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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. 

  24. #include <math.h>

  25. 

  26. #define ALT_BITSTREAM_READER_LE

  27. #include "avcodec.h"

  28. #include "bitstream.h"

  29. #include "dsputil.h"

  30. 

  31. #include "vorbis.h"

  32. 

  33. #define V_NB_BITS 8

  34. #define V_NB_BITS2 11

  35. #define V_MAX_VLCS (1<<16)

  36. 

  37. #ifndef V_DEBUG

  38. #define AV_DEBUG(...)

  39. #endif

  40. 

  41. #undef NDEBUG

  42. #include <assert.h>

  43. 

  44. /* Helper functions */

  45. 

  46. /**

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

  48.  */

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

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

  51.     else{

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

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

  54.     }

  55. }

  56. 

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

  58. 

  59. #define BARK(x) \

  60.     (13.1f*atan(0.00074f*(x))+2.24f*atan(1.85e-8f*(x)*(x))+1e-4f*(x))

  61. 

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

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

  64. 

  65.     do {

  66.         ++ret;

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

  68.     } while (j<=x);

  69. 

  70.     return (ret-1);

  71. }

  72. 

  73. static float vorbisfloat2float(uint_fast32_t val) {

  74.     double mant=val&0x1fffff;

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

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

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

  78. }

  79. 

  80. 

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

  82. 

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

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

  85.         0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};

  86. 

  87.     uint_fast8_t i,j;

  88.     uint_fast32_t code,p;

  89. 

  90. #ifdef V_DEBUG

  91.     GetBitContext gb;

  92. #endif

  93. 

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

  95.     if (p==num) {

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

  97.         return 0;

  98.     }

  99. 

  100.     codes[p]=0;

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

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

  103.     }

  104. 

  105. #ifdef V_DEBUG

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

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

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

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

  110.     }

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

  112. #endif

  113. 

  114.     ++p;

  115. 

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

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

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

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

  120.             if (exit_at_level[i]) break;

  121.         }

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

  123.         code=exit_at_level[i];

  124.         exit_at_level[i]=0;

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

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

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

  128.         }

  129.         codes[p]=code;

  130. 

  131. #ifdef V_DEBUG

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

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

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

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

  136.         }

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

  138. #endif

  139. 

  140.     }

  141. 

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

  143. 

  144.     return 0;

  145. }

  146. 

  147. // Free all allocated memory -----------------------------------------

  148. 

  149. static void vorbis_free(vorbis_context *vc) {

  150.     int_fast16_t i;

  151. 

  152.     av_freep(&vc->channel_residues);

  153.     av_freep(&vc->channel_floors);

  154.     av_freep(&vc->saved);

  155.     av_freep(&vc->ret);

  156.     av_freep(&vc->buf);

  157.     av_freep(&vc->buf_tmp);

  158. 

  159.     av_freep(&vc->residues);

  160.     av_freep(&vc->modes);

  161. 

  162.     ff_mdct_end(&vc->mdct0);

  163.     ff_mdct_end(&vc->mdct1);

  164. 

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

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

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

  168.     }

  169.     av_freep(&vc->codebooks);

  170. 

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

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

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

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

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

  176.         }

  177.         else {

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

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

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

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

  182.         }

  183.     }

  184.     av_freep(&vc->floors);

  185. 

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

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

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

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

  190.     }

  191.     av_freep(&vc->mappings);

  192. }

  193. 

  194. // Parse setup header -------------------------------------------------

  195. 

  196. // Process codebooks part

  197. 

  198. static int vorbis_parse_setup_hdr_codebooks(vorbis_context *vc) {

  199.     uint_fast16_t cb;

  200.     uint_fast8_t *tmp_vlc_bits;

  201.     uint_fast32_t *tmp_vlc_codes;

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

  203. 

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

  205. 

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

  207. 

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

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

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

  211. 

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

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

  214.         uint_fast8_t ordered;

  215.         uint_fast32_t t, used_entries=0;

  216.         uint_fast32_t entries;

  217. 

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

  219. 

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

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

  222.             goto error;

  223.         }

  224. 

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

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

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

  228.             goto error;

  229.         }

  230.         entries=get_bits(gb, 24);

  231.         if (entries>V_MAX_VLCS) {

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

  233.             goto error;

  234.         }

  235. 

  236.         ordered=get_bits1(gb);

  237. 

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

  239. 

  240.         if (!ordered) {

  241.             uint_fast16_t ce;

  242.             uint_fast8_t flag;

  243.             uint_fast8_t sparse=get_bits1(gb);

  244. 

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

  246. 

  247.             if (sparse) {

  248.                 AV_DEBUG(" sparse \n");

  249. 

  250.                 used_entries=0;

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

  252.                     flag=get_bits1(gb);

  253.                     if (flag) {

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

  255.                         ++used_entries;

  256.                     }

  257.                     else tmp_vlc_bits[ce]=0;

  258.                 }

  259.             } else {

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

  261. 

  262.                 used_entries=entries;

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

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

  265.                 }

  266.             }

  267.         } else {

  268.             uint_fast16_t current_entry=0;

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

  270. 

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

  272. 

  273.             used_entries=entries;

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

  275.                 uint_fast16_t i, number;

  276. 

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

  278. 

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

  280. 

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

  282. 

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

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

  285.                 }

  286. 

  287.                 current_entry+=number;

  288.             }

  289.             if (current_entry>used_entries) {

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

  291.                 goto error;

  292.             }

  293.         }

  294. 

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

  296. 

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

  298. 

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

  300. 

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

  302.             uint_fast16_t i, j, k;

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

  304.             uint_fast16_t codebook_multiplicands[codebook_lookup_values];

  305. 

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

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

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

  309.             uint_fast8_t codebook_sequence_p=get_bits1(gb);

  310. 

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

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

  313. 

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

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

  316. 

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

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

  319.             }

  320. 

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

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

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

  324.                 uint_fast8_t dim=codebook_setup->dimensions;

  325. 

  326.                 if (tmp_vlc_bits[i]) {

  327.                     float last=0.0;

  328.                     uint_fast32_t lookup_offset=i;

  329. 

  330. #ifdef V_DEBUG

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

  332. #endif

  333. 

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

  335.                         uint_fast32_t multiplicand_offset = lookup_offset % codebook_lookup_values;

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

  337.                         if (codebook_sequence_p) {

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

  339.                         }

  340.                         lookup_offset/=codebook_lookup_values;

  341.                     }

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

  343. 

