Vorbis decoder by (Balatoni Denes | dbalatoni programozo hu)
[ffmpeg.git] / libavcodec / vorbis.c
1 /**
2  * @file vorbis.c
3  * Vorbis I decoder
4  * @author Denes Balatoni  ( dbalatoni programozo hu )
5  */
6
7 #undef V_DEBUG
8
9 #include <math.h>
10
11 #define ALT_BITSTREAM_READER_LE
12 #include "avcodec.h"
13 #include "bitstream.h"
14 #include "dsputil.h"
15
16 #include "vorbis.h"
17
18 #define V_NB_BITS 11
19 #define V_MAX_VLCS (1<<16)
20
21 #ifndef V_DEBUG
22 #define AV_DEBUG(...)
23 #endif
24
25
26
27 /* Helper functions */
28
29 /**
30  *  reads 0-32 bits when using the ALT_BITSTREAM_READER_LE bitstream reader
31  */
32 unsigned int get_bits_long_le(GetBitContext *s, int n){
33     if(n<=17) return get_bits(s, n);
34     else{
35         int ret= get_bits(s, 16);
36         return ret | (get_bits(s, n-16) << 16);
37     }
38 }
39
40 static unsigned int ilog(unsigned int i) { // unfortunatelly av_log2 uses different rounding
41     unsigned int ret=0;
42     while (i!=0) {
43         ++ret;
44         i>>=1;
45     }
46     return ret;
47 }
48
49 static unsigned int nth_root(unsigned int x, unsigned int n) {   // x^(1/n)
50     unsigned int ret=0, i, j;
51
52     do {
53         ++ret;
54         for(i=0,j=ret;i<n-1;i++) j*=ret;
55     } while (j<=x);
56
57     return (ret-1);
58 }
59
60 static float vorbisfloat2float(uint_fast32_t val) {
61     double mant=val&0x1fffff;
62     long exp=(val&0x7fe00000L)>>21;
63     if (val&0x80000000) mant=-mant;
64     return(ldexp(mant, exp-20-768));
65 }
66
67
68 // Generate vlc codes from vorbis huffman code lengths
69
70 static int vorbis_len2vlc(vorbis_context *vc, uint_fast8_t *bits, uint_fast32_t *codes, uint_fast32_t num) {
71     uint_fast32_t exit_at_level[33]={404,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
72         0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
73
74     uint_fast8_t i,j;
75     uint_fast32_t code,p;
76
77 #ifdef V_DEBUG
78     GetBitContext gb;
79 #endif
80
81     for(p=0;(bits[p]==0) && (p<num);++p);
82     if (p==num) {
83 //        av_log(vc->avccontext, AV_LOG_INFO, "An empty codebook. Heh?! \n");
84         return 0;
85     }
86
87     codes[p]=0;
88     for(i=0;i<bits[p];++i) {
89         exit_at_level[i+1]=1<<i;
90     }
91
92 #ifdef V_DEBUG
93     av_log(vc->avccontext, AV_LOG_INFO, " %d. of %d code len %d code %d - ", p, num, