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FFmpeg/libavcodec/vorbis_dec.c

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  1. /**

  2.  * @file libavcodec/vorbis_dec.c

  3.  * Vorbis I decoder

  4.  * @author Denes Balatoni  ( dbalatoni programozo hu )

  5.  *

  6.  * This file is part of FFmpeg.

  7.  *

  8.  * FFmpeg is free software; you can redistribute it and/or

  9.  * modify it under the terms of the GNU Lesser General Public

  10.  * License as published by the Free Software Foundation; either

  11.  * version 2.1 of the License, or (at your option) any later version.

  12.  *

  13.  * FFmpeg is distributed in the hope that it will be useful,

  14.  * but WITHOUT ANY WARRANTY; without even the implied warranty of

  15.  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

  16.  * Lesser General Public License for more details.

  17.  *

  18.  * You should have received a copy of the GNU Lesser General Public

  19.  * License along with FFmpeg; if not, write to the Free Software

  20.  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

  21.  */

  22. 

  23. #undef V_DEBUG

  24. //#define V_DEBUG

  25. //#define AV_DEBUG(...) av_log(NULL, AV_LOG_INFO, __VA_ARGS__)

  26. 

  27. #include <math.h>

  28. 

  29. #define ALT_BITSTREAM_READER_LE

  30. #include "avcodec.h"

  31. #include "get_bits.h"

  32. #include "dsputil.h"

  33. 

  34. #include "vorbis.h"

  35. #include "xiph.h"

  36. 

  37. #define V_NB_BITS 8

  38. #define V_NB_BITS2 11

  39. #define V_MAX_VLCS (1 << 16)

  40. #define V_MAX_PARTITIONS (1 << 20)

  41. 

  42. #ifndef V_DEBUG

  43. #define AV_DEBUG(...)

  44. #endif

  45. 

  46. #undef NDEBUG

  47. #include <assert.h>

  48. 

  49. typedef struct {

  50.     uint_fast8_t dimensions;

  51.     uint_fast8_t lookup_type;

  52.     uint_fast8_t maxdepth;

  53.     VLC vlc;

  54.     float *codevectors;

  55.     unsigned int nb_bits;

  56. } vorbis_codebook;

  57. 

  58. typedef union  vorbis_floor_u  vorbis_floor_data;

  59. typedef struct vorbis_floor0_s vorbis_floor0;

  60. typedef struct vorbis_floor1_s vorbis_floor1;

  61. struct vorbis_context_s;

  62. typedef

  63. uint_fast8_t (* vorbis_floor_decode_func)

  64.              (struct vorbis_context_s *, vorbis_floor_data *, float *);

  65. typedef struct {

  66.     uint_fast8_t floor_type;

  67.     vorbis_floor_decode_func decode;

  68.     union vorbis_floor_u {

  69.         struct vorbis_floor0_s {

  70.             uint_fast8_t  order;

  71.             uint_fast16_t rate;

  72.             uint_fast16_t bark_map_size;

  73.             int_fast32_t *map[2];

  74.             uint_fast32_t map_size[2];

  75.             uint_fast8_t  amplitude_bits;

  76.             uint_fast8_t  amplitude_offset;

  77.             uint_fast8_t  num_books;

  78.             uint_fast8_t *book_list;

  79.             float        *lsp;

  80.         } t0;

  81.         struct vorbis_floor1_s {

  82.             uint_fast8_t partitions;

  83.             uint_fast8_t maximum_class;

  84.             uint_fast8_t partition_class[32];

  85.             uint_fast8_t class_dimensions[16];

  86.             uint_fast8_t class_subclasses[16];

  87.             uint_fast8_t class_masterbook[16];

  88.             int_fast16_t subclass_books[16][8];

  89.             uint_fast8_t multiplier;

  90.             uint_fast16_t x_list_dim;

  91.             vorbis_floor1_entry *list;

  92.         } t1;

  93.     } data;

  94. } vorbis_floor;

  95. 

  96. typedef struct {

  97.     uint_fast16_t type;

  98.     uint_fast32_t begin;

  99.     uint_fast32_t end;

  100.     uint_fast32_t partition_size;

  101.     uint_fast8_t  classifications;

  102.     uint_fast8_t  classbook;

  103.     int_fast16_t  books[64][8];

  104.     uint_fast8_t  maxpass;

  105. } vorbis_residue;

  106. 

  107. typedef struct {

  108.     uint_fast8_t  submaps;

  109.     uint_fast16_t coupling_steps;

  110.     uint_fast8_t *magnitude;

  111.     uint_fast8_t *angle;

  112.     uint_fast8_t *mux;

  113.     uint_fast8_t  submap_floor[16];

  114.     uint_fast8_t  submap_residue[16];

  115. } vorbis_mapping;

  116. 

  117. typedef struct {

  118.     uint_fast8_t  blockflag;

  119.     uint_fast16_t windowtype;

  120.     uint_fast16_t transformtype;

  121.     uint_fast8_t  mapping;

  122. } vorbis_mode;

  123. 

  124. typedef struct vorbis_context_s {

  125.     AVCodecContext *avccontext;

  126.     GetBitContext gb;

  127.     DSPContext dsp;

  128. 

  129.     FFTContext mdct[2];

  130.     uint_fast8_t  first_frame;

  131.     uint_fast32_t version;

  132.     uint_fast8_t  audio_channels;

  133.     uint_fast32_t audio_samplerate;

  134.     uint_fast32_t bitrate_maximum;

  135.     uint_fast32_t bitrate_nominal;

  136.     uint_fast32_t bitrate_minimum;

  137.     uint_fast32_t blocksize[2];

  138.     const float  *win[2];

  139.     uint_fast16_t codebook_count;

  140.     vorbis_codebook *codebooks;

  141.     uint_fast8_t  floor_count;

  142.     vorbis_floor *floors;

  143.     uint_fast8_t  residue_count;

  144.     vorbis_residue *residues;

  145.     uint_fast8_t  mapping_count;

  146.     vorbis_mapping *mappings;

  147.     uint_fast8_t  mode_count;

  148.     vorbis_mode  *modes;

  149.     uint_fast8_t  mode_number; // mode number for the current packet

  150.     uint_fast8_t  previous_window;

  151.     float        *channel_residues;

  152.     float        *channel_floors;

  153.     float        *saved;

  154.     uint_fast32_t add_bias; // for float->int conversion

  155.     uint_fast32_t exp_bias;

  156. } vorbis_context;

  157. 

  158. /* Helper functions */

  159. 

  160. #define BARK(x) \

  161.     (13.1f * atan(0.00074f * (x)) + 2.24f * atan(1.85e-8f * (x) * (x)) + 1e-4f * (x))

  162. 

  163. static float vorbisfloat2float(uint_fast32_t val)

  164. {

  165.     double mant = val & 0x1fffff;

  166.     long exp    = (val & 0x7fe00000L) >> 21;

  167.     if (val & 0x80000000)

  168.         mant = -mant;

  169.     return ldexp(mant, exp - 20 - 768);

  170. }

  171. 

  172. 

  173. // Free all allocated memory -----------------------------------------

  174. 

  175. static void vorbis_free(vorbis_context *vc)

  176. {

  177.     int_fast16_t i;

  178. 

  179.     av_freep(&vc->channel_residues);

  180.     av_freep(&vc->channel_floors);

  181.     av_freep(&vc->saved);

  182. 

  183.     av_freep(&vc->residues);

  184.     av_freep(&vc->modes);

  185. 

  186.     ff_mdct_end(&vc->mdct[0]);

  187.     ff_mdct_end(&vc->mdct[1]);

  188. 

  189.     for (i = 0; i < vc->codebook_count; ++i) {

  190.         av_free(vc->codebooks[i].codevectors);

  191.         free_vlc(&vc->codebooks[i].vlc);

  192.     }

  193.     av_freep(&vc->codebooks);

  194. 

  195.     for (i = 0; i < vc->floor_count; ++i) {

  196.         if (vc->floors[i].floor_type == 0) {

  197.             av_free(vc->floors[i].data.t0.map[0]);

  198.             av_free(vc->floors[i].data.t0.map[1]);

  199.             av_free(vc->floors[i].data.t0.book_list);

  200.             av_free(vc->floors[i].data.t0.lsp);

  201.         } else {

  202.             av_free(vc->floors[i].data.t1.list);

  203.         }

  204.     }

  205.     av_freep(&vc->floors);

  206. 

  207.     for (i = 0; i < vc->mapping_count; ++i) {

  208.         av_free(vc->mappings[i].magnitude);

  209.         av_free(vc->mappings[i].angle);

  210.         av_free(vc->mappings[i].mux);

  211.     }

  212.     av_freep(&vc->mappings);

  213. }

  214. 

  215. // Parse setup header -------------------------------------------------

  216. 

  217. // Process codebooks part

  218. 

  219. static int vorbis_parse_setup_hdr_codebooks(vorbis_context *vc)

  220. {

  221.     uint_fast16_t cb;

  222.     uint8_t  *tmp_vlc_bits;

  223.     uint32_t *tmp_vlc_codes;

  224.     GetBitContext *gb = &vc->gb;

  225. 

  226.     vc->codebook_count = get_bits(gb, 8) + 1;

  227. 

  228.     AV_DEBUG(" Codebooks: %d \n", vc->codebook_count);

  229. 

  230.     vc->codebooks = av_mallocz(vc->codebook_count * sizeof(vorbis_codebook));

  231.     tmp_vlc_bits  = av_mallocz(V_MAX_VLCS * sizeof(uint8_t));

  232.     tmp_vlc_codes = av_mallocz(V_MAX_VLCS * sizeof(uint32_t));

  233. 

  234.     for (cb = 0; cb < vc->codebook_count; ++cb) {

  235.         vorbis_codebook *codebook_setup = &vc->codebooks[cb];

  236.         uint_fast8_t ordered;

  237.         uint_fast32_t t, used_entries = 0;

  238.         uint_fast32_t entries;

  239. 

  240.         AV_DEBUG(" %d. Codebook \n", cb);

  241. 

  242.         if (get_bits(gb, 24) != 0x564342) {

  243.             av_log(vc->avccontext, AV_LOG_ERROR, " %"PRIdFAST16". Codebook setup data corrupt. \n", cb);

  244.             goto error;

  245.         }

  246. 

  247.         codebook_setup->dimensions=get_bits(gb, 16);

  248.         if (codebook_setup->dimensions > 16 || codebook_setup->dimensions == 0) {

  249.             av_log(vc->avccontext, AV_LOG_ERROR, " %"PRIdFAST16". Codebook's dimension is invalid (%d). \n", cb, codebook_setup->dimensions);

  250.             goto error;

  251.         }

  252.         entries = get_bits(gb, 24);

  253.         if (entries > V_MAX_VLCS) {

  254.             av_log(vc->avccontext, AV_LOG_ERROR, " %"PRIdFAST16". Codebook has too many entries (%"PRIdFAST32"). \n", cb, entries);

  255.             goto error;

  256.         }

  257. 

  258.         ordered = get_bits1(gb);

  259. 

  260.         AV_DEBUG(" codebook_dimensions %d, codebook_entries %d \n", codebook_setup->dimensions, entries);

  261. 

  262.         if (!ordered) {

  263.             uint_fast16_t ce;

  264.             uint_fast8_t  flag;

  265.             uint_fast8_t  sparse = get_bits1(gb);

  266. 

  267.             AV_DEBUG(" not ordered \n");

  268. 

  269.             if (sparse) {

  270.                 AV_DEBUG(" sparse \n");

  271. 

  272.                 used_entries = 0;

  273.                 for (ce = 0; ce < entries; ++ce) {

  274.                     flag = get_bits1(gb);

  275.                     if (flag) {

  276.                         tmp_vlc_bits[ce] = get_bits(gb, 5) + 1;

  277.                         ++used_entries;

  278.                     } else

  279.                         tmp_vlc_bits[ce] = 0;

  280.                 }

  281.             } else {

  282.                 AV_DEBUG(" not sparse \n");

  283. 

  284.                 used_entries = entries;

  285.                 for (ce = 0; ce < entries; ++ce)

  286.                     tmp_vlc_bits[ce] = get_bits(gb, 5) + 1;

  287.             }

  288.         } else {

  289.             uint_fast16_t current_entry = 0;

  290.             uint_fast8_t current_length = get_bits(gb, 5)+1;

  291. 

  292.             AV_DEBUG(" ordered, current length: %d \n", current_length);  //FIXME

  293. 

  294.             used_entries = entries;

  295.             for (; current_entry < used_entries && current_length <= 32; ++current_length) {

  296.                 uint_fast16_t i, number;

  297. 

  298.                 AV_DEBUG(" number bits: %d ", ilog(entries - current_entry));

  299. 

  300.                 number = get_bits(gb, ilog(entries - current_entry));

  301. 

  302.                 AV_DEBUG(" number: %d \n", number);

  303. 

  304.                 for (i = current_entry; i < number+current_entry; ++i)

  305.                     if (i < used_entries)

  306.                         tmp_vlc_bits[i] = current_length;

  307. 

  308.                 current_entry+=number;

  309.             }

  310.             if (current_entry>used_entries) {

  311.                 av_log(vc->avccontext, AV_LOG_ERROR, " More codelengths than codes in codebook. \n");

  312.                 goto error;

  313.             }

  314.         }

  315. 

  316.         codebook_setup->lookup_type = get_bits(gb, 4);

  317. 

  318.         AV_DEBUG(" lookup type: %d : %s \n", codebook_setup->lookup_type, codebook_setup->lookup_type ? "vq" : "no lookup");

  319. 

  320. // If the codebook is used for (inverse) VQ, calculate codevectors.

  321. 

  322.         if (codebook_setup->lookup_type == 1) {

  323.             uint_fast16_t i, j, k;

  324.             uint_fast16_t codebook_lookup_values = ff_vorbis_nth_root(entries, codebook_setup->dimensions);

  325.             uint_fast16_t codebook_multiplicands[codebook_lookup_values];

  326. 

  327.             float codebook_minimum_value = vorbisfloat2float(get_bits_long(gb, 32));

  328.             float codebook_delta_value   = vorbisfloat2float(get_bits_long(gb, 32));

  329.             uint_fast8_t codebook_value_bits = get_bits(gb, 4)+1;

  330.             uint_fast8_t codebook_sequence_p = get_bits1(gb);

  331. 

  332.             AV_DEBUG(" We expect %d numbers for building the codevectors. \n", codebook_lookup_values);

  333.             AV_DEBUG("  delta %f minmum %f \n", codebook_delta_value, codebook_minimum_value);

  334. 

  335.             for (i = 0; i < codebook_lookup_values; ++i) {

  336.                 codebook_multiplicands[i] = get_bits(gb, codebook_value_bits);

  337. 

  338.                 AV_DEBUG(" multiplicands*delta+minmum : %e \n", (float)codebook_multiplicands[i]*codebook_delta_value+codebook_minimum_value);

  339.                 AV_DEBUG(" multiplicand %d \n", codebook_multiplicands[i]);

  340.             }

  341. 

  342. // Weed out unused vlcs and build codevector vector

  343.             codebook_setup->codevectors = used_entries ? av_mallocz(used_entries*codebook_setup->dimensions * sizeof(float)) : NULL;

  344.             for (j = 0, i = 0; i < entries; ++i) {

  345.                 uint_fast8_t dim = codebook_setup->dimensions;

  346. 

  347.                 if (tmp_vlc_bits[i]) {

  348.                     float last = 0.0;

  349.                     uint_fast32_t lookup_offset = i;

  350. 

  351. #ifdef V_DEBUG

  352.                     av_log(vc->avccontext, AV_LOG_INFO, "Lookup offset %d ,", i);

  353. #endif

  354. 

  355.                     for (k = 0; k < dim; ++k) {

  356.                         uint_fast32_t multiplicand_offset = lookup_offset % codebook_lookup_values;

  357.                         codebook_setup->codevectors[j * dim + k] = codebook_multiplicands[multiplicand_offset] * codebook_delta_value + codebook_minimum_value + last;

  358.                         if (codebook_sequence_p)

  359.                             last = codebook_setup->codevectors[j * dim + k];

  360.                         lookup_offset/=codebook_lookup_values;

  361.                     }

  362.                     tmp_vlc_bits[j] = tmp_vlc_bits[i];

  363. 

  364. #ifdef V_DEBUG

  365.                     av_log(vc->avccontext, AV_LOG_INFO, "real lookup offset %d, vector: ", j);

  366.                     for (k = 0; k < dim; ++k)

  367.                         av_log(vc->avccontext, AV_LOG_INFO, " %f ", codebook_setup->codevectors[j * dim + k]);

  368.                     av_log(vc->avccontext, AV_LOG_INFO, "\n");

  369. #endif

  370. 

  371.                     ++j;

  372.                 }

  373.             }

  374.             if (j != used_entries) {

  375.                 av_log(vc->avccontext, AV_LOG_ERROR, "Bug in codevector vector building code. \n");

  376.                 goto error;

  377.             }

  378.             entries = used_entries;

  379.         } else if (codebook_setup->lookup_type >= 2) {

  380.             av_log(vc->avccontext, AV_LOG_ERROR, "Codebook lookup type not supported. \n");

  381.             goto error;

  382.         }

  383. 

  384. // Initialize VLC table

  385.         if (ff_vorbis_len2vlc(tmp_vlc_bits, tmp_vlc_codes, entries)) {

  386.             av_log(vc->avccontext, AV_LOG_ERROR, " Invalid code lengths while generating vlcs. \n");

  387.             goto error;

  388.         }

  389.         codebook_setup->maxdepth = 0;

  390.         for (t = 0; t < entries; ++t)

  391.             if (tmp_vlc_bits[t] >= codebook_setup->maxdepth)

  392.                 codebook_setup->maxdepth = tmp_vlc_bits[t];

  393. 

  394.         if (codebook_setup->maxdepth > 3 * V_NB_BITS)

  395.             codebook_setup->nb_bits = V_NB_BITS2;

  396.         else

  397.             codebook_setup->nb_bits = V_NB_BITS;

  398. 

  399.         codebook_setup->maxdepth = (codebook_setup->maxdepth+codebook_setup->nb_bits - 1) / codebook_setup->nb_bits;

  400. 

  401.         if (init_vlc(&codebook_setup->vlc, codebook_setup->nb_bits, entries, tmp_vlc_bits, sizeof(*tmp_vlc_bits), sizeof(*tmp_vlc_bits), tmp_vlc_codes, sizeof(*tmp_vlc_codes), sizeof(*tmp_vlc_codes), INIT_VLC_LE)) {

  402.             av_log(vc->avccontext, AV_LOG_ERROR, " Error generating vlc tables. \n");

  403.             goto error;

  404.         }

  405.     }

  406. 

  407.     av_free(tmp_vlc_bits);

  408.     av_free(tmp_vlc_codes);

  409.     return 0;

  410. 

  411. // Error:

  412. error:

  413.     av_free(tmp_vlc_bits);

  414.     av_free(tmp_vlc_codes);

  415.     return -1;

  416. }

  417. 

  418. // Process time domain transforms part (unused in Vorbis I)

  419. 

  420. static int vorbis_parse_setup_hdr_tdtransforms(vorbis_context *vc)

  421. {

  422.     GetBitContext *gb = &vc->gb;

  423.     uint_fast8_t i;

  424.     uint_fast8_t vorbis_time_count = get_bits(gb, 6) + 1;

  425. 

  426.     for (i = 0; i < vorbis_time_count; ++i) {

  427.         uint_fast16_t vorbis_tdtransform = get_bits(gb, 16);

  428. 

  429.         AV_DEBUG(" Vorbis time domain transform %d: %d \n", vorbis_time_count, vorbis_tdtransform);

  430. 

  431.         if (vorbis_tdtransform) {

  432.             av_log(vc->avccontext, AV_LOG_ERROR, "Vorbis time domain transform data nonzero. \n");

  433.             return -1;

  434.         }

  435.     }

  436.     return 0;

  437. }

  438. 

  439. // Process floors part

  440. 

  441. static uint_fast8_t vorbis_floor0_decode(vorbis_context *vc,

  442.                                          vorbis_floor_data *vfu, float *vec);

  443. static void create_map(vorbis_context *vc, uint_fast8_t floor_number);

  444. static uint_fast8_t vorbis_floor1_decode(vorbis_context *vc,

  445.                                          vorbis_floor_data *vfu, float *vec);

  446. static int vorbis_parse_setup_hdr_floors(vorbis_context *vc)

  447. {

  448.     GetBitContext *gb = &vc->gb;

  449.     uint_fast16_t i,j,k;

  450. 

  451.     vc->floor_count = get_bits(gb, 6) + 1;

  452. 

