j++) {
 778                         if (j < 0)
 779                                 n = pwd->high_band_start[bsize];
 780                         else
 781                                 n = pwd->exponent_high_bands[pwd->frame_len_bits
 782                                         - pwd->block_len_bits][j];
 783                         if (j >= 0 && pwd->high_band_coded[ch][j]) {
 784                                 /* use noise with specified power */
 785                                 mult1 = sqrt(exp_power[j]
 786                                         / exp_power[last_high_band]);
 787                                 /* XXX: use a table */
 788                                 mult1 *= pow(10, pwd->high_band_values[ch][j] * 0.05);
 789                                 mult1 /= (pwd->max_exponent[ch] * pwd->noise_mult);
 790                                 mult1 *= mdct_norm;
 791                                 for (i = 0; i < n; i++) {
 792                                         noise = pwd->noise_table[pwd->noise_index];
 793                                         pwd->noise_index = (pwd->noise_index + 1)
 794                                                 & (NOISE_TAB_SIZE - 1);
 795                                         *coefs++ = noise * exponents[
 796                                                 i << bsize >> esize] * mult1;
 797                                 }
 798                                 exponents += n << bsize;
 799                         } else {
 800                                 /* coded values + small noise */
 801                                 for (i = 0; i < n; i++) {
 802                                         noise = pwd->noise_table[pwd->noise_index];
 803                                         pwd->noise_index = (pwd->noise_index + 1)
 804                                                 & (NOISE_TAB_SIZE - 1);
 805                                         *coefs++ = ((*coefs1++) + noise) *
 806                                                 exponents[i << bsize >> esize]
 807                                                 * mult;
 808                                 }
 809                                 exponents += n << bsize;
 810                         }
 811                 }
 812                 /* very high freqs: noise */
 813                 n = pwd->block_len - pwd->coefs_end[bsize];
 814                 mult1 = mult * exponents[(-(1 << bsize)) >> esize];
 815                 for (i = 0; i < n; i++) {
 816                         *coefs++ = pwd->noise_table[pwd->noise_index] * mult1;
 817                         pwd->noise_index = (pwd->noise_index + 1)
 818                                 & (NOISE_TAB_SIZE - 1);
 819                 }
 820         }
 821 }
 822
 823 /**
 824  * Returns 0 if OK, 1 if last block of frame, negative on uncorrectable
 825  * errors.
 826  */
 827 static int wma_decode_block(struct private_wmadec_data *pwd)
 828 {
 829         int ret, n, v, ch, code, bsize;
 830         int coef_nb_bits, total_gain;
 831         int nb_coefs[MAX_CHANNELS];
 832
 833         /* compute current block length */
 834         if (pwd->ahi.use_variable_block_len) {
 835                 n = wma_log2(pwd->nb_block_sizes - 1) + 1;
 836
 837                 if (pwd->reset_block_lengths) {
 838                         pwd->reset_block_lengths = false;
 839                         v = get_bits(&pwd->gb, n);
 840                         if (v >= pwd->nb_block_sizes)
 841                                 return -E_WMA_BLOCK_SIZE;
 842                         pwd->prev_block_len_bits = pwd->frame_len_bits - v;
 843                         v = get_bits(&pwd->gb, n);
 844                         if (v >= pwd->nb_block_sizes)
 845                                 return -E_WMA_BLOCK_SIZE;
 846                         pwd->block_len_bits = pwd->frame_len_bits - v;
 847                 } else {
 848                         /* update block lengths */
 849                         pwd->prev_block_len_bits = pwd->block_len_bits;
 850                         pwd->block_len_bits = pwd->next_block_len_bits;
 851                 }
 852                 v = get_bits(&pwd->gb, n);
 853                 if (v >= pwd->nb_block_sizes)
 854                         return -E_WMA_BLOCK_SIZE;
 855                 pwd->next_block_len_bits = pwd->frame_len_bits - v;
 856         } else {
 857                 /* fixed block len */
 858                 pwd->next_block_len_bits = pwd->frame_len_bits;
 859                 pwd->prev_block_len_bits = pwd->frame_len_bits;
 860                 pwd->block_len_bits = pwd->frame_len_bits;
 861         }
 862
 863         /* now check if the block length is coherent with the frame length */
 864         pwd->block_len = 1 << pwd->block_len_bits;
 865         if ((pwd->block_pos + pwd->block_len) > pwd->frame_len)
 866                 return -E_INCOHERENT_BLOCK_LEN;
 867
 868         if (pwd->ahi.channels == 2)
 869                 pwd->ms_stereo = get_bit(&pwd->gb);
 870         v = 0;
 871         for (ch = 0; ch < pwd->ahi.channels; ch++) {
 872                 int a = get_bit(&pwd->gb);
 873                 pwd->channel_coded[ch] = a;
 874                 v |= a;
 875         }
 876
 877         bsize = pwd->frame_len_bits - pwd->block_len_bits;
 878
 879         /* if no channel coded, no need to go further */
 880         /* XXX: fix potential framing problems */
 881         if (!v)
 882                 goto next;
 883
 884         /*
 885          * Read total gain and extract corresponding number of bits for coef
 886          * escape coding.
 887          */
 888         total_gain = 1;
 889         for (;;) {
 890                 int a = get_bits(&pwd->gb, 7);
 891                 total_gain += a;
 892                 if (a != 127)
 893                         break;
 894         }
 895
 896         coef_nb_bits = wma_total_gain_to_bits(total_gain);
 897
 898         /* compute number of coefficients */
 899         n = pwd->coefs_end[bsize];
 900         for (ch = 0; ch < pwd->ahi.channels; ch++)
 901                 nb_coefs[ch] = n;
 902
 903         ret = compute_high_band_values(pwd, bsize, nb_coefs);
 904         if (ret < 0)
 905                 return ret;
 906
 907         /* exponents can be reused in short blocks. */
 908         if ((pwd->block_len_bits == pwd->frame_len_bits) || get_bit(&pwd->gb)) {
 909                 for (ch = 0; ch < pwd->ahi.channels; ch++) {
 910                         if (pwd->channel_coded[ch]) {
 911                                 if (pwd->ahi.use_exp_vlc) {
 912                                         ret = decode_exp_vlc(pwd, ch);
 913                                         if (ret < 0)
 914                                                 return ret;
 915                                 } else
 916                                         decode_exp_lsp(pwd, ch);
 917                                 pwd->exponents_bsize[ch] = bsize;
 918                         }
 919                 }
 920         }
 921
 922         /* parse spectral coefficients : just RLE encoding */
 923         for (ch = 0; ch < pwd->ahi.channels; ch++) {
 924                 struct vlc *coef_vlc;
 925                 int level, run, tindex;
 926                 int16_t *ptr, *eptr;
 927                 const uint16_t *level_table, *run_table;
 928
 929                 if (!pwd->channel_coded[ch])
 930                         continue;
 931                 /*
 932                  * special VLC tables are used for ms stereo because there is
 933                  * potentially less energy there
 934                  */
 935                 tindex = (ch == 1 && pwd->ms_stereo);
 936                 coef_vlc = &pwd->coef_vlc[tindex];
 937                 run_table = pwd->run_table[tindex];
 938                 level_table = pwd->level_table[tindex];
 939                 /* XXX: optimize */
 940                 ptr = &pwd->coefs1[ch][0];
 941                 eptr = ptr + nb_coefs[ch];
 942                 memset(ptr, 0, pwd->block_len * sizeof(int16_t));
 943                 for (;;) {
 944                         code = get_vlc(&pwd->gb, coef_vlc->table, VLCBITS);
 945                         if (code < 0)
 946                                 return code;
 947                         if (code == 1) /* EOB */
 948                                 break;
 949                         if (code == 0) { /* escape */
 950                                 level = get_bits(&pwd->gb, coef_nb_bits);
 951                                 /* reading block_len_bits would be better */
 952                                 run = get_bits(&pwd->gb, pwd->frame_len_bits);
 953                         } else { /* normal code */
 954                                 run = run_table[code];
 955                                 level = level_table[code];
 956                         }
 957                         if (!get_bit(&pwd->gb))
 958                                 level = -level;
 959                         ptr += run;
 960                         if (ptr >= eptr) {
 961                                 PARA_ERROR_LOG("overflow in spectral RLE, ignoring\n");
 962                                 break;
 963                         }
 964                         *ptr++ = level;
 965                         if (ptr >= eptr) /* EOB can be omitted */
 966                                 break;
 967                 }
 968         }
 969         compute_mdct_coefficients(pwd, bsize, total_gain, nb_coefs);
 970         if (pwd->ms_stereo && pwd->channel_coded[1]) {
 971                 float a, b;
 972                 int i;
 973                 /*
 974                  * Nominal case for ms stereo: we do it before mdct.
