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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.             uint8_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.     unsigned      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.     uint_fast16_t ptns_to_read;

  106.     uint8_t *classifs;

  107. } vorbis_residue;

  108. 

  109. typedef struct {

  110.     uint_fast8_t  submaps;

  111.     uint_fast16_t coupling_steps;

  112.     uint_fast8_t *magnitude;

  113.     uint_fast8_t *angle;

  114.     uint_fast8_t *mux;

  115.     uint_fast8_t  submap_floor[16];

  116.     uint_fast8_t  submap_residue[16];

  117. } vorbis_mapping;

  118. 

  119. typedef struct {

  120.     uint_fast8_t  blockflag;

  121.     uint_fast16_t windowtype;

  122.     uint_fast16_t transformtype;

  123.     uint_fast8_t  mapping;

  124. } vorbis_mode;

  125. 

  126. typedef struct vorbis_context_s {

  127.     AVCodecContext *avccontext;

  128.     GetBitContext gb;

  129.     DSPContext dsp;

  130. 

  131.     FFTContext mdct[2];

  132.     uint_fast8_t  first_frame;

  133.     uint_fast32_t version;

  134.     uint_fast8_t  audio_channels;

  135.     uint_fast32_t audio_samplerate;

  136.     uint_fast32_t bitrate_maximum;

  137.     uint_fast32_t bitrate_nominal;

  138.     uint_fast32_t bitrate_minimum;

  139.     uint_fast32_t blocksize[2];

  140.     const float  *win[2];

  141.     uint_fast16_t codebook_count;

  142.     vorbis_codebook *codebooks;

  143.     uint_fast8_t  floor_count;

  144.     vorbis_floor *floors;

  145.     uint_fast8_t  residue_count;

  146.     vorbis_residue *residues;

  147.     uint_fast8_t  mapping_count;

  148.     vorbis_mapping *mappings;

  149.     uint_fast8_t  mode_count;

  150.     vorbis_mode  *modes;

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

  152.     uint_fast8_t  previous_window;

  153.     float        *channel_residues;

  154.     float        *channel_floors;

  155.     float        *saved;

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

  157.     uint_fast32_t exp_bias;

  158. } vorbis_context;

  159. 

  160. /* Helper functions */

  161. 

  162. #define BARK(x) \

  163.     (13.1f * atan(0.00074f * (x)) + 2.24f * atan(1.85e-8f * (x) * (x)) + 1e-4f * (x))

  164. 

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

  166. #define VALIDATE_INDEX(idx, limit) \

  167.     if (idx >= limit) {\

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

  169.                idx_err_str,\

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

  171.         return -1;\

  172.     }

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

  174.     {\

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

  176.         VALIDATE_INDEX(idx, limit)\

  177.     }

  178. 

  179. static float vorbisfloat2float(uint_fast32_t val)

  180. {

  181.     double mant = val & 0x1fffff;

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

  183.     if (val & 0x80000000)

  184.         mant = -mant;

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

  186. }

  187. 

  188. 

  189. // Free all allocated memory -----------------------------------------

  190. 

  191. static void vorbis_free(vorbis_context *vc)

  192. {

  193.     int_fast16_t i;

  194. 

  195.     av_freep(&vc->channel_residues);

  196.     av_freep(&vc->channel_floors);

  197.     av_freep(&vc->saved);

  198. 

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

  200.         av_free(vc->residues[i].classifs);

  201.     av_freep(&vc->residues);

  202.     av_freep(&vc->modes);

  203. 

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

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

  206. 

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

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

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

  210.     }

  211.     av_freep(&vc->codebooks);

  212. 

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

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

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

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

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

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

  219.         } else {

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

  221.         }

  222.     }

  223.     av_freep(&vc->floors);

  224. 

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

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

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

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

  229.     }

  230.     av_freep(&vc->mappings);

  231. }

  232. 

  233. // Parse setup header -------------------------------------------------

  234. 

  235. // Process codebooks part

  236. 

  237. static int vorbis_parse_setup_hdr_codebooks(vorbis_context *vc)

  238. {

  239.     uint_fast16_t cb;

  240.     uint8_t  *tmp_vlc_bits;

  241.     uint32_t *tmp_vlc_codes;

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

  243.     uint_fast16_t *codebook_multiplicands;

  244. 

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

  246. 

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

  248. 

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

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

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

  252.     codebook_multiplicands = av_malloc(V_MAX_VLCS * sizeof(*codebook_multiplicands));

  253. 

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

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

  256.         uint_fast8_t ordered;

  257.         uint_fast32_t t, used_entries = 0;

  258.         uint_fast32_t entries;

  259. 

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

  261. 

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

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

  264.             goto error;

  265.         }

  266. 

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

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

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

  270.             goto error;

  271.         }

  272.         entries = get_bits(gb, 24);

  273.         if (entries > V_MAX_VLCS) {

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

  275.             goto error;

  276.         }

  277. 

  278.         ordered = get_bits1(gb);

  279. 

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

  281. 

  282.         if (!ordered) {

  283.             uint_fast16_t ce;

  284.             uint_fast8_t  flag;

  285.             uint_fast8_t  sparse = get_bits1(gb);

  286. 

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

  288. 

  289.             if (sparse) {

  290.                 AV_DEBUG(" sparse \n");

  291. 

  292.                 used_entries = 0;

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

  294.                     flag = get_bits1(gb);

  295.                     if (flag) {

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

  297.                         ++used_entries;

  298.                     } else

  299.                         tmp_vlc_bits[ce] = 0;

  300.                 }

  301.             } else {

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

  303. 

  304.                 used_entries = entries;

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

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

  307.             }

  308.         } else {

  309.             uint_fast16_t current_entry = 0;

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

  311. 

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

  313. 

  314.             used_entries = entries;

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

  316.                 uint_fast16_t i, number;

  317. 

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

  319. 

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

  321. 

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

  323. 

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

  325.                     if (i < used_entries)

  326.                         tmp_vlc_bits[i] = current_length;

  327. 

  328.                 current_entry+=number;

  329.             }

  330.             if (current_entry>used_entries) {

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

  332.                 goto error;

  333.             }

  334.         }

  335. 

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

  337. 

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

  339. 

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

  341. 

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

  343.             uint_fast16_t i, j, k;

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

  345. 

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

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

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

  349.             uint_fast8_t codebook_sequence_p = get_bits1(gb);

  350. 

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

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

  353. 