  344. #ifdef V_DEBUG

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

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

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

  348.                     }

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

  350. #endif

  351. 

  352.                     ++j;

  353.                 }

  354.             }

  355.             if (j!=used_entries) {

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

  357.                 goto error;

  358.             }

  359.             entries=used_entries;

  360.         }

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

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

  363.             goto error;

  364.         }

  365. 

  366. // Initialize VLC table

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

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

  369.             goto error;

  370.         }

  371.         codebook_setup->maxdepth=0;

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

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

  374. 

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

  376.         else                                       codebook_setup->nb_bits=V_NB_BITS;

  377. 

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

  379. 

  380.         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)) {

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

  382.             goto error;

  383.         }

  384.     }

  385. 

  386.     av_free(tmp_vlc_bits);

  387.     av_free(tmp_vlc_codes);

  388.     return 0;

  389. 

  390. // Error:

  391. error:

  392.     av_free(tmp_vlc_bits);

  393.     av_free(tmp_vlc_codes);

  394.     return 1;

  395. }

  396. 

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

  398. 

  399. static int vorbis_parse_setup_hdr_tdtransforms(vorbis_context *vc) {

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

  401.     uint_fast8_t i;

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

  403. 

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

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

  406. 

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

  408. 

  409.         if (vorbis_tdtransform) {

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

  411.             return 1;

  412.         }

  413.     }

  414.     return 0;

  415. }

  416. 

  417. // Process floors part

  418. 

  419. static uint_fast8_t vorbis_floor0_decode(vorbis_context *vc,

  420.                                          vorbis_floor_data *vfu, float *vec);

  421. static uint_fast8_t vorbis_floor1_decode(vorbis_context *vc,

  422.                                          vorbis_floor_data *vfu, float *vec);

  423. static int vorbis_parse_setup_hdr_floors(vorbis_context *vc) {

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

  425.     uint_fast16_t i,j,k;

  426. 

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

  428. 

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

  430. 

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

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

  433. 

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

  435. 

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

  437. 

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

  439.             uint_fast8_t maximum_class=0;

  440.             uint_fast8_t rangebits;

  441.             uint_fast16_t floor1_values=2;

  442. 

  443.             floor_setup->decode=vorbis_floor1_decode;

  444. 

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

  446. 

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

  448. 

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

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

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

  452. 

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

  454. 

  455.             }

  456. 

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

  458. 

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

  460. 

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

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

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

  464. 

  465.                 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]);

  466. 

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

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

  469. 

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

  471.                 }

  472. 

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

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

  475. 

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

  477.                 }

  478.             }

  479. 

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

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

  482. 

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

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

  485.             }

  486. 

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

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

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

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

  491. 

  492. 

  493.             rangebits=get_bits(gb, 4);

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

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

  496. 

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

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

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

  500. 

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

  502.                 }

  503.             }

  504. 

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

  506. 

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

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

  509.             }

  510. 

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

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

  513.                     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]]) {

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

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

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

  517.                     }

  518.                 }

  519.             }

  520. 

  521. // Precalculate low and high neighbours

  522. 

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

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

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

  526. 

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

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

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

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

  531.                     }

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

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

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

  535.                     }

  536.                 }

  537.             }

  538.         }

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

  540.             uint_fast8_t max_codebook_dim=0;

  541. 

  542.             floor_setup->decode=vorbis_floor0_decode;

  543. 

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

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

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

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

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

  549.              * 2^0 - 1 == 0                             */

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

  551.               av_log(vc->avccontext, AV_LOG_ERROR,

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

  553.               return 1;

  554.             }

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

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

  557. 

  558.             /* allocate mem for booklist */

  559.             floor_setup->data.t0.book_list=

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

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

  562.             /* read book indexes */

  563.             {

  564.                 int idx;

  565.                 uint_fast8_t book_idx;

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

  567.                     book_idx=get_bits(gb, 8);

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

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

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

  571. 

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

  573.                         return 1;

  574.                 }

  575.             }

  576. 

  577.             /* allocate mem for lsp coefficients */

  578.             {

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

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

  581.                 floor_setup->data.t0.lsp=

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

  583.                               * sizeof(float));

  584.                 if(!floor_setup->data.t0.lsp) { return 1; }

  585.             }

  586. 

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

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

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

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

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

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

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

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

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

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

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

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

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

  600.             {

  601.               int idx;

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

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

  604.                   idx+1,

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

  606.               }

  607.             }

  608. #endif

  609.         }

  610.         else {

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

  612.             return 1;

  613.         }

  614.     }

  615.     return 0;

  616. }

  617. 

  618. // Process residues part

  619. 

  620. static int vorbis_parse_setup_hdr_residues(vorbis_context *vc){

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

  622.     uint_fast8_t i, j, k;

  623. 

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

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

  626. 

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

  628. 

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

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

  631.         uint_fast8_t cascade[64];

  632.         uint_fast8_t high_bits;

  633.         uint_fast8_t low_bits;

  634. 

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

  636. 

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

  638. 

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

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

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

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

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

  644. 

  645.         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,

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

  647. 

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

  649.             high_bits=0;

  650.             low_bits=get_bits(gb, 3);

  651.             if (get_bits1(gb)) {

  652.                 high_bits=get_bits(gb, 5);

  653.             }

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

  655. 

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

  657.         }

  658. 

  659.         res_setup->maxpass=0;

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

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

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

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

  664. 

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

  666. 

  667.                     if (k>res_setup->maxpass) {

  668.                         res_setup->maxpass=k;

  669.                     }

  670.                 } else {

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

  672.                 }

  673.             }

  674.         }

  675.     }

  676.     return 0;

  677. }

  678. 

  679. // Process mappings part

  680. 

  681. static int vorbis_parse_setup_hdr_mappings(vorbis_context *vc) {

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

  683.     uint_fast8_t i, j;

  684. 

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

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

  687. 

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

  689. 

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

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

  692. 

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

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

  695.             return 1;

  696.         }

  697.         if (get_bits1(gb)) {

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

  699.         } else {

  700.             mapping_setup->submaps=1;

  701.         }

  702. 

  703.         if (get_bits1(gb)) {

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

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

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

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

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

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

  710.                 // FIXME: sanity checks

  711.             }

  712.         } else {

  713.             mapping_setup->coupling_steps=0;

  714.         }

  715. 

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

  717. 

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

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

  720.             return 1; // following spec.

  721.         }

  722. 

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

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

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

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

  727.             }

  728.         }

  729. 

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

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

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

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

  734. 

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

  736.         }

  737.     }

  738.     return 0;

  739. }

  740. 

  741. // Process modes part

  742. 

  743. static void create_map( vorbis_context * vc, uint_fast8_t mode_number )

  744. {

  745.     vorbis_floor * floors=vc->floors;

  746.     vorbis_floor0 * vf;

  747.     int idx;

  748.     int_fast32_t * map;

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

  750. 

  751.     n=(vc->modes[mode_number].blockflag ?

  752.        vc->blocksize_1 : vc->blocksize_0) / 2;

  753.     floors[mode_number].data.t0.map=

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

  755. 

  756.     map=floors[mode_number].data.t0.map;

  757.     vf=&floors[mode_number].data.t0;

  758. 

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

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

  761.                               ((vf->bark_map_size)/

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

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

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

  765.         }

  766.     }

  767.     map[n]=-1;

  768.     vf->map_size=n;

  769. 

  770. #   ifdef V_DEBUG

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

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

  773.                  idx, map[idx]);

  774.     }

  775. #   endif

  776. }

  777. 

  778. static int vorbis_parse_setup_hdr_modes(vorbis_context *vc) {

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

  780.     uint_fast8_t i;

  781. 

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

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

  784. 

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

  786. 

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

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

  789. 

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

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

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

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

  794. 

  795.         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);

  796. 

  797.         if (vc->floors[i].floor_type == 0) { create_map( vc, i ); }

  798.     }

  799.     return 0;

  800. }

  801. 

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

  803. 

  804. static int vorbis_parse_setup_hdr(vorbis_context *vc) {

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

  806. 

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

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

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

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

  811.         return 1;

  812.     }

  813. 

  814.     if (vorbis_parse_setup_hdr_codebooks(vc)) {

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

  816.         return 2;

  817.     }

  818.     if (vorbis_parse_setup_hdr_tdtransforms(vc)) {

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

  820.         return 3;

  821.     }

  822.     if (vorbis_parse_setup_hdr_floors(vc)) {

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

  824.         return 4;

  825.     }

  826.     if (vorbis_parse_setup_hdr_residues(vc)) {

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

  828.         return 5;

  829.     }

  830.     if (vorbis_parse_setup_hdr_mappings(vc)) {

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

  832.         return 6;

  833.     }

  834.     if (vorbis_parse_setup_hdr_modes(vc)) {

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

  836.         return 7;

  837.     }

  838.     if (!get_bits1(gb)) {

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

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

  841.     }

  842. 

  843.     return 0;

  844. }

  845. 

  846. // Process the identification header

  847. 

  848. static int vorbis_parse_id_hdr(vorbis_context *vc){

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

  850.     uint_fast8_t bl0, bl1;

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

  852. 

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

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

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

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

  857.         return 1;

  858.     }

  859. 

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

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

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

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

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

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

  866.     bl0=get_bits(gb, 4);

  867.     bl1=get_bits(gb, 4);

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

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

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

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

  872.         return 3;

  873.     }

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

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

  876. 

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

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

  879.         return 2;

  880.     }

  881. 

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

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

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

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

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

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

  888.     vc->saved_start=0;

  889. 

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

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

  892. 

  893.     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 ",

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

  895. 

  896. /*

  897.     BLK=vc->blocksize_0;

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

  899.         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)));

  900.     }

  901. */

  902. 

  903.     return 0;

  904. }

  905. 

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

  907. 

  908. static int vorbis_decode_init(AVCodecContext *avccontext) {

  909.     vorbis_context *vc = avccontext->priv_data ;

  910.     uint8_t *headers = avccontext->extradata;

  911.     int headers_len=avccontext->extradata_size;

  912.     uint8_t *header_start[3];

  913.     int header_len[3];

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

  915.     int i, j, hdr_type;

  916. 

  917.     vc->avccontext = avccontext;

  918. 

  919.     if (!headers_len) {

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

  921.         return -1;

  922.     }

  923. 

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

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

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

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

  928.             header_start[i] = headers;

  929.             headers += header_len[i];

  930.         }

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

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

  933.             header_len[i]=0;

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

  935.                 header_len[i]+=0xff;

  936.                 ++j;

  937.             }

  938.             if (j>=headers_len) {

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

  940.                 return -1;

  941.             }

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

  943.         }

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

  945.         headers+=j;

  946.         header_start[0] = headers;

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

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

  949.     } else {

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

  951.         return -1;

  952.     }

  953. 

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

  955.     hdr_type=get_bits(gb, 8);

  956.     if (hdr_type!=1) {

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

  958.         return -1;

  959.     }

  960.     if (vorbis_parse_id_hdr(vc)) {

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

  962.         vorbis_free(vc);

  963.         return -1;

  964.     }

  965. 

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

  967.     hdr_type=get_bits(gb, 8);

  968.     if (hdr_type!=5) {

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

  970.         return -1;

  971.     }

  972.     if (vorbis_parse_setup_hdr(vc)) {

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

  974.         vorbis_free(vc);

  975.         return -1;

  976.     }

  977. 

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

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

  980. 

  981.     return 0 ;

  982. }

  983. 

  984. // Decode audiopackets -------------------------------------------------

  985. 

  986. // Read and decode floor

  987. 

  988. static uint_fast8_t vorbis_floor0_decode(vorbis_context *vc,

  989.                                          vorbis_floor_data *vfu, float *vec) {

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

  991.     float * lsp=vf->lsp;

  992.     uint_fast32_t amplitude;

  993.     uint_fast32_t book_idx;

  994. 

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

  996.     if (amplitude>0) {

  997.         float last = 0;

  998.         uint_fast16_t lsp_len = 0;

  999.         uint_fast16_t idx;

  1000.         vorbis_codebook codebook;

  1001. 

  1002.         book_idx=get_bits(&vc->gb, ilog(vf->num_books));

  1003.         if ( book_idx >= vf->num_books ) {

  1004.             av_log( vc->avccontext, AV_LOG_ERROR,

  1005.                     "floor0 dec: booknumber too high!\n" );

  1006.             //FIXME: look above

  1007.         }

  1008.         AV_DEBUG( "floor0 dec: booknumber: %u\n", book_idx );

  1009.         codebook=vc->codebooks[vf->book_list[book_idx]];

  1010. 

  1011.         while (lsp_len<vf->order) {

  1012.             int vec_off;

  1013. 

  1014.             AV_DEBUG( "floor0 dec: book dimension: %d\n", codebook.dimensions );

  1015.             AV_DEBUG( "floor0 dec: maximum depth: %d\n", codebook.maxdepth );

  1016.             /* read temp vector */

  1017.             vec_off=get_vlc2(&vc->gb,

  1018.                              codebook.vlc.table,

  1019.                              codebook.nb_bits,

  1020.                              codebook.maxdepth ) *

  1021.                              codebook.dimensions;

  1022.             AV_DEBUG( "floor0 dec: vector offset: %d\n", vec_off );

  1023.             /* copy each vector component and add last to it */

  1024.             for (idx=0; idx<codebook.dimensions; ++idx) {

  1025.                 lsp[lsp_len+idx]=codebook.codevectors[vec_off+idx]+last;

  1026.             }

  1027.             last=lsp[lsp_len+idx-1]; /* set last to last vector component */

  1028. 

  1029.             lsp_len += codebook.dimensions;

  1030.         }

  1031. #ifdef V_DEBUG

  1032.         /* DEBUG: output lsp coeffs */

  1033.         {

  1034.             int idx;

  1035.             for ( idx = 0; idx < lsp_len; ++idx )

  1036.                 AV_DEBUG("floor0 dec: coeff at %d is %f\n", idx, lsp[idx] );

  1037.         }

  1038. #endif

  1039. 

  1040.         /* synthesize floor output vector */

  1041.         {

  1042.             int i;

  1043.             int order=vf->order;

  1044.             float wstep=M_PI/vf->bark_map_size;

  1045. 

  1046.             for(i=0;i<order;i++) { lsp[i]=2.0f*cos(lsp[i]); }

  1047. 

  1048.             AV_DEBUG("floor0 synth: map_size=%d; m=%d; wstep=%f\n",

  1049.                      vf->map_size, order, wstep);

  1050. 

  1051.             i=0;

  1052.             while(i<vf->map_size) {

  1053.                 int j, iter_cond=vf->map[i];

  1054.                 float p=0.5f;

  1055.                 float q=0.5f;

  1056.                 float two_cos_w=2.0f*cos(wstep*iter_cond); // needed all times

  1057. 

  1058.                 /* similar part for the q and p products */

  1059.                 for(j=0;j<order;j+=2) {

  1060.                     q *= lsp[j]  -two_cos_w;

  1061.                     p *= lsp[j+1]-two_cos_w;

  1062.                 }

  1063.                 if(j==order) { // even order

  1064.                     p *= p*(2.0f-two_cos_w);

  1065.                     q *= q*(2.0f+two_cos_w);

  1066.                 }

  1067.                 else { // odd order

  1068.                     q *= two_cos_w-lsp[j]; // one more time for q

  1069. 

  1070.                     /* final step and square */

  1071.                     p *= p*(4.f-two_cos_w*two_cos_w);

  1072.                     q *= q;

  1073.                 }

  1074. 

  1075.                 /* calculate linear floor value */

  1076.                 {

  1077.                     q=exp( (

  1078.                              ( (amplitude*vf->amplitude_offset)/

  1079.                                (((1<<vf->amplitude_bits)-1) * sqrt(p+q)) )

  1080.                              - vf->amplitude_offset ) * .11512925f

  1081.                          );

  1082.                 }

  1083. 

  1084.                 /* fill vector */

  1085.                 do { vec[i]=q; ++i; }while(vf->map[i]==iter_cond);

  1086.             }

  1087.         }

  1088.     }

  1089.     else {

  1090.         /* this channel is unused */

  1091.         return 1;

  1092.     }

  1093. 

  1094.     AV_DEBUG(" Floor0 decoded\n");

  1095. 

  1096.     return 0;

  1097. }

  1098. static uint_fast8_t vorbis_floor1_decode(vorbis_context *vc, vorbis_floor_data *vfu, float *vec) {

  1099.     vorbis_floor1 * vf=&vfu->t1;

  1100.     GetBitContext *gb=&vc->gb;

  1101.     uint_fast16_t range_v[4]={ 256, 128, 86, 64 };

  1102.     uint_fast16_t range=range_v[vf->multiplier-1];

  1103.     uint_fast16_t floor1_Y[vf->x_list_dim];

  1104.     uint_fast16_t floor1_Y_final[vf->x_list_dim];

  1105.     uint_fast8_t floor1_flag[vf->x_list_dim];

  1106.     uint_fast8_t class_;

  1107.     uint_fast8_t cdim;

  1108.     uint_fast8_t cbits;

  1109.     uint_fast8_t csub;

  1110.     uint_fast8_t cval;

  1111.     int_fast16_t book;

  1112.     uint_fast16_t offset;

  1113.     uint_fast16_t i,j;

  1114.     uint_fast16_t *floor_x_sort=vf->x_list_order;

  1115.     /*u*/int_fast16_t adx, ady, off, predicted; // WTF ? dy/adx= (unsigned)dy/adx ?

  1116.     int_fast16_t dy, err;

  1117.     uint_fast16_t lx,hx, ly, hy=0;

  1118. 

  1119. 

  1120.     if (!get_bits1(gb)) return 1; // silence

  1121. 

  1122. // Read values (or differences) for the floor's points

  1123. 

  1124.     floor1_Y[0]=get_bits(gb, ilog(range-1));

  1125.     floor1_Y[1]=get_bits(gb, ilog(range-1));

  1126. 

  1127.     AV_DEBUG("floor 0 Y %d floor 1 Y %d \n", floor1_Y[0], floor1_Y[1]);

  1128. 

  1129.     offset=2;

  1130.     for(i=0;i<vf->partitions;++i) {

  1131.         class_=vf->partition_class[i];

  1132.         cdim=vf->class_dimensions[class_];

  1133.         cbits=vf->class_subclasses[class_];

  1134.         csub=(1<<cbits)-1;

  1135.         cval=0;

  1136. 

  1137.         AV_DEBUG("Cbits %d \n", cbits);

  1138. 

  1139.         if (cbits) { // this reads all subclasses for this partition's class

  1140.             cval=get_vlc2(gb, vc->codebooks[vf->class_masterbook[class_]].vlc.table,

  1141.             vc->codebooks[vf->class_masterbook[class_]].nb_bits, 3);

  1142.         }

  1143. 

  1144.         for(j=0;j<cdim;++j) {

  1145.             book=vf->subclass_books[class_][cval & csub];

  1146. 

  1147.             AV_DEBUG("book %d Cbits %d cval %d  bits:%d \n", book, cbits, cval, get_bits_count(gb));

  1148. 

  1149.             cval=cval>>cbits;

  1150.             if (book>0) {

  1151.                 floor1_Y[offset+j]=get_vlc2(gb, vc->codebooks[book].vlc.table,

  1152.                 vc->codebooks[book].nb_bits, 3);

  1153.             } else {

  1154.                 floor1_Y[offset+j]=0;

  1155.             }

  1156. 

  1157.             AV_DEBUG(" floor(%d) = %d \n", vf->x_list[offset+j], floor1_Y[offset+j]);

  1158.         }

  1159.         offset+=cdim;

  1160.     }

  1161. 

  1162. // Amplitude calculation from the differences

  1163. 

  1164.     floor1_flag[0]=1;

  1165.     floor1_flag[1]=1;

  1166.     floor1_Y_final[0]=floor1_Y[0];

  1167.     floor1_Y_final[1]=floor1_Y[1];

  1168. 

  1169.     for(i=2;i<vf->x_list_dim;++i) {

  1170.         uint_fast16_t val, highroom, lowroom, room;

  1171.         uint_fast16_t high_neigh_offs;

  1172.         uint_fast16_t low_neigh_offs;

  1173. 

  1174.         low_neigh_offs=vf->low_neighbour[i];

  1175.         high_neigh_offs=vf->high_neighbour[i];

  1176.         dy=floor1_Y_final[high_neigh_offs]-floor1_Y_final[low_neigh_offs];  // render_point begin

  1177.         adx=vf->x_list[high_neigh_offs]-vf->x_list[low_neigh_offs];

  1178.         ady= ABS(dy);

  1179.         err=ady*(vf->x_list[i]-vf->x_list[low_neigh_offs]);

  1180.         off=err/adx;

  1181.         if (dy<0) {

  1182.             predicted=floor1_Y_final[low_neigh_offs]-off;

  1183.         } else {

  1184.             predicted=floor1_Y_final[low_neigh_offs]+off;

  1185.         } // render_point end

  1186. 

  1187.         val=floor1_Y[i];

  1188.         highroom=range-predicted;

  1189.         lowroom=predicted;

  1190.         if (highroom < lowroom) {

  1191.             room=highroom*2;

  1192.         } else {

  1193.             room=lowroom*2;   // SPEC mispelling

  1194.         }

  1195.         if (val) {

  1196.             floor1_flag[low_neigh_offs]=1;

  1197.             floor1_flag[high_neigh_offs]=1;

  1198.             floor1_flag[i]=1;

  1199.             if (val>=room) {

  1200.                 if (highroom > lowroom) {

  1201.                     floor1_Y_final[i]=val-lowroom+predicted;

  1202.                 } else {

  1203.                     floor1_Y_final[i]=predicted-val+highroom-1;

  1204.                 }

  1205.             } else {

  1206.                 if (val & 1) {

  1207.                     floor1_Y_final[i]=predicted-(val+1)/2;

  1208.                 } else {

  1209.                     floor1_Y_final[i]=predicted+val/2;

  1210.                 }

  1211.             }

  1212.         } else {

  1213.             floor1_flag[i]=0;

  1214.             floor1_Y_final[i]=predicted;

  1215.         }

  1216. 

  1217.         AV_DEBUG(" Decoded floor(%d) = %d / val %d \n", vf->x_list[i], floor1_Y_final[i], val);

  1218.     }

  1219. 

  1220. // Curve synth - connect the calculated dots and convert from dB scale FIXME optimize ?

  1221. 

  1222.     hx=0;

  1223.     lx=0;

  1224.     ly=floor1_Y_final[0]*vf->multiplier;  // conforms to SPEC

  1225. 

  1226.     vec[0]=floor1_inverse_db_table[ly];

  1227. 

  1228.     for(i=1;i<vf->x_list_dim;++i) {

  1229.         AV_DEBUG(" Looking at post %d \n", i);

  1230. 

  1231.         if (floor1_flag[floor_x_sort[i]]) {   // SPEC mispelled

  1232.             int_fast16_t x, y, dy, base, sy; // if uncommented: dy = -32 adx = 2  base = 2blablabla ?????

  1233. 

  1234.             hy=floor1_Y_final[floor_x_sort[i]]*vf->multiplier;

  1235.             hx=vf->x_list[floor_x_sort[i]];

  1236. 

  1237.             dy=hy-ly;

  1238.             adx=hx-lx;

  1239.             ady= (dy<0) ? -dy:dy;//ABS(dy);

  1240.             base=dy/adx;

  1241. 

  1242.             AV_DEBUG(" dy %d  adx %d base %d = %d \n", dy, adx, base, dy/adx);

  1243. 

  1244.             x=lx;

  1245.             y=ly;

  1246.             err=0;

  1247.             if (dy<0) {

  1248.                 sy=base-1;

  1249.             } else {

  1250.                 sy=base+1;

  1251.             }

  1252.             ady=ady-(base<0 ? -base : base)*adx;

  1253.             vec[x]=floor1_inverse_db_table[y];

  1254. 

  1255.             AV_DEBUG(" vec[ %d ] = %d \n", x, y);

  1256. 

  1257.             for(x=lx+1;(x<hx) && (x<vf->x_list[1]);++x) {

  1258.                 err+=ady;

  1259.                 if (err>=adx) {

  1260.                     err-=adx;

  1261.                     y+=sy;

  1262.                 } else {

  1263.                     y+=base;

  1264.                 }

  1265.                 vec[x]=floor1_inverse_db_table[y];

  1266. 

  1267.                 AV_DEBUG(" vec[ %d ] = %d \n", x, y);

  1268.             }

  1269. 

  1270. /*            for(j=1;j<hx-lx+1;++j) {  // iterating render_point

  1271.                 dy=hy-ly;

  1272.                 adx=hx-lx;

  1273.                 ady= dy<0 ? -dy : dy;

  1274.                 err=ady*j;

  1275.                 off=err/adx;

  1276.                 if (dy<0) {

  1277.                     predicted=ly-off;

  1278.                 } else {

  1279.                     predicted=ly+off;

  1280.                 }

  1281.                 if (lx+j < vf->x_list[1]) {

  1282.                     vec[lx+j]=floor1_inverse_db_table[predicted];

  1283.                 }

  1284.             }*/

  1285. 

  1286.             lx=hx;

  1287.             ly=hy;

  1288.         }

  1289.     }

  1290. 

  1291.     if (hx<vf->x_list[1]) {

  1292.         for(i=hx;i<vf->x_list[1];++i) {

  1293.             vec[i]=floor1_inverse_db_table[hy];

  1294.         }

  1295.     }

  1296. 

  1297.     AV_DEBUG(" Floor decoded\n");

  1298. 

  1299.     return 0;

  1300. }

  1301. 

  1302. // Read and decode residue

  1303. 

  1304. 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) {

  1305.     GetBitContext *gb=&vc->gb;

  1306.     uint_fast8_t c_p_c=vc->codebooks[vr->classbook].dimensions;

  1307.     uint_fast16_t n_to_read=vr->end-vr->begin;

  1308.     uint_fast16_t ptns_to_read=n_to_read/vr->partition_size;

  1309.     uint_fast8_t classifs[ptns_to_read*vc->audio_channels];

  1310.     uint_fast8_t pass;

  1311.     uint_fast8_t ch_used;

  1312.     uint_fast8_t i,j,l;

  1313.     uint_fast16_t k;

  1314. 

  1315.     if (vr->type==2) {

  1316.         for(j=1;j<ch;++j) {

  1317.                 do_not_decode[0]&=do_not_decode[j];  // FIXME - clobbering input

  1318.         }

  1319.         if (do_not_decode[0]) return 0;

  1320.         ch_used=1;

  1321.     } else {

  1322.         ch_used=ch;

  1323.     }

  1324. 

  1325.     AV_DEBUG(" residue type 0/1/2 decode begin, ch: %d  cpc %d  \n", ch, c_p_c);

  1326. 

  1327.     for(pass=0;pass<=vr->maxpass;++pass) { // FIXME OPTIMIZE?

  1328.         uint_fast16_t voffset;

  1329.         uint_fast16_t partition_count;

  1330.         uint_fast16_t j_times_ptns_to_read;

  1331. 

  1332.         voffset=vr->begin;

  1333.         for(partition_count=0;partition_count<ptns_to_read;) {  // SPEC        error

  1334.             if (!pass) {

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

  1336.                     if (!do_not_decode[j]) {

  1337.                         uint_fast32_t temp=get_vlc2(gb, vc->codebooks[vr->classbook].vlc.table,

  1338.                         vc->codebooks[vr->classbook].nb_bits, 3);

  1339. 

  1340.                         AV_DEBUG("Classword: %d \n", temp);

  1341. 

  1342.                         assert(vr->classifications > 1 && vr->classifications<256 && temp<=65536); //needed for inverse[]

  1343.                         for(i=0;i<c_p_c;++i) {

  1344.                             uint_fast32_t temp2;

  1345. 

  1346.                             temp2=(((uint_fast64_t)temp) * inverse[vr->classifications])>>32;

  1347.                             classifs[j_times_ptns_to_read+partition_count+c_p_c-1-i]=temp-temp2*vr->classifications;

  1348.                             temp=temp2;

  1349.                         }

  1350.                     }

  1351.                     j_times_ptns_to_read+=ptns_to_read;

  1352.                 }

  1353.             }

  1354.             for(i=0;(i<c_p_c) && (partition_count<ptns_to_read);++i) {

  1355.                 for(j_times_ptns_to_read=0, j=0;j<ch_used;++j) {

  1356.                     uint_fast16_t voffs;

  1357. 

  1358.                     if (!do_not_decode[j]) {

  1359.                         uint_fast8_t vqclass=classifs[j_times_ptns_to_read+partition_count];

  1360.                         int_fast16_t vqbook=vr->books[vqclass][pass];

  1361. 

  1362.                         if (vqbook>=0) {

  1363.                             uint_fast16_t coffs;

  1364.                             uint_fast16_t step=vr->partition_size/vc->codebooks[vqbook].dimensions;

  1365.                             vorbis_codebook codebook= vc->codebooks[vqbook];

  1366. 

  1367.                             if (vr->type==0) {

  1368. 

  1369.                                 voffs=voffset+j*vlen;

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

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

  1372.                                     for(l=0;l<codebook.dimensions;++l) {

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

  1374.                                     }

  1375.                                 }

  1376.                             }

  1377.                             else if (vr->type==1) {

  1378.                                 voffs=voffset+j*vlen;

  1379.                                 for(k=0;k<step;++k) {

  1380.                                     coffs=get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * codebook.dimensions;

  1381.                                     for(l=0;l<codebook.dimensions;++l, ++voffs) {

  1382.                                         vec[voffs]+=codebook.codevectors[coffs+l];  // FPMATH

  1383. 

  1384.                                         AV_DEBUG(" pass %d offs: %d curr: %f change: %f cv offs.: %d  \n", pass, voffs, vec[voffs], codebook.codevectors[coffs+l], coffs);

  1385.                                     }

  1386.                                 }

  1387.                             }

  1388.                             else if (vr->type==2 && ch==2 && (voffset&1)==0 && (codebook.dimensions&1)==0) { // most frequent case optimized

  1389.                                 voffs=voffset>>1;

  1390. 

  1391.                                 for(k=0;k<step;++k) {

  1392.                                     coffs=get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * codebook.dimensions;

  1393.                                     for(l=0;l<codebook.dimensions;l+=2, voffs++) {

  1394.                                         vec[voffs     ]+=codebook.codevectors[coffs+l  ];  // FPMATH

  1395.                                         vec[voffs+vlen]+=codebook.codevectors[coffs+l+1];  // FPMATH

  1396. 

  1397.                                         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);

  1398.                                     }

  1399.                                 }

  1400. 

  1401.                             }

  1402.                             else if (vr->type==2) {

  1403.                                 voffs=voffset;

  1404. 

  1405.                                 for(k=0;k<step;++k) {

  1406.                                     coffs=get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * codebook.dimensions;

  1407.                                     for(l=0;l<codebook.dimensions;++l, ++voffs) {

  1408.                                         vec[voffs/ch+(voffs%ch)*vlen]+=codebook.codevectors[coffs+l];  // FPMATH FIXME use if and counter instead of / and %

  1409. 

  1410.                                         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);

  1411.                                     }

  1412.                                 }

  1413.                             } else {

  1414.                                 av_log(vc->avccontext, AV_LOG_ERROR, " Invalid residue type while residue decode?! \n");

  1415.                                 return 1;

  1416.                             }

  1417.                         }

  1418.                     }

  1419.                     j_times_ptns_to_read+=ptns_to_read;

  1420.                 }

  1421.                 ++partition_count;

  1422.                 voffset+=vr->partition_size;

  1423.             }

  1424.         }

  1425.     }

  1426.     return 0;

  1427. }

  1428. 

