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FFmpeg/libavcodec/vorbis.c

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  1. /**

  2.  * @file vorbis.c

  3.  * Vorbis I decoder

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

  5. 

  6.  * This library is free software; you can redistribute it and/or

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

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

  9.  * version 2 of the License, or (at your option) any later version.

  10.  *

  11.  * This library is distributed in the hope that it will be useful,

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

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

  14.  * Lesser General Public License for more details.

  15.  *

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

  17.  * License along with this library; if not, write to the Free Software

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

  19.  *

  20.  */

  21. 

  22. #undef V_DEBUG

  23. //#define V_DEBUG

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

  25. 

  26. #include <math.h>

  27. 

  28. #define ALT_BITSTREAM_READER_LE

  29. #include "avcodec.h"

  30. #include "bitstream.h"

  31. #include "dsputil.h"

  32. 

  33. #include "vorbis.h"

  34. 

  35. #define V_NB_BITS 8

  36. #define V_NB_BITS2 11

  37. #define V_MAX_VLCS (1<<16)

  38. 

  39. #ifndef V_DEBUG

  40. #define AV_DEBUG(...)

  41. #endif

  42. 

  43. #undef NDEBUG

  44. #include <assert.h>

  45. 

  46. /* Helper functions */

  47. 

  48. /**

  49.  *  reads 0-32 bits when using the ALT_BITSTREAM_READER_LE bitstream reader

  50.  */

  51. static unsigned int get_bits_long_le(GetBitContext *s, int n){

  52.     if(n<=17) return get_bits(s, n);

  53.     else{

  54.         int ret= get_bits(s, 16);

  55.         return ret | (get_bits(s, n-16) << 16);

  56.     }

  57. }

  58. 

  59. #define ilog(i) av_log2(2*(i))

  60. 

  61. #define BARK(x) \

  62.     (13.1f*atan(0.00074f*(x))+2.24f*atan(1.85e-8f*(x)*(x))+1e-4f*(x))

  63. 

  64. static unsigned int nth_root(unsigned int x, unsigned int n) {   // x^(1/n)

  65.     unsigned int ret=0, i, j;

  66. 

  67.     do {

  68.         ++ret;

  69.         for(i=0,j=ret;i<n-1;i++) j*=ret;

  70.     } while (j<=x);

  71. 

  72.     return (ret-1);

  73. }

  74. 

  75. static float vorbisfloat2float(uint_fast32_t val) {

  76.     double mant=val&0x1fffff;

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

  78.     if (val&0x80000000) mant=-mant;

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

  80. }

  81. 

  82. 

  83. // Generate vlc codes from vorbis huffman code lengths

  84. 

  85. static int vorbis_len2vlc(vorbis_context *vc, uint_fast8_t *bits, uint_fast32_t *codes, uint_fast32_t num) {

  86.     uint_fast32_t exit_at_level[33]={404,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,

  87.         0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};

  88. 

  89.     uint_fast8_t i,j;

  90.     uint_fast32_t code,p;

  91. 

  92. #ifdef V_DEBUG

  93.     GetBitContext gb;

  94. #endif

  95. 

  96.     for(p=0;(bits[p]==0) && (p<num);++p);

  97.     if (p==num) {

  98. //        av_log(vc->avccontext, AV_LOG_INFO, "An empty codebook. Heh?! \n");

  99.         return 0;

  100.     }

  101. 

  102.     codes[p]=0;

  103.     for(i=0;i<bits[p];++i) {

  104.         exit_at_level[i+1]=1<<i;

  105.     }

  106. 

  107. #ifdef V_DEBUG

  108.     av_log(vc->avccontext, AV_LOG_INFO, " %d. of %d code len %d code %d - ", p, num, bits[p], codes[p]);

  109.     init_get_bits(&gb, (uint_fast8_t *)&codes[p], bits[p]);

  110.     for(i=0;i<bits[p];++i) {

  111.         av_log(vc->avccontext, AV_LOG_INFO, "%s", get_bits1(&gb) ? "1" : "0");

  112.     }

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

  114. #endif

  115. 

  116.     ++p;

  117. 

  118.     for(;p<num;++p) {

  119.         if (bits[p]==0) continue;

  120.         // find corresponding exit(node which the tree can grow further from)

  121.         for(i=bits[p];i>0;--i) {

  122.             if (exit_at_level[i]) break;

  123.         }

  124.         if (!i) return 1; // overspecified tree

  125.         code=exit_at_level[i];

  126.         exit_at_level[i]=0;

  127.         // construct code (append 0s to end) and introduce new exits

  128.         for(j=i+1;j<=bits[p];++j) {

  129.             exit_at_level[j]=code+(1<<(j-1));

  130.         }

  131.         codes[p]=code;

  132. 

  133. #ifdef V_DEBUG

  134.         av_log(vc->avccontext, AV_LOG_INFO, " %d. code len %d code %d - ", p, bits[p], codes[p]);

  135.         init_get_bits(&gb, (uint_fast8_t *)&codes[p], bits[p]);

  136.         for(i=0;i<bits[p];++i) {

  137.             av_log(vc->avccontext, AV_LOG_INFO, "%s", get_bits1(&gb) ? "1" : "0");

  138.         }

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

  140. #endif

  141. 

  142.     }

  143. 

  144.     //FIXME no exits should be left (underspecified tree - ie. unused valid vlcs - not allowed by SPEC)

  145. 

  146.     return 0;

  147. }

  148. 

  149. // Free all allocated memory -----------------------------------------

  150. 

  151. static void vorbis_free(vorbis_context *vc) {

  152.     int_fast16_t i;

  153. 

  154.     av_freep(&vc->channel_residues);

  155.     av_freep(&vc->channel_floors);

  156.     av_freep(&vc->saved);

  157.     av_freep(&vc->ret);

  158.     av_freep(&vc->buf);

  159.     av_freep(&vc->buf_tmp);

  160. 

  161.     av_freep(&vc->residues);

  162.     av_freep(&vc->modes);

  163. 

  164.     ff_mdct_end(&vc->mdct0);

  165.     ff_mdct_end(&vc->mdct1);

  166. 

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

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

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

  170.     }

  171.     av_freep(&vc->codebooks);

  172. 

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

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

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

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

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

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

  179.         }

  180.         else {

  181.             av_free(vc->floors[i].data.t1.x_list);

  182.             av_free(vc->floors[i].data.t1.x_list_order);

  183.             av_free(vc->floors[i].data.t1.low_neighbour);

  184.             av_free(vc->floors[i].data.t1.high_neighbour);

  185.         }

  186.     }

  187.     av_freep(&vc->floors);

  188. 

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

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

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

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

  193.     }

  194.     av_freep(&vc->mappings);

  195. 

  196.     if(vc->exp_bias){

  197.         av_freep(&vc->swin);

  198.         av_freep(&vc->lwin);

  199.     }

  200. }

  201. 

  202. // Parse setup header -------------------------------------------------

  203. 

  204. // Process codebooks part

  205. 

  206. static int vorbis_parse_setup_hdr_codebooks(vorbis_context *vc) {

  207.     uint_fast16_t cb;

  208.     uint_fast8_t *tmp_vlc_bits;

  209.     uint_fast32_t *tmp_vlc_codes;

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

  211. 

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

  213. 

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

  215. 

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

  217.     tmp_vlc_bits=(uint_fast8_t *)av_mallocz(V_MAX_VLCS * sizeof(uint_fast8_t));

  218.     tmp_vlc_codes=(uint_fast32_t *)av_mallocz(V_MAX_VLCS * sizeof(uint_fast32_t));

  219. 

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

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

  222.         uint_fast8_t ordered;

  223.         uint_fast32_t t, used_entries=0;

  224.         uint_fast32_t entries;

  225. 

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

  227. 

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

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

  230.             goto error;

  231.         }

  232. 

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

  234.         if (codebook_setup->dimensions>16) {

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

  236.             goto error;

  237.         }

  238.         entries=get_bits(gb, 24);

  239.         if (entries>V_MAX_VLCS) {

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

  241.             goto error;

  242.         }

  243. 

  244.         ordered=get_bits1(gb);

  245. 

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

  247. 

  248.         if (!ordered) {

  249.             uint_fast16_t ce;

  250.             uint_fast8_t flag;

  251.             uint_fast8_t sparse=get_bits1(gb);

  252. 

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

  254. 

  255.             if (sparse) {

  256.                 AV_DEBUG(" sparse \n");

  257. 

  258.                 used_entries=0;

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

  260.                     flag=get_bits1(gb);

  261.                     if (flag) {

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

  263.                         ++used_entries;

  264.                     }

  265.                     else tmp_vlc_bits[ce]=0;

  266.                 }

  267.             } else {

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

  269. 

  270.                 used_entries=entries;

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

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

  273.                 }

  274.             }

  275.         } else {

  276.             uint_fast16_t current_entry=0;

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

  278. 

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

  280. 

  281.             used_entries=entries;

  282.             for(;current_entry<used_entries;++current_length) {

  283.                 uint_fast16_t i, number;

  284. 

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

  286. 

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

  288. 

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

  290. 

  291.                 for(i=current_entry;i<number+current_entry;++i) {

  292.                     if (i<used_entries) tmp_vlc_bits[i]=current_length;

  293.                 }

  294. 

  295.                 current_entry+=number;

  296.             }

  297.             if (current_entry>used_entries) {

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

  299.                 goto error;

  300.             }

  301.         }

  302. 

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

  304. 

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

  306. 

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

  308. 

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

  310.             uint_fast16_t i, j, k;

  311.             uint_fast16_t codebook_lookup_values=nth_root(entries, codebook_setup->dimensions);

  312.             uint_fast16_t codebook_multiplicands[codebook_lookup_values];

  313. 

  314.             float codebook_minimum_value=vorbisfloat2float(get_bits_long_le(gb, 32));

  315.             float codebook_delta_value=vorbisfloat2float(get_bits_long_le(gb, 32));

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

  317.             uint_fast8_t codebook_sequence_p=get_bits1(gb);

  318. 

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

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

  321. 

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

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

  324. 

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

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

  327.             }

  328. 

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

  330.             codebook_setup->codevectors=(float *)av_mallocz(used_entries*codebook_setup->dimensions * sizeof(float));

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

  332.                 uint_fast8_t dim=codebook_setup->dimensions;

  333. 

  334.                 if (tmp_vlc_bits[i]) {

  335.                     float last=0.0;

  336.                     uint_fast32_t lookup_offset=i;

  337. 

  338. #ifdef V_DEBUG

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

  340. #endif

  341. 

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

  343.                         uint_fast32_t multiplicand_offset = lookup_offset % codebook_lookup_values;

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

  345.                         if (codebook_sequence_p) {

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

  347.                         }

  348.                         lookup_offset/=codebook_lookup_values;

  349.                     }

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

  351. 

  352. #ifdef V_DEBUG

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

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

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

  356.                     }

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

  358. #endif

  359. 

  360.                     ++j;

  361.                 }

  362.             }

  363.             if (j!=used_entries) {

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

  365.                 goto error;

  366.             }

  367.             entries=used_entries;

  368.         }

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

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

  371.             goto error;

  372.         }

  373. 

  374. // Initialize VLC table

  375.         if (vorbis_len2vlc(vc, tmp_vlc_bits, tmp_vlc_codes, entries)) {

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

  377.             goto error;

  378.         }

  379.         codebook_setup->maxdepth=0;

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

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

  382. 

  383.         if(codebook_setup->maxdepth > 3*V_NB_BITS) codebook_setup->nb_bits=V_NB_BITS2;

  384.         else                                       codebook_setup->nb_bits=V_NB_BITS;

  385. 

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

  387. 

  388.         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)) {

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

  390.             goto error;

  391.         }

  392.     }

  393. 

  394.     av_free(tmp_vlc_bits);

  395.     av_free(tmp_vlc_codes);

  396.     return 0;

  397. 

  398. // Error:

  399. error:

  400.     av_free(tmp_vlc_bits);

  401.     av_free(tmp_vlc_codes);

  402.     return 1;

  403. }

  404. 

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

  406. 

  407. static int vorbis_parse_setup_hdr_tdtransforms(vorbis_context *vc) {

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

  409.     uint_fast8_t i;

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

  411. 

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

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

  414. 

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

  416. 

  417.         if (vorbis_tdtransform) {

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

  419.             return 1;

  420.         }

  421.     }

  422.     return 0;

  423. }

  424. 

  425. // Process floors part

  426. 

  427. static uint_fast8_t vorbis_floor0_decode(vorbis_context *vc,

  428.                                          vorbis_floor_data *vfu, float *vec);

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

  430. static uint_fast8_t vorbis_floor1_decode(vorbis_context *vc,

  431.                                          vorbis_floor_data *vfu, float *vec);

  432. static int vorbis_parse_setup_hdr_floors(vorbis_context *vc) {

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

  434.     uint_fast16_t i,j,k;

  435. 

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

  437. 

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

  439. 

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

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

  442. 

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

  444. 

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

  446. 

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

  448.             uint_fast8_t maximum_class=0;

  449.             uint_fast8_t rangebits;

  450.             uint_fast16_t floor1_values=2;

  451. 

  452.             floor_setup->decode=vorbis_floor1_decode;

  453. 

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

  455. 

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

  457. 

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

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

  460.                 if (floor_setup->data.t1.partition_class[j]>maximum_class) maximum_class=floor_setup->data.t1.partition_class[j];

  461. 

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

  463. 

  464.             }

  465. 

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

  467. 

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

  469. 

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

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

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

  473. 

  474.                 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]);

  475. 

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

  477.                     floor_setup->data.t1.class_masterbook[j]=get_bits(gb, 8);

  478. 

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

  480.                 }

  481. 

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

  483.                     floor_setup->data.t1.subclass_books[j][k]=(int16_t)get_bits(gb, 8)-1;

  484. 

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

  486.                 }

  487.             }

  488. 

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

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

  491. 

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

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

  494.             }

  495. 

  496.             floor_setup->data.t1.x_list=(uint_fast16_t *)av_mallocz(floor_setup->data.t1.x_list_dim * sizeof(uint_fast16_t));

  497.             floor_setup->data.t1.x_list_order=(uint_fast16_t *)av_mallocz(floor_setup->data.t1.x_list_dim * sizeof(uint_fast16_t));

  498.             floor_setup->data.t1.low_neighbour=(uint_fast16_t *)av_mallocz(floor_setup->data.t1.x_list_dim * sizeof(uint_fast16_t));

  499.             floor_setup->data.t1.high_neighbour=(uint_fast16_t *)av_mallocz(floor_setup->data.t1.x_list_dim * sizeof(uint_fast16_t));

  500. 

  501. 

  502.             rangebits=get_bits(gb, 4);

  503.             floor_setup->data.t1.x_list[0] = 0;

  504.             floor_setup->data.t1.x_list[1] = (1<<rangebits);

  505. 

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

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

  508.                     floor_setup->data.t1.x_list[floor1_values]=get_bits(gb, rangebits);

  509. 

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

  511.                 }

  512.             }

  513. 

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

  515. 

  516.             for(k=0;k<floor_setup->data.t1.x_list_dim;++k) {

  517.                 floor_setup->data.t1.x_list_order[k]=k;

  518.             }

  519. 

  520.             for(k=0;k<floor_setup->data.t1.x_list_dim-1;++k) {   // FIXME optimize sorting ?

  521.                 for(j=k+1;j<floor_setup->data.t1.x_list_dim;++j) {

  522.                     if(floor_setup->data.t1.x_list[floor_setup->data.t1.x_list_order[k]]>floor_setup->data.t1.x_list[floor_setup->data.t1.x_list_order[j]]) {

  523.                         uint_fast16_t tmp=floor_setup->data.t1.x_list_order[k];

  524.                         floor_setup->data.t1.x_list_order[k]=floor_setup->data.t1.x_list_order[j];

  525.                         floor_setup->data.t1.x_list_order[j]=tmp;

  526.                     }

  527.                 }

  528.             }

  529. 

  530. // Precalculate low and high neighbours

  531. 

  532.             for(k=2;k<floor_setup->data.t1.x_list_dim;++k) {

  533.                 floor_setup->data.t1.low_neighbour[k]=0;

  534.                 floor_setup->data.t1.high_neighbour[k]=1;  // correct according to SPEC requirements

  535. 

  536.                 for (j=0;j<k;++j) {

  537.                     if ((floor_setup->data.t1.x_list[j]<floor_setup->data.t1.x_list[k]) &&

  538.                       (floor_setup->data.t1.x_list[j]>floor_setup->data.t1.x_list[floor_setup->data.t1.low_neighbour[k]])) {

  539.                         floor_setup->data.t1.low_neighbour[k]=j;

  540.                     }

  541.                     if ((floor_setup->data.t1.x_list[j]>floor_setup->data.t1.x_list[k]) &&

  542.                       (floor_setup->data.t1.x_list[j]<floor_setup->data.t1.x_list[floor_setup->data.t1.high_neighbour[k]])) {

  543.                         floor_setup->data.t1.high_neighbour[k]=j;

  544.                     }

  545.                 }

  546.             }

  547.         }

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

  549.             uint_fast8_t max_codebook_dim=0;

  550. 

  551.             floor_setup->decode=vorbis_floor0_decode;

  552. 

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

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

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

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

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

  558.              * 2^0 - 1 == 0                             */

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

  560.               av_log(vc->avccontext, AV_LOG_ERROR,

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

  562.               return 1;

  563.             }

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

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

  566. 

  567.             /* allocate mem for booklist */

  568.             floor_setup->data.t0.book_list=

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

  570.             if(!floor_setup->data.t0.book_list) { return 1; }

  571.             /* read book indexes */

  572.             {

  573.                 int idx;

  574.                 uint_fast8_t book_idx;

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

  576.                     book_idx=get_bits(gb, 8);

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

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

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

  580. 

  581.                     if (floor_setup->data.t0.book_list[idx]>vc->codebook_count)

  582.                         return 1;

  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) { return 1; }

  596.             }

  597. 

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

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

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

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

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

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

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

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

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

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

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

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

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

  611.             {

  612.               int idx;

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

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

  615.                   idx+1,

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

  617.               }

  618.             }

  619. #endif

  620.         }

  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.     GetBitContext *gb=&vc->gb;

  633.     uint_fast8_t i, j, k;

  634. 

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

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

  637. 

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

  639. 

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

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

  642.         uint_fast8_t cascade[64];

  643.         uint_fast8_t high_bits;

  644.         uint_fast8_t low_bits;

  645. 

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

  647. 

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

  649. 

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

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

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

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

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

  655. 

  656.         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,

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

  658. 

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

  660.             high_bits=0;

  661.             low_bits=get_bits(gb, 3);

  662.             if (get_bits1(gb)) {

  663.                 high_bits=get_bits(gb, 5);

  664.             }

  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.                         res_setup->books[j][k]=get_bits(gb, 8);

  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.                     }

  681.                 } else {

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

  683.                 }

  684.             }

  685.         }

  686.     }

  687.     return 0;

  688. }

  689. 

  690. // Process mappings part

  691. 

  692. static int vorbis_parse_setup_hdr_mappings(vorbis_context *vc) {

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

  694.     uint_fast8_t i, j;

  695. 

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

  697.     vc->mappings=(vorbis_mapping *)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=(uint_fast8_t *)av_mallocz(mapping_setup->coupling_steps * sizeof(uint_fast8_t));

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

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

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

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

  721.                 // FIXME: sanity checks

  722.             }

  723.         } else {

  724.             mapping_setup->coupling_steps=0;

  725.         }

  726. 

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

  728. 

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

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

  731.             return 1; // following spec.

  732.         }

  733. 

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

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

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

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

  738.             }

  739.         }

  740. 

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

  742.             get_bits(gb, 8); // FIXME check?

  743.             mapping_setup->submap_floor[j]=get_bits(gb, 8);

  744.             mapping_setup->submap_residue[j]=get_bits(gb, 8);

  745. 

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

  747.         }

  748.     }

  749.     return 0;

  750. }

  751. 

  752. // Process modes part

  753. 

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

  755. {

  756.     vorbis_floor * floors=vc->floors;

  757.     vorbis_floor0 * vf;

  758.     int idx;

  759.     int_fast8_t blockflag;

  760.     int_fast32_t * map;

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

  762. 

  763.     for (blockflag=0;blockflag<2;++blockflag)

  764.     {

  765.     n=(blockflag ? vc->blocksize_1 : vc->blocksize_0) / 2;

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

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

  768. 

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

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

  771. 

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

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

  774.                               ((vf->bark_map_size)/

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

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

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

  778.         }

  779.     }

  780.     map[n]=-1;

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

  782.     }

  783. 

  784. #   ifdef V_DEBUG

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

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

  787.                  idx, map[idx]);

  788.     }

  789. #   endif

  790. }

  791. 

  792. static int vorbis_parse_setup_hdr_modes(vorbis_context *vc) {

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

  794.     uint_fast8_t i;

  795. 

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

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

  798. 

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

  800. 

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

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

  803. 

  804.         mode_setup->blockflag=get_bits(gb, 1);

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

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

  807.         mode_setup->mapping=get_bits(gb, 8); //FIXME check

  808. 

  809.         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);

  810.     }

  811.     return 0;

  812. }

  813. 

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

  815. 

  816. static int vorbis_parse_setup_hdr(vorbis_context *vc) {

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

  818. 

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

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

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

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

  823.         return 1;

  824.     }

  825. 

  826.     if (vorbis_parse_setup_hdr_codebooks(vc)) {

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

  828.         return 2;

  829.     }

  830.     if (vorbis_parse_setup_hdr_tdtransforms(vc)) {

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

  832.         return 3;

  833.     }

  834.     if (vorbis_parse_setup_hdr_floors(vc)) {

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

  836.         return 4;

  837.     }

  838.     if (vorbis_parse_setup_hdr_residues(vc)) {

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

  840.         return 5;

  841.     }

  842.     if (vorbis_parse_setup_hdr_mappings(vc)) {

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

  844.         return 6;

  845.     }

  846.     if (vorbis_parse_setup_hdr_modes(vc)) {

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

  848.         return 7;

  849.     }

  850.     if (!get_bits1(gb)) {

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

  852.         return 8; // framing flag bit unset error

  853.     }

  854. 

  855.     return 0;

  856. }

  857. 

  858. // Process the identification header

  859. 

  860. static int vorbis_parse_id_hdr(vorbis_context *vc){

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

  862.     uint_fast8_t bl0, bl1;

  863.     const float *vwin[8]={ vwin64, vwin128, vwin256, vwin512, vwin1024, vwin2048, vwin4096, vwin8192 };

  864. 

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

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

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

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

  869.         return 1;

  870.     }

  871. 

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

  873.     vc->audio_channels=get_bits(gb, 8);   //FIXME check >0

  874.     vc->audio_samplerate=get_bits_long_le(gb, 32);   //FIXME check >0

  875.     vc->bitrate_maximum=get_bits_long_le(gb, 32);

  876.     vc->bitrate_nominal=get_bits_long_le(gb, 32);

  877.     vc->bitrate_minimum=get_bits_long_le(gb, 32);

  878.     bl0=get_bits(gb, 4);

  879.     bl1=get_bits(gb, 4);

  880.     vc->blocksize_0=(1<<bl0);

  881.     vc->blocksize_1=(1<<bl1);

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

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

  884.         return 3;

  885.     }

  886.     // output format int16

  887.     if (vc->blocksize_1/2 * vc->audio_channels * 2 >

  888.                                              AVCODEC_MAX_AUDIO_FRAME_SIZE) {

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

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

  891.         return 4;

  892.     }

  893.     vc->swin=vwin[bl0-6];

  894.     vc->lwin=vwin[bl1-6];

  895. 

  896.     if(vc->exp_bias){

  897.         int i;

  898.         float *win;

  899.         win = av_malloc(vc->blocksize_0/2 * sizeof(float));

  900.         for(i=0; i<vc->blocksize_0/2; i++)

  901.             win[i] = vc->swin[i] * (1<<15);

  902.         vc->swin = win;

  903.         win = av_malloc(vc->blocksize_1/2 * sizeof(float));

  904.         for(i=0; i<vc->blocksize_1/2; i++)

  905.             win[i] = vc->lwin[i] * (1<<15);

  906.         vc->lwin = win;

  907.     }

  908. 

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

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

  911.         return 2;

  912.     }

  913. 

  914.     vc->channel_residues=(float *)av_malloc((vc->blocksize_1/2)*vc->audio_channels * sizeof(float));

  915.     vc->channel_floors=(float *)av_malloc((vc->blocksize_1/2)*vc->audio_channels * sizeof(float));

  916.     vc->saved=(float *)av_malloc((vc->blocksize_1/2)*vc->audio_channels * sizeof(float));

  917.     vc->ret=(float *)av_malloc((vc->blocksize_1/2)*vc->audio_channels * sizeof(float));

  918.     vc->buf=(float *)av_malloc(vc->blocksize_1 * sizeof(float));

  919.     vc->buf_tmp=(float *)av_malloc(vc->blocksize_1 * sizeof(float));

  920.     vc->saved_start=0;

  921. 

  922.     ff_mdct_init(&vc->mdct0, bl0, 1);

  923.     ff_mdct_init(&vc->mdct1, bl1, 1);

  924. 

  925.     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 ",

  926.             vc->version, vc->audio_channels, vc->audio_samplerate, vc->bitrate_maximum, vc->bitrate_nominal, vc->bitrate_minimum, vc->blocksize_0, vc->blocksize_1);

  927. 

  928. /*

  929.     BLK=vc->blocksize_0;

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

  931.         vc->swin[i]=sin(0.5*3.14159265358*(sin(((float)i+0.5)/(float)BLK*3.14159265358))*(sin(((float)i+0.5)/(float)BLK*3.14159265358)));

  932.     }

  933. */

  934. 

  935.     return 0;

  936. }

  937. 

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

  939. 

  940. static int vorbis_decode_init(AVCodecContext *avccontext) {

  941.     vorbis_context *vc = avccontext->priv_data ;

  942.     uint8_t *headers = avccontext->extradata;

  943.     int headers_len=avccontext->extradata_size;

  944.     uint8_t *header_start[3];

  945.     int header_len[3];

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

  947.     int i, j, hdr_type;

  948. 

  949.     vc->avccontext = avccontext;

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

  951. 

  952.     if(vc->dsp.float_to_int16 == ff_float_to_int16_c) {

  953.         vc->add_bias = 385;

  954.         vc->exp_bias = 0;

  955.     } else {

  956.         vc->add_bias = 0;

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

  958.     }

  959. 

  960.     if (!headers_len) {

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

  962.         return -1;

  963.     }

  964. 

  965.     if(headers[0] == 0 && headers[1] == 30) {

  966.         for(i = 0; i < 3; i++){

  967.             header_len[i] = *headers++ << 8;

  968.             header_len[i] += *headers++;

  969.             header_start[i] = headers;

  970.             headers += header_len[i];

  971.         }

  972.     } else if(headers[0] == 2) {

  973.         for(j=1,i=0;i<2;++i, ++j) {

  974.             header_len[i]=0;

  975.             while(j<headers_len && headers[j]==0xff) {

  976.                 header_len[i]+=0xff;

  977.                 ++j;

  978.             }

  979.             if (j>=headers_len) {

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

  981.                 return -1;

  982.             }

  983.             header_len[i]+=headers[j];

  984.         }

  985.         header_len[2]=headers_len-header_len[0]-header_len[1]-j;

  986.         headers+=j;

  987.         header_start[0] = headers;

  988.         header_start[1] = header_start[0] + header_len[0];

  989.         header_start[2] = header_start[1] + header_len[1];

  990.     } else {

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

  992.         return -1;

  993.     }

  994. 

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

  996.     hdr_type=get_bits(gb, 8);

  997.     if (hdr_type!=1) {

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

  999.         return -1;

  1000.     }

  1001.     if (vorbis_parse_id_hdr(vc)) {

  1002.         av_log(avccontext, AV_LOG_ERROR, "Id header corrupt.\n");

  1003.         vorbis_free(vc);

  1004.         return -1;

  1005.     }

  1006. 

  1007.     init_get_bits(gb, header_start[2], header_len[2]*8);

  1008.     hdr_type=get_bits(gb, 8);

  1009.     if (hdr_type!=5) {

  1010.         av_log(avccontext, AV_LOG_ERROR, "Third header is not the setup header.\n");

  1011.         return -1;

  1012.     }

  1013.     if (vorbis_parse_setup_hdr(vc)) {

  1014.         av_log(avccontext, AV_LOG_ERROR, "Setup header corrupt.\n");

  1015.         vorbis_free(vc);

  1016.         return -1;

  1017.     }

  1018. 

  1019.     avccontext->channels = vc->audio_channels;

  1020.     avccontext->sample_rate = vc->audio_samplerate;

  1021. 

  1022.     return 0 ;

  1023. }

  1024. 

  1025. // Decode audiopackets -------------------------------------------------

  1026. 

  1027. // Read and decode floor

  1028. 

  1029. static uint_fast8_t vorbis_floor0_decode(vorbis_context *vc,

  1030.                                          vorbis_floor_data *vfu, float *vec) {

  1031.     vorbis_floor0 * vf=&vfu->t0;

  1032.     float * lsp=vf->lsp;

  1033.     uint_fast32_t amplitude;

  1034.     uint_fast32_t book_idx;

  1035.     uint_fast8_t blockflag=vc->modes[vc->mode_number].blockflag;

  1036. 

  1037.     amplitude=get_bits(&vc->gb, vf->amplitude_bits);

  1038.     if (amplitude>0) {

  1039.         float last = 0;

  1040.         uint_fast16_t lsp_len = 0;

  1041.         uint_fast16_t idx;

  1042.         vorbis_codebook codebook;

  1043. 

  1044.         book_idx=get_bits(&vc->gb, ilog(vf->num_books));

  1045.         if ( book_idx >= vf->num_books ) {

  1046.             av_log( vc->avccontext, AV_LOG_ERROR,

  1047.                     "floor0 dec: booknumber too high!\n" );

  1048.             //FIXME: look above

  1049.         }

  1050.         AV_DEBUG( "floor0 dec: booknumber: %u\n", book_idx );

  1051.         codebook=vc->codebooks[vf->book_list[book_idx]];

  1052. 

  1053.         while (lsp_len<vf->order) {

  1054.             int vec_off;

  1055. 

  1056.             AV_DEBUG( "floor0 dec: book dimension: %d\n", codebook.dimensions );

  1057.             AV_DEBUG( "floor0 dec: maximum depth: %d\n", codebook.maxdepth );

  1058.             /* read temp vector */

  1059.             vec_off=get_vlc2(&vc->gb,

  1060.                              codebook.vlc.table,

  1061.                              codebook.nb_bits,

  1062.                              codebook.maxdepth ) *

  1063.                              codebook.dimensions;

  1064.             AV_DEBUG( "floor0 dec: vector offset: %d\n", vec_off );

  1065.             /* copy each vector component and add last to it */

  1066.             for (idx=0; idx<codebook.dimensions; ++idx) {

  1067.                 lsp[lsp_len+idx]=codebook.codevectors[vec_off+idx]+last;

  1068.             }

  1069.             last=lsp[lsp_len+idx-1]; /* set last to last vector component */

  1070. 

  1071.             lsp_len += codebook.dimensions;

  1072.         }

  1073. #ifdef V_DEBUG

  1074.         /* DEBUG: output lsp coeffs */

  1075.         {

  1076.             int idx;

  1077.             for ( idx = 0; idx < lsp_len; ++idx )

  1078.                 AV_DEBUG("floor0 dec: coeff at %d is %f\n", idx, lsp[idx] );

  1079.         }

  1080. #endif

  1081. 

  1082.         /* synthesize floor output vector */

  1083.         {

  1084.             int i;

  1085.             int order=vf->order;

  1086.             float wstep=M_PI/vf->bark_map_size;

  1087. 

  1088.             for(i=0;i<order;i++) { lsp[i]=2.0f*cos(lsp[i]); }

  1089. 

  1090.             AV_DEBUG("floor0 synth: map_size=%d; m=%d; wstep=%f\n",

  1091.                      vf->map_size, order, wstep);

  1092. 

  1093.             i=0;

  1094.             while(i<vf->map_size[blockflag]) {

  1095.                 int j, iter_cond=vf->map[blockflag][i];

  1096.                 float p=0.5f;

  1097.                 float q=0.5f;

  1098.                 float two_cos_w=2.0f*cos(wstep*iter_cond); // needed all times

  1099. 

  1100.                 /* similar part for the q and p products */

  1101.                 for(j=0;j<order;j+=2) {

  1102.                     q *= lsp[j]  -two_cos_w;

  1103.                     p *= lsp[j+1]-two_cos_w;

  1104.                 }

  1105.                 if(j==order) { // even order

  1106.                     p *= p*(2.0f-two_cos_w);

  1107.                     q *= q*(2.0f+two_cos_w);

  1108.                 }

  1109.                 else { // odd order

  1110.                     q *= two_cos_w-lsp[j]; // one more time for q

  1111. 

  1112.                     /* final step and square */

  1113.                     p *= p*(4.f-two_cos_w*two_cos_w);

  1114.                     q *= q;

  1115.                 }

  1116. 

  1117.                 /* calculate linear floor value */

  1118.                 {

  1119.                     q=exp( (

  1120.                              ( (amplitude*vf->amplitude_offset)/

  1121.                                (((1<<vf->amplitude_bits)-1) * sqrt(p+q)) )

  1122.                              - vf->amplitude_offset ) * .11512925f

  1123.                          );

  1124.                 }

  1125. 

  1126.                 /* fill vector */

  1127.                 do { vec[i]=q; ++i; }while(vf->map[blockflag][i]==iter_cond);

  1128.             }

  1129.         }

  1130.     }

  1131.     else {

  1132.         /* this channel is unused */

  1133.         return 1;

  1134.     }

  1135. 

  1136.     AV_DEBUG(" Floor0 decoded\n");

  1137. 

  1138.     return 0;

  1139. }

  1140. static uint_fast8_t vorbis_floor1_decode(vorbis_context *vc, vorbis_floor_data *vfu, float *vec) {

  1141.     vorbis_floor1 * vf=&vfu->t1;

  1142.     GetBitContext *gb=&vc->gb;

  1143.     uint_fast16_t range_v[4]={ 256, 128, 86, 64 };

  1144.     uint_fast16_t range=range_v[vf->multiplier-1];

  1145.     uint_fast16_t floor1_Y[vf->x_list_dim];

  1146.     uint_fast16_t floor1_Y_final[vf->x_list_dim];

  1147.     uint_fast8_t floor1_flag[vf->x_list_dim];

  1148.     uint_fast8_t class_;

  1149.     uint_fast8_t cdim;

  1150.     uint_fast8_t cbits;

  1151.     uint_fast8_t csub;

  1152.     uint_fast8_t cval;

  1153.     int_fast16_t book;

  1154.     uint_fast16_t offset;

  1155.     uint_fast16_t i,j;

  1156.     uint_fast16_t *floor_x_sort=vf->x_list_order;

  1157.     /*u*/int_fast16_t adx, ady, off, predicted; // WTF ? dy/adx= (unsigned)dy/adx ?

  1158.     int_fast16_t dy, err;

  1159.     uint_fast16_t lx,hx, ly, hy=0;

  1160. 

  1161. 

  1162.     if (!get_bits1(gb)) return 1; // silence

  1163. 

  1164. // Read values (or differences) for the floor's points

  1165. 

  1166.     floor1_Y[0]=get_bits(gb, ilog(range-1));

  1167.     floor1_Y[1]=get_bits(gb, ilog(range-1));

  1168. 

  1169.     AV_DEBUG("floor 0 Y %d floor 1 Y %d \n", floor1_Y[0], floor1_Y[1]);

  1170. 

  1171.     offset=2;

  1172.     for(i=0;i<vf->partitions;++i) {

  1173.         class_=vf->partition_class[i];

  1174.         cdim=vf->class_dimensions[class_];

  1175.         cbits=vf->class_subclasses[class_];

  1176.         csub=(1<<cbits)-1;

  1177.         cval=0;

  1178. 

  1179.         AV_DEBUG("Cbits %d \n", cbits);

  1180. 

  1181.         if (cbits) { // this reads all subclasses for this partition's class

  1182.             cval=get_vlc2(gb, vc->codebooks[vf->class_masterbook[class_]].vlc.table,

  1183.             vc->codebooks[vf->class_masterbook[class_]].nb_bits, 3);

  1184.         }

  1185. 

  1186.         for(j=0;j<cdim;++j) {

  1187.             book=vf->subclass_books[class_][cval & csub];

  1188. 

  1189.             AV_DEBUG("book %d Cbits %d cval %d  bits:%d \n", book, cbits, cval, get_bits_count(gb));

  1190. 

  1191.             cval=cval>>cbits;

  1192.             if (book>0) {

  1193.                 floor1_Y[offset+j]=get_vlc2(gb, vc->codebooks[book].vlc.table,

  1194.                 vc->codebooks[book].nb_bits, 3);

  1195.             } else {

  1196.                 floor1_Y[offset+j]=0;

  1197.             }

  1198. 

  1199.             AV_DEBUG(" floor(%d) = %d \n", vf->x_list[offset+j], floor1_Y[offset+j]);

  1200.         }

  1201.         offset+=cdim;

  1202.     }

  1203. 

  1204. // Amplitude calculation from the differences

  1205. 

  1206.     floor1_flag[0]=1;

  1207.     floor1_flag[1]=1;

  1208.     floor1_Y_final[0]=floor1_Y[0];

  1209.     floor1_Y_final[1]=floor1_Y[1];

  1210. 

  1211.     for(i=2;i<vf->x_list_dim;++i) {

  1212.         uint_fast16_t val, highroom, lowroom, room;

  1213.         uint_fast16_t high_neigh_offs;

  1214.         uint_fast16_t low_neigh_offs;

  1215. 

  1216.         low_neigh_offs=vf->low_neighbour[i];

  1217.         high_neigh_offs=vf->high_neighbour[i];

  1218.         dy=floor1_Y_final[high_neigh_offs]-floor1_Y_final[low_neigh_offs];  // render_point begin

  1219.         adx=vf->x_list[high_neigh_offs]-vf->x_list[low_neigh_offs];

  1220.         ady= ABS(dy);

  1221.         err=ady*(vf->x_list[i]-vf->x_list[low_neigh_offs]);

  1222.         off=(int16_t)err/(int16_t)adx;

  1223.         if (dy<0) {

  1224.             predicted=floor1_Y_final[low_neigh_offs]-off;

  1225.         } else {

  1226.             predicted=floor1_Y_final[low_neigh_offs]+off;

  1227.         } // render_point end

  1228. 

  1229.         val=floor1_Y[i];

  1230.         highroom=range-predicted;

  1231.         lowroom=predicted;

  1232.         if (highroom < lowroom) {

  1233.             room=highroom*2;

  1234.         } else {

  1235.             room=lowroom*2;   // SPEC mispelling

  1236.         }

  1237.         if (val) {

  1238.             floor1_flag[low_neigh_offs]=1;

  1239.             floor1_flag[high_neigh_offs]=1;

  1240.             floor1_flag[i]=1;

  1241.             if (val>=room) {

  1242.                 if (highroom > lowroom) {

  1243.                     floor1_Y_final[i]=val-lowroom+predicted;

  1244.                 } else {

  1245.                     floor1_Y_final[i]=predicted-val+highroom-1;

  1246.                 }

  1247.             } else {

  1248.                 if (val & 1) {

  1249.                     floor1_Y_final[i]=predicted-(val+1)/2;

  1250.                 } else {

  1251.                     floor1_Y_final[i]=predicted+val/2;

  1252.                 }

  1253.             }

  1254.         } else {

  1255.             floor1_flag[i]=0;

  1256.             floor1_Y_final[i]=predicted;

  1257.         }

  1258. 

  1259.         AV_DEBUG(" Decoded floor(%d) = %d / val %d \n", vf->x_list[i], floor1_Y_final[i], val);

  1260.     }

  1261. 

  1262. // Curve synth - connect the calculated dots and convert from dB scale FIXME optimize ?

  1263. 

  1264.     hx=0;

  1265.     lx=0;

  1266.     ly=floor1_Y_final[0]*vf->multiplier;  // conforms to SPEC

  1267. 

  1268.     vec[0]=floor1_inverse_db_table[ly];

  1269. 

  1270.     for(i=1;i<vf->x_list_dim;++i) {

  1271.         AV_DEBUG(" Looking at post %d \n", i);

  1272. 

  1273.         if (floor1_flag[floor_x_sort[i]]) {   // SPEC mispelled

  1274.             int_fast16_t x, y, dy, base, sy; // if uncommented: dy = -32 adx = 2  base = 2blablabla ?????

  1275. 

  1276.             hy=floor1_Y_final[floor_x_sort[i]]*vf->multiplier;

  1277.             hx=vf->x_list[floor_x_sort[i]];

  1278. 

  1279.             dy=hy-ly;

  1280.             adx=hx-lx;

  1281.             ady= (dy<0) ? -dy:dy;//ABS(dy);

  1282.             base=(int16_t)dy/(int16_t)adx;

  1283. 

  1284.             AV_DEBUG(" dy %d  adx %d base %d = %d \n", dy, adx, base, dy/adx);

  1285. 

  1286.             x=lx;

  1287.             y=ly;

  1288.             err=0;

  1289.             if (dy<0) {

  1290.                 sy=base-1;

  1291.             } else {

  1292.                 sy=base+1;

  1293.             }

  1294.             ady=ady-(base<0 ? -base : base)*adx;

  1295.             vec[x]=floor1_inverse_db_table[y];

  1296. 

  1297.             AV_DEBUG(" vec[ %d ] = %d \n", x, y);

  1298. 

  1299.             for(x=lx+1;(x<hx) && (x<vf->x_list[1]);++x) {

  1300.                 err+=ady;

  1301.                 if (err>=adx) {

  1302.                     err-=adx;

  1303.                     y+=sy;

  1304.                 } else {

  1305.                     y+=base;

  1306.                 }

  1307.                 vec[x]=floor1_inverse_db_table[y];

  1308. 

  1309.                 AV_DEBUG(" vec[ %d ] = %d \n", x, y);

  1310.             }

  1311. 

  1312. /*            for(j=1;j<hx-lx+1;++j) {  // iterating render_point

  1313.                 dy=hy-ly;

  1314.                 adx=hx-lx;

  1315.                 ady= dy<0 ? -dy : dy;

  1316.                 err=ady*j;

  1317.                 off=err/adx;

  1318.                 if (dy<0) {

  1319.                     predicted=ly-off;

  1320.                 } else {

  1321.                     predicted=ly+off;

  1322.                 }

  1323.                 if (lx+j < vf->x_list[1]) {

  1324.                     vec[lx+j]=floor1_inverse_db_table[predicted];

  1325.                 }

  1326.             }*/

  1327. 

  1328.             lx=hx;

  1329.             ly=hy;

  1330.         }

  1331.     }

  1332. 

  1333.     if (hx<vf->x_list[1]) {

  1334.         for(i=hx;i<vf->x_list[1];++i) {

  1335.             vec[i]=floor1_inverse_db_table[hy];

  1336.         }

  1337.     }

  1338. 

  1339.     AV_DEBUG(" Floor decoded\n");

  1340. 

  1341.     return 0;

  1342. }

  1343. 

  1344. // Read and decode residue

  1345. 

  1346. static int vorbis_residue_decode(vorbis_context *vc, vorbis_residue *vr, uint_fast8_t ch, uint_fast8_t *do_not_decode, float *vec, uint_fast16_t vlen) {

  1347.     GetBitContext *gb=&vc->gb;

  1348.     uint_fast8_t c_p_c=vc->codebooks[vr->classbook].dimensions;

  1349.     uint_fast16_t n_to_read=vr->end-vr->begin;

  1350.     uint_fast16_t ptns_to_read=n_to_read/vr->partition_size;

  1351.     uint_fast8_t classifs[ptns_to_read*vc->audio_channels];

  1352.     uint_fast8_t pass;

  1353.     uint_fast8_t ch_used;

  1354.     uint_fast8_t i,j,l;

  1355.     uint_fast16_t k;

  1356. 

  1357.     if (vr->type==2) {

  1358.         for(j=1;j<ch;++j) {

  1359.                 do_not_decode[0]&=do_not_decode[j];  // FIXME - clobbering input

  1360.         }

  1361.         if (do_not_decode[0]) return 0;

  1362.         ch_used=1;

  1363.     } else {

  1364.         ch_used=ch;

  1365.     }

  1366. 

  1367.     AV_DEBUG(" residue type 0/1/2 decode begin, ch: %d  cpc %d  \n", ch, c_p_c);

  1368. 

  1369.     for(pass=0;pass<=vr->maxpass;++pass) { // FIXME OPTIMIZE?

  1370.         uint_fast16_t voffset;

  1371.         uint_fast16_t partition_count;

  1372.         uint_fast16_t j_times_ptns_to_read;

  1373. 

  1374.         voffset=vr->begin;

  1375.         for(partition_count=0;partition_count<ptns_to_read;) {  // SPEC        error

  1376.             if (!pass) {

  1377.                 for(j_times_ptns_to_read=0, j=0;j<ch_used;++j) {

  1378.                     if (!do_not_decode[j]) {

  1379.                         uint_fast32_t temp=get_vlc2(gb, vc->codebooks[vr->classbook].vlc.table,

  1380.                         vc->codebooks[vr->classbook].nb_bits, 3);

  1381. 

  1382.                         AV_DEBUG("Classword: %d \n", temp);

  1383. 

  1384.                         assert(vr->classifications > 1 && temp<=65536); //needed for inverse[]

  1385.                         for(i=0;i<c_p_c;++i) {

  1386.                             uint_fast32_t temp2;

  1387. 

  1388.                             temp2=(((uint_fast64_t)temp) * inverse[vr->classifications])>>32;

  1389.                             if (partition_count+c_p_c-1-i < ptns_to_read) {

  1390.                                 classifs[j_times_ptns_to_read+partition_count+c_p_c-1-i]=temp-temp2*vr->classifications;

  1391.                             }

  1392.                             temp=temp2;

  1393.                         }

  1394.                     }

  1395.                     j_times_ptns_to_read+=ptns_to_read;

  1396.                 }

  1397.             }

  1398.             for(i=0;(i<c_p_c) && (partition_count<ptns_to_read);++i) {

  1399.                 for(j_times_ptns_to_read=0, j=0;j<ch_used;++j) {

  1400.                     uint_fast16_t voffs;

  1401. 

  1402.                     if (!do_not_decode[j]) {

  1403.                         uint_fast8_t vqclass=classifs[j_times_ptns_to_read+partition_count];

  1404.                         int_fast16_t vqbook=vr->books[vqclass][pass];

  1405. 