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

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

  356. 

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

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

  359.             }

  360. 

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

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

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

  364.                 uint_fast8_t dim = codebook_setup->dimensions;

  365. 

  366.                 if (tmp_vlc_bits[i]) {

  367.                     float last = 0.0;

  368.                     uint_fast32_t lookup_offset = i;

  369. 

  370. #ifdef V_DEBUG

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

  372. #endif

  373. 

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

  375.                         uint_fast32_t multiplicand_offset = lookup_offset % codebook_lookup_values;

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

  377.                         if (codebook_sequence_p)

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

  379.                         lookup_offset/=codebook_lookup_values;

  380.                     }

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

  382. 

  383. #ifdef V_DEBUG

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

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

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

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

  388. #endif

  389. 

  390.                     ++j;

  391.                 }

  392.             }

  393.             if (j != used_entries) {

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

  395.                 goto error;

  396.             }

  397.             entries = used_entries;

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

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

  400.             goto error;

  401.         }

  402. 

  403. // Initialize VLC table

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

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

  406.             goto error;

  407.         }

  408.         codebook_setup->maxdepth = 0;

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

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

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

  412. 

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

  414.             codebook_setup->nb_bits = V_NB_BITS2;

  415.         else

  416.             codebook_setup->nb_bits = V_NB_BITS;

  417. 

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

  419. 

  420.         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)) {

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

  422.             goto error;

  423.         }

  424.     }

  425. 

  426.     av_free(tmp_vlc_bits);

  427.     av_free(tmp_vlc_codes);

  428.     av_free(codebook_multiplicands);

  429.     return 0;

  430. 

  431. // Error:

  432. error:

  433.     av_free(tmp_vlc_bits);

  434.     av_free(tmp_vlc_codes);

  435.     av_free(codebook_multiplicands);

  436.     return -1;

  437. }

  438. 

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

  440. 

  441. static int vorbis_parse_setup_hdr_tdtransforms(vorbis_context *vc)

  442. {

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

  444.     uint_fast8_t i;

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

  446. 

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

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

  449. 

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

  451. 

  452.         if (vorbis_tdtransform) {

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

  454.             return -1;

  455.         }

  456.     }

  457.     return 0;

  458. }

  459. 

  460. // Process floors part

  461. 

  462. static uint_fast8_t vorbis_floor0_decode(vorbis_context *vc,

  463.                                          vorbis_floor_data *vfu, float *vec);

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

  465. static uint_fast8_t vorbis_floor1_decode(vorbis_context *vc,

  466.                                          vorbis_floor_data *vfu, float *vec);

  467. static int vorbis_parse_setup_hdr_floors(vorbis_context *vc)

  468. {

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

  470.     uint_fast16_t i,j,k;

  471. 

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

  473. 

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

  475. 

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

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

  478. 

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

  480. 

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

  482. 

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

  484.             int maximum_class = -1;

  485.             uint_fast8_t  rangebits;

  486.             uint_fast16_t floor1_values = 2;

  487. 

  488.             floor_setup->decode = vorbis_floor1_decode;

  489. 

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

  491. 

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

  493. 

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

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

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

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

  498. 

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

  500. 

  501.             }

  502. 

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

  504. 

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

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

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

  508. 

  509.                 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]);

  510. 

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

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

  513. 

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

  515.                 }

  516. 

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

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

  519.                     if (bits != -1)

  520.                         VALIDATE_INDEX(bits, vc->codebook_count)

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

  522. 

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

  524.                 }

  525.             }

  526. 

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

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

  529. 

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

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

  532. 

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

  534. 

  535. 

  536.             rangebits = get_bits(gb, 4);

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

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

  539. 

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

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

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

  543. 

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

  545.                 }

  546.             }

  547. 

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

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

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

  551.             uint_fast8_t max_codebook_dim = 0;

  552. 

  553.             floor_setup->decode = vorbis_floor0_decode;

  554. 

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

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

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

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

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

  560.              * 2^0 - 1 == 0                             */

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

  562.               av_log(vc->avccontext, AV_LOG_ERROR,

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

  564.               return -1;

  565.             }

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

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

  568. 

  569.             /* allocate mem for booklist */

  570.             floor_setup->data.t0.book_list =

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

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

  573.                 return -1;

  574.             /* read book indexes */

  575.             {

  576.                 int idx;

  577.                 uint_fast8_t book_idx;

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

  579.                     GET_VALIDATED_INDEX(book_idx, 8, vc->codebook_count)

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

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

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

  583.                 }

  584.             }

  585. 

  586.             create_map(vc, i);

  587. 

  588.             /* allocate mem for lsp coefficients */

  589.             {

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

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

  592.                 floor_setup->data.t0.lsp =

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

  594.                               * sizeof(float));

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

  596.                     return -1;

  597.             }

  598. 

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

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

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

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

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

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

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

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

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

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

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

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

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

  612.             {

  613.               int idx;

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

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

  616.                            idx+1,

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

  618.               }

  619.             }

  620. #endif

  621.         } else {

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

  623.             return -1;

  624.         }

  625.     }

  626.     return 0;

  627. }

  628. 

  629. // Process residues part

  630. 

  631. static int vorbis_parse_setup_hdr_residues(vorbis_context *vc)

  632. {

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

  634.     uint_fast8_t i, j, k;

  635. 

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

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

  638. 

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

  640. 

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

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

  643.         uint_fast8_t cascade[64];

  644.         uint_fast8_t high_bits;

  645.         uint_fast8_t low_bits;

  646. 

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

  648. 

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

  650. 

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

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

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

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

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

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

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

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

  659.             return -1;

  660.         }

  661. 

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

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

  664. 

  665.         res_setup->ptns_to_read =

  666.             (res_setup->end - res_setup->begin) / res_setup->partition_size;

  667.         res_setup->classifs = av_malloc(res_setup->ptns_to_read *

  668.                                         vc->audio_channels *

  669.                                         sizeof(*res_setup->classifs));

  670.         if (!res_setup->classifs)

  671.             return AVERROR(ENOMEM);

  672. 

  673.         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,

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

  675. 

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

  677.             high_bits = 0;

  678.             low_bits  = get_bits(gb, 3);

  679.             if (get_bits1(gb))

  680.                 high_bits = get_bits(gb, 5);

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

  682. 

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

  684.         }

  685. 

  686.         res_setup->maxpass = 0;

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

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

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

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

  691. 

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

  693. 

  694.                     if (k>res_setup->maxpass)

  695.                         res_setup->maxpass = k;

  696.                 } else {

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

  698.                 }

  699.             }

  700.         }

  701.     }

  702.     return 0;

  703. }

  704. 

  705. // Process mappings part

  706. 

  707. static int vorbis_parse_setup_hdr_mappings(vorbis_context *vc)

  708. {

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

  710.     uint_fast8_t i, j;

  711. 

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

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

  714. 

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

  716. 

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

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

  719. 

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

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

  722.             return -1;

  723.         }

  724.         if (get_bits1(gb)) {

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

  726.         } else {

  727.             mapping_setup->submaps = 1;

  728.         }

  729. 

  730.         if (get_bits1(gb)) {

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

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

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

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

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

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

  737.             }

  738.         } else {

  739.             mapping_setup->coupling_steps = 0;

  740.         }

  741. 

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

  743. 

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

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

  746.             return -1; // following spec.

  747.         }

  748. 

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

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

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

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

  753.         }

  754. 

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

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

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

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

  759. 

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

  761.         }

  762.     }

  763.     return 0;

  764. }

  765. 

  766. // Process modes part

  767. 

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

  769. {

  770.     vorbis_floor *floors = vc->floors;

  771.     vorbis_floor0 *vf;

  772.     int idx;

  773.     int_fast8_t blockflag;

  774.     int_fast32_t *map;

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

  776. 

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

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

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

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

  781. 

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

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

  784. 

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

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

  787.                              ((vf->bark_map_size) /

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

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

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

  791.         }

  792.         map[n] = -1;

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

  794.     }

  795. 

  796. #   ifdef V_DEBUG

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

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

  799.                  idx, map[idx]);

  800.     }

  801. #   endif

  802. }

  803. 

  804. static int vorbis_parse_setup_hdr_modes(vorbis_context *vc)

  805. {

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

  807.     uint_fast8_t i;

  808. 

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

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

  811. 

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

  813. 

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

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

  816. 

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

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

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

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

  821. 

  822.         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);

  823.     }

  824.     return 0;

  825. }

  826. 

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

  828. 

  829. static int vorbis_parse_setup_hdr(vorbis_context *vc)

  830. {

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

  832. 

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

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

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

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

  837.         return -1;

  838.     }

  839. 

  840.     if (vorbis_parse_setup_hdr_codebooks(vc)) {

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

  842.         return -2;

  843.     }

  844.     if (vorbis_parse_setup_hdr_tdtransforms(vc)) {

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

  846.         return -3;

  847.     }

  848.     if (vorbis_parse_setup_hdr_floors(vc)) {

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

  850.         return -4;

  851.     }

  852.     if (vorbis_parse_setup_hdr_residues(vc)) {

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

  854.         return -5;

  855.     }

  856.     if (vorbis_parse_setup_hdr_mappings(vc)) {

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

  858.         return -6;

  859.     }

  860.     if (vorbis_parse_setup_hdr_modes(vc)) {

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

  862.         return -7;

  863.     }

  864.     if (!get_bits1(gb)) {

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

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

  867.     }

  868. 

  869.     return 0;

  870. }

  871. 

  872. // Process the identification header

  873. 

  874. static int vorbis_parse_id_hdr(vorbis_context *vc)

  875. {

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

  877.     uint_fast8_t bl0, bl1;

  878. 

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

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

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

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

  883.         return -1;

  884.     }

  885. 

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

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

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

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

  890.         return -1;

  891.     }

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

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

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

  895.         return -1;

  896.     }

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

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

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

  900.     bl0 = get_bits(gb, 4);

  901.     bl1 = get_bits(gb, 4);

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

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

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

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

  906.         return -3;

  907.     }

  908.     // output format int16

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

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

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

  912.         return -4;

  913.     }

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

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

  916. 

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

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

  919.         return -2;

  920.     }

  921. 

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

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

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

  925.     vc->previous_window  = 0;

  926. 

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

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

  929. 

  930.     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 ",

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

  932. 

  933. /*

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

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

  936.         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)));

  937.     }

  938. */

  939. 

  940.     return 0;

  941. }

  942. 

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

  944. 

  945. static av_cold int vorbis_decode_init(AVCodecContext *avccontext)

  946. {

  947.     vorbis_context *vc = avccontext->priv_data ;

  948.     uint8_t *headers   = avccontext->extradata;

  949.     int headers_len    = avccontext->extradata_size;

  950.     uint8_t *header_start[3];

  951.     int header_len[3];

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

  953.     int hdr_type;

  954. 

  955.     vc->avccontext = avccontext;

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

  957. 

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

  959.         vc->add_bias = 385;

  960.         vc->exp_bias = 0;

  961.     } else {

  962.         vc->add_bias = 0;

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

  964.     }

  965. 

  966.     if (!headers_len) {

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

  968.         return -1;

  969.     }

  970. 

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

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

  973.         return -1;

  974.     }

  975. 

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

  977.     hdr_type = get_bits(gb, 8);

  978.     if (hdr_type != 1) {

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

  980.         return -1;

  981.     }

  982.     if (vorbis_parse_id_hdr(vc)) {

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

  984.         vorbis_free(vc);

  985.         return -1;

  986.     }

  987. 

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

  989.     hdr_type = get_bits(gb, 8);

  990.     if (hdr_type != 5) {

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

  992.         vorbis_free(vc);

  993.         return -1;

  994.     }

  995.     if (vorbis_parse_setup_hdr(vc)) {

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

  997.         vorbis_free(vc);

  998.         return -1;

  999.     }

  1000. 

  1001.     if (vc->audio_channels > 8)

  1002.         avccontext->channel_layout = 0;

  1003.     else

  1004.         avccontext->channel_layout = ff_vorbis_channel_layouts[vc->audio_channels - 1];

  1005. 

  1006.     avccontext->channels    = vc->audio_channels;

  1007.     avccontext->sample_rate = vc->audio_samplerate;

  1008.     avccontext->frame_size  = FFMIN(vc->blocksize[0], vc->blocksize[1]) >> 2;

  1009.     avccontext->sample_fmt  = SAMPLE_FMT_S16;

  1010. 

  1011.     return 0 ;

  1012. }

  1013. 

  1014. // Decode audiopackets -------------------------------------------------

  1015. 

  1016. // Read and decode floor

  1017. 

  1018. static uint_fast8_t vorbis_floor0_decode(vorbis_context *vc,

  1019.                                          vorbis_floor_data *vfu, float *vec)

  1020. {

  1021.     vorbis_floor0 *vf = &vfu->t0;

  1022.     float *lsp = vf->lsp;

  1023.     uint_fast32_t amplitude;

  1024.     uint_fast32_t book_idx;

  1025.     uint_fast8_t blockflag = vc->modes[vc->mode_number].blockflag;

  1026. 

  1027.     amplitude = get_bits(&vc->gb, vf->amplitude_bits);

  1028.     if (amplitude > 0) {

  1029.         float last = 0;

  1030.         uint_fast16_t lsp_len = 0;

  1031.         uint_fast16_t idx;

  1032.         vorbis_codebook codebook;

  1033. 

  1034.         book_idx = get_bits(&vc->gb, ilog(vf->num_books));

  1035.         if (book_idx >= vf->num_books) {

  1036.             av_log(vc->avccontext, AV_LOG_ERROR,

  1037.                     "floor0 dec: booknumber too high!\n");

  1038.             book_idx =  0;

  1039.             //FIXME: look above

  1040.         }

  1041.         AV_DEBUG("floor0 dec: booknumber: %u\n", book_idx);

  1042.         codebook = vc->codebooks[vf->book_list[book_idx]];

  1043. 

  1044.         while (lsp_len<vf->order) {

  1045.             int vec_off;

  1046. 

  1047.             AV_DEBUG("floor0 dec: book dimension: %d\n", codebook.dimensions);

  1048.             AV_DEBUG("floor0 dec: maximum depth: %d\n", codebook.maxdepth);

  1049.             /* read temp vector */

  1050.             vec_off = get_vlc2(&vc->gb, codebook.vlc.table,

  1051.                                codebook.nb_bits, codebook.maxdepth)

  1052.                       * codebook.dimensions;

  1053.             AV_DEBUG("floor0 dec: vector offset: %d\n", vec_off);

  1054.             /* copy each vector component and add last to it */

  1055.             for (idx = 0; idx < codebook.dimensions; ++idx)

  1056.                 lsp[lsp_len+idx] = codebook.codevectors[vec_off+idx] + last;

  1057.             last = lsp[lsp_len+idx-1]; /* set last to last vector component */

  1058. 

  1059.             lsp_len += codebook.dimensions;

  1060.         }

  1061. #ifdef V_DEBUG

  1062.         /* DEBUG: output lsp coeffs */

  1063.         {

  1064.             int idx;

  1065.             for (idx = 0; idx < lsp_len; ++idx)

  1066.                 AV_DEBUG("floor0 dec: coeff at %d is %f\n", idx, lsp[idx]);

  1067.         }

  1068. #endif

  1069. 

  1070.         /* synthesize floor output vector */

  1071.         {

  1072.             int i;

  1073.             int order = vf->order;

  1074.             float wstep = M_PI / vf->bark_map_size;

  1075. 

  1076.             for (i = 0; i < order; i++)

  1077.                 lsp[i] = 2.0f * cos(lsp[i]);

  1078. 

  1079.             AV_DEBUG("floor0 synth: map_size = %d; m = %d; wstep = %f\n",

  1080.                      vf->map_size, order, wstep);

  1081. 

  1082.             i = 0;

  1083.             while (i < vf->map_size[blockflag]) {

  1084.                 int j, iter_cond = vf->map[blockflag][i];

  1085.                 float p = 0.5f;

  1086.                 float q = 0.5f;

  1087.                 float two_cos_w = 2.0f * cos(wstep * iter_cond); // needed all times

  1088. 

  1089.                 /* similar part for the q and p products */

  1090.                 for (j = 0; j + 1 < order; j += 2) {

  1091.                     q *= lsp[j]     - two_cos_w;

  1092.                     p *= lsp[j + 1] - two_cos_w;

  1093.                 }

  1094.                 if (j == order) { // even order

  1095.                     p *= p * (2.0f - two_cos_w);

  1096.                     q *= q * (2.0f + two_cos_w);

  1097.                 } else { // odd order

  1098.                     q *= two_cos_w-lsp[j]; // one more time for q

  1099. 

  1100.                     /* final step and square */

  1101.                     p *= p * (4.f - two_cos_w * two_cos_w);

  1102.                     q *= q;

  1103.                 }

  1104. 

  1105.                 /* calculate linear floor value */

  1106.                 {

  1107.                     q = exp((((amplitude*vf->amplitude_offset) /

  1108.                               (((1 << vf->amplitude_bits) - 1) * sqrt(p + q)))

  1109.                              - vf->amplitude_offset) * .11512925f);

  1110.                 }

  1111. 

  1112.                 /* fill vector */

  1113.                 do {

  1114.                     vec[i] = q; ++i;

  1115.                 } while (vf->map[blockflag][i] == iter_cond);

  1116.             }

  1117.         }

  1118.     } else {

  1119.         /* this channel is unused */

  1120.         return 1;

  1121.     }

  1122. 

  1123.     AV_DEBUG(" Floor0 decoded\n");

  1124. 

  1125.     return 0;

  1126. }

  1127. 

  1128. static uint_fast8_t vorbis_floor1_decode(vorbis_context *vc,

  1129.                                          vorbis_floor_data *vfu, float *vec)

  1130. {

  1131.     vorbis_floor1 *vf = &vfu->t1;

  1132.     GetBitContext *gb = &vc->gb;

  1133.     uint_fast16_t range_v[4] = { 256, 128, 86, 64 };

  1134.     uint_fast16_t range = range_v[vf->multiplier-1];

  1135.     uint_fast16_t floor1_Y[258];

  1136.     uint_fast16_t floor1_Y_final[258];

  1137.     int floor1_flag[258];

  1138.     uint_fast8_t class_;

  1139.     uint_fast8_t cdim;

  1140.     uint_fast8_t cbits;

  1141.     uint_fast8_t csub;

  1142.     uint_fast8_t cval;

  1143.     int_fast16_t book;

  1144.     uint_fast16_t offset;

  1145.     uint_fast16_t i,j;

  1146.     /*u*/int_fast16_t adx, ady, off, predicted; // WTF ? dy/adx =  (unsigned)dy/adx ?

  1147.     int_fast16_t dy, err;

  1148. 

  1149. 

  1150.     if (!get_bits1(gb)) // silence

  1151.         return 1;

  1152. 

  1153. // Read values (or differences) for the floor's points

  1154. 

  1155.     floor1_Y[0] = get_bits(gb, ilog(range - 1));

  1156.     floor1_Y[1] = get_bits(gb, ilog(range - 1));

  1157. 

  1158.     AV_DEBUG("floor 0 Y %d floor 1 Y %d \n", floor1_Y[0], floor1_Y[1]);

  1159. 

  1160.     offset = 2;

  1161.     for (i = 0; i < vf->partitions; ++i) {

  1162.         class_ = vf->partition_class[i];

  1163.         cdim   = vf->class_dimensions[class_];

  1164.         cbits  = vf->class_subclasses[class_];

  1165.         csub = (1 << cbits) - 1;

  1166.         cval = 0;

  1167. 

  1168.         AV_DEBUG("Cbits %d \n", cbits);

  1169. 

  1170.         if (cbits) // this reads all subclasses for this partition's class

  1171.             cval = get_vlc2(gb, vc->codebooks[vf->class_masterbook[class_]].vlc.table,

  1172.                             vc->codebooks[vf->class_masterbook[class_]].nb_bits, 3);

  1173. 

  1174.         for (j = 0; j < cdim; ++j) {

  1175.             book = vf->subclass_books[class_][cval & csub];

  1176. 

  1177.             AV_DEBUG("book %d Cbits %d cval %d  bits:%d \n", book, cbits, cval, get_bits_count(gb));

  1178. 

  1179.             cval = cval >> cbits;

  1180.             if (book > -1) {

  1181.                 floor1_Y[offset+j] = get_vlc2(gb, vc->codebooks[book].vlc.table,

  1182.                 vc->codebooks[book].nb_bits, 3);

  1183.             } else {

  1184.                 floor1_Y[offset+j] = 0;

  1185.             }

  1186. 

  1187.             AV_DEBUG(" floor(%d) = %d \n", vf->list[offset+j].x, floor1_Y[offset+j]);

  1188.         }

  1189.         offset+=cdim;

  1190.     }

  1191. 

  1192. // Amplitude calculation from the differences

  1193. 

  1194.     floor1_flag[0] = 1;

  1195.     floor1_flag[1] = 1;

  1196.     floor1_Y_final[0] = floor1_Y[0];

  1197.     floor1_Y_final[1] = floor1_Y[1];

  1198. 

  1199.     for (i = 2; i < vf->x_list_dim; ++i) {

  1200.         uint_fast16_t val, highroom, lowroom, room;

  1201.         uint_fast16_t high_neigh_offs;

  1202.         uint_fast16_t low_neigh_offs;

  1203. 

  1204.         low_neigh_offs  = vf->list[i].low;

  1205.         high_neigh_offs = vf->list[i].high;

  1206.         dy  = floor1_Y_final[high_neigh_offs] - floor1_Y_final[low_neigh_offs];  // render_point begin

  1207.         adx = vf->list[high_neigh_offs].x - vf->list[low_neigh_offs].x;

  1208.         ady = FFABS(dy);

  1209.         err = ady * (vf->list[i].x - vf->list[low_neigh_offs].x);

  1210.         off = (int16_t)err / (int16_t)adx;

  1211.         if (dy < 0) {

  1212.             predicted = floor1_Y_final[low_neigh_offs] - off;

  1213.         } else {

  1214.             predicted = floor1_Y_final[low_neigh_offs] + off;

  1215.         } // render_point end

  1216. 

  1217.         val = floor1_Y[i];

  1218.         highroom = range-predicted;

  1219.         lowroom  = predicted;

  1220.         if (highroom < lowroom) {

  1221.             room = highroom * 2;

  1222.         } else {

  1223.             room = lowroom * 2;   // SPEC mispelling

  1224.         }

  1225.         if (val) {

  1226.             floor1_flag[low_neigh_offs]  = 1;

  1227.             floor1_flag[high_neigh_offs] = 1;

  1228.             floor1_flag[i]               = 1;

  1229.             if (val >= room) {

  1230.                 if (highroom > lowroom) {

  1231.                     floor1_Y_final[i] = val - lowroom + predicted;

  1232.                 } else {

  1233.                     floor1_Y_final[i] = predicted - val + highroom - 1;

  1234.                 }

  1235.             } else {

  1236.                 if (val & 1) {

  1237.                     floor1_Y_final[i] = predicted - (val + 1) / 2;

  1238.                 } else {

  1239.                     floor1_Y_final[i] = predicted + val / 2;

  1240.                 }

  1241.             }

  1242.         } else {

  1243.             floor1_flag[i]    = 0;

  1244.             floor1_Y_final[i] = predicted;

  1245.         }

  1246. 

  1247.         AV_DEBUG(" Decoded floor(%d) = %d / val %d \n", vf->list[i].x, floor1_Y_final[i], val);

  1248.     }

  1249. 

  1250. // Curve synth - connect the calculated dots and convert from dB scale FIXME optimize ?

  1251. 

  1252.     ff_vorbis_floor1_render_list(vf->list, vf->x_list_dim, floor1_Y_final, floor1_flag, vf->multiplier, vec, vf->list[1].x);

  1253. 

  1254.     AV_DEBUG(" Floor decoded\n");

  1255. 

  1256.     return 0;

  1257. }

  1258. 

  1259. // Read and decode residue

  1260. 

  1261. static av_always_inline int vorbis_residue_decode_internal(vorbis_context *vc,

  1262.                                                            vorbis_residue *vr,

  1263.                                                            uint_fast8_t ch,

  1264.                                                            uint_fast8_t *do_not_decode,

  1265.                                                            float *vec,

  1266.                                                            uint_fast16_t vlen,

  1267.                                                            int vr_type)

  1268. {

  1269.     GetBitContext *gb = &vc->gb;

  1270.     uint_fast8_t c_p_c = vc->codebooks[vr->classbook].dimensions;

  1271.     uint_fast16_t ptns_to_read = vr->ptns_to_read;

  1272.     uint8_t *classifs = vr->classifs;

  1273.     uint_fast8_t pass;

  1274.     uint_fast8_t ch_used;

  1275.     uint_fast8_t i,j,l;

  1276.     uint_fast16_t k;

  1277. 

  1278.     if (vr_type == 2) {

  1279.         for (j = 1; j < ch; ++j)

  1280.             do_not_decode[0] &= do_not_decode[j];  // FIXME - clobbering input

  1281.         if (do_not_decode[0])

  1282.             return 0;

  1283.         ch_used = 1;

  1284.     } else {

  1285.         ch_used = ch;

  1286.     }

  1287. 

  1288.     AV_DEBUG(" residue type 0/1/2 decode begin, ch: %d  cpc %d  \n", ch, c_p_c);

  1289. 

  1290.     for (pass = 0; pass <= vr->maxpass; ++pass) { // FIXME OPTIMIZE?

  1291.         uint_fast16_t voffset;

  1292.         uint_fast16_t partition_count;

  1293.         uint_fast16_t j_times_ptns_to_read;

  1294. 

  1295.         voffset = vr->begin;

  1296.         for (partition_count = 0; partition_count < ptns_to_read;) {  // SPEC        error

  1297.             if (!pass) {

  1298.                 uint_fast32_t inverse_class = ff_inverse[vr->classifications];

  1299.                 for (j_times_ptns_to_read = 0, j = 0; j < ch_used; ++j) {

  1300.                     if (!do_not_decode[j]) {

  1301.                         uint_fast32_t temp = get_vlc2(gb, vc->codebooks[vr->classbook].vlc.table,

  1302.                         vc->codebooks[vr->classbook].nb_bits, 3);

  1303. 

  1304.                         AV_DEBUG("Classword: %d \n", temp);

  1305. 

  1306.                         assert(vr->classifications > 1 && temp <= 65536); //needed for inverse[]

  1307.                         for (i = 0; i < c_p_c; ++i) {

  1308.                             uint_fast32_t temp2;

  1309. 

  1310.                             temp2 = (((uint_fast64_t)temp) * inverse_class) >> 32;

  1311.                             if (partition_count + c_p_c - 1 - i < ptns_to_read)

  1312.                                 classifs[j_times_ptns_to_read + partition_count + c_p_c - 1 - i] = temp - temp2 * vr->classifications;

  1313.                             temp = temp2;

  1314.                         }

  1315.                     }

  1316.                     j_times_ptns_to_read += ptns_to_read;

  1317.                 }

  1318.             }

  1319.             for (i = 0; (i < c_p_c) && (partition_count < ptns_to_read); ++i) {

  1320.                 for (j_times_ptns_to_read = 0, j = 0; j < ch_used; ++j) {

  1321.                     uint_fast16_t voffs;

  1322. 

  1323.                     if (!do_not_decode[j]) {

  1324.                         uint_fast8_t vqclass = classifs[j_times_ptns_to_read+partition_count];

  1325.                         int_fast16_t vqbook = vr->books[vqclass][pass];

  1326. 

  1327.                         if (vqbook >= 0 && vc->codebooks[vqbook].codevectors) {

  1328.                             uint_fast16_t coffs;

  1329.                             unsigned dim =  vc->codebooks[vqbook].dimensions; // not uint_fast8_t: 64bit is slower here on amd64

  1330.                             uint_fast16_t step = dim == 1 ? vr->partition_size

  1331.                                                           : FASTDIV(vr->partition_size, dim);

  1332.                             vorbis_codebook codebook = vc->codebooks[vqbook];

  1333. 

  1334.                             if (vr_type == 0) {

  1335. 

  1336.                                 voffs = voffset+j*vlen;

  1337.                                 for (k = 0; k < step; ++k) {

  1338.                                     coffs = get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * dim;

  1339.                                     for (l = 0; l < dim; ++l)

  1340.                                         vec[voffs + k + l * step] += codebook.codevectors[coffs + l];  // FPMATH

  1341.                                 }

  1342.                             } else if (vr_type == 1) {

  1343.                                 voffs = voffset + j * vlen;

  1344.                                 for (k = 0; k < step; ++k) {

  1345.                                     coffs = get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * dim;

  1346.                                     for (l = 0; l < dim; ++l, ++voffs) {

  1347.                                         vec[voffs]+=codebook.codevectors[coffs+l];  // FPMATH

  1348. 

  1349.                                         AV_DEBUG(" pass %d offs: %d curr: %f change: %f cv offs.: %d  \n", pass, voffs, vec[voffs], codebook.codevectors[coffs+l], coffs);

  1350.                                     }

  1351.                                 }

  1352.                             } else if (vr_type == 2 && ch == 2 && (voffset & 1) == 0 && (dim & 1) == 0) { // most frequent case optimized

  1353.                                 voffs = voffset >> 1;

  1354. 

  1355.                                 if (dim == 2) {

  1356.                                     for (k = 0; k < step; ++k) {

  1357.                                         coffs = get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * 2;

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

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

  1360.                                     }

  1361.                                 } else if (dim == 4) {

  1362.                                     for (k = 0; k < step; ++k, voffs += 2) {

  1363.                                         coffs = get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * 4;

  1364.                                         vec[voffs           ] += codebook.codevectors[coffs    ];  // FPMATH

  1365.                                         vec[voffs + 1       ] += codebook.codevectors[coffs + 2];  // FPMATH

  1366.                                         vec[voffs + vlen    ] += codebook.codevectors[coffs + 1];  // FPMATH

  1367.                                         vec[voffs + vlen + 1] += codebook.codevectors[coffs + 3];  // FPMATH

  1368.                                     }

  1369.                                 } else

  1370.                                 for (k = 0; k < step; ++k) {

  1371.                                     coffs = get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * dim;

  1372.                                     for (l = 0; l < dim; l += 2, voffs++) {

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

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

  1375. 

  1376.                                         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);

  1377.                                     }

  1378.                                 }

  1379. 

  1380.                             } else if (vr_type == 2) {

  1381.                                 voffs = voffset;

  1382. 

  1383.                                 for (k = 0; k < step; ++k) {

  1384.                                     coffs = get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * dim;

  1385.                                     for (l = 0; l < dim; ++l, ++voffs) {

  1386.                                         vec[voffs / ch + (voffs % ch) * vlen] += codebook.codevectors[coffs + l];  // FPMATH FIXME use if and counter instead of / and %

  1387. 

  1388.                                         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);

  1389.                                     }

  1390.                                 }

  1391.                             }

  1392.                         }

  1393.                     }

  1394.                     j_times_ptns_to_read += ptns_to_read;

  1395.                 }

  1396.                 ++partition_count;

  1397.                 voffset += vr->partition_size;

  1398.             }

  1399.         }

  1400.     }

  1401.     return 0;

  1402. }

  1403. 