  1429. // Decode the audio packet using the functions above

  1430. #define BIAS 385

  1431. 

  1432. static int vorbis_parse_audio_packet(vorbis_context *vc) {

  1433.     GetBitContext *gb=&vc->gb;

  1434. 

  1435.     uint_fast8_t previous_window=0,next_window=0;

  1436.     uint_fast8_t mode_number;

  1437.     uint_fast16_t blocksize;

  1438.     int_fast32_t i,j;

  1439.     uint_fast8_t no_residue[vc->audio_channels];

  1440.     uint_fast8_t do_not_decode[vc->audio_channels];

  1441.     vorbis_mapping *mapping;

  1442.     float *ch_res_ptr=vc->channel_residues;

  1443.     float *ch_floor_ptr=vc->channel_floors;

  1444.     uint_fast8_t res_chan[vc->audio_channels];

  1445.     uint_fast8_t res_num=0;

  1446.     int_fast16_t retlen=0;

  1447.     uint_fast16_t saved_start=0;

  1448. 

  1449.     if (get_bits1(gb)) {

  1450.         av_log(vc->avccontext, AV_LOG_ERROR, "Not a Vorbis I audio packet.\n");

  1451.         return -1; // packet type not audio

  1452.     }

  1453. 

  1454.     if (vc->mode_count==1) {

  1455.         mode_number=0;

  1456.     } else {

  1457.         mode_number=get_bits(gb, ilog(vc->mode_count-1));

  1458.     }

  1459.     mapping=&vc->mappings[vc->modes[mode_number].mapping];

  1460. 

  1461.     AV_DEBUG(" Mode number: %d , mapping: %d , blocktype %d \n", mode_number, vc->modes[mode_number].mapping, vc->modes[mode_number].blockflag);

  1462. 

  1463.     if (vc->modes[mode_number].blockflag) {

  1464.         previous_window=get_bits1(gb);

  1465.         next_window=get_bits1(gb);

  1466.     }

  1467. 

  1468.     blocksize=vc->modes[mode_number].blockflag ? vc->blocksize_1 : vc->blocksize_0;

  1469.     memset(ch_res_ptr, 0, sizeof(float)*vc->audio_channels*blocksize/2); //FIXME can this be removed ?

  1470.     memset(ch_floor_ptr, 0, sizeof(float)*vc->audio_channels*blocksize/2); //FIXME can this be removed ?

  1471. 

  1472. // Decode floor

  1473. 

  1474.     for(i=0;i<vc->audio_channels;++i) {

  1475.         vorbis_floor *floor;

  1476.         if (mapping->submaps>1) {

  1477.             floor=&vc->floors[mapping->submap_floor[mapping->mux[i]]];

  1478.         } else {

  1479.             floor=&vc->floors[mapping->submap_floor[0]];

  1480.         }

  1481. 

  1482.         no_residue[i]=floor->decode(vc, &floor->data, ch_floor_ptr);

  1483.         ch_floor_ptr+=blocksize/2;

  1484.     }

  1485. 

  1486. // Nonzero vector propagate

  1487. 

  1488.     for(i=mapping->coupling_steps-1;i>=0;--i) {

  1489.         if (!(no_residue[mapping->magnitude[i]] & no_residue[mapping->angle[i]])) {

  1490.             no_residue[mapping->magnitude[i]]=0;

  1491.             no_residue[mapping->angle[i]]=0;

  1492.         }

  1493.     }

  1494. 

  1495. // Decode residue

  1496. 

  1497.     for(i=0;i<mapping->submaps;++i) {

  1498.         vorbis_residue *residue;

  1499.         uint_fast8_t ch=0;

  1500. 

  1501.         for(j=0;j<vc->audio_channels;++j) {

  1502.             if ((mapping->submaps==1) || (i=mapping->mux[j])) {

  1503.                 res_chan[j]=res_num;

  1504.                 if (no_residue[j]) {

  1505.                     do_not_decode[ch]=1;

  1506.                 } else {

  1507.                     do_not_decode[ch]=0;

  1508.                 }

  1509.                 ++ch;

  1510.                 ++res_num;

  1511.             }

  1512.         }

  1513.         residue=&vc->residues[mapping->submap_residue[i]];

  1514.         vorbis_residue_decode(vc, residue, ch, do_not_decode, ch_res_ptr, blocksize/2);

  1515. 

  1516.         ch_res_ptr+=ch*blocksize/2;

  1517.     }

  1518. 

  1519. // Inverse coupling

  1520. 

  1521.     for(i=mapping->coupling_steps-1;i>=0;--i) { //warning: i has to be signed

  1522.         float *mag, *ang;

  1523. 

  1524.         mag=vc->channel_residues+res_chan[mapping->magnitude[i]]*blocksize/2;

  1525.         ang=vc->channel_residues+res_chan[mapping->angle[i]]*blocksize/2;

  1526.         for(j=0;j<blocksize/2;++j) {

  1527.             float temp;

  1528.             if (mag[j]>0.0) {

  1529.                 if (ang[j]>0.0) {

  1530.                     ang[j]=mag[j]-ang[j];

  1531.                 } else {

  1532.                     temp=ang[j];

  1533.                     ang[j]=mag[j];

  1534.                     mag[j]+=temp;

  1535.                 }

  1536.             } else {

  1537.                 if (ang[j]>0.0) {

  1538.                     ang[j]+=mag[j];

  1539.                 } else {

  1540.                     temp=ang[j];

  1541.                     ang[j]=mag[j];

  1542.                     mag[j]-=temp;

  1543.                 }

  1544.             }

  1545.         }

  1546.     }

  1547. 

  1548. // Dotproduct

  1549. 

  1550.     for(j=0, ch_floor_ptr=vc->channel_floors;j<vc->audio_channels;++j,ch_floor_ptr+=blocksize/2) {

  1551.         ch_res_ptr=vc->channel_residues+res_chan[j]*blocksize/2;

  1552. 

  1553.         for(i=0;i<blocksize/2;++i) {

  1554.             ch_floor_ptr[i]*=ch_res_ptr[i]; //FPMATH

  1555.         }

  1556.     }

  1557. 

  1558. // MDCT, overlap/add, save data for next overlapping  FPMATH

  1559. 