 975                  *
 976                  * No need to optimize this case because it should almost never
 977                  * happen.
 978                  */
 979                 if (!pwd->channel_coded[0]) {
 980                         PARA_NOTICE_LOG("rare ms-stereo\n");
 981                         memset(pwd->coefs[0], 0, sizeof(float) * pwd->block_len);
 982                         pwd->channel_coded[0] = 1;
 983                 }
 984                 for (i = 0; i < pwd->block_len; i++) {
 985                         a = pwd->coefs[0][i];
 986                         b = pwd->coefs[1][i];
 987                         pwd->coefs[0][i] = a + b;
 988                         pwd->coefs[1][i] = a - b;
 989                 }
 990         }
 991 next:
 992         for (ch = 0; ch < pwd->ahi.channels; ch++) {
 993                 int n4, idx;
 994
 995                 n4 = pwd->block_len / 2;
 996                 if (pwd->channel_coded[ch])
 997                         imdct(pwd->mdct_ctx[bsize], pwd->output, pwd->coefs[ch]);
 998                 else if (!(pwd->ms_stereo && ch == 1))
 999                         memset(pwd->output, 0, sizeof(pwd->output));
1000
1001                 /* multiply by the window and add in the frame */
1002                 idx = (pwd->frame_len / 2) + pwd->block_pos - n4;
1003                 wma_window(pwd, &pwd->frame_out[ch][idx]);
1004         }
1005
1006         /* update block number */
1007         pwd->block_pos += pwd->block_len;
1008         if (pwd->block_pos >= pwd->frame_len)
1009                 return 1;
1010         else
1011                 return 0;
1012 }
1013
1014 /*
1015  * Clip a signed integer value into the -32768,32767 range.
1016  *
1017  * \param a The value to clip.
1018  *
1019  * \return The clipped value.
1020  */
1021 static inline int16_t av_clip_int16(int a)
1022 {
1023         if ((a + 32768) & ~65535)
1024                 return (a >> 31) ^ 32767;
1025         else
1026                 return a;
1027 }
1028
1029 /* Decode a frame of frame_len samples. */
1030 static int wma_decode_frame(struct private_wmadec_data *pwd, int16_t *samples)
1031 {
1032         int ret, i, ch;
1033         int16_t *ptr;
1034         float *iptr;
1035
1036         /* read each block */
1037         pwd->block_pos = 0;
1038         for (;;) {
1039                 ret = wma_decode_block(pwd);
1040                 if (ret < 0)
1041                         return ret;
1042                 if (ret)
1043                         break;
1044         }
1045
1046         /* convert frame to integer */
1047         for (ch = 0; ch < pwd->ahi.channels; ch++) {
1048                 ptr = samples + ch;
1049                 iptr = pwd->frame_out[ch];
1050
1051                 for (i = 0; i < pwd->frame_len; i++) {
1052                         *ptr = av_clip_int16(lrintf(*iptr++));
1053                         ptr += pwd->ahi.channels;
1054                 }
1055                 /* prepare for next block */
1056                 memmove(&pwd->frame_out[ch][0], &pwd->frame_out[ch][pwd->frame_len],
1057                         pwd->frame_len * sizeof(float));
1058         }
1059         return 0;
1060 }
1061
1062 static int wma_decode_superframe(struct private_wmadec_data *pwd, void *data,
1063                 int *data_size, const uint8_t *buf, int buf_size)
1064 {
1065         int ret;
1066         int16_t *samples;
1067
1068         if (buf_size == 0) {
1069                 pwd->last_superframe_len = 0;
1070                 *data_size = 0;
1071                 return 0;
1072         }
1073         if (buf_size < pwd->ahi.block_align) {
1074                 *data_size = 0;
1075                 return 0;
1076         }
1077         buf_size = pwd->ahi.block_align;
1078         samples = data;
1079         init_get_bits(&pwd->gb, buf, buf_size);
1080         if (pwd->ahi.use_bit_reservoir) {
1081                 int i, nb_frames, bit_offset, pos, len;
1082                 uint8_t *q;
1083
1084                 /* read super frame header */
