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FFmpeg/libavcodec/vorbis_dec.c

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  1. /**

  2.  * @file

  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. #include "fft.h"

  34. 

  35. #include "vorbis.h"

  36. #include "xiph.h"

  37. 

  38. #define V_NB_BITS 8

  39. #define V_NB_BITS2 11

  40. #define V_MAX_VLCS (1 << 16)

  41. #define V_MAX_PARTITIONS (1 << 20)

  42. 

  43. #ifndef V_DEBUG

  44. #define AV_DEBUG(...)

  45. #endif

  46. 

  47. #undef NDEBUG

  48. #include <assert.h>

  49. 

  50. typedef struct {

  51.     uint_fast8_t dimensions;

  52.     uint_fast8_t lookup_type;

  53.     uint_fast8_t maxdepth;

  54.     VLC vlc;

  55.     float *codevectors;

  56.     unsigned int nb_bits;

  57. } vorbis_codebook;

  58. 

  59. typedef union  vorbis_floor_u  vorbis_floor_data;

  60. typedef struct vorbis_floor0_s vorbis_floor0;

  61. typedef struct vorbis_floor1_s vorbis_floor1;

  62. struct vorbis_context_s;

  63. typedef

  64. uint_fast8_t (* vorbis_floor_decode_func)

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

  66. typedef struct {

  67.     uint_fast8_t floor_type;

  68.     vorbis_floor_decode_func decode;

  69.     union vorbis_floor_u {

  70.         struct vorbis_floor0_s {

  71.             uint_fast8_t  order;

  72.             uint_fast16_t rate;

  73.             uint_fast16_t bark_map_size;

  74.             int_fast32_t *map[2];

  75.             uint_fast32_t map_size[2];

  76.             uint_fast8_t  amplitude_bits;

  77.             uint_fast8_t  amplitude_offset;

  78.             uint_fast8_t  num_books;

  79.             uint_fast8_t *book_list;

  80.             float        *lsp;

  81.         } t0;

  82.         struct vorbis_floor1_s {

  83.             uint_fast8_t partitions;

  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 const char idx_err_str[] = "Index value %d out of range (0 - %d) for %s at %s:%i\n";

  164. #define VALIDATE_INDEX(idx, limit) \

  165.     if (idx >= limit) {\

  166.         av_log(vc->avccontext, AV_LOG_ERROR,\

  167.                idx_err_str,\

  168.                (int)(idx), (int)(limit - 1), #idx, __FILE__, __LINE__);\

  169.         return -1;\

  170.     }

  171. #define GET_VALIDATED_INDEX(idx, bits, limit) \

  172.     {\

  173.         idx = get_bits(gb, bits);\

  174.         VALIDATE_INDEX(idx, limit)\

  175.     }

  176. 

  177. static float vorbisfloat2float(uint_fast32_t val)

  178. {

  179.     double mant = val & 0x1fffff;

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

  181.     if (val & 0x80000000)

  182.         mant = -mant;

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

  184. }

  185. 

  186. 

  187. // Free all allocated memory -----------------------------------------

  188. 

  189. static void vorbis_free(vorbis_context *vc)

  190. {

  191.     int_fast16_t i;

  192. 

  193.     av_freep(&vc->channel_residues);

  194.     av_freep(&vc->channel_floors);

  195.     av_freep(&vc->saved);

  196. 

  197.     av_freep(&vc->residues);

  198.     av_freep(&vc->modes);

  199. 

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

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

  202. 

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

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

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

  206.     }

  207.     av_freep(&vc->codebooks);

  208. 

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

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

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

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

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

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

  215.         } else {

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

  217.         }

  218.     }

  219.     av_freep(&vc->floors);

  220. 

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

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

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

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

  225.     }

  226.     av_freep(&vc->mappings);

  227. }

  228. 

  229. // Parse setup header -------------------------------------------------

  230. 

  231. // Process codebooks part

  232. 

  233. static int vorbis_parse_setup_hdr_codebooks(vorbis_context *vc)

  234. {

  235.     uint_fast16_t cb;

  236.     uint8_t  *tmp_vlc_bits;

  237.     uint32_t *tmp_vlc_codes;

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

  239. 

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

  241. 

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

  243. 

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

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

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

  247. 

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

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

  250.         uint_fast8_t ordered;

  251.         uint_fast32_t t, used_entries = 0;

  252.         uint_fast32_t entries;

  253. 

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

  255. 

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

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

  258.             goto error;

  259.         }

  260. 

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

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

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

  264.             goto error;

  265.         }

  266.         entries = get_bits(gb, 24);

  267.         if (entries > V_MAX_VLCS) {

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

  269.             goto error;

  270.         }

  271. 

  272.         ordered = get_bits1(gb);

  273. 

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

  275. 

  276.         if (!ordered) {

  277.             uint_fast16_t ce;

  278.             uint_fast8_t  flag;

  279.             uint_fast8_t  sparse = get_bits1(gb);

  280. 

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

  282. 

  283.             if (sparse) {

  284.                 AV_DEBUG(" sparse \n");

  285. 

  286.                 used_entries = 0;

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

  288.                     flag = get_bits1(gb);

  289.                     if (flag) {

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

  291.                         ++used_entries;

  292.                     } else

  293.                         tmp_vlc_bits[ce] = 0;

  294.                 }

  295.             } else {

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

  297. 

  298.                 used_entries = entries;

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

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

  301.             }

  302.         } else {

  303.             uint_fast16_t current_entry = 0;

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

  305. 

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

  307. 

  308.             used_entries = entries;

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

  310.                 uint_fast16_t i, number;

  311. 

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

  313. 

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

  315. 

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

  317. 

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

  319.                     if (i < used_entries)

  320.                         tmp_vlc_bits[i] = current_length;

  321. 

  322.                 current_entry+=number;

  323.             }

  324.             if (current_entry>used_entries) {

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

  326.                 goto error;

  327.             }

  328.         }

  329. 

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

  331. 

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

  333. 

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

  335. 

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

  337.             uint_fast16_t i, j, k;

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

  339.             uint_fast16_t codebook_multiplicands[codebook_lookup_values];

  340. 

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

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

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

  344.             uint_fast8_t codebook_sequence_p = get_bits1(gb);

  345. 

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

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

  348. 

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

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

  351. 

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

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

  354.             }

  355. 

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

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

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

  359.                 uint_fast8_t dim = codebook_setup->dimensions;

  360. 

  361.                 if (tmp_vlc_bits[i]) {

  362.                     float last = 0.0;

  363.                     uint_fast32_t lookup_offset = i;

  364. 