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

  1561.         uint_fast8_t step=vc->audio_channels;

  1562.         uint_fast16_t k;

  1563.         float *saved=vc->saved+j*vc->blocksize_1/2;

  1564.         float *ret=vc->ret;

  1565.         const float *lwin=vc->lwin;

  1566.         const float *swin=vc->swin;

  1567.         float *buf=vc->buf;

  1568.         float *buf_tmp=vc->buf_tmp;

  1569. 

  1570.         ch_floor_ptr=vc->channel_floors+j*blocksize/2;

  1571. 

  1572.         saved_start=vc->saved_start;

  1573. 

  1574.         ff_imdct_calc(vc->modes[mode_number].blockflag ? &vc->mdct1 : &vc->mdct0, buf, ch_floor_ptr, buf_tmp);

  1575. 

  1576.         if (vc->modes[mode_number].blockflag) {

  1577.             // -- overlap/add

  1578.             if (previous_window) {

  1579.                 for(k=j, i=0;i<vc->blocksize_1/2;++i, k+=step) {

  1580.                     ret[k]=saved[i]+buf[i]*lwin[i]+BIAS;

  1581.                 }

  1582.                 retlen=vc->blocksize_1/2;

  1583.             } else {

  1584.                 buf += (vc->blocksize_1-vc->blocksize_0)/4;

  1585.                 for(k=j, i=0;i<vc->blocksize_0/2;++i, k+=step) {

  1586.                     ret[k]=saved[i]+buf[i]*swin[i]+BIAS;

  1587.                 }

  1588.                 buf += vc->blocksize_0/2;

  1589.                 for(i=0;i<(vc->blocksize_1-vc->blocksize_0)/4;++i, k+=step) {

  1590.                     ret[k]=buf[i]+BIAS;

  1591.                 }

  1592.                 buf=vc->buf;

  1593.                 retlen=vc->blocksize_0/2+(vc->blocksize_1-vc->blocksize_0)/4;

  1594.             }

  1595.             // -- save

  1596.             if (next_window) {

  1597.                 buf += vc->blocksize_1/2;

  1598.                 lwin += vc->blocksize_1/2-1;

  1599.                 for(i=0;i<vc->blocksize_1/2;++i) {

  1600.                     saved[i]=buf[i]*lwin[-i];

  1601.                 }

  1602.                 saved_start=0;

  1603.             } else {

  1604.                 saved_start=(vc->blocksize_1-vc->blocksize_0)/4;

  1605.                 buf += vc->blocksize_1/2;

  1606.                 for(i=0;i<saved_start;++i) {

  1607.                     saved[i]=buf[i];

  1608.                 }

  1609.                 swin += vc->blocksize_0/2-1;

  1610.                 for(i=0;i<vc->blocksize_0/2;++i) {

  1611.                     saved[saved_start+i]=buf[saved_start+i]*swin[-i];

  1612.                 }

  1613.             }

  1614.         } else {

  1615.             // --overlap/add

  1616.             for(k=j, i=0;i<saved_start;++i, k+=step) {

  1617.                 ret[k]=saved[i]+BIAS;

  1618.             }

  1619.             for(i=0;i<vc->blocksize_0/2;++i, k+=step) {

  1620.                 ret[k]=saved[saved_start+i]+buf[i]*swin[i]+BIAS;

  1621.             }

  1622.             retlen=saved_start+vc->blocksize_0/2;

  1623.             // -- save

  1624.             buf += vc->blocksize_0/2;

  1625.             swin += vc->blocksize_0/2-1;

  1626.             for(i=0;i<vc->blocksize_0/2;++i) {

  1627.                 saved[i]=buf[i]*swin[-i];

  1628.             }

  1629.             saved_start=0;

  1630.         }

  1631.     }

  1632.     vc->saved_start=saved_start;

  1633. 

  1634.     return retlen*vc->audio_channels;

  1635. }

  1636. 

  1637. // Return the decoded audio packet through the standard api

  1638. 

  1639. static int vorbis_decode_frame(AVCodecContext *avccontext,

  1640.                         void *data, int *data_size,

  1641.                         uint8_t *buf, int buf_size)

  1642. {

  1643.     vorbis_context *vc = avccontext->priv_data ;

  1644.     GetBitContext *gb = &(vc->gb);

  1645. 

  1646.     int_fast16_t i, len;

  1647. 

  1648.     if(!buf_size){

  1649.         return 0;

  1650.     }

  1651. 

  1652.     AV_DEBUG("packet length %d \n", buf_size);

  1653. 

  1654.     init_get_bits(gb, buf, buf_size*8);

  1655. 

  1656.     len=vorbis_parse_audio_packet(vc);

  1657. 

  1658.     if (len<=0) {

  1659.         *data_size=0;

  1660.         return buf_size;

  1661.     }

  1662. 

  1663.     if (!vc->first_frame) {

  1664.         vc->first_frame=1;

  1665.         *data_size=0;

  1666.         return buf_size ;

  1667.     }

  1668. 

  1669.     AV_DEBUG("parsed %d bytes %d bits, returned %d samples (*ch*bits) \n", get_bits_count(gb)/8, get_bits_count(gb)%8, len);

  1670. 

  1671.     for(i=0;i<len;++i) {

  1672.         int_fast32_t tmp= ((int32_t*)vc->ret)[i];

  1673.         if(tmp & 0xf0000){

  1674. //            tmp= (0x43c0ffff - tmp)>>31; //ask gcc devs why this is slower

  1675.             if(tmp > 0x43c0ffff) tmp= 0xFFFF;

  1676.             else                 tmp= 0;

  1677.         }

  1678.         ((int16_t*)data)[i]=tmp - 0x8000;

  1679.     }

  1680. 

  1681.     *data_size=len*2;

  1682. 

  1683.     return buf_size ;

  1684. }

  1685. 

  1686. // Close decoder

  1687. 

  1688. static int vorbis_decode_close(AVCodecContext *avccontext) {

  1689.     vorbis_context *vc = avccontext->priv_data;

  1690. 

  1691.     vorbis_free(vc);

  1692. 

  1693.     return 0 ;

  1694. }

  1695. 

  1696. AVCodec vorbis_decoder = {

  1697.     "vorbis",

  1698.     CODEC_TYPE_AUDIO,

  1699.     CODEC_ID_VORBIS,

  1700.     sizeof(vorbis_context),

  1701.     vorbis_decode_init,

  1702.     NULL,

  1703.     vorbis_decode_close,

  1704.     vorbis_decode_frame,

  1705. };