  453.     vc->floors = av_mallocz(vc->floor_count * sizeof(vorbis_floor));

  454. 

  455.     for (i = 0; i < vc->floor_count; ++i) {

  456.         vorbis_floor *floor_setup = &vc->floors[i];

  457. 

  458.         floor_setup->floor_type = get_bits(gb, 16);

  459. 

  460.         AV_DEBUG(" %d. floor type %d \n", i, floor_setup->floor_type);

  461. 

  462.         if (floor_setup->floor_type == 1) {

  463.             uint_fast8_t  maximum_class = 0;

  464.             uint_fast8_t  rangebits;

  465.             uint_fast16_t floor1_values = 2;

  466. 

  467.             floor_setup->decode = vorbis_floor1_decode;

  468. 

  469.             floor_setup->data.t1.partitions = get_bits(gb, 5);

  470. 

  471.             AV_DEBUG(" %d.floor: %d partitions \n", i, floor_setup->data.t1.partitions);

  472. 

  473.             for (j = 0; j < floor_setup->data.t1.partitions; ++j) {

  474.                 floor_setup->data.t1.partition_class[j] = get_bits(gb, 4);

  475.                 if (floor_setup->data.t1.partition_class[j] > maximum_class)

  476.                     maximum_class = floor_setup->data.t1.partition_class[j];

  477. 

  478.                 AV_DEBUG(" %d. floor %d partition class %d \n", i, j, floor_setup->data.t1.partition_class[j]);

  479. 

  480.             }

  481. 

  482.             AV_DEBUG(" maximum class %d \n", maximum_class);

  483. 

  484.             floor_setup->data.t1.maximum_class = maximum_class;

  485. 

  486.             for (j = 0; j <= maximum_class; ++j) {

  487.                 floor_setup->data.t1.class_dimensions[j] = get_bits(gb, 3) + 1;

  488.                 floor_setup->data.t1.class_subclasses[j] = get_bits(gb, 2);

  489. 

  490.                 AV_DEBUG(" %d floor %d class dim: %d subclasses %d \n", i, j, floor_setup->data.t1.class_dimensions[j], floor_setup->data.t1.class_subclasses[j]);

  491. 

  492.                 if (floor_setup->data.t1.class_subclasses[j]) {

  493.                     int bits = get_bits(gb, 8);

  494.                     if (bits >= vc->codebook_count) {

  495.                         av_log(vc->avccontext, AV_LOG_ERROR, "Masterbook index %d is out of range.\n", bits);

  496.                         return -1;

  497.                     }

  498.                     floor_setup->data.t1.class_masterbook[j] = bits;

  499. 

  500.                     AV_DEBUG("   masterbook: %d \n", floor_setup->data.t1.class_masterbook[j]);

  501.                 }

  502. 

  503.                 for (k = 0; k < (1 << floor_setup->data.t1.class_subclasses[j]); ++k) {

  504.                     int16_t bits = get_bits(gb, 8) - 1;

  505.                     if (bits != -1 && bits >= vc->codebook_count) {

  506.                         av_log(vc->avccontext, AV_LOG_ERROR, "Subclass book index %d is out of range.\n", bits);

  507.                         return -1;

  508.                     }

  509.                     floor_setup->data.t1.subclass_books[j][k] = bits;

  510. 

  511.                     AV_DEBUG("    book %d. : %d \n", k, floor_setup->data.t1.subclass_books[j][k]);

  512.                 }

  513.             }

  514. 

  515.             floor_setup->data.t1.multiplier = get_bits(gb, 2) + 1;

  516.             floor_setup->data.t1.x_list_dim = 2;

  517. 

  518.             for (j = 0; j < floor_setup->data.t1.partitions; ++j)

  519.                 floor_setup->data.t1.x_list_dim+=floor_setup->data.t1.class_dimensions[floor_setup->data.t1.partition_class[j]];

  520. 

  521.             floor_setup->data.t1.list = av_mallocz(floor_setup->data.t1.x_list_dim * sizeof(vorbis_floor1_entry));

  522. 

  523. 

  524.             rangebits = get_bits(gb, 4);

  525.             floor_setup->data.t1.list[0].x = 0;

  526.             floor_setup->data.t1.list[1].x = (1 << rangebits);

  527. 

  528.             for (j = 0; j < floor_setup->data.t1.partitions; ++j) {

  529.                 for (k = 0; k < floor_setup->data.t1.class_dimensions[floor_setup->data.t1.partition_class[j]]; ++k, ++floor1_values) {

  530.                     floor_setup->data.t1.list[floor1_values].x = get_bits(gb, rangebits);

  531. 

  532.                     AV_DEBUG(" %d. floor1 Y coord. %d \n", floor1_values, floor_setup->data.t1.list[floor1_values].x);

  533.                 }

  534.             }

  535. 

  536. // Precalculate order of x coordinates - needed for decode

  537.             ff_vorbis_ready_floor1_list(floor_setup->data.t1.list, floor_setup->data.t1.x_list_dim);

  538.         } else if (floor_setup->floor_type == 0) {

  539.             uint_fast8_t max_codebook_dim = 0;

  540. 

  541.             floor_setup->decode = vorbis_floor0_decode;

  542. 

  543.             floor_setup->data.t0.order          = get_bits(gb,  8);

  544.             floor_setup->data.t0.rate           = get_bits(gb, 16);

  545.             floor_setup->data.t0.bark_map_size  = get_bits(gb, 16);

  546.             floor_setup->data.t0.amplitude_bits = get_bits(gb,  6);

  547.             /* zero would result in a div by zero later *

  548.              * 2^0 - 1 == 0                             */

  549.             if (floor_setup->data.t0.amplitude_bits == 0) {

  550.               av_log(vc->avccontext, AV_LOG_ERROR,

  551.                      "Floor 0 amplitude bits is 0.\n");

  552.               return -1;

  553.             }

  554.             floor_setup->data.t0.amplitude_offset = get_bits(gb, 8);

  555.             floor_setup->data.t0.num_books        = get_bits(gb, 4) + 1;

  556. 

  557.             /* allocate mem for booklist */

  558.             floor_setup->data.t0.book_list =

  559.                 av_malloc(floor_setup->data.t0.num_books);

  560.             if (!floor_setup->data.t0.book_list)

  561.                 return -1;

  562.             /* read book indexes */

  563.             {

  564.                 int idx;

  565.                 uint_fast8_t book_idx;

  566.                 for (idx = 0; idx < floor_setup->data.t0.num_books; ++idx) {

  567.                     book_idx = get_bits(gb, 8);

  568.                     if (book_idx >= vc->codebook_count)

  569.                         return -1;

  570.                     floor_setup->data.t0.book_list[idx] = book_idx;

  571.                     if (vc->codebooks[book_idx].dimensions > max_codebook_dim)

  572.                         max_codebook_dim = vc->codebooks[book_idx].dimensions;

  573.                 }

  574.             }

  575. 

  576.             create_map(vc, i);

  577. 

  578.             /* allocate mem for lsp coefficients */

  579.             {

  580.                 /* codebook dim is for padding if codebook dim doesn't *

  581.                  * divide order+1 then we need to read more data       */

  582.                 floor_setup->data.t0.lsp =

  583.                     av_malloc((floor_setup->data.t0.order+1 + max_codebook_dim)

  584.                               * sizeof(float));

  585.                 if (!floor_setup->data.t0.lsp)

  586.                     return -1;

  587.             }

  588. 

  589. #ifdef V_DEBUG /* debug output parsed headers */

  590.             AV_DEBUG("floor0 order: %u\n", floor_setup->data.t0.order);

  591.             AV_DEBUG("floor0 rate: %u\n", floor_setup->data.t0.rate);

  592.             AV_DEBUG("floor0 bark map size: %u\n",

  593.               floor_setup->data.t0.bark_map_size);

  594.             AV_DEBUG("floor0 amplitude bits: %u\n",

  595.               floor_setup->data.t0.amplitude_bits);

  596.             AV_DEBUG("floor0 amplitude offset: %u\n",

  597.               floor_setup->data.t0.amplitude_offset);

  598.             AV_DEBUG("floor0 number of books: %u\n",

  599.               floor_setup->data.t0.num_books);

  600.             AV_DEBUG("floor0 book list pointer: %p\n",

  601.               floor_setup->data.t0.book_list);

  602.             {

  603.               int idx;

  604.               for (idx = 0; idx < floor_setup->data.t0.num_books; ++idx) {

  605.                   AV_DEBUG("  Book %d: %u\n",

  606.                            idx+1,

  607.                            floor_setup->data.t0.book_list[idx]);

  608.               }

  609.             }

  610. #endif

  611.         } else {

  612.             av_log(vc->avccontext, AV_LOG_ERROR, "Invalid floor type!\n");

  613.             return -1;

  614.         }

  615.     }

  616.     return 0;

  617. }

  618. 

  619. // Process residues part

  620. 

  621. static int vorbis_parse_setup_hdr_residues(vorbis_context *vc)

  622. {

  623.     GetBitContext *gb = &vc->gb;

  624.     uint_fast8_t i, j, k;

  625. 

  626.     vc->residue_count = get_bits(gb, 6)+1;

  627.     vc->residues      = av_mallocz(vc->residue_count * sizeof(vorbis_residue));

  628. 

  629.     AV_DEBUG(" There are %d residues. \n", vc->residue_count);

  630. 

  631.     for (i = 0; i < vc->residue_count; ++i) {

  632.         vorbis_residue *res_setup = &vc->residues[i];

  633.         uint_fast8_t cascade[64];

  634.         uint_fast8_t high_bits;

  635.         uint_fast8_t low_bits;

  636. 

  637.         res_setup->type = get_bits(gb, 16);

  638. 

  639.         AV_DEBUG(" %d. residue type %d \n", i, res_setup->type);

  640. 

  641.         res_setup->begin          = get_bits(gb, 24);

  642.         res_setup->end            = get_bits(gb, 24);

  643.         res_setup->partition_size = get_bits(gb, 24) + 1;

  644.         /* Validations to prevent a buffer overflow later. */

  645.         if (res_setup->begin>res_setup->end ||

  646.             res_setup->end>vc->blocksize[1] / (res_setup->type == 2 ? 1 : 2) ||

  647.             (res_setup->end-res_setup->begin) / res_setup->partition_size > V_MAX_PARTITIONS) {

  648.             av_log(vc->avccontext, AV_LOG_ERROR, "partition out of bounds: type, begin, end, size, blocksize: %"PRIdFAST16", %"PRIdFAST32", %"PRIdFAST32", %"PRIdFAST32", %"PRIdFAST32"\n", res_setup->type, res_setup->begin, res_setup->end, res_setup->partition_size, vc->blocksize[1] / 2);

  649.             return -1;

  650.         }

  651. 

  652.         res_setup->classifications = get_bits(gb, 6) + 1;

  653.         res_setup->classbook = get_bits(gb, 8);

  654.         if (res_setup->classbook >= vc->codebook_count) {

  655.             av_log(vc->avccontext, AV_LOG_ERROR, "classbook value %d out of range. \n", res_setup->classbook);

  656.             return -1;

  657.         }

  658. 

  659.         AV_DEBUG("    begin %d end %d part.size %d classif.s %d classbook %d \n", res_setup->begin, res_setup->end, res_setup->partition_size,

  660.           res_setup->classifications, res_setup->classbook);

  661. 

  662.         for (j = 0; j < res_setup->classifications; ++j) {

  663.             high_bits = 0;

  664.             low_bits  = get_bits(gb, 3);

  665.             if (get_bits1(gb))

  666.                 high_bits = get_bits(gb, 5);

  667.             cascade[j] = (high_bits << 3) + low_bits;

  668. 

  669.             AV_DEBUG("     %d class casscade depth: %d \n", j, ilog(cascade[j]));

  670.         }

  671. 

  672.         res_setup->maxpass = 0;

  673.         for (j = 0; j < res_setup->classifications; ++j) {

  674.             for (k = 0; k < 8; ++k) {

  675.                 if (cascade[j]&(1 << k)) {

  676.                     int bits = get_bits(gb, 8);

  677.                     if (bits >= vc->codebook_count) {

  678.                         av_log(vc->avccontext, AV_LOG_ERROR, "book value %d out of range. \n", bits);

  679.                         return -1;

  680.                     }

  681.                     res_setup->books[j][k] = bits;

  682. 

  683.                     AV_DEBUG("     %d class casscade depth %d book: %d \n", j, k, res_setup->books[j][k]);

  684. 

  685.                     if (k>res_setup->maxpass)

  686.                         res_setup->maxpass = k;

  687.                 } else {

  688.                     res_setup->books[j][k] = -1;

  689.                 }

  690.             }

  691.         }

  692.     }

  693.     return 0;

  694. }

  695. 

  696. // Process mappings part

  697. 

  698. static int vorbis_parse_setup_hdr_mappings(vorbis_context *vc)

  699. {

  700.     GetBitContext *gb = &vc->gb;

  701.     uint_fast8_t i, j;

  702. 

  703.     vc->mapping_count = get_bits(gb, 6)+1;

  704.     vc->mappings      = av_mallocz(vc->mapping_count * sizeof(vorbis_mapping));

  705. 

  706.     AV_DEBUG(" There are %d mappings. \n", vc->mapping_count);

  707. 

  708.     for (i = 0; i < vc->mapping_count; ++i) {

  709.         vorbis_mapping *mapping_setup = &vc->mappings[i];

  710. 

  711.         if (get_bits(gb, 16)) {

  712.             av_log(vc->avccontext, AV_LOG_ERROR, "Other mappings than type 0 are not compliant with the Vorbis I specification. \n");

  713.             return -1;

  714.         }

  715.         if (get_bits1(gb)) {

  716.             mapping_setup->submaps = get_bits(gb, 4) + 1;

  717.         } else {

  718.             mapping_setup->submaps = 1;

  719.         }

  720. 

  721.         if (get_bits1(gb)) {

  722.             mapping_setup->coupling_steps = get_bits(gb, 8) + 1;

  723.             mapping_setup->magnitude      = av_mallocz(mapping_setup->coupling_steps * sizeof(uint_fast8_t));

  724.             mapping_setup->angle          = av_mallocz(mapping_setup->coupling_steps * sizeof(uint_fast8_t));

  725.             for (j = 0; j < mapping_setup->coupling_steps; ++j) {

  726.                 mapping_setup->magnitude[j] = get_bits(gb, ilog(vc->audio_channels - 1));

  727.                 mapping_setup->angle[j] = get_bits(gb, ilog(vc->audio_channels - 1));

  728.                 if (mapping_setup->magnitude[j] >= vc->audio_channels) {

  729.                     av_log(vc->avccontext, AV_LOG_ERROR, "magnitude channel %d out of range. \n", mapping_setup->magnitude[j]);

  730.                     return -1;

  731.                 }

  732.                 if (mapping_setup->angle[j] >= vc->audio_channels) {

  733.                     av_log(vc->avccontext, AV_LOG_ERROR, "angle channel %d out of range. \n", mapping_setup->angle[j]);

  734.                     return -1;

  735.                 }

  736.             }

  737.         } else {

  738.             mapping_setup->coupling_steps = 0;

  739.         }

  740. 

  741.         AV_DEBUG("   %d mapping coupling steps: %d \n", i, mapping_setup->coupling_steps);

  742. 

  743.         if (get_bits(gb, 2)) {

  744.             av_log(vc->avccontext, AV_LOG_ERROR, "%d. mapping setup data invalid. \n", i);

  745.             return -1; // following spec.

  746.         }

  747. 

  748.         if (mapping_setup->submaps>1) {

  749.             mapping_setup->mux = av_mallocz(vc->audio_channels * sizeof(uint_fast8_t));

  750.             for (j = 0; j < vc->audio_channels; ++j)

  751.                 mapping_setup->mux[j] = get_bits(gb, 4);

  752.         }

  753. 

  754.         for (j = 0; j < mapping_setup->submaps; ++j) {

  755.             int bits;

  756.             skip_bits(gb, 8); // FIXME check?

  757.             bits = get_bits(gb, 8);

  758.             if (bits >= vc->floor_count) {

  759.                 av_log(vc->avccontext, AV_LOG_ERROR, "submap floor value %d out of range. \n", bits);

  760.                 return -1;

  761.             }

  762.             mapping_setup->submap_floor[j] = bits;

  763.             bits = get_bits(gb, 8);

  764.             if (bits >= vc->residue_count) {

  765.                 av_log(vc->avccontext, AV_LOG_ERROR, "submap residue value %d out of range. \n", bits);

  766.                 return -1;

  767.             }

  768.             mapping_setup->submap_residue[j] = bits;

  769. 

  770.             AV_DEBUG("   %d mapping %d submap : floor %d, residue %d \n", i, j, mapping_setup->submap_floor[j], mapping_setup->submap_residue[j]);

  771.         }

  772.     }

  773.     return 0;

  774. }

  775. 

  776. // Process modes part

  777. 

  778. static void create_map(vorbis_context *vc, uint_fast8_t floor_number)

  779. {

  780.     vorbis_floor *floors = vc->floors;

  781.     vorbis_floor0 *vf;

  782.     int idx;

  783.     int_fast8_t blockflag;

  784.     int_fast32_t *map;

  785.     int_fast32_t n; //TODO: could theoretically be smaller?

  786. 

  787.     for (blockflag = 0; blockflag < 2; ++blockflag) {

  788.         n = vc->blocksize[blockflag] / 2;

  789.         floors[floor_number].data.t0.map[blockflag] =

  790.             av_malloc((n+1) * sizeof(int_fast32_t)); // n + sentinel

  791. 

  792.         map =  floors[floor_number].data.t0.map[blockflag];

  793.         vf  = &floors[floor_number].data.t0;

  794. 

  795.         for (idx = 0; idx < n; ++idx) {

  796.             map[idx] = floor(BARK((vf->rate * idx) / (2.0f * n)) *

  797.                              ((vf->bark_map_size) /

  798.                               BARK(vf->rate / 2.0f)));

  799.             if (vf->bark_map_size-1 < map[idx])

  800.                 map[idx] = vf->bark_map_size - 1;

  801.         }

  802.         map[n] = -1;

  803.         vf->map_size[blockflag] = n;

  804.     }

  805. 

  806. #   ifdef V_DEBUG

  807.     for (idx = 0; idx <= n; ++idx) {

  808.         AV_DEBUG("floor0 map: map at pos %d is %d\n",

  809.                  idx, map[idx]);

  810.     }

  811. #   endif

  812. }

  813. 

  814. static int vorbis_parse_setup_hdr_modes(vorbis_context *vc)

  815. {

  816.     GetBitContext *gb = &vc->gb;

  817.     uint_fast8_t i;

  818. 

  819.     vc->mode_count = get_bits(gb, 6) + 1;

  820.     vc->modes      = av_mallocz(vc->mode_count * sizeof(vorbis_mode));

  821. 

  822.     AV_DEBUG(" There are %d modes.\n", vc->mode_count);

  823. 

  824.     for (i = 0; i < vc->mode_count; ++i) {

  825.         vorbis_mode *mode_setup = &vc->modes[i];

  826. 

  827.         mode_setup->blockflag     = get_bits1(gb);

  828.         mode_setup->windowtype    = get_bits(gb, 16); //FIXME check

  829.         mode_setup->transformtype = get_bits(gb, 16); //FIXME check

  830.         mode_setup->mapping       = get_bits(gb,  8);

  831.         if (mode_setup->mapping >= vc->mapping_count) {

  832.             av_log(vc->avccontext, AV_LOG_ERROR, "mode mapping value %d out of range. \n", mode_setup->mapping);

  833.             return -1;

  834.         }

  835. 

  836.         AV_DEBUG(" %d mode: blockflag %d, windowtype %d, transformtype %d, mapping %d \n", i, mode_setup->blockflag, mode_setup->windowtype, mode_setup->transformtype, mode_setup->mapping);

  837.     }

  838.     return 0;

  839. }

  840. 

  841. // Process the whole setup header using the functions above

  842. 

  843. static int vorbis_parse_setup_hdr(vorbis_context *vc)

  844. {

  845.     GetBitContext *gb = &vc->gb;

  846. 

  847.     if ((get_bits(gb, 8) != 'v') || (get_bits(gb, 8) != 'o') ||

  848.         (get_bits(gb, 8) != 'r') || (get_bits(gb, 8) != 'b') ||

  849.         (get_bits(gb, 8) != 'i') || (get_bits(gb, 8) != 's')) {

  850.         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (no vorbis signature). \n");

  851.         return -1;

  852.     }

  853. 