  365. #ifdef V_DEBUG

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

  367. #endif

  368. 

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

  370.                         uint_fast32_t multiplicand_offset = lookup_offset % codebook_lookup_values;

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

  372.                         if (codebook_sequence_p)

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

  374.                         lookup_offset/=codebook_lookup_values;

  375.                     }

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

  377. 

  378. #ifdef V_DEBUG

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

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

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

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

  383. #endif

  384. 

  385.                     ++j;

  386.                 }

  387.             }

  388.             if (j != used_entries) {

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

  390.                 goto error;

  391.             }

  392.             entries = used_entries;

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

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

  395.             goto error;

  396.         }

  397. 

  398. // Initialize VLC table

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

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

  401.             goto error;

  402.         }

  403.         codebook_setup->maxdepth = 0;

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

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

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

  407. 

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

  409.             codebook_setup->nb_bits = V_NB_BITS2;

  410.         else

  411.             codebook_setup->nb_bits = V_NB_BITS;

  412. 

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

  414. 

  415.         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)) {

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

  417.             goto error;

  418.         }

  419.     }

  420. 

  421.     av_free(tmp_vlc_bits);

  422.     av_free(tmp_vlc_codes);

  423.     return 0;

  424. 

  425. // Error:

  426. error:

  427.     av_free(tmp_vlc_bits);

  428.     av_free(tmp_vlc_codes);

  429.     return -1;

  430. }

  431. 

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

  433. 

  434. static int vorbis_parse_setup_hdr_tdtransforms(vorbis_context *vc)

  435. {

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

  437.     uint_fast8_t i;

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

  439. 

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

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

  442. 

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

  444. 

  445.         if (vorbis_tdtransform) {

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

  447.             return -1;

  448.         }

  449.     }

  450.     return 0;

  451. }

  452. 

  453. // Process floors part

  454. 

  455. static uint_fast8_t vorbis_floor0_decode(vorbis_context *vc,

  456.                                          vorbis_floor_data *vfu, float *vec);

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

  458. static uint_fast8_t vorbis_floor1_decode(vorbis_context *vc,

  459.                                          vorbis_floor_data *vfu, float *vec);

  460. static int vorbis_parse_setup_hdr_floors(vorbis_context *vc)

  461. {

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

  463.     uint_fast16_t i,j,k;

  464. 

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

  466. 

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

  468. 

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

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

  471. 

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

  473. 

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

  475. 

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

  477.             int maximum_class = -1;

  478.             uint_fast8_t  rangebits;

  479.             uint_fast16_t floor1_values = 2;

  480. 

  481.             floor_setup->decode = vorbis_floor1_decode;

  482. 

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

  484. 

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

  486. 

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

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

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

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

  491. 

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

  493. 

  494.             }

  495. 

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

  497. 

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

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

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

  501. 

  502.                 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]);

  503. 

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

  505.                     GET_VALIDATED_INDEX(floor_setup->data.t1.class_masterbook[j], 8, vc->codebook_count)

  506. 

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

  508.                 }

  509. 

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

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

  512.                     if (bits != -1)

  513.                         VALIDATE_INDEX(bits, vc->codebook_count)

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

  515. 

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

  517.                 }

  518.             }

  519. 

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

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

  522. 

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

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

  525. 

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

  527. 

  528. 

  529.             rangebits = get_bits(gb, 4);

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

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

  532. 

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

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

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

  536. 

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

  538.                 }

  539.             }

  540. 

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

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

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

  544.             uint_fast8_t max_codebook_dim = 0;

  545. 

  546.             floor_setup->decode = vorbis_floor0_decode;

  547. 

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

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

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

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

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

  553.              * 2^0 - 1 == 0                             */

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

  555.               av_log(vc->avccontext, AV_LOG_ERROR,

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

  557.               return -1;

  558.             }

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

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

  561. 

  562.             /* allocate mem for booklist */

  563.             floor_setup->data.t0.book_list =

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

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

  566.                 return -1;

  567.             /* read book indexes */

  568.             {

  569.                 int idx;

  570.                 uint_fast8_t book_idx;

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

  572.                     GET_VALIDATED_INDEX(floor_setup->data.t0.book_list[idx], 8, vc->codebook_count)

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

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

  575.                 }

  576.             }

  577. 

  578.             create_map(vc, i);

  579. 

  580.             /* allocate mem for lsp coefficients */

  581.             {

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

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

  584.                 floor_setup->data.t0.lsp =

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

  586.                               * sizeof(float));

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

  588.                     return -1;

  589.             }

  590. 

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

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

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

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

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

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

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

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

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

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

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

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

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

  604.             {

  605.               int idx;

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

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

  608.                            idx+1,

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

  610.               }

  611.             }

  612. #endif

  613.         } else {

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

  615.             return -1;

  616.         }

  617.     }

  618.     return 0;

  619. }

  620. 

  621. // Process residues part

  622. 

  623. static int vorbis_parse_setup_hdr_residues(vorbis_context *vc)

  624. {

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

  626.     uint_fast8_t i, j, k;

  627. 

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

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

  630. 

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

  632. 

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

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

  635.         uint_fast8_t cascade[64];

  636.         uint_fast8_t high_bits;

  637.         uint_fast8_t low_bits;

  638. 

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

  640. 

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

  642. 

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

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

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

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

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

  648.             res_setup->end > vc->avccontext->channels * vc->blocksize[1] / (res_setup->type == 2 ? 1 : 2) ||

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

  650.             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);

  651.             return -1;

  652.         }

  653. 

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

  655.         GET_VALIDATED_INDEX(res_setup->classbook, 8, vc->codebook_count)

  656. 

  657.         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,

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

  659. 

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

  661.             high_bits = 0;

  662.             low_bits  = get_bits(gb, 3);

  663.             if (get_bits1(gb))

  664.                 high_bits = get_bits(gb, 5);

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

  666. 

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

  668.         }

  669. 

  670.         res_setup->maxpass = 0;

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

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

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

  674.                     GET_VALIDATED_INDEX(res_setup->books[j][k], 8, vc->codebook_count)

  675. 

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

  677. 

  678.                     if (k>res_setup->maxpass)

  679.                         res_setup->maxpass = k;

  680.                 } else {

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

  682.                 }

  683.             }

  684.         }

  685.     }

  686.     return 0;

  687. }

  688. 

  689. // Process mappings part

  690. 