  1406.                         if (vqbook>=0) {

  1407.                             uint_fast16_t coffs;

  1408.                             uint_fast8_t dim= vc->codebooks[vqbook].dimensions;

  1409.                             uint_fast16_t step= dim==1 ? vr->partition_size

  1410.                                               : FASTDIV(vr->partition_size, dim);

  1411.                             vorbis_codebook codebook= vc->codebooks[vqbook];

  1412. 

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

  1414. 

  1415.                                 voffs=voffset+j*vlen;

  1416.                                 for(k=0;k<step;++k) {

  1417.                                     coffs=get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * codebook.dimensions;

  1418.                                     for(l=0;l<codebook.dimensions;++l) {

  1419.                                         vec[voffs+k+l*step]+=codebook.codevectors[coffs+l];  // FPMATH

  1420.                                     }

  1421.                                 }

  1422.                             }

  1423.                             else if (vr->type==1) {

  1424.                                 voffs=voffset+j*vlen;

  1425.                                 for(k=0;k<step;++k) {

  1426.                                     coffs=get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * codebook.dimensions;

  1427.                                     for(l=0;l<codebook.dimensions;++l, ++voffs) {

  1428.                                         vec[voffs]+=codebook.codevectors[coffs+l];  // FPMATH

  1429. 

  1430.                                         AV_DEBUG(" pass %d offs: %d curr: %f change: %f cv offs.: %d  \n", pass, voffs, vec[voffs], codebook.codevectors[coffs+l], coffs);

  1431.                                     }

  1432.                                 }

  1433.                             }

  1434.                             else if (vr->type==2 && ch==2 && (voffset&1)==0 && (codebook.dimensions&1)==0) { // most frequent case optimized

  1435.                                 voffs=voffset>>1;

  1436. 

  1437.                                 for(k=0;k<step;++k) {

  1438.                                     coffs=get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * codebook.dimensions;

  1439.                                     for(l=0;l<codebook.dimensions;l+=2, voffs++) {

  1440.                                         vec[voffs     ]+=codebook.codevectors[coffs+l  ];  // FPMATH

  1441.                                         vec[voffs+vlen]+=codebook.codevectors[coffs+l+1];  // FPMATH

  1442. 

  1443.                                         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);

  1444.                                     }

  1445.                                 }

  1446. 

  1447.                             }

  1448.                             else if (vr->type==2) {

  1449.                                 voffs=voffset;

  1450. 

  1451.                                 for(k=0;k<step;++k) {

  1452.                                     coffs=get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * codebook.dimensions;

  1453.                                     for(l=0;l<codebook.dimensions;++l, ++voffs) {

  1454.                                         vec[voffs/ch+(voffs%ch)*vlen]+=codebook.codevectors[coffs+l];  // FPMATH FIXME use if and counter instead of / and %

  1455. 

  1456.                                         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);

  1457.                                     }

  1458.                                 }

  1459.                             } else {

  1460.                                 av_log(vc->avccontext, AV_LOG_ERROR, " Invalid residue type while residue decode?! \n");

  1461.                                 return 1;

  1462.                             }

  1463.                         }

  1464.                     }

  1465.                     j_times_ptns_to_read+=ptns_to_read;

  1466.                 }

  1467.                 ++partition_count;

  1468.                 voffset+=vr->partition_size;

  1469.             }

  1470.         }

  1471.     }

  1472.     return 0;

  1473. }

  1474. 

  1475. void vorbis_inverse_coupling(float *mag, float *ang, int blocksize)

  1476. {

  1477.     int i;

  1478.     for(i=0; i<blocksize; i++)

  1479.     {

  1480.         if (mag[i]>0.0) {

  1481.             if (ang[i]>0.0) {

  1482.                 ang[i]=mag[i]-ang[i];

  1483.             } else {

  1484.                 float temp=ang[i];

  1485.                 ang[i]=mag[i];

  1486.                 mag[i]+=temp;

  1487.             }

  1488.         } else {

  1489.             if (ang[i]>0.0) {

  1490.                 ang[i]+=mag[i];

  1491.             } else {

  1492.                 float temp=ang[i];

  1493.                 ang[i]=mag[i];

  1494.                 mag[i]-=temp;

  1495.             }

  1496.         }

  1497.     }

  1498. }

  1499. 

  1500. // Decode the audio packet using the functions above

  1501. 

  1502. static int vorbis_parse_audio_packet(vorbis_context *vc) {

  1503.     GetBitContext *gb=&vc->gb;

  1504. 

  1505.     uint_fast8_t previous_window=0,next_window=0;

  1506.     uint_fast8_t mode_number;

  1507.     uint_fast16_t blocksize;

  1508.     int_fast32_t i,j;

  1509.     uint_fast8_t no_residue[vc->audio_channels];

  1510.     uint_fast8_t do_not_decode[vc->audio_channels];

  1511.     vorbis_mapping *mapping;

  1512.     float *ch_res_ptr=vc->channel_residues;

  1513.     float *ch_floor_ptr=vc->channel_floors;

  1514.     uint_fast8_t res_chan[vc->audio_channels];

  1515.     uint_fast8_t res_num=0;

  1516.     int_fast16_t retlen=0;

  1517.     uint_fast16_t saved_start=0;

  1518.     float fadd_bias = vc->add_bias;

  1519. 

  1520.     if (get_bits1(gb)) {

  1521.         av_log(vc->avccontext, AV_LOG_ERROR, "Not a Vorbis I audio packet.\n");

  1522.         return -1; // packet type not audio

  1523.     }

  1524. 

  1525.     if (vc->mode_count==1) {

  1526.         mode_number=0;

  1527.     } else {

  1528.         mode_number=get_bits(gb, ilog(vc->mode_count-1));

  1529.     }

  1530.     vc->mode_number=mode_number;

  1531.     mapping=&vc->mappings[vc->modes[mode_number].mapping];

  1532. 

  1533.     AV_DEBUG(" Mode number: %d , mapping: %d , blocktype %d \n", mode_number, vc->modes[mode_number].mapping, vc->modes[mode_number].blockflag);

  1534. 

  1535.     if (vc->modes[mode_number].blockflag) {

  1536.         previous_window=get_bits1(gb);

  1537.         next_window=get_bits1(gb);

  1538.     }

  1539. 

  1540.     blocksize=vc->modes[mode_number].blockflag ? vc->blocksize_1 : vc->blocksize_0;

  1541.     memset(ch_res_ptr, 0, sizeof(float)*vc->audio_channels*blocksize/2); //FIXME can this be removed ?

  1542.     memset(ch_floor_ptr, 0, sizeof(float)*vc->audio_channels*blocksize/2); //FIXME can this be removed ?

  1543. 

  1544. // Decode floor

  1545. 

  1546.     for(i=0;i<vc->audio_channels;++i) {

  1547.         vorbis_floor *floor;

  1548.         if (mapping->submaps>1) {

  1549.             floor=&vc->floors[mapping->submap_floor[mapping->mux[i]]];

  1550.         } else {

  1551.             floor=&vc->floors[mapping->submap_floor[0]];

  1552.         }

  1553. 

  1554.         no_residue[i]=floor->decode(vc, &floor->data, ch_floor_ptr);

  1555.         ch_floor_ptr+=blocksize/2;

  1556.     }

  1557. 

  1558. // Nonzero vector propagate

  1559. 

  1560.     for(i=mapping->coupling_steps-1;i>=0;--i) {

  1561.         if (!(no_residue[mapping->magnitude[i]] & no_residue[mapping->angle[i]])) {

  1562.             no_residue[mapping->magnitude[i]]=0;

  1563.             no_residue[mapping->angle[i]]=0;

  1564.         }

  1565.     }

  1566. 

  1567. // Decode residue

  1568. 

  1569.     for(i=0;i<mapping->submaps;++i) {

  1570.         vorbis_residue *residue;

  1571.         uint_fast8_t ch=0;

  1572. 