  854.     if (vorbis_parse_setup_hdr_codebooks(vc)) {

  855.         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (codebooks). \n");

  856.         return -2;

  857.     }

  858.     if (vorbis_parse_setup_hdr_tdtransforms(vc)) {

  859.         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (time domain transforms). \n");

  860.         return -3;

  861.     }

  862.     if (vorbis_parse_setup_hdr_floors(vc)) {

  863.         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (floors). \n");

  864.         return -4;

  865.     }

  866.     if (vorbis_parse_setup_hdr_residues(vc)) {

  867.         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (residues). \n");

  868.         return -5;

  869.     }

  870.     if (vorbis_parse_setup_hdr_mappings(vc)) {

  871.         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (mappings). \n");

  872.         return -6;

  873.     }

  874.     if (vorbis_parse_setup_hdr_modes(vc)) {

  875.         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (modes). \n");

  876.         return -7;

  877.     }

  878.     if (!get_bits1(gb)) {

  879.         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (framing flag). \n");

  880.         return -8; // framing flag bit unset error

  881.     }

  882. 

  883.     return 0;

  884. }

  885. 

  886. // Process the identification header

  887. 

  888. static int vorbis_parse_id_hdr(vorbis_context *vc)

  889. {

  890.     GetBitContext *gb = &vc->gb;

  891.     uint_fast8_t bl0, bl1;

  892. 

  893.     if ((get_bits(gb, 8) != 'v') || (get_bits(gb, 8) != 'o') ||

  894.         (get_bits(gb, 8) != 'r') || (get_bits(gb, 8) != 'b') ||

  895.         (get_bits(gb, 8) != 'i') || (get_bits(gb, 8) != 's')) {

  896.         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis id header packet corrupt (no vorbis signature). \n");

  897.         return -1;

  898.     }

  899. 

  900.     vc->version        = get_bits_long(gb, 32);    //FIXME check 0

  901.     vc->audio_channels = get_bits(gb, 8);

  902.     if (vc->audio_channels <= 0) {

  903.         av_log(vc->avccontext, AV_LOG_ERROR, "Invalid number of channels\n");

  904.         return -1;

  905.     }

  906.     vc->audio_samplerate = get_bits_long(gb, 32);

  907.     if (vc->audio_samplerate <= 0) {

  908.         av_log(vc->avccontext, AV_LOG_ERROR, "Invalid samplerate\n");

  909.         return -1;

  910.     }

  911.     vc->bitrate_maximum = get_bits_long(gb, 32);

  912.     vc->bitrate_nominal = get_bits_long(gb, 32);

  913.     vc->bitrate_minimum = get_bits_long(gb, 32);

  914.     bl0 = get_bits(gb, 4);

  915.     bl1 = get_bits(gb, 4);

  916.     vc->blocksize[0] = (1 << bl0);

  917.     vc->blocksize[1] = (1 << bl1);

  918.     if (bl0 > 13 || bl0 < 6 || bl1 > 13 || bl1 < 6 || bl1 < bl0) {

  919.         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis id header packet corrupt (illegal blocksize). \n");

  920.         return -3;

  921.     }

  922.     // output format int16

  923.     if (vc->blocksize[1] / 2 * vc->audio_channels * 2 > AVCODEC_MAX_AUDIO_FRAME_SIZE) {

  924.         av_log(vc->avccontext, AV_LOG_ERROR, "Vorbis channel count makes "

  925.                "output packets too large.\n");

  926.         return -4;

  927.     }

  928.     vc->win[0] = ff_vorbis_vwin[bl0 - 6];

  929.     vc->win[1] = ff_vorbis_vwin[bl1 - 6];

  930. 

  931.     if ((get_bits1(gb)) == 0) {

  932.         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis id header packet corrupt (framing flag not set). \n");

  933.         return -2;

  934.     }

  935. 

  936.     vc->channel_residues =  av_malloc((vc->blocksize[1]  / 2) * vc->audio_channels * sizeof(float));

  937.     vc->channel_floors   =  av_malloc((vc->blocksize[1]  / 2) * vc->audio_channels * sizeof(float));

  938.     vc->saved            =  av_mallocz((vc->blocksize[1] / 4) * vc->audio_channels * sizeof(float));

  939.     vc->previous_window  = 0;

  940. 

  941.     ff_mdct_init(&vc->mdct[0], bl0, 1, vc->exp_bias ? -(1 << 15) : -1.0);

  942.     ff_mdct_init(&vc->mdct[1], bl1, 1, vc->exp_bias ? -(1 << 15) : -1.0);

  943. 

  944.     AV_DEBUG(" vorbis version %d \n audio_channels %d \n audio_samplerate %d \n bitrate_max %d \n bitrate_nom %d \n bitrate_min %d \n blk_0 %d blk_1 %d \n ",

  945.             vc->version, vc->audio_channels, vc->audio_samplerate, vc->bitrate_maximum, vc->bitrate_nominal, vc->bitrate_minimum, vc->blocksize[0], vc->blocksize[1]);

  946. 

  947. /*

  948.     BLK = vc->blocksize[0];

  949.     for (i = 0; i < BLK / 2; ++i) {

  950.         vc->win[0][i] = sin(0.5*3.14159265358*(sin(((float)i + 0.5) / (float)BLK*3.14159265358))*(sin(((float)i + 0.5) / (float)BLK*3.14159265358)));

  951.     }

  952. */

  953. 

  954.     return 0;

  955. }

  956. 

  957. // Process the extradata using the functions above (identification header, setup header)

  958. 

  959. static av_cold int vorbis_decode_init(AVCodecContext *avccontext)

  960. {

  961.     vorbis_context *vc = avccontext->priv_data ;

  962.     uint8_t *headers   = avccontext->extradata;

  963.     int headers_len    = avccontext->extradata_size;

  964.     uint8_t *header_start[3];

  965.     int header_len[3];

  966.     GetBitContext *gb = &(vc->gb);

  967.     int hdr_type;

  968. 

  969.     vc->avccontext = avccontext;

  970.     dsputil_init(&vc->dsp, avccontext);

  971. 

  972.     if (vc->dsp.float_to_int16_interleave == ff_float_to_int16_interleave_c) {

  973.         vc->add_bias = 385;

  974.         vc->exp_bias = 0;

  975.     } else {

  976.         vc->add_bias = 0;

  977.         vc->exp_bias = 15 << 23;

  978.     }

  979. 

  980.     if (!headers_len) {

  981.         av_log(avccontext, AV_LOG_ERROR, "Extradata corrupt.\n");

  982.         return -1;

  983.     }

  984. 

  985.     if (ff_split_xiph_headers(headers, headers_len, 30, header_start, header_len) < 0) {

  986.         av_log(avccontext, AV_LOG_ERROR, "Extradata corrupt.\n");

  987.         return -1;

  988.     }

  989. 

  990.     init_get_bits(gb, header_start[0], header_len[0]*8);

  991.     hdr_type = get_bits(gb, 8);

  992.     if (hdr_type != 1) {

  993.         av_log(avccontext, AV_LOG_ERROR, "First header is not the id header.\n");

  994.         return -1;

  995.     }

  996.     if (vorbis_parse_id_hdr(vc)) {

  997.         av_log(avccontext, AV_LOG_ERROR, "Id header corrupt.\n");

  998.         vorbis_free(vc);

  999.         return -1;

  1000.     }

  1001. 

  1002.     init_get_bits(gb, header_start[2], header_len[2]*8);

  1003.     hdr_type = get_bits(gb, 8);

  1004.     if (hdr_type != 5) {

  1005.         av_log(avccontext, AV_LOG_ERROR, "Third header is not the setup header.\n");

  1006.         vorbis_free(vc);

  1007.         return -1;

  1008.     }

  1009.     if (vorbis_parse_setup_hdr(vc)) {

  1010.         av_log(avccontext, AV_LOG_ERROR, "Setup header corrupt.\n");

  1011.         vorbis_free(vc);

  1012.         return -1;

  1013.     }

  1014. 

  1015.     if (vc->audio_channels > 6)

  1016.         avccontext->channel_layout = 0;

  1017.     else

  1018.         avccontext->channel_layout = ff_vorbis_channel_layouts[vc->audio_channels - 1];

  1019. 

  1020.     avccontext->channels    = vc->audio_channels;

  1021.     avccontext->sample_rate = vc->audio_samplerate;

  1022.     avccontext->frame_size  = FFMIN(vc->blocksize[0], vc->blocksize[1]) >> 2;

  1023.     avccontext->sample_fmt  = SAMPLE_FMT_S16;

  1024. 

  1025.     return 0 ;

  1026. }

  1027. 

  1028. // Decode audiopackets -------------------------------------------------

  1029. 

  1030. // Read and decode floor

  1031. 

  1032. static uint_fast8_t vorbis_floor0_decode(vorbis_context *vc,

  1033.                                          vorbis_floor_data *vfu, float *vec)

  1034. {

  1035.     vorbis_floor0 *vf = &vfu->t0;

  1036.     float *lsp = vf->lsp;

  1037.     uint_fast32_t amplitude;

  1038.     uint_fast32_t book_idx;

  1039.     uint_fast8_t blockflag = vc->modes[vc->mode_number].blockflag;

  1040. 

  1041.     amplitude = get_bits(&vc->gb, vf->amplitude_bits);

  1042.     if (amplitude > 0) {

  1043.         float last = 0;

  1044.         uint_fast16_t lsp_len = 0;

  1045.         uint_fast16_t idx;

  1046.         vorbis_codebook codebook;

  1047. 

  1048.         book_idx = get_bits(&vc->gb, ilog(vf->num_books));

  1049.         if (book_idx >= vf->num_books) {

  1050.             av_log(vc->avccontext, AV_LOG_ERROR,

  1051.                     "floor0 dec: booknumber too high!\n");

  1052.             book_idx =  0;

  1053.             //FIXME: look above

  1054.         }

  1055.         AV_DEBUG("floor0 dec: booknumber: %u\n", book_idx);

  1056.         codebook = vc->codebooks[vf->book_list[book_idx]];

  1057. 

  1058.         while (lsp_len<vf->order) {

  1059.             int vec_off;

  1060. 