  691. static int vorbis_parse_setup_hdr_mappings(vorbis_context *vc)

  692. {

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

  694.     uint_fast8_t i, j;

  695. 

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

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

  698. 

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

  700. 

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

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

  703. 

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

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

  706.             return -1;

  707.         }

  708.         if (get_bits1(gb)) {

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

  710.         } else {

  711.             mapping_setup->submaps = 1;

  712.         }

  713. 

  714.         if (get_bits1(gb)) {

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

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

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

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

  719.                 GET_VALIDATED_INDEX(mapping_setup->magnitude[j], ilog(vc->audio_channels - 1), vc->audio_channels)

  720.                 GET_VALIDATED_INDEX(mapping_setup->angle[j],     ilog(vc->audio_channels - 1), vc->audio_channels)

  721.             }

  722.         } else {

  723.             mapping_setup->coupling_steps = 0;

  724.         }

  725. 

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

  727. 

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

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

  730.             return -1; // following spec.

  731.         }

  732. 

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

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

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

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

  737.         }

  738. 

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

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

  741.             GET_VALIDATED_INDEX(mapping_setup->submap_floor[j],   8, vc->floor_count)

  742.             GET_VALIDATED_INDEX(mapping_setup->submap_residue[j], 8, vc->residue_count)

  743. 

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

  745.         }

  746.     }

  747.     return 0;

  748. }

  749. 

  750. // Process modes part

  751. 

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

  753. {

  754.     vorbis_floor *floors = vc->floors;

  755.     vorbis_floor0 *vf;

  756.     int idx;

  757.     int_fast8_t blockflag;

  758.     int_fast32_t *map;

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

  760. 

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

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

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

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

  765. 

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

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

  768. 

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

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

  771.                              ((vf->bark_map_size) /

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

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

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

  775.         }

  776.         map[n] = -1;

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

  778.     }

  779. 

  780. #   ifdef V_DEBUG

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

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

  783.                  idx, map[idx]);

  784.     }

  785. #   endif

  786. }

  787. 

  788. static int vorbis_parse_setup_hdr_modes(vorbis_context *vc)

  789. {

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

  791.     uint_fast8_t i;

  792. 

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

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

  795. 

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

  797. 

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

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

  800. 

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

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

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

  804.         GET_VALIDATED_INDEX(mode_setup->mapping, 8, vc->mapping_count);

  805. 

  806.         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);

  807.     }

  808.     return 0;

  809. }

  810. 

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

  812. 

  813. static int vorbis_parse_setup_hdr(vorbis_context *vc)

  814. {

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

  816. 

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

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

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

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

  821.         return -1;

  822.     }

  823. 

  824.     if (vorbis_parse_setup_hdr_codebooks(vc)) {

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

  826.         return -2;

  827.     }

  828.     if (vorbis_parse_setup_hdr_tdtransforms(vc)) {

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

  830.         return -3;

  831.     }

  832.     if (vorbis_parse_setup_hdr_floors(vc)) {

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

  834.         return -4;

  835.     }

  836.     if (vorbis_parse_setup_hdr_residues(vc)) {

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

  838.         return -5;

  839.     }

  840.     if (vorbis_parse_setup_hdr_mappings(vc)) {

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

  842.         return -6;

  843.     }

  844.     if (vorbis_parse_setup_hdr_modes(vc)) {

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

  846.         return -7;

  847.     }

  848.     if (!get_bits1(gb)) {

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

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

  851.     }

  852. 

  853.     return 0;

  854. }

  855. 

  856. // Process the identification header

  857. 

  858. static int vorbis_parse_id_hdr(vorbis_context *vc)

  859. {

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

  861.     uint_fast8_t bl0, bl1;

  862. 

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

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

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

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

  867.         return -1;

  868.     }

  869. 

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

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

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

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

  874.         return -1;

  875.     }

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

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

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

  879.         return -1;

  880.     }

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

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

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

  884.     bl0 = get_bits(gb, 4);

  885.     bl1 = get_bits(gb, 4);

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

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

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

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

  890.         return -3;

  891.     }

  892.     // output format int16

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

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

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

  896.         return -4;

  897.     }

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

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

  900. 

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

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

  903.         return -2;

  904.     }

  905. 

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

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

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

  909.     vc->previous_window  = 0;

  910. 

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

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

  913. 

  914.     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 ",

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

  916. 

  917. /*

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

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

  920.         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)));

  921.     }

  922. */

  923. 

  924.     return 0;

  925. }

  926. 

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

  928. 

  929. static av_cold int vorbis_decode_init(AVCodecContext *avccontext)

  930. {

  931.     vorbis_context *vc = avccontext->priv_data ;

  932.     uint8_t *headers   = avccontext->extradata;

  933.     int headers_len    = avccontext->extradata_size;

  934.     uint8_t *header_start[3];

  935.     int header_len[3];

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

  937.     int hdr_type;

  938. 

  939.     vc->avccontext = avccontext;

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

  941. 

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

  943.         vc->add_bias = 385;

  944.         vc->exp_bias = 0;

  945.     } else {

  946.         vc->add_bias = 0;

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

  948.     }

  949. 

  950.     if (!headers_len) {

  951.         av_log(avccontext, AV_LOG_ERROR, "Extradata missing.\n");

  952.         return -1;

  953.     }

  954. 

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

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

  957.         return -1;

  958.     }

  959. 

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

  961.     hdr_type = get_bits(gb, 8);

  962.     if (hdr_type != 1) {

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

  964.         return -1;

  965.     }

  966.     if (vorbis_parse_id_hdr(vc)) {

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

  968.         vorbis_free(vc);

  969.         return -1;

  970.     }

  971. 

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

  973.     hdr_type = get_bits(gb, 8);

  974.     if (hdr_type != 5) {

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

  976.         vorbis_free(vc);

  977.         return -1;

  978.     }

  979.     if (vorbis_parse_setup_hdr(vc)) {

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

  981.         vorbis_free(vc);

  982.         return -1;

  983.     }

  984. 

  985.     if (vc->audio_channels > 8)

  986.         avccontext->channel_layout = 0;

  987.     else

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

  989. 

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

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

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

  993.     avccontext->sample_fmt  = SAMPLE_FMT_S16;

  994. 

  995.     return 0 ;

  996. }

  997. 

  998. // Decode audiopackets -------------------------------------------------

  999. 

  1000. // Read and decode floor

  1001. 

  1002. static uint_fast8_t vorbis_floor0_decode(vorbis_context *vc,

  1003.                                          vorbis_floor_data *vfu, float *vec)

  1004. {

  1005.     vorbis_floor0 *vf = &vfu->t0;

  1006.     float *lsp = vf->lsp;

  1007.     uint_fast32_t amplitude;

  1008.     uint_fast32_t book_idx;

  1009.     uint_fast8_t blockflag = vc->modes[vc->mode_number].blockflag;

  1010. 

  1011.     amplitude = get_bits(&vc->gb, vf->amplitude_bits);

  1012.     if (amplitude > 0) {

  1013.         float last = 0;

  1014.         uint_fast16_t lsp_len = 0;

  1015.         uint_fast16_t idx;

  1016.         vorbis_codebook codebook;

  1017. 

  1018.         book_idx = get_bits(&vc->gb, ilog(vf->num_books));

  1019.         if (book_idx >= vf->num_books) {

  1020.             av_log(vc->avccontext, AV_LOG_ERROR,

  1021.                     "floor0 dec: booknumber too high!\n");

  1022.             book_idx =  0;

  1023.             //FIXME: look above

  1024.         }

  1025.         AV_DEBUG("floor0 dec: booknumber: %u\n", book_idx);

  1026.         codebook = vc->codebooks[vf->book_list[book_idx]];

  1027. 

  1028.         while (lsp_len<vf->order) {

  1029.             int vec_off;

  1030. 

  1031.             AV_DEBUG("floor0 dec: book dimension: %d\n", codebook.dimensions);

  1032.             AV_DEBUG("floor0 dec: maximum depth: %d\n", codebook.maxdepth);

  1033.             /* read temp vector */

  1034.             vec_off = get_vlc2(&vc->gb, codebook.vlc.table,

  1035.                                codebook.nb_bits, codebook.maxdepth)

  1036.                       * codebook.dimensions;

  1037.             AV_DEBUG("floor0 dec: vector offset: %d\n", vec_off);

  1038.             /* copy each vector component and add last to it */

  1039.             for (idx = 0; idx < codebook.dimensions; ++idx)

  1040.                 lsp[lsp_len+idx] = codebook.codevectors[vec_off+idx] + last;

  1041.             last = lsp[lsp_len+idx-1]; /* set last to last vector component */

  1042. 

  1043.             lsp_len += codebook.dimensions;

  1044.         }

  1045. #ifdef V_DEBUG

  1046.         /* DEBUG: output lsp coeffs */

  1047.         {

  1048.             int idx;

  1049.             for (idx = 0; idx < lsp_len; ++idx)

  1050.                 AV_DEBUG("floor0 dec: coeff at %d is %f\n", idx, lsp[idx]);

  1051.         }

  1052. #endif

  1053. 

  1054.         /* synthesize floor output vector */

  1055.         {

  1056.             int i;

  1057.             int order = vf->order;

  1058.             float wstep = M_PI / vf->bark_map_size;

  1059. 

  1060.             for (i = 0; i < order; i++)

  1061.                 lsp[i] = 2.0f * cos(lsp[i]);

  1062. 

  1063.             AV_DEBUG("floor0 synth: map_size = %d; m = %d; wstep = %f\n",

  1064.                      vf->map_size, order, wstep);

  1065. 

  1066.             i = 0;

  1067.             while (i < vf->map_size[blockflag]) {

  1068.                 int j, iter_cond = vf->map[blockflag][i];

  1069.                 float p = 0.5f;

  1070.                 float q = 0.5f;

  1071.                 float two_cos_w = 2.0f * cos(wstep * iter_cond); // needed all times

  1072. 

  1073.                 /* similar part for the q and p products */

  1074.                 for (j = 0; j + 1 < order; j += 2) {

  1075.                     q *= lsp[j]     - two_cos_w;

  1076.                     p *= lsp[j + 1] - two_cos_w;

  1077.                 }

  1078.                 if (j == order) { // even order

  1079.                     p *= p * (2.0f - two_cos_w);

  1080.                     q *= q * (2.0f + two_cos_w);

  1081.                 } else { // odd order

  1082.                     q *= two_cos_w-lsp[j]; // one more time for q

  1083. 

  1084.                     /* final step and square */

  1085.                     p *= p * (4.f - two_cos_w * two_cos_w);

  1086.                     q *= q;

  1087.                 }

  1088. 

  1089.                 /* calculate linear floor value */

  1090.                 {

  1091.                     q = exp((((amplitude*vf->amplitude_offset) /

  1092.                               (((1 << vf->amplitude_bits) - 1) * sqrt(p + q)))

  1093.                              - vf->amplitude_offset) * .11512925f);

  1094.                 }

  1095. 

  1096.                 /* fill vector */

  1097.                 do {

  1098.                     vec[i] = q; ++i;

  1099.                 } while (vf->map[blockflag][i] == iter_cond);

  1100.             }

  1101.         }

  1102.     } else {

  1103.         /* this channel is unused */

  1104.         return 1;

  1105.     }

  1106. 

  1107.     AV_DEBUG(" Floor0 decoded\n");

  1108. 

  1109.     return 0;

  1110. }

  1111. 

  1112. static uint_fast8_t vorbis_floor1_decode(vorbis_context *vc,

  1113.                                          vorbis_floor_data *vfu, float *vec)

  1114. {

  1115.     vorbis_floor1 *vf = &vfu->t1;

  1116.     GetBitContext *gb = &vc->gb;

  1117.     uint_fast16_t range_v[4] = { 256, 128, 86, 64 };

  1118.     uint_fast16_t range = range_v[vf->multiplier-1];

  1119.     uint_fast16_t floor1_Y[vf->x_list_dim];

  1120.     uint_fast16_t floor1_Y_final[vf->x_list_dim];

  1121.     int floor1_flag[vf->x_list_dim];

  1122.     uint_fast8_t class_;

  1123.     uint_fast8_t cdim;

  1124.     uint_fast8_t cbits;

  1125.     uint_fast8_t csub;

  1126.     uint_fast8_t cval;

  1127.     int_fast16_t book;

  1128.     uint_fast16_t offset;

  1129.     uint_fast16_t i,j;

  1130.     /*u*/int_fast16_t adx, ady, off, predicted; // WTF ? dy/adx =  (unsigned)dy/adx ?

  1131.     int_fast16_t dy, err;

  1132. 

  1133. 

  1134.     if (!get_bits1(gb)) // silence

  1135.         return 1;

  1136. 

  1137. // Read values (or differences) for the floor's points

  1138. 

  1139.     floor1_Y[0] = get_bits(gb, ilog(range - 1));

  1140.     floor1_Y[1] = get_bits(gb, ilog(range - 1));

  1141. 

  1142.     AV_DEBUG("floor 0 Y %d floor 1 Y %d \n", floor1_Y[0], floor1_Y[1]);

  1143. 

  1144.     offset = 2;

  1145.     for (i = 0; i < vf->partitions; ++i) {

  1146.         class_ = vf->partition_class[i];

  1147.         cdim   = vf->class_dimensions[class_];

  1148.         cbits  = vf->class_subclasses[class_];

  1149.         csub = (1 << cbits) - 1;

  1150.         cval = 0;

  1151. 

  1152.         AV_DEBUG("Cbits %d \n", cbits);

  1153. 

  1154.         if (cbits) // this reads all subclasses for this partition's class

  1155.             cval = get_vlc2(gb, vc->codebooks[vf->class_masterbook[class_]].vlc.table,

  1156.                             vc->codebooks[vf->class_masterbook[class_]].nb_bits, 3);

  1157. 

  1158.         for (j = 0; j < cdim; ++j) {

  1159.             book = vf->subclass_books[class_][cval & csub];

  1160. 

  1161.             AV_DEBUG("book %d Cbits %d cval %d  bits:%d \n", book, cbits, cval, get_bits_count(gb));

  1162. 

  1163.             cval = cval >> cbits;

  1164.             if (book > -1) {

  1165.                 floor1_Y[offset+j] = get_vlc2(gb, vc->codebooks[book].vlc.table,

  1166.                 vc->codebooks[book].nb_bits, 3);

  1167.             } else {

  1168.                 floor1_Y[offset+j] = 0;

  1169.             }

  1170. 

  1171.             AV_DEBUG(" floor(%d) = %d \n", vf->list[offset+j].x, floor1_Y[offset+j]);

  1172.         }

  1173.         offset+=cdim;

  1174.     }

  1175. 

  1176. // Amplitude calculation from the differences

  1177. 

  1178.     floor1_flag[0] = 1;

  1179.     floor1_flag[1] = 1;

  1180.     floor1_Y_final[0] = floor1_Y[0];

  1181.     floor1_Y_final[1] = floor1_Y[1];

  1182. 

  1183.     for (i = 2; i < vf->x_list_dim; ++i) {

  1184.         uint_fast16_t val, highroom, lowroom, room;

  1185.         uint_fast16_t high_neigh_offs;

  1186.         uint_fast16_t low_neigh_offs;

  1187. 

  1188.         low_neigh_offs  = vf->list[i].low;

  1189.         high_neigh_offs = vf->list[i].high;

  1190.         dy  = floor1_Y_final[high_neigh_offs] - floor1_Y_final[low_neigh_offs];  // render_point begin

  1191.         adx = vf->list[high_neigh_offs].x - vf->list[low_neigh_offs].x;

  1192.         ady = FFABS(dy);

  1193.         err = ady * (vf->list[i].x - vf->list[low_neigh_offs].x);

  1194.         off = (int16_t)err / (int16_t)adx;

  1195.         if (dy < 0) {

  1196.             predicted = floor1_Y_final[low_neigh_offs] - off;

  1197.         } else {

  1198.             predicted = floor1_Y_final[low_neigh_offs] + off;

  1199.         } // render_point end

  1200. 

  1201.         val = floor1_Y[i];

  1202.         highroom = range-predicted;

  1203.         lowroom  = predicted;

  1204.         if (highroom < lowroom) {

  1205.             room = highroom * 2;

  1206.         } else {

  1207.             room = lowroom * 2;   // SPEC mispelling

  1208.         }

  1209.         if (val) {

  1210.             floor1_flag[low_neigh_offs]  = 1;

  1211.             floor1_flag[high_neigh_offs] = 1;

  1212.             floor1_flag[i]               = 1;

  1213.             if (val >= room) {

  1214.                 if (highroom > lowroom) {

  1215.                     floor1_Y_final[i] = val - lowroom + predicted;

  1216.                 } else {

  1217.                     floor1_Y_final[i] = predicted - val + highroom - 1;

  1218.                 }

  1219.             } else {

  1220.                 if (val & 1) {

  1221.                     floor1_Y_final[i] = predicted - (val + 1) / 2;

  1222.                 } else {

  1223.                     floor1_Y_final[i] = predicted + val / 2;

  1224.                 }

  1225.             }

  1226.         } else {

  1227.             floor1_flag[i]    = 0;

  1228.             floor1_Y_final[i] = predicted;

  1229.         }

  1230. 

  1231.         AV_DEBUG(" Decoded floor(%d) = %d / val %d \n", vf->list[i].x, floor1_Y_final[i], val);

  1232.     }

  1233. 

  1234. // Curve synth - connect the calculated dots and convert from dB scale FIXME optimize ?

  1235. 

  1236.     ff_vorbis_floor1_render_list(vf->list, vf->x_list_dim, floor1_Y_final, floor1_flag, vf->multiplier, vec, vf->list[1].x);

  1237. 

  1238.     AV_DEBUG(" Floor decoded\n");

  1239. 

  1240.     return 0;

  1241. }

  1242. 

  1243. // Read and decode residue

  1244. 

  1245. static av_always_inline int vorbis_residue_decode_internal(vorbis_context *vc,

  1246.                                                            vorbis_residue *vr,

  1247.                                                            uint_fast8_t ch,

  1248.                                                            uint_fast8_t *do_not_decode,

  1249.                                                            float *vec,

  1250.                                                            uint_fast16_t vlen,

  1251.                                                            int vr_type)

  1252. {

  1253.     GetBitContext *gb = &vc->gb;

  1254.     uint_fast8_t c_p_c = vc->codebooks[vr->classbook].dimensions;

  1255.     uint_fast16_t n_to_read = vr->end-vr->begin;

  1256.     uint_fast16_t ptns_to_read = n_to_read/vr->partition_size;

  1257.     uint_fast8_t classifs[ptns_to_read*vc->audio_channels];

  1258.     uint_fast8_t pass;

  1259.     uint_fast8_t ch_used;

  1260.     uint_fast8_t i,j,l;

  1261.     uint_fast16_t k;

  1262. 

  1263.     if (vr_type == 2) {

  1264.         for (j = 1; j < ch; ++j)

  1265.             do_not_decode[0] &= do_not_decode[j];  // FIXME - clobbering input

  1266.         if (do_not_decode[0])

  1267.             return 0;

  1268.         ch_used = 1;

  1269.     } else {

  1270.         ch_used = ch;

  1271.     }

  1272. 

  1273.     AV_DEBUG(" residue type 0/1/2 decode begin, ch: %d  cpc %d  \n", ch, c_p_c);

  1274. 

  1275.     for (pass = 0; pass <= vr->maxpass; ++pass) { // FIXME OPTIMIZE?

  1276.         uint_fast16_t voffset;

  1277.         uint_fast16_t partition_count;

  1278.         uint_fast16_t j_times_ptns_to_read;

  1279. 

  1280.         voffset = vr->begin;

  1281.         for (partition_count = 0; partition_count < ptns_to_read;) {  // SPEC        error

  1282.             if (!pass) {

  1283.                 uint_fast32_t inverse_class = ff_inverse[vr->classifications];

  1284.                 for (j_times_ptns_to_read = 0, j = 0; j < ch_used; ++j) {

  1285.                     if (!do_not_decode[j]) {

  1286.                         uint_fast32_t temp = get_vlc2(gb, vc->codebooks[vr->classbook].vlc.table,

  1287.                         vc->codebooks[vr->classbook].nb_bits, 3);

  1288. 

  1289.                         AV_DEBUG("Classword: %d \n", temp);

  1290. 

  1291.                         assert(vr->classifications > 1 && temp <= 65536); //needed for inverse[]

  1292.                         for (i = 0; i < c_p_c; ++i) {

  1293.                             uint_fast32_t temp2;

  1294. 

  1295.                             temp2 = (((uint_fast64_t)temp) * inverse_class) >> 32;

  1296.                             if (partition_count + c_p_c - 1 - i < ptns_to_read)

  1297.                                 classifs[j_times_ptns_to_read + partition_count + c_p_c - 1 - i] = temp - temp2 * vr->classifications;

  1298.                             temp = temp2;

  1299.                         }

  1300.                     }

  1301.                     j_times_ptns_to_read += ptns_to_read;

  1302.                 }

  1303.             }

  1304.             for (i = 0; (i < c_p_c) && (partition_count < ptns_to_read); ++i) {

  1305.                 for (j_times_ptns_to_read = 0, j = 0; j < ch_used; ++j) {

  1306.                     uint_fast16_t voffs;

  1307. 

  1308.                     if (!do_not_decode[j]) {

  1309.                         uint_fast8_t vqclass = classifs[j_times_ptns_to_read+partition_count];

  1310.                         int_fast16_t vqbook = vr->books[vqclass][pass];

  1311. 

  1312.                         if (vqbook >= 0 && vc->codebooks[vqbook].codevectors) {

  1313.                             uint_fast16_t coffs;

  1314.                             unsigned dim =  vc->codebooks[vqbook].dimensions; // not uint_fast8_t: 64bit is slower here on amd64

  1315.                             uint_fast16_t step = dim == 1 ? vr->partition_size

  1316.                                                           : FASTDIV(vr->partition_size, dim);

  1317.                             vorbis_codebook codebook = vc->codebooks[vqbook];

  1318. 

  1319.                             if (vr_type == 0) {

  1320. 

  1321.                                 voffs = voffset+j*vlen;

  1322.                                 for (k = 0; k < step; ++k) {

  1323.                                     coffs = get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * dim;

  1324.                                     for (l = 0; l < dim; ++l)

  1325.                                         vec[voffs + k + l * step] += codebook.codevectors[coffs + l];  // FPMATH

  1326.                                 }

  1327.                             } else if (vr_type == 1) {

  1328.                                 voffs = voffset + j * vlen;

  1329.                                 for (k = 0; k < step; ++k) {

  1330.                                     coffs = get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * dim;

  1331.                                     for (l = 0; l < dim; ++l, ++voffs) {

  1332.                                         vec[voffs]+=codebook.codevectors[coffs+l];  // FPMATH

  1333. 

  1334.                                         AV_DEBUG(" pass %d offs: %d curr: %f change: %f cv offs.: %d  \n", pass, voffs, vec[voffs], codebook.codevectors[coffs+l], coffs);

  1335.                                     }

  1336.                                 }

  1337.                             } else if (vr_type == 2 && ch == 2 && (voffset & 1) == 0 && (dim & 1) == 0) { // most frequent case optimized

  1338.                                 voffs = voffset >> 1;

  1339. 

  1340.                                 if (dim == 2) {

  1341.                                     for (k = 0; k < step; ++k) {

  1342.                                         coffs = get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * 2;

  1343.                                         vec[voffs + k       ] += codebook.codevectors[coffs    ];  // FPMATH

  1344.                                         vec[voffs + k + vlen] += codebook.codevectors[coffs + 1];  // FPMATH

  1345.                                     }

  1346.                                 } else if (dim == 4) {

  1347.                                     for (k = 0; k < step; ++k, voffs += 2) {

  1348.                                         coffs = get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * 4;

  1349.                                         vec[voffs           ] += codebook.codevectors[coffs    ];  // FPMATH

  1350.                                         vec[voffs + 1       ] += codebook.codevectors[coffs + 2];  // FPMATH

  1351.                                         vec[voffs + vlen    ] += codebook.codevectors[coffs + 1];  // FPMATH

  1352.                                         vec[voffs + vlen + 1] += codebook.codevectors[coffs + 3];  // FPMATH

  1353.                                     }

  1354.                                 } else

  1355.                                 for (k = 0; k < step; ++k) {

  1356.                                     coffs = get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * dim;

  1357.                                     for (l = 0; l < dim; l += 2, voffs++) {

  1358.                                         vec[voffs       ] += codebook.codevectors[coffs + l    ];  // FPMATH

  1359.                                         vec[voffs + vlen] += codebook.codevectors[coffs + l + 1];  // FPMATH

  1360. 

  1361.                                         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);

  1362.                                     }

  1363.                                 }

  1364. 

  1365.                             } else if (vr_type == 2) {

  1366.                                 voffs = voffset;

  1367. 

  1368.                                 for (k = 0; k < step; ++k) {

  1369.                                     coffs = get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * dim;

  1370.                                     for (l = 0; l < dim; ++l, ++voffs) {

  1371.                                         vec[voffs / ch + (voffs % ch) * vlen] += codebook.codevectors[coffs + l];  // FPMATH FIXME use if and counter instead of / and %

  1372. 

  1373.                                         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);

  1374.                                     }

  1375.                                 }

  1376.                             }

  1377.                         }

  1378.                     }

  1379.                     j_times_ptns_to_read += ptns_to_read;

  1380.                 }

  1381.                 ++partition_count;

  1382.                 voffset += vr->partition_size;

  1383.             }

  1384.         }

  1385.     }

  1386.     return 0;

  1387. }

  1388. 