  1573.         for(j=0;j<vc->audio_channels;++j) {

  1574.             if ((mapping->submaps==1) || (i=mapping->mux[j])) {

  1575.                 res_chan[j]=res_num;

  1576.                 if (no_residue[j]) {

  1577.                     do_not_decode[ch]=1;

  1578.                 } else {

  1579.                     do_not_decode[ch]=0;

  1580.                 }

  1581.                 ++ch;

  1582.                 ++res_num;

  1583.             }

  1584.         }

  1585.         residue=&vc->residues[mapping->submap_residue[i]];

  1586.         vorbis_residue_decode(vc, residue, ch, do_not_decode, ch_res_ptr, blocksize/2);

  1587. 

  1588.         ch_res_ptr+=ch*blocksize/2;

  1589.     }

  1590. 

  1591. // Inverse coupling

  1592. 

  1593.     for(i=mapping->coupling_steps-1;i>=0;--i) { //warning: i has to be signed

  1594.         float *mag, *ang;

  1595. 

  1596.         mag=vc->channel_residues+res_chan[mapping->magnitude[i]]*blocksize/2;

  1597.         ang=vc->channel_residues+res_chan[mapping->angle[i]]*blocksize/2;

  1598.         vc->dsp.vorbis_inverse_coupling(mag, ang, blocksize/2);

  1599.     }

  1600. 

  1601. // Dotproduct

  1602. 

  1603.     for(j=0, ch_floor_ptr=vc->channel_floors;j<vc->audio_channels;++j,ch_floor_ptr+=blocksize/2) {

  1604.         ch_res_ptr=vc->channel_residues+res_chan[j]*blocksize/2;

  1605.         vc->dsp.vector_fmul(ch_floor_ptr, ch_res_ptr, blocksize/2);

  1606.     }

  1607. 

  1608. // MDCT, overlap/add, save data for next overlapping  FPMATH

  1609. 

  1610.     for(j=0;j<vc->audio_channels;++j) {

  1611.         uint_fast8_t step=vc->audio_channels;

  1612.         uint_fast16_t k;

  1613.         float *saved=vc->saved+j*vc->blocksize_1/2;

  1614.         float *ret=vc->ret;

  1615.         const float *lwin=vc->lwin;

  1616.         const float *swin=vc->swin;

  1617.         float *buf=vc->buf;

  1618.         float *buf_tmp=vc->buf_tmp;

  1619. 

  1620.         ch_floor_ptr=vc->channel_floors+j*blocksize/2;

  1621. 

  1622.         saved_start=vc->saved_start;

  1623. 

  1624.         vc->mdct0.fft.imdct_calc(vc->modes[mode_number].blockflag ? &vc->mdct1 : &vc->mdct0, buf, ch_floor_ptr, buf_tmp);

  1625. 

  1626.         //FIXME process channels together, to allow faster simd vector_fmul_add_add?

  1627.         if (vc->modes[mode_number].blockflag) {

  1628.             // -- overlap/add

  1629.             if (previous_window) {

  1630.                 vc->dsp.vector_fmul_add_add(ret+j, buf, lwin, saved, vc->add_bias, vc->blocksize_1/2, step);

  1631.                 retlen=vc->blocksize_1/2;

  1632.             } else {

  1633.                 int len = (vc->blocksize_1-vc->blocksize_0)/4;

  1634.                 buf += len;

  1635.                 vc->dsp.vector_fmul_add_add(ret+j, buf, swin, saved, vc->add_bias, vc->blocksize_0/2, step);

  1636.                 k = vc->blocksize_0/2*step + j;

  1637.                 buf += vc->blocksize_0/2;

  1638.                 if(vc->exp_bias){

  1639.                     for(i=0; i<len; i++, k+=step)

  1640.                         ((uint32_t*)ret)[k] = ((uint32_t*)buf)[i] + vc->exp_bias; // ret[k]=buf[i]*(1<<bias)

  1641.                 } else {

  1642.                     for(i=0; i<len; i++, k+=step)

  1643.                         ret[k] = buf[i] + fadd_bias;

  1644.                 }

  1645.                 buf=vc->buf;

  1646.                 retlen=vc->blocksize_0/2+len;

  1647.             }

  1648.             // -- save

  1649.             if (next_window) {

  1650.                 buf += vc->blocksize_1/2;

  1651.                 vc->dsp.vector_fmul_reverse(saved, buf, lwin, vc->blocksize_1/2);

  1652.                 saved_start=0;

  1653.             } else {

  1654.                 saved_start=(vc->blocksize_1-vc->blocksize_0)/4;

  1655.                 buf += vc->blocksize_1/2;

  1656.                 for(i=0; i<saved_start; i++)

  1657.                     ((uint32_t*)saved)[i] = ((uint32_t*)buf)[i] + vc->exp_bias;

  1658.                 vc->dsp.vector_fmul_reverse(saved+saved_start, buf+saved_start, swin, vc->blocksize_0/2);

  1659.             }

  1660.         } else {

  1661.             // --overlap/add

  1662.             if(vc->add_bias) {

  1663.                 for(k=j, i=0;i<saved_start;++i, k+=step)

  1664.                     ret[k] = saved[i] + fadd_bias;

  1665.             } else {

  1666.                 for(k=j, i=0;i<saved_start;++i, k+=step)

  1667.                     ret[k] = saved[i];

  1668.             }

  1669.             vc->dsp.vector_fmul_add_add(ret+k, buf, swin, saved+saved_start, vc->add_bias, vc->blocksize_0/2, step);

  1670.             retlen=saved_start+vc->blocksize_0/2;

  1671.             // -- save

  1672.             buf += vc->blocksize_0/2;

  1673.             vc->dsp.vector_fmul_reverse(saved, buf, swin, vc->blocksize_0/2);

  1674.             saved_start=0;

  1675.         }

  1676.     }

  1677.     vc->saved_start=saved_start;

  1678. 

  1679.     return retlen*vc->audio_channels;

  1680. }

  1681. 

  1682. // Return the decoded audio packet through the standard api

  1683. 

  1684. static int vorbis_decode_frame(AVCodecContext *avccontext,

  1685.                         void *data, int *data_size,

  1686.                         uint8_t *buf, int buf_size)

  1687. {

  1688.     vorbis_context *vc = avccontext->priv_data ;

  1689.     GetBitContext *gb = &(vc->gb);

  1690. 

  1691.     int_fast16_t i, len;

  1692. 

  1693.     if(!buf_size){

  1694.         return 0;

  1695.     }

  1696. 

  1697.     AV_DEBUG("packet length %d \n", buf_size);

  1698. 

  1699.     init_get_bits(gb, buf, buf_size*8);

  1700. 

  1701.     len=vorbis_parse_audio_packet(vc);

  1702. 

  1703.     if (len<=0) {

  1704.         *data_size=0;

  1705.         return buf_size;

  1706.     }

  1707. 

  1708.     if (!vc->first_frame) {

  1709.         vc->first_frame=1;

  1710.         *data_size=0;

  1711.         return buf_size ;

  1712.     }

  1713. 

  1714.     AV_DEBUG("parsed %d bytes %d bits, returned %d samples (*ch*bits) \n", get_bits_count(gb)/8, get_bits_count(gb)%8, len);

  1715. 

  1716.     vc->dsp.float_to_int16(data, vc->ret, len);

  1717.     *data_size=len*2;

  1718. 

  1719.     return buf_size ;

  1720. }

  1721. 

  1722. // Close decoder

  1723. 

  1724. static int vorbis_decode_close(AVCodecContext *avccontext) {

  1725.     vorbis_context *vc = avccontext->priv_data;

  1726. 

  1727.     vorbis_free(vc);

  1728. 

  1729.     return 0 ;

  1730. }

  1731. 

  1732. AVCodec vorbis_decoder = {

  1733.     "vorbis",

  1734.     CODEC_TYPE_AUDIO,

  1735.     CODEC_ID_VORBIS,

  1736.     sizeof(vorbis_context),

  1737.     vorbis_decode_init,

  1738.     NULL,

  1739.     vorbis_decode_close,

  1740.     vorbis_decode_frame,

  1741. };