  1061.             AV_DEBUG("floor0 dec: book dimension: %d\n", codebook.dimensions);

  1062.             AV_DEBUG("floor0 dec: maximum depth: %d\n", codebook.maxdepth);

  1063.             /* read temp vector */

  1064.             vec_off = get_vlc2(&vc->gb, codebook.vlc.table,

  1065.                                codebook.nb_bits, codebook.maxdepth)

  1066.                       * codebook.dimensions;

  1067.             AV_DEBUG("floor0 dec: vector offset: %d\n", vec_off);

  1068.             /* copy each vector component and add last to it */

  1069.             for (idx = 0; idx < codebook.dimensions; ++idx)

  1070.                 lsp[lsp_len+idx] = codebook.codevectors[vec_off+idx] + last;

  1071.             last = lsp[lsp_len+idx-1]; /* set last to last vector component */

  1072. 

  1073.             lsp_len += codebook.dimensions;

  1074.         }

  1075. #ifdef V_DEBUG

  1076.         /* DEBUG: output lsp coeffs */

  1077.         {

  1078.             int idx;

  1079.             for (idx = 0; idx < lsp_len; ++idx)

  1080.                 AV_DEBUG("floor0 dec: coeff at %d is %f\n", idx, lsp[idx]);

  1081.         }

  1082. #endif

  1083. 

  1084.         /* synthesize floor output vector */

  1085.         {

  1086.             int i;

  1087.             int order = vf->order;

  1088.             float wstep = M_PI / vf->bark_map_size;

  1089. 

  1090.             for (i = 0; i < order; i++)

  1091.                 lsp[i] = 2.0f * cos(lsp[i]);

  1092. 

  1093.             AV_DEBUG("floor0 synth: map_size = %d; m = %d; wstep = %f\n",

  1094.                      vf->map_size, order, wstep);

  1095. 

  1096.             i = 0;

  1097.             while (i < vf->map_size[blockflag]) {

  1098.                 int j, iter_cond = vf->map[blockflag][i];

  1099.                 float p = 0.5f;

  1100.                 float q = 0.5f;

  1101.                 float two_cos_w = 2.0f * cos(wstep * iter_cond); // needed all times

  1102. 

  1103.                 /* similar part for the q and p products */

  1104.                 for (j = 0; j + 1 < order; j += 2) {

  1105.                     q *= lsp[j]     - two_cos_w;

  1106.                     p *= lsp[j + 1] - two_cos_w;

  1107.                 }

  1108.                 if (j == order) { // even order

  1109.                     p *= p * (2.0f - two_cos_w);

  1110.                     q *= q * (2.0f + two_cos_w);

  1111.                 } else { // odd order

  1112.                     q *= two_cos_w-lsp[j]; // one more time for q

  1113. 

  1114.                     /* final step and square */

  1115.                     p *= p * (4.f - two_cos_w * two_cos_w);

  1116.                     q *= q;

  1117.                 }

  1118. 

  1119.                 /* calculate linear floor value */

  1120.                 {

  1121.                     q = exp((((amplitude*vf->amplitude_offset) /

  1122.                               (((1 << vf->amplitude_bits) - 1) * sqrt(p + q)))

  1123.                              - vf->amplitude_offset) * .11512925f);

  1124.                 }

  1125. 

  1126.                 /* fill vector */

  1127.                 do {

  1128.                     vec[i] = q; ++i;

  1129.                 } while (vf->map[blockflag][i] == iter_cond);

  1130.             }

  1131.         }

  1132.     } else {

  1133.         /* this channel is unused */

  1134.         return 1;

  1135.     }

  1136. 

  1137.     AV_DEBUG(" Floor0 decoded\n");

  1138. 

  1139.     return 0;

  1140. }

  1141. 

  1142. static uint_fast8_t vorbis_floor1_decode(vorbis_context *vc,

  1143.                                          vorbis_floor_data *vfu, float *vec)

  1144. {

  1145.     vorbis_floor1 *vf = &vfu->t1;

  1146.     GetBitContext *gb = &vc->gb;

  1147.     uint_fast16_t range_v[4] = { 256, 128, 86, 64 };

  1148.     uint_fast16_t range = range_v[vf->multiplier-1];

  1149.     uint_fast16_t floor1_Y[vf->x_list_dim];

  1150.     uint_fast16_t floor1_Y_final[vf->x_list_dim];

  1151.     int floor1_flag[vf->x_list_dim];

  1152.     uint_fast8_t class_;

  1153.     uint_fast8_t cdim;

  1154.     uint_fast8_t cbits;

  1155.     uint_fast8_t csub;

  1156.     uint_fast8_t cval;

  1157.     int_fast16_t book;

  1158.     uint_fast16_t offset;

  1159.     uint_fast16_t i,j;

  1160.     /*u*/int_fast16_t adx, ady, off, predicted; // WTF ? dy/adx =  (unsigned)dy/adx ?

  1161.     int_fast16_t dy, err;

  1162. 

  1163. 

  1164.     if (!get_bits1(gb)) // silence

  1165.         return 1;

  1166. 

  1167. // Read values (or differences) for the floor's points

  1168. 

  1169.     floor1_Y[0] = get_bits(gb, ilog(range - 1));

  1170.     floor1_Y[1] = get_bits(gb, ilog(range - 1));

  1171. 

  1172.     AV_DEBUG("floor 0 Y %d floor 1 Y %d \n", floor1_Y[0], floor1_Y[1]);

  1173. 

  1174.     offset = 2;

  1175.     for (i = 0; i < vf->partitions; ++i) {

  1176.         class_ = vf->partition_class[i];

  1177.         cdim   = vf->class_dimensions[class_];

  1178.         cbits  = vf->class_subclasses[class_];

  1179.         csub = (1 << cbits) - 1;

  1180.         cval = 0;

  1181. 

  1182.         AV_DEBUG("Cbits %d \n", cbits);

  1183. 

  1184.         if (cbits) // this reads all subclasses for this partition's class

  1185.             cval = get_vlc2(gb, vc->codebooks[vf->class_masterbook[class_]].vlc.table,

  1186.                             vc->codebooks[vf->class_masterbook[class_]].nb_bits, 3);

  1187. 

  1188.         for (j = 0; j < cdim; ++j) {

  1189.             book = vf->subclass_books[class_][cval & csub];

  1190. 

  1191.             AV_DEBUG("book %d Cbits %d cval %d  bits:%d \n", book, cbits, cval, get_bits_count(gb));

  1192. 

  1193.             cval = cval >> cbits;

  1194.             if (book > -1) {

  1195.                 floor1_Y[offset+j] = get_vlc2(gb, vc->codebooks[book].vlc.table,

  1196.                 vc->codebooks[book].nb_bits, 3);

  1197.             } else {

  1198.                 floor1_Y[offset+j] = 0;

  1199.             }

  1200. 

  1201.             AV_DEBUG(" floor(%d) = %d \n", vf->list[offset+j].x, floor1_Y[offset+j]);

  1202.         }

  1203.         offset+=cdim;

  1204.     }

  1205. 

  1206. // Amplitude calculation from the differences

  1207. 

  1208.     floor1_flag[0] = 1;

  1209.     floor1_flag[1] = 1;

  1210.     floor1_Y_final[0] = floor1_Y[0];

  1211.     floor1_Y_final[1] = floor1_Y[1];

  1212. 

  1213.     for (i = 2; i < vf->x_list_dim; ++i) {

  1214.         uint_fast16_t val, highroom, lowroom, room;

  1215.         uint_fast16_t high_neigh_offs;

  1216.         uint_fast16_t low_neigh_offs;

  1217. 

  1218.         low_neigh_offs  = vf->list[i].low;

  1219.         high_neigh_offs = vf->list[i].high;

  1220.         dy  = floor1_Y_final[high_neigh_offs] - floor1_Y_final[low_neigh_offs];  // render_point begin

  1221.         adx = vf->list[high_neigh_offs].x - vf->list[low_neigh_offs].x;

  1222.         ady = FFABS(dy);

  1223.         err = ady * (vf->list[i].x - vf->list[low_neigh_offs].x);

  1224.         off = (int16_t)err / (int16_t)adx;

  1225.         if (dy < 0) {

  1226.             predicted = floor1_Y_final[low_neigh_offs] - off;

  1227.         } else {

  1228.             predicted = floor1_Y_final[low_neigh_offs] + off;

  1229.         } // render_point end

  1230. 

  1231.         val = floor1_Y[i];

  1232.         highroom = range-predicted;

  1233.         lowroom  = predicted;

  1234.         if (highroom < lowroom) {

  1235.             room = highroom * 2;

  1236.         } else {

  1237.             room = lowroom * 2;   // SPEC mispelling

  1238.         }

  1239.         if (val) {

  1240.             floor1_flag[low_neigh_offs]  = 1;

  1241.             floor1_flag[high_neigh_offs] = 1;

  1242.             floor1_flag[i]               = 1;

  1243.             if (val >= room) {

  1244.                 if (highroom > lowroom) {

  1245.                     floor1_Y_final[i] = val - lowroom + predicted;

  1246.                 } else {

  1247.                     floor1_Y_final[i] = predicted - val + highroom - 1;

  1248.                 }

  1249.             } else {

  1250.                 if (val & 1) {

  1251.                     floor1_Y_final[i] = predicted - (val + 1) / 2;

  1252.                 } else {

  1253.                     floor1_Y_final[i] = predicted + val / 2;

  1254.                 }

  1255.             }

  1256.         } else {

  1257.             floor1_flag[i]    = 0;

  1258.             floor1_Y_final[i] = predicted;

  1259.         }

  1260. 

  1261.         AV_DEBUG(" Decoded floor(%d) = %d / val %d \n", vf->list[i].x, floor1_Y_final[i], val);

  1262.     }

  1263. 

  1264. // Curve synth - connect the calculated dots and convert from dB scale FIXME optimize ?

  1265. 

  1266.     ff_vorbis_floor1_render_list(vf->list, vf->x_list_dim, floor1_Y_final, floor1_flag, vf->multiplier, vec, vf->list[1].x);

  1267. 

  1268.     AV_DEBUG(" Floor decoded\n");

  1269. 

  1270.     return 0;

  1271. }

  1272. 

  1273. // Read and decode residue

  1274. 

  1275. static av_always_inline int vorbis_residue_decode_internal(vorbis_context *vc,

  1276.                                                            vorbis_residue *vr,

  1277.                                                            uint_fast8_t ch,

  1278.                                                            uint_fast8_t *do_not_decode,

  1279.                                                            float *vec,

  1280.                                                            uint_fast16_t vlen,

  1281.                                                            int vr_type)

  1282. {

  1283.     GetBitContext *gb = &vc->gb;

  1284.     uint_fast8_t c_p_c = vc->codebooks[vr->classbook].dimensions;

  1285.     uint_fast16_t n_to_read = vr->end-vr->begin;

  1286.     uint_fast16_t ptns_to_read = n_to_read/vr->partition_size;

  1287.     uint_fast8_t classifs[ptns_to_read*vc->audio_channels];

  1288.     uint_fast8_t pass;

  1289.     uint_fast8_t ch_used;

  1290.     uint_fast8_t i,j,l;

  1291.     uint_fast16_t k;

  1292. 