  1389. static inline int vorbis_residue_decode(vorbis_context *vc, vorbis_residue *vr,

  1390.                                         uint_fast8_t ch,

  1391.                                         uint_fast8_t *do_not_decode,

  1392.                                         float *vec, uint_fast16_t vlen)

  1393. {

  1394.     if (vr->type == 2)

  1395.         return vorbis_residue_decode_internal(vc, vr, ch, do_not_decode, vec, vlen, 2);

  1396.     else if (vr->type == 1)

  1397.         return vorbis_residue_decode_internal(vc, vr, ch, do_not_decode, vec, vlen, 1);

  1398.     else if (vr->type == 0)

  1399.         return vorbis_residue_decode_internal(vc, vr, ch, do_not_decode, vec, vlen, 0);

  1400.     else {

  1401.         av_log(vc->avccontext, AV_LOG_ERROR, " Invalid residue type while residue decode?! \n");

  1402.         return -1;

  1403.     }

  1404. }

  1405. 

  1406. void vorbis_inverse_coupling(float *mag, float *ang, int blocksize)

  1407. {

  1408.     int i;

  1409.     for (i = 0;  i < blocksize;  i++) {

  1410.         if (mag[i] > 0.0) {

  1411.             if (ang[i] > 0.0) {

  1412.                 ang[i] = mag[i] - ang[i];

  1413.             } else {

  1414.                 float temp = ang[i];

  1415.                 ang[i]     = mag[i];

  1416.                 mag[i]    += temp;

  1417.             }

  1418.         } else {

  1419.             if (ang[i] > 0.0) {

  1420.                 ang[i] += mag[i];

  1421.             } else {

  1422.                 float temp = ang[i];

  1423.                 ang[i]     = mag[i];

  1424.                 mag[i]    -= temp;

  1425.             }

  1426.         }

  1427.     }

  1428. }

  1429. 

  1430. static void copy_normalize(float *dst, float *src, int len, int exp_bias,

  1431.                            float add_bias)

  1432. {

  1433.     int i;

  1434.     if (exp_bias) {

  1435.         memcpy(dst, src, len * sizeof(float));

  1436.     } else {

  1437.         for (i = 0; i < len; i++)

  1438.             dst[i] = src[i] + add_bias;

  1439.     }

  1440. }

  1441. 

  1442. // Decode the audio packet using the functions above

  1443. 

  1444. static int vorbis_parse_audio_packet(vorbis_context *vc)

  1445. {

  1446.     GetBitContext *gb = &vc->gb;

  1447. 

  1448.     uint_fast8_t previous_window = vc->previous_window;

  1449.     uint_fast8_t mode_number;

  1450.     uint_fast8_t blockflag;

  1451.     uint_fast16_t blocksize;

  1452.     int_fast32_t i,j;

  1453.     uint_fast8_t no_residue[vc->audio_channels];

  1454.     uint_fast8_t do_not_decode[vc->audio_channels];

  1455.     vorbis_mapping *mapping;

  1456.     float *ch_res_ptr   = vc->channel_residues;

  1457.     float *ch_floor_ptr = vc->channel_floors;

  1458.     uint_fast8_t res_chan[vc->audio_channels];

  1459.     uint_fast8_t res_num = 0;

  1460.     int_fast16_t retlen  = 0;

  1461.     float fadd_bias = vc->add_bias;

  1462. 

  1463.     if (get_bits1(gb)) {

  1464.         av_log(vc->avccontext, AV_LOG_ERROR, "Not a Vorbis I audio packet.\n");

  1465.         return -1; // packet type not audio

  1466.     }

  1467. 

  1468.     if (vc->mode_count == 1) {

  1469.         mode_number = 0;

  1470.     } else {

  1471.         GET_VALIDATED_INDEX(mode_number, ilog(vc->mode_count-1), vc->mode_count)

  1472.     }

  1473.     vc->mode_number = mode_number;

  1474.     mapping = &vc->mappings[vc->modes[mode_number].mapping];

  1475. 

  1476.     AV_DEBUG(" Mode number: %d , mapping: %d , blocktype %d \n", mode_number, vc->modes[mode_number].mapping, vc->modes[mode_number].blockflag);

  1477. 

  1478.     blockflag = vc->modes[mode_number].blockflag;

  1479.     blocksize = vc->blocksize[blockflag];

  1480.     if (blockflag)

  1481.         skip_bits(gb, 2); // previous_window, next_window

  1482. 

  1483.     memset(ch_res_ptr,   0, sizeof(float) * vc->audio_channels * blocksize / 2); //FIXME can this be removed ?

  1484.     memset(ch_floor_ptr, 0, sizeof(float) * vc->audio_channels * blocksize / 2); //FIXME can this be removed ?

  1485. 

  1486. // Decode floor

  1487. 

  1488.     for (i = 0; i < vc->audio_channels; ++i) {

  1489.         vorbis_floor *floor;

  1490.         if (mapping->submaps > 1) {

  1491.             floor = &vc->floors[mapping->submap_floor[mapping->mux[i]]];

  1492.         } else {

  1493.             floor = &vc->floors[mapping->submap_floor[0]];

  1494.         }

  1495. 

  1496.         no_residue[i] = floor->decode(vc, &floor->data, ch_floor_ptr);

  1497.         ch_floor_ptr += blocksize / 2;

  1498.     }

  1499. 

  1500. // Nonzero vector propagate

  1501. 

  1502.     for (i = mapping->coupling_steps - 1; i >= 0; --i) {

  1503.         if (!(no_residue[mapping->magnitude[i]] & no_residue[mapping->angle[i]])) {

  1504.             no_residue[mapping->magnitude[i]] = 0;

  1505.             no_residue[mapping->angle[i]]     = 0;

  1506.         }

  1507.     }

  1508. 

  1509. // Decode residue

  1510. 

  1511.     for (i = 0; i < mapping->submaps; ++i) {

  1512.         vorbis_residue *residue;

  1513.         uint_fast8_t ch = 0;

  1514. 

  1515.         for (j = 0; j < vc->audio_channels; ++j) {

  1516.             if ((mapping->submaps == 1) || (i == mapping->mux[j])) {

  1517.                 res_chan[j] = res_num;

  1518.                 if (no_residue[j]) {

  1519.                     do_not_decode[ch] = 1;

  1520.                 } else {

  1521.                     do_not_decode[ch] = 0;

  1522.                 }

  1523.                 ++ch;

  1524.                 ++res_num;

  1525.             }

  1526.         }

  1527.         residue = &vc->residues[mapping->submap_residue[i]];

  1528.         vorbis_residue_decode(vc, residue, ch, do_not_decode, ch_res_ptr, blocksize/2);

  1529. 