1085                 skip_bits(&pwd->gb, 4); /* super frame index */
1086                 nb_frames = get_bits(&pwd->gb, 4) - 1;
1087                 // PARA_DEBUG_LOG("have %d frames\n", nb_frames);
1088                 ret = -E_WMA_OUTPUT_SPACE;
1089                 if ((nb_frames + 1) * pwd->ahi.channels * pwd->frame_len
1090                                 * sizeof(int16_t) > *data_size)
1091                         goto fail;
1092
1093                 bit_offset = get_bits(&pwd->gb, pwd->byte_offset_bits + 3);
1094
1095                 if (pwd->last_superframe_len > 0) {
1096                         /* add bit_offset bits to last frame */
1097                         ret = -E_WMA_BAD_SUPERFRAME;
1098                         if ((pwd->last_superframe_len + ((bit_offset + 7) >> 3)) >
1099                                         MAX_CODED_SUPERFRAME_SIZE)
1100                                 goto fail;
1101                         q = pwd->last_superframe + pwd->last_superframe_len;
1102                         len = bit_offset;
1103                         while (len > 7) {
1104                                 *q++ = get_bits(&pwd->gb, 8);
1105                                 len -= 8;
1106                         }
1107                         if (len > 0)
1108                                 *q++ = get_bits(&pwd->gb, len) << (8 - len);
1109
1110                         /* XXX: bit_offset bits into last frame */
1111                         init_get_bits(&pwd->gb, pwd->last_superframe,
1112                                 MAX_CODED_SUPERFRAME_SIZE);
1113                         /* skip unused bits */
1114                         if (pwd->last_bitoffset > 0)
1115                                 skip_bits(&pwd->gb, pwd->last_bitoffset);
1116                         /*
1117                          * This frame is stored in the last superframe and in
1118                          * the current one.
1119                          */
1120                         ret = wma_decode_frame(pwd, samples);
1121                         if (ret < 0)
1122                                 goto fail;
1123                         samples += pwd->ahi.channels * pwd->frame_len;
1124                 }
1125
1126                 /* read each frame starting from bit_offset */
1127                 pos = bit_offset + 4 + 4 + pwd->byte_offset_bits + 3;
1128                 init_get_bits(&pwd->gb, buf + (pos >> 3),
1129                         (MAX_CODED_SUPERFRAME_SIZE - (pos >> 3)));
1130                 len = pos & 7;
1131                 if (len > 0)
1132                         skip_bits(&pwd->gb, len);
1133
1134                 pwd->reset_block_lengths = true;
1135                 for (i = 0; i < nb_frames; i++) {
1136                         ret = wma_decode_frame(pwd, samples);
1137                         if (ret < 0)
1138                                 goto fail;
1139                         samples += pwd->ahi.channels * pwd->frame_len;
1140                 }
1141
1142                 /* we copy the end of the frame in the last frame buffer */
1143                 pos = get_bits_count(&pwd->gb) +
1144                         ((bit_offset + 4 + 4 + pwd->byte_offset_bits + 3) & ~7);
1145                 pwd->last_bitoffset = pos & 7;
1146                 pos >>= 3;
1147                 len = buf_size - pos;
1148                 ret = -E_WMA_BAD_SUPERFRAME;
1149                 if (len > MAX_CODED_SUPERFRAME_SIZE || len < 0)
1150                         goto fail;
1151                 pwd->last_superframe_len = len;
1152                 memcpy(pwd->last_superframe, buf + pos, len);
1153         } else {
1154                 PARA_DEBUG_LOG("not using bit reservoir\n");
1155                 ret = -E_WMA_OUTPUT_SPACE;
1156                 if (pwd->ahi.channels * pwd->frame_len * sizeof(int16_t) > *data_size)
1157                         goto fail;
1158                 /* single frame decode */
1159                 ret = wma_decode_frame(pwd, samples);
1160                 if (ret < 0)