  1404. static inline int vorbis_residue_decode(vorbis_context *vc, vorbis_residue *vr,

  1405.                                         uint_fast8_t ch,

  1406.                                         uint_fast8_t *do_not_decode,

  1407.                                         float *vec, uint_fast16_t vlen)

  1408. {

  1409.     if (vr->type == 2)

  1410.         return vorbis_residue_decode_internal(vc, vr, ch, do_not_decode, vec, vlen, 2);

  1411.     else if (vr->type == 1)

  1412.         return vorbis_residue_decode_internal(vc, vr, ch, do_not_decode, vec, vlen, 1);

  1413.     else if (vr->type == 0)

  1414.         return vorbis_residue_decode_internal(vc, vr, ch, do_not_decode, vec, vlen, 0);

  1415.     else {

  1416.         av_log(vc->avccontext, AV_LOG_ERROR, " Invalid residue type while residue decode?! \n");

  1417.         return -1;

  1418.     }

  1419. }

  1420. 

  1421. void vorbis_inverse_coupling(float *mag, float *ang, int blocksize)

  1422. {

  1423.     int i;

  1424.     for (i = 0;  i < blocksize;  i++) {

  1425.         if (mag[i] > 0.0) {

  1426.             if (ang[i] > 0.0) {

  1427.                 ang[i] = mag[i] - ang[i];

  1428.             } else {

  1429.                 float temp = ang[i];

  1430.                 ang[i]     = mag[i];

  1431.                 mag[i]    += temp;

  1432.             }

  1433.         } else {

  1434.             if (ang[i] > 0.0) {

  1435.                 ang[i] += mag[i];

  1436.             } else {

  1437.                 float temp = ang[i];

  1438.                 ang[i]     = mag[i];

  1439.                 mag[i]    -= temp;

  1440.             }

  1441.         }

  1442.     }

  1443. }

  1444. 

  1445. static void copy_normalize(float *dst, float *src, int len, int exp_bias,

  1446.                            float add_bias)

  1447. {

  1448.     int i;

  1449.     if (exp_bias) {

  1450.         memcpy(dst, src, len * sizeof(float));

  1451.     } else {

  1452.         for (i = 0; i < len; i++)

  1453.             dst[i] = src[i] + add_bias;

  1454.     }

  1455. }

  1456. 

  1457. // Decode the audio packet using the functions above

  1458. 

  1459. static int vorbis_parse_audio_packet(vorbis_context *vc)

  1460. {

  1461.     GetBitContext *gb = &vc->gb;

  1462. 

  1463.     uint_fast8_t previous_window = vc->previous_window;

  1464.     uint_fast8_t mode_number;

  1465.     uint_fast8_t blockflag;

  1466.     uint_fast16_t blocksize;

  1467.     int_fast32_t i,j;

  1468.     uint_fast8_t no_residue[255];

  1469.     uint_fast8_t do_not_decode[255];

  1470.     vorbis_mapping *mapping;

  1471.     float *ch_res_ptr   = vc->channel_residues;

  1472.     float *ch_floor_ptr = vc->channel_floors;

  1473.     uint_fast8_t res_chan[255];

  1474.     uint_fast8_t res_num = 0;

  1475.     int_fast16_t retlen  = 0;

  1476.     float fadd_bias = vc->add_bias;

  1477. 

  1478.     if (get_bits1(gb)) {

  1479.         av_log(vc->avccontext, AV_LOG_ERROR, "Not a Vorbis I audio packet.\n");

  1480.         return -1; // packet type not audio

  1481.     }

  1482. 

  1483.     if (vc->mode_count == 1) {

  1484.         mode_number = 0;

  1485.     } else {

  1486.         GET_VALIDATED_INDEX(mode_number, ilog(vc->mode_count-1), vc->mode_count)

  1487.     }

  1488.     vc->mode_number = mode_number;

  1489.     mapping = &vc->mappings[vc->modes[mode_number].mapping];

  1490. 

  1491.     AV_DEBUG(" Mode number: %d , mapping: %d , blocktype %d \n", mode_number, vc->modes[mode_number].mapping, vc->modes[mode_number].blockflag);

  1492. 

  1493.     blockflag = vc->modes[mode_number].blockflag;

  1494.     blocksize = vc->blocksize[blockflag];

  1495.     if (blockflag)

  1496.         skip_bits(gb, 2); // previous_window, next_window

  1497. 

  1498.     memset(ch_res_ptr,   0, sizeof(float) * vc->audio_channels * blocksize / 2); //FIXME can this be removed ?

  1499.     memset(ch_floor_ptr, 0, sizeof(float) * vc->audio_channels * blocksize / 2); //FIXME can this be removed ?

  1500. 

  1501. // Decode floor

  1502. 

  1503.     for (i = 0; i < vc->audio_channels; ++i) {

  1504.         vorbis_floor *floor;

  1505.         if (mapping->submaps > 1) {

  1506.             floor = &vc->floors[mapping->submap_floor[mapping->mux[i]]];

  1507.         } else {

  1508.             floor = &vc->floors[mapping->submap_floor[0]];

  1509.         }

  1510. 

  1511.         no_residue[i] = floor->decode(vc, &floor->data, ch_floor_ptr);

  1512.         ch_floor_ptr += blocksize / 2;

  1513.     }

  1514. 

  1515. // Nonzero vector propagate

  1516. 

  1517.     for (i = mapping->coupling_steps - 1; i >= 0; --i) {

  1518.         if (!(no_residue[mapping->magnitude[i]] & no_residue[mapping->angle[i]])) {

  1519.             no_residue[mapping->magnitude[i]] = 0;

  1520.             no_residue[mapping->angle[i]]     = 0;

  1521.         }

  1522.     }

  1523. 

  1524. // Decode residue

  1525. 

  1526.     for (i = 0; i < mapping->submaps; ++i) {

  1527.         vorbis_residue *residue;

  1528.         uint_fast8_t ch = 0;

  1529. 

  1530.         for (j = 0; j < vc->audio_channels; ++j) {

  1531.             if ((mapping->submaps == 1) || (i == mapping->mux[j])) {

  1532.                 res_chan[j] = res_num;

  1533.                 if (no_residue[j]) {

  1534.                     do_not_decode[ch] = 1;

  1535.                 } else {

  1536.                     do_not_decode[ch] = 0;

  1537.                 }

  1538.                 ++ch;

  1539.                 ++res_num;

  1540.             }

  1541.         }

  1542.         residue = &vc->residues[mapping->submap_residue[i]];

  1543.         vorbis_residue_decode(vc, residue, ch, do_not_decode, ch_res_ptr, blocksize/2);

  1544. 