  1530.         ch_res_ptr += ch * blocksize / 2;

  1531.     }

  1532. 

  1533. // Inverse coupling

  1534. 

  1535.     for (i = mapping->coupling_steps - 1; i >= 0; --i) { //warning: i has to be signed

  1536.         float *mag, *ang;

  1537. 

  1538.         mag = vc->channel_residues+res_chan[mapping->magnitude[i]] * blocksize / 2;

  1539.         ang = vc->channel_residues+res_chan[mapping->angle[i]]     * blocksize / 2;

  1540.         vc->dsp.vorbis_inverse_coupling(mag, ang, blocksize / 2);

  1541.     }

  1542. 

  1543. // Dotproduct, MDCT

  1544. 

  1545.     for (j = vc->audio_channels-1;j >= 0; j--) {

  1546.         ch_floor_ptr = vc->channel_floors   + j           * blocksize / 2;

  1547.         ch_res_ptr   = vc->channel_residues + res_chan[j] * blocksize / 2;

  1548.         vc->dsp.vector_fmul(ch_floor_ptr, ch_res_ptr, blocksize / 2);

  1549.         ff_imdct_half(&vc->mdct[blockflag], ch_res_ptr, ch_floor_ptr);

  1550.     }

  1551. 

  1552. // Overlap/add, save data for next overlapping  FPMATH

  1553. 

  1554.     retlen = (blocksize + vc->blocksize[previous_window]) / 4;

  1555.     for (j = 0; j < vc->audio_channels; j++) {

  1556.         uint_fast16_t bs0 = vc->blocksize[0];

  1557.         uint_fast16_t bs1 = vc->blocksize[1];

  1558.         float *residue    = vc->channel_residues + res_chan[j] * blocksize / 2;

  1559.         float *saved      = vc->saved + j * bs1 / 4;

  1560.         float *ret        = vc->channel_floors + j * retlen;

  1561.         float *buf        = residue;

  1562.         const float *win  = vc->win[blockflag & previous_window];

  1563. 

  1564.         if (blockflag == previous_window) {

  1565.             vc->dsp.vector_fmul_window(ret, saved, buf, win, fadd_bias, blocksize / 4);

  1566.         } else if (blockflag > previous_window) {

  1567.             vc->dsp.vector_fmul_window(ret, saved, buf, win, fadd_bias, bs0 / 4);

  1568.             copy_normalize(ret+bs0/2, buf+bs0/4, (bs1-bs0)/4, vc->exp_bias, fadd_bias);

  1569.         } else {

  1570.             copy_normalize(ret, saved, (bs1 - bs0) / 4, vc->exp_bias, fadd_bias);

  1571.             vc->dsp.vector_fmul_window(ret + (bs1 - bs0) / 4, saved + (bs1 - bs0) / 4, buf, win, fadd_bias, bs0 / 4);

  1572.         }

  1573.         memcpy(saved, buf + blocksize / 4, blocksize / 4 * sizeof(float));

  1574.     }

  1575. 

  1576.     vc->previous_window = blockflag;

  1577.     return retlen;

  1578. }

  1579. 

  1580. // Return the decoded audio packet through the standard api

  1581. 

  1582. static int vorbis_decode_frame(AVCodecContext *avccontext,

  1583.                                void *data, int *data_size,

  1584.                                AVPacket *avpkt)

  1585. {

  1586.     const uint8_t *buf = avpkt->data;

  1587.     int buf_size       = avpkt->size;

  1588.     vorbis_context *vc = avccontext->priv_data ;

  1589.     GetBitContext *gb = &(vc->gb);

  1590.     const float *channel_ptrs[vc->audio_channels];

  1591.     int i;

  1592. 

  1593.     int_fast16_t len;

  1594. 

  1595.     if (!buf_size)

  1596.         return 0;

  1597. 

  1598.     AV_DEBUG("packet length %d \n", buf_size);

  1599. 

  1600.     init_get_bits(gb, buf, buf_size*8);

  1601. 

  1602.     len = vorbis_parse_audio_packet(vc);

  1603. 

  1604.     if (len <= 0) {

  1605.         *data_size = 0;

  1606.         return buf_size;

  1607.     }

  1608. 

  1609.     if (!vc->first_frame) {

  1610.         vc->first_frame = 1;

  1611.         *data_size = 0;

  1612.         return buf_size ;

  1613.     }

  1614. 

  1615.     AV_DEBUG("parsed %d bytes %d bits, returned %d samples (*ch*bits) \n", get_bits_count(gb)/8, get_bits_count(gb)%8, len);

  1616. 

  1617.     if (vc->audio_channels > 8) {

  1618.         for (i = 0; i < vc->audio_channels; i++)

  1619.             channel_ptrs[i] = vc->channel_floors + i * len;

  1620.     } else {

  1621.         for (i = 0; i < vc->audio_channels; i++)

  1622.             channel_ptrs[i] = vc->channel_floors +

  1623.                               len * ff_vorbis_channel_layout_offsets[vc->audio_channels - 1][i];

  1624.     }

  1625. 

  1626.     vc->dsp.float_to_int16_interleave(data, channel_ptrs, len, vc->audio_channels);

  1627.     *data_size = len * 2 * vc->audio_channels;

  1628. 

  1629.     return buf_size ;

  1630. }

  1631. 

  1632. // Close decoder

  1633. 

  1634. static av_cold int vorbis_decode_close(AVCodecContext *avccontext)

  1635. {

  1636.     vorbis_context *vc = avccontext->priv_data;

  1637. 

  1638.     vorbis_free(vc);

  1639. 

  1640.     return 0 ;

  1641. }

  1642. 

  1643. AVCodec vorbis_decoder = {

  1644.     "vorbis",

  1645.     AVMEDIA_TYPE_AUDIO,

  1646.     CODEC_ID_VORBIS,

  1647.     sizeof(vorbis_context),

  1648.     vorbis_decode_init,

  1649.     NULL,

  1650.     vorbis_decode_close,

  1651.     vorbis_decode_frame,

  1652.     .long_name = NULL_IF_CONFIG_SMALL("Vorbis"),

  1653.     .channel_layouts = ff_vorbis_channel_layouts,

  1654. };