1161                         goto fail;
1162                 samples += pwd->ahi.channels * pwd->frame_len;
1163         }
1164         PARA_DEBUG_LOG("frame_len: %d, block_len: %d, outbytes: %d, eaten: %d\n",
1165                 pwd->frame_len, pwd->block_len,
1166                 (int)((int8_t *)samples - (int8_t *)data), pwd->ahi.block_align);
1167         *data_size = (int8_t *)samples - (int8_t *)data;
1168         return pwd->ahi.block_align;
1169 fail:
1170         /* reset the bit reservoir on errors */
1171         pwd->last_superframe_len = 0;
1172         return ret;
1173 }
1174
1175 static void wmadec_close(struct filter_node *fn)
1176 {
1177         struct private_wmadec_data *pwd = fn->private_data;
1178
1179         if (!pwd)
1180                 return;
1181         wmadec_cleanup(pwd);
1182         free(fn->private_data);
1183         fn->private_data = NULL;
1184 }
1185
1186 static int wmadec_execute(struct btr_node *btrn, const char *cmd, char **result)
1187 {
1188         struct filter_node *fn = btr_context(btrn);
1189         struct private_wmadec_data *pwd = fn->private_data;
1190
1191         return decoder_execute(cmd, pwd->ahi.sample_rate, pwd->ahi.channels,
1192                 result);
1193 }
1194
1195 #define WMA_OUTPUT_BUFFER_SIZE (128 * 1024)
1196
1197 static int wmadec_post_select(__a_unused struct sched *s, void *context)
1198 {
1199         struct filter_node *fn = context;
1200         int ret, converted, out_size;
1201         struct private_wmadec_data *pwd = fn->private_data;
1202         struct btr_node *btrn = fn->btrn;
1203         size_t len;
1204         char *in, *out;
1205
1206 next_buffer:
1207         converted = 0;
1208         ret = btr_node_status(btrn, fn->min_iqs, BTR_NT_INTERNAL);
1209         if (ret < 0)
1210                 goto err;
1211         if (ret == 0)
1212                 return 0;
1213         btr_merge(btrn, fn->min_iqs);
1214         len = btr_next_buffer(btrn, &in);
1215         ret = -E_WMADEC_EOF;
1216         if (len < fn->min_iqs)
1217                 goto err;
1218         if (!pwd) {
1219                 ret = wma_decode_init(in, len, &pwd);
1220                 if (ret < 0)
1221                         goto err;
1222                 if (ret == 0) {
1223                         fn->min_iqs += 4096;
1224                         goto next_buffer;
1225                 }
1226                 fn->min_iqs = 2 * pwd->ahi.packet_size;
1227                 fn->private_data = pwd;
1228                 converted = pwd->ahi.header_len;
1229                 goto success;
1230         }
1231         fn->min_iqs = pwd->ahi.packet_size;
1232         if (fn->min_iqs > len)
1233                 goto success;
1234         out_size = WMA_OUTPUT_BUFFER_SIZE;
1235         out = para_malloc(out_size);
1236         ret = wma_decode_superframe(pwd, out, &out_size,
1237                 (uint8_t *)in + WMA_FRAME_SKIP, len - WMA_FRAME_SKIP);
1238         if (ret < 0) {
1239                 free(out);
1240                 goto err;
1241         }
1242         if (out_size > 0) {
1243                 out = para_realloc(out, out_size);
1244                 btr_add_output(out, out_size, btrn);
1245         } else
1246                 free(out);
1247         converted += pwd->ahi.packet_size;
1248 success:
1249         btr_consume(btrn, converted);
1250         return 0;
1251 err:
1252         assert(ret < 0);
1253         btr_remove_node(&fn->btrn);
1254         return ret;
1255 }
1256
1257 static void wmadec_open(struct filter_node *fn)
1258 {
1259         fn->private_data = NULL;
1260         fn->min_iqs = 4096;
1261 }
1262
1263 /**
1264  * The init function of the wma decoder.
1265  *
1266  * \param f Its fields are filled in by the function.
1267  */
1268 void wmadec_filter_init(struct filter *f)
1269 {
1270         f->open = wmadec_open;
1271         f->close = wmadec_close;
1272         f->execute = wmadec_execute;
1273         f->pre_select = generic_filter_pre_select;
1274         f->post_select = wmadec_post_select;
1275 }