  1545.         ch_res_ptr += ch * blocksize / 2;

  1546.     }

  1547. 

  1548. // Inverse coupling

  1549. 

  1550.     for (i = mapping->coupling_steps - 1; i >= 0; --i) { //warning: i has to be signed

  1551.         float *mag, *ang;

  1552. 

  1553.         mag = vc->channel_residues+res_chan[mapping->magnitude[i]] * blocksize / 2;

  1554.         ang = vc->channel_residues+res_chan[mapping->angle[i]]     * blocksize / 2;

  1555.         vc->dsp.vorbis_inverse_coupling(mag, ang, blocksize / 2);

  1556.     }

  1557. 

  1558. // Dotproduct, MDCT

  1559. 

  1560.     for (j = vc->audio_channels-1;j >= 0; j--) {

  1561.         ch_floor_ptr = vc->channel_floors   + j           * blocksize / 2;

  1562.         ch_res_ptr   = vc->channel_residues + res_chan[j] * blocksize / 2;

  1563.         vc->dsp.vector_fmul(ch_floor_ptr, ch_res_ptr, blocksize / 2);

  1564.         ff_imdct_half(&vc->mdct[blockflag], ch_res_ptr, ch_floor_ptr);

  1565.     }

  1566. 

  1567. // Overlap/add, save data for next overlapping  FPMATH

  1568. 

  1569.     retlen = (blocksize + vc->blocksize[previous_window]) / 4;

  1570.     for (j = 0; j < vc->audio_channels; j++) {

  1571.         uint_fast16_t bs0 = vc->blocksize[0];

  1572.         uint_fast16_t bs1 = vc->blocksize[1];

  1573.         float *residue    = vc->channel_residues + res_chan[j] * blocksize / 2;

  1574.         float *saved      = vc->saved + j * bs1 / 4;

  1575.         float *ret        = vc->channel_floors + j * retlen;

  1576.         float *buf        = residue;

  1577.         const float *win  = vc->win[blockflag & previous_window];

  1578. 

  1579.         if (blockflag == previous_window) {

  1580.             vc->dsp.vector_fmul_window(ret, saved, buf, win, fadd_bias, blocksize / 4);

  1581.         } else if (blockflag > previous_window) {

  1582.             vc->dsp.vector_fmul_window(ret, saved, buf, win, fadd_bias, bs0 / 4);

  1583.             copy_normalize(ret+bs0/2, buf+bs0/4, (bs1-bs0)/4, vc->exp_bias, fadd_bias);

  1584.         } else {

  1585.             copy_normalize(ret, saved, (bs1 - bs0) / 4, vc->exp_bias, fadd_bias);

  1586.             vc->dsp.vector_fmul_window(ret + (bs1 - bs0) / 4, saved + (bs1 - bs0) / 4, buf, win, fadd_bias, bs0 / 4);

  1587.         }

  1588.         memcpy(saved, buf + blocksize / 4, blocksize / 4 * sizeof(float));

  1589.     }

  1590. 

  1591.     vc->previous_window = blockflag;

  1592.     return retlen;

  1593. }

  1594. 

  1595. // Return the decoded audio packet through the standard api

  1596. 

  1597. static int vorbis_decode_frame(AVCodecContext *avccontext,

  1598.                                void *data, int *data_size,

  1599.                                AVPacket *avpkt)

  1600. {

  1601.     const uint8_t *buf = avpkt->data;

  1602.     int buf_size       = avpkt->size;

  1603.     vorbis_context *vc = avccontext->priv_data ;

  1604.     GetBitContext *gb = &(vc->gb);

  1605.     const float *channel_ptrs[255];

  1606.     int i;

  1607. 

  1608.     int_fast16_t len;

  1609. 

  1610.     if (!buf_size)

  1611.         return 0;

  1612. 

  1613.     AV_DEBUG("packet length %d \n", buf_size);

  1614. 

  1615.     init_get_bits(gb, buf, buf_size*8);

  1616. 

  1617.     len = vorbis_parse_audio_packet(vc);

  1618. 

  1619.     if (len <= 0) {

  1620.         *data_size = 0;

  1621.         return buf_size;

  1622.     }

  1623. 

  1624.     if (!vc->first_frame) {

  1625.         vc->first_frame = 1;

  1626.         *data_size = 0;

  1627.         return buf_size ;

  1628.     }

  1629. 

  1630.     AV_DEBUG("parsed %d bytes %d bits, returned %d samples (*ch*bits) \n", get_bits_count(gb)/8, get_bits_count(gb)%8, len);

  1631. 

  1632.     if (vc->audio_channels > 8) {

  1633.         for (i = 0; i < vc->audio_channels; i++)

  1634.             channel_ptrs[i] = vc->channel_floors + i * len;

  1635.     } else {

  1636.         for (i = 0; i < vc->audio_channels; i++)

  1637.             channel_ptrs[i] = vc->channel_floors +

  1638.                               len * ff_vorbis_channel_layout_offsets[vc->audio_channels - 1][i];

  1639.     }

  1640. 

  1641.     vc->dsp.float_to_int16_interleave(data, channel_ptrs, len, vc->audio_channels);

  1642.     *data_size = len * 2 * vc->audio_channels;

  1643. 

  1644.     return buf_size ;

  1645. }

  1646. 

  1647. // Close decoder

  1648. 

  1649. static av_cold int vorbis_decode_close(AVCodecContext *avccontext)

  1650. {

  1651.     vorbis_context *vc = avccontext->priv_data;

  1652. 

  1653.     vorbis_free(vc);

  1654. 

  1655.     return 0 ;

  1656. }

  1657. 

  1658. AVCodec vorbis_decoder = {

  1659.     "vorbis",

  1660.     AVMEDIA_TYPE_AUDIO,

  1661.     CODEC_ID_VORBIS,

  1662.     sizeof(vorbis_context),

  1663.     vorbis_decode_init,

  1664.     NULL,

  1665.     vorbis_decode_close,

  1666.     vorbis_decode_frame,

  1667.     .long_name = NULL_IF_CONFIG_SMALL("Vorbis"),

  1668.     .channel_layouts = ff_vorbis_channel_layouts,

  1669. };