  1293.     if (vr_type == 2) {

  1294.         for (j = 1; j < ch; ++j)

  1295.             do_not_decode[0] &= do_not_decode[j];  // FIXME - clobbering input

  1296.         if (do_not_decode[0])

  1297.             return 0;

  1298.         ch_used = 1;

  1299.     } else {

  1300.         ch_used = ch;

  1301.     }

  1302. 

  1303.     AV_DEBUG(" residue type 0/1/2 decode begin, ch: %d  cpc %d  \n", ch, c_p_c);

  1304. 

  1305.     for (pass = 0; pass <= vr->maxpass; ++pass) { // FIXME OPTIMIZE?

  1306.         uint_fast16_t voffset;

  1307.         uint_fast16_t partition_count;

  1308.         uint_fast16_t j_times_ptns_to_read;

  1309. 

  1310.         voffset = vr->begin;

  1311.         for (partition_count = 0; partition_count < ptns_to_read;) {  // SPEC        error

  1312.             if (!pass) {

  1313.                 uint_fast32_t inverse_class = ff_inverse[vr->classifications];

  1314.                 for (j_times_ptns_to_read = 0, j = 0; j < ch_used; ++j) {

  1315.                     if (!do_not_decode[j]) {

  1316.                         uint_fast32_t temp = get_vlc2(gb, vc->codebooks[vr->classbook].vlc.table,

  1317.                         vc->codebooks[vr->classbook].nb_bits, 3);

  1318. 

  1319.                         AV_DEBUG("Classword: %d \n", temp);

  1320. 

  1321.                         assert(vr->classifications > 1 && temp <= 65536); //needed for inverse[]

  1322.                         for (i = 0; i < c_p_c; ++i) {

  1323.                             uint_fast32_t temp2;

  1324. 

  1325.                             temp2 = (((uint_fast64_t)temp) * inverse_class) >> 32;

  1326.                             if (partition_count + c_p_c - 1 - i < ptns_to_read)

  1327.                                 classifs[j_times_ptns_to_read + partition_count + c_p_c - 1 - i] = temp - temp2 * vr->classifications;

  1328.                             temp = temp2;

  1329.                         }

  1330.                     }

  1331.                     j_times_ptns_to_read += ptns_to_read;

  1332.                 }

  1333.             }

  1334.             for (i = 0; (i < c_p_c) && (partition_count < ptns_to_read); ++i) {

  1335.                 for (j_times_ptns_to_read = 0, j = 0; j < ch_used; ++j) {

  1336.                     uint_fast16_t voffs;

  1337. 

  1338.                     if (!do_not_decode[j]) {

  1339.                         uint_fast8_t vqclass = classifs[j_times_ptns_to_read+partition_count];

  1340.                         int_fast16_t vqbook = vr->books[vqclass][pass];

  1341. 

  1342.                         if (vqbook >= 0 && vc->codebooks[vqbook].codevectors) {

  1343.                             uint_fast16_t coffs;

  1344.                             unsigned dim =  vc->codebooks[vqbook].dimensions; // not uint_fast8_t: 64bit is slower here on amd64

  1345.                             uint_fast16_t step = dim == 1 ? vr->partition_size

  1346.                                                           : FASTDIV(vr->partition_size, dim);

  1347.                             vorbis_codebook codebook = vc->codebooks[vqbook];

  1348. 

  1349.                             if (vr_type == 0) {

  1350. 

  1351.                                 voffs = voffset+j*vlen;

  1352.                                 for (k = 0; k < step; ++k) {

  1353.                                     coffs = get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * dim;

  1354.                                     for (l = 0; l < dim; ++l)

  1355.                                         vec[voffs + k + l * step] += codebook.codevectors[coffs + l];  // FPMATH

  1356.                                 }

  1357.                             } else if (vr_type == 1) {

  1358.                                 voffs = voffset + j * vlen;

  1359.                                 for (k = 0; k < step; ++k) {

  1360.                                     coffs = get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * dim;

  1361.                                     for (l = 0; l < dim; ++l, ++voffs) {

  1362.                                         vec[voffs]+=codebook.codevectors[coffs+l];  // FPMATH

  1363. 

  1364.                                         AV_DEBUG(" pass %d offs: %d curr: %f change: %f cv offs.: %d  \n", pass, voffs, vec[voffs], codebook.codevectors[coffs+l], coffs);

  1365.                                     }

  1366.                                 }

  1367.                             } else if (vr_type == 2 && ch == 2 && (voffset & 1) == 0 && (dim & 1) == 0) { // most frequent case optimized

  1368.                                 voffs = voffset >> 1;

  1369. 

  1370.                                 if (dim == 2) {

  1371.                                     for (k = 0; k < step; ++k) {

  1372.                                         coffs = get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * 2;

  1373.                                         vec[voffs + k       ] += codebook.codevectors[coffs    ];  // FPMATH

  1374.                                         vec[voffs + k + vlen] += codebook.codevectors[coffs + 1];  // FPMATH

  1375.                                     }

  1376.                                 } else if (dim == 4) {

  1377.                                     for (k = 0; k < step; ++k, voffs += 2) {

  1378.                                         coffs = get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * 4;

  1379.                                         vec[voffs           ] += codebook.codevectors[coffs    ];  // FPMATH

  1380.                                         vec[voffs + 1       ] += codebook.codevectors[coffs + 2];  // FPMATH

  1381.                                         vec[voffs + vlen    ] += codebook.codevectors[coffs + 1];  // FPMATH

  1382.                                         vec[voffs + vlen + 1] += codebook.codevectors[coffs + 3];  // FPMATH

  1383.                                     }

  1384.                                 } else

  1385.                                 for (k = 0; k < step; ++k) {

  1386.                                     coffs = get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * dim;

  1387.                                     for (l = 0; l < dim; l += 2, voffs++) {

  1388.                                         vec[voffs       ] += codebook.codevectors[coffs + l    ];  // FPMATH

  1389.                                         vec[voffs + vlen] += codebook.codevectors[coffs + l + 1];  // FPMATH

  1390. 

  1391.                                         AV_DEBUG(" pass %d offs: %d curr: %f change: %f cv offs.: %d+%d  \n", pass, voffset / ch + (voffs % ch) * vlen, vec[voffset / ch + (voffs % ch) * vlen], codebook.codevectors[coffs + l], coffs, l);

  1392.                                     }

  1393.                                 }

  1394. 

  1395.                             } else if (vr_type == 2) {

  1396.                                 voffs = voffset;

  1397. 

  1398.                                 for (k = 0; k < step; ++k) {

  1399.                                     coffs = get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * dim;

  1400.                                     for (l = 0; l < dim; ++l, ++voffs) {

  1401.                                         vec[voffs / ch + (voffs % ch) * vlen] += codebook.codevectors[coffs + l];  // FPMATH FIXME use if and counter instead of / and %

  1402. 

  1403.                                         AV_DEBUG(" pass %d offs: %d curr: %f change: %f cv offs.: %d+%d  \n", pass, voffset / ch + (voffs % ch) * vlen, vec[voffset / ch + (voffs % ch) * vlen], codebook.codevectors[coffs + l], coffs, l);

  1404.                                     }

  1405.                                 }

  1406.                             }

  1407.                         }

  1408.                     }

  1409.                     j_times_ptns_to_read += ptns_to_read;

  1410.                 }

  1411.                 ++partition_count;

  1412.                 voffset += vr->partition_size;

  1413.             }

  1414.         }

  1415.     }

  1416.     return 0;

  1417. }

  1418. 

  1419. static inline int vorbis_residue_decode(vorbis_context *vc, vorbis_residue *vr,

  1420.                                         uint_fast8_t ch,

  1421.                                         uint_fast8_t *do_not_decode,

  1422.                                         float *vec, uint_fast16_t vlen)

  1423. {

  1424.     if (vr->type == 2)

  1425.         return vorbis_residue_decode_internal(vc, vr, ch, do_not_decode, vec, vlen, 2);

  1426.     else if (vr->type == 1)

  1427.         return vorbis_residue_decode_internal(vc, vr, ch, do_not_decode, vec, vlen, 1);

  1428.     else if (vr->type == 0)

  1429.         return vorbis_residue_decode_internal(vc, vr, ch, do_not_decode, vec, vlen, 0);

  1430.     else {

  1431.         av_log(vc->avccontext, AV_LOG_ERROR, " Invalid residue type while residue decode?! \n");

  1432.         return -1;

  1433.     }

  1434. }

  1435. 

  1436. void vorbis_inverse_coupling(float *mag, float *ang, int blocksize)

  1437. {

  1438.     int i;

  1439.     for (i = 0;  i < blocksize;  i++) {

  1440.         if (mag[i] > 0.0) {

  1441.             if (ang[i] > 0.0) {

  1442.                 ang[i] = mag[i] - ang[i];

  1443.             } else {

  1444.                 float temp = ang[i];

  1445.                 ang[i]     = mag[i];

  1446.                 mag[i]    += temp;

  1447.             }

  1448.         } else {

  1449.             if (ang[i] > 0.0) {

  1450.                 ang[i] += mag[i];

  1451.             } else {

  1452.                 float temp = ang[i];

  1453.                 ang[i]     = mag[i];

  1454.                 mag[i]    -= temp;

  1455.             }

  1456.         }

  1457.     }

  1458. }

  1459. 

  1460. static void copy_normalize(float *dst, float *src, int len, int exp_bias,

  1461.                            float add_bias)

  1462. {

  1463.     int i;

  1464.     if (exp_bias) {

  1465.         memcpy(dst, src, len * sizeof(float));

  1466.     } else {

  1467.         for (i = 0; i < len; i++)

  1468.             dst[i] = src[i] + add_bias;

  1469.     }

  1470. }

  1471. 

  1472. // Decode the audio packet using the functions above

  1473. 

  1474. static int vorbis_parse_audio_packet(vorbis_context *vc)

  1475. {

  1476.     GetBitContext *gb = &vc->gb;

  1477. 

  1478.     uint_fast8_t previous_window = vc->previous_window;

  1479.     uint_fast8_t mode_number;

  1480.     uint_fast8_t blockflag;

  1481.     uint_fast16_t blocksize;

  1482.     int_fast32_t i,j;

  1483.     uint_fast8_t no_residue[vc->audio_channels];

  1484.     uint_fast8_t do_not_decode[vc->audio_channels];

  1485.     vorbis_mapping *mapping;

  1486.     float *ch_res_ptr   = vc->channel_residues;

  1487.     float *ch_floor_ptr = vc->channel_floors;

  1488.     uint_fast8_t res_chan[vc->audio_channels];

  1489.     uint_fast8_t res_num = 0;

  1490.     int_fast16_t retlen  = 0;

  1491.     float fadd_bias = vc->add_bias;

  1492. 

  1493.     if (get_bits1(gb)) {

  1494.         av_log(vc->avccontext, AV_LOG_ERROR, "Not a Vorbis I audio packet.\n");

  1495.         return -1; // packet type not audio

  1496.     }

  1497. 

  1498.     if (vc->mode_count == 1) {

  1499.         mode_number = 0;

  1500.     } else {

  1501.         mode_number = get_bits(gb, ilog(vc->mode_count-1));

  1502.     }

  1503.     if (mode_number >= vc->mode_count) {

  1504.         av_log(vc->avccontext, AV_LOG_ERROR, "mode number %d out of range.\n", mode_number);

  1505.         return -1;

  1506.     }

  1507.     vc->mode_number = mode_number;

  1508.     mapping = &vc->mappings[vc->modes[mode_number].mapping];

  1509. 

  1510.     AV_DEBUG(" Mode number: %d , mapping: %d , blocktype %d \n", mode_number, vc->modes[mode_number].mapping, vc->modes[mode_number].blockflag);

  1511. 

  1512.     blockflag = vc->modes[mode_number].blockflag;

  1513.     blocksize = vc->blocksize[blockflag];

  1514.     if (blockflag)

  1515.         skip_bits(gb, 2); // previous_window, next_window

  1516. 

  1517.     memset(ch_res_ptr,   0, sizeof(float) * vc->audio_channels * blocksize / 2); //FIXME can this be removed ?

  1518.     memset(ch_floor_ptr, 0, sizeof(float) * vc->audio_channels * blocksize / 2); //FIXME can this be removed ?

  1519. 

  1520. // Decode floor

  1521. 

  1522.     for (i = 0; i < vc->audio_channels; ++i) {

  1523.         vorbis_floor *floor;

  1524.         if (mapping->submaps > 1) {

  1525.             floor = &vc->floors[mapping->submap_floor[mapping->mux[i]]];

  1526.         } else {

  1527.             floor = &vc->floors[mapping->submap_floor[0]];

  1528.         }

  1529. 

  1530.         no_residue[i] = floor->decode(vc, &floor->data, ch_floor_ptr);

  1531.         ch_floor_ptr += blocksize / 2;

  1532.     }

  1533. 

  1534. // Nonzero vector propagate

  1535. 

  1536.     for (i = mapping->coupling_steps - 1; i >= 0; --i) {

  1537.         if (!(no_residue[mapping->magnitude[i]] & no_residue[mapping->angle[i]])) {

  1538.             no_residue[mapping->magnitude[i]] = 0;

  1539.             no_residue[mapping->angle[i]]     = 0;

  1540.         }

  1541.     }

  1542. 

  1543. // Decode residue

  1544. 

  1545.     for (i = 0; i < mapping->submaps; ++i) {

  1546.         vorbis_residue *residue;

  1547.         uint_fast8_t ch = 0;

  1548. 

  1549.         for (j = 0; j < vc->audio_channels; ++j) {

  1550.             if ((mapping->submaps == 1) || (i == mapping->mux[j])) {

  1551.                 res_chan[j] = res_num;

  1552.                 if (no_residue[j]) {

  1553.                     do_not_decode[ch] = 1;

  1554.                 } else {

  1555.                     do_not_decode[ch] = 0;

  1556.                 }

  1557.                 ++ch;

  1558.                 ++res_num;

  1559.             }

  1560.         }

  1561.         residue = &vc->residues[mapping->submap_residue[i]];

  1562.         vorbis_residue_decode(vc, residue, ch, do_not_decode, ch_res_ptr, blocksize/2);

  1563. 

  1564.         ch_res_ptr += ch * blocksize / 2;

  1565.     }

  1566. 

  1567. // Inverse coupling

  1568. 

  1569.     for (i = mapping->coupling_steps - 1; i >= 0; --i) { //warning: i has to be signed

  1570.         float *mag, *ang;

  1571. 

  1572.         mag = vc->channel_residues+res_chan[mapping->magnitude[i]] * blocksize / 2;

  1573.         ang = vc->channel_residues+res_chan[mapping->angle[i]]     * blocksize / 2;

  1574.         vc->dsp.vorbis_inverse_coupling(mag, ang, blocksize / 2);

  1575.     }

  1576. 

  1577. // Dotproduct, MDCT

  1578. 

  1579.     for (j = vc->audio_channels-1;j >= 0; j--) {

  1580.         ch_floor_ptr = vc->channel_floors   + j           * blocksize / 2;

  1581.         ch_res_ptr   = vc->channel_residues + res_chan[j] * blocksize / 2;

  1582.         vc->dsp.vector_fmul(ch_floor_ptr, ch_res_ptr, blocksize / 2);

  1583.         ff_imdct_half(&vc->mdct[blockflag], ch_res_ptr, ch_floor_ptr);

  1584.     }

  1585. 

  1586. // Overlap/add, save data for next overlapping  FPMATH

  1587. 

  1588.     retlen = (blocksize + vc->blocksize[previous_window]) / 4;

  1589.     for (j = 0; j < vc->audio_channels; j++) {

  1590.         uint_fast16_t bs0 = vc->blocksize[0];

  1591.         uint_fast16_t bs1 = vc->blocksize[1];

  1592.         float *residue    = vc->channel_residues + res_chan[j] * blocksize / 2;

  1593.         float *saved      = vc->saved + j * bs1 / 4;

  1594.         float *ret        = vc->channel_floors + j * retlen;

  1595.         float *buf        = residue;

  1596.         const float *win  = vc->win[blockflag & previous_window];

  1597. 

  1598.         if (blockflag == previous_window) {

  1599.             vc->dsp.vector_fmul_window(ret, saved, buf, win, fadd_bias, blocksize / 4);

  1600.         } else if (blockflag > previous_window) {

  1601.             vc->dsp.vector_fmul_window(ret, saved, buf, win, fadd_bias, bs0 / 4);

  1602.             copy_normalize(ret+bs0/2, buf+bs0/4, (bs1-bs0)/4, vc->exp_bias, fadd_bias);

  1603.         } else {

  1604.             copy_normalize(ret, saved, (bs1 - bs0) / 4, vc->exp_bias, fadd_bias);

  1605.             vc->dsp.vector_fmul_window(ret + (bs1 - bs0) / 4, saved + (bs1 - bs0) / 4, buf, win, fadd_bias, bs0 / 4);

  1606.         }

  1607.         memcpy(saved, buf + blocksize / 4, blocksize / 4 * sizeof(float));

  1608.     }

  1609. 

  1610.     vc->previous_window = blockflag;

  1611.     return retlen;

  1612. }

  1613. 

  1614. // Return the decoded audio packet through the standard api

  1615. 

  1616. static int vorbis_decode_frame(AVCodecContext *avccontext,

  1617.                                void *data, int *data_size,

  1618.                                AVPacket *avpkt)

  1619. {

  1620.     const uint8_t *buf = avpkt->data;

  1621.     int buf_size       = avpkt->size;

  1622.     vorbis_context *vc = avccontext->priv_data ;

  1623.     GetBitContext *gb = &(vc->gb);

  1624.     const float *channel_ptrs[vc->audio_channels];

  1625.     int i;

  1626. 

  1627.     int_fast16_t len;

  1628. 

  1629.     if (!buf_size)

  1630.         return 0;

  1631. 

  1632.     AV_DEBUG("packet length %d \n", buf_size);

  1633. 

  1634.     init_get_bits(gb, buf, buf_size*8);

  1635. 

  1636.     len = vorbis_parse_audio_packet(vc);

  1637. 

  1638.     if (len <= 0) {

  1639.         *data_size = 0;

  1640.         return buf_size;

  1641.     }

  1642. 

  1643.     if (!vc->first_frame) {

  1644.         vc->first_frame = 1;

  1645.         *data_size = 0;

  1646.         return buf_size ;

  1647.     }

  1648. 

  1649.     AV_DEBUG("parsed %d bytes %d bits, returned %d samples (*ch*bits) \n", get_bits_count(gb)/8, get_bits_count(gb)%8, len);

  1650. 

  1651.     if (vc->audio_channels > 6) {

  1652.         for (i = 0; i < vc->audio_channels; i++)

  1653.             channel_ptrs[i] = vc->channel_floors + i * len;

  1654.     } else {

  1655.         for (i = 0; i < vc->audio_channels; i++)

  1656.             channel_ptrs[i] = vc->channel_floors +

  1657.                               len * ff_vorbis_channel_layout_offsets[vc->audio_channels - 1][i];

  1658.     }

  1659. 

  1660.     vc->dsp.float_to_int16_interleave(data, channel_ptrs, len, vc->audio_channels);

  1661.     *data_size = len * 2 * vc->audio_channels;

  1662. 

  1663.     return buf_size ;

  1664. }

  1665. 

  1666. // Close decoder

  1667. 

  1668. static av_cold int vorbis_decode_close(AVCodecContext *avccontext)

  1669. {

  1670.     vorbis_context *vc = avccontext->priv_data;

  1671. 

  1672.     vorbis_free(vc);

  1673. 

  1674.     return 0 ;

  1675. }

  1676. 

  1677. AVCodec vorbis_decoder = {

  1678.     "vorbis",

  1679.     CODEC_TYPE_AUDIO,

  1680.     CODEC_ID_VORBIS,

  1681.     sizeof(vorbis_context),

  1682.     vorbis_decode_init,

  1683.     NULL,

  1684.     vorbis_decode_close,

  1685.     vorbis_decode_frame,

  1686.     .long_name = NULL_IF_CONFIG_SMALL("Vorbis"),

  1687.     .channel_layouts = ff_vorbis_channel_layouts,

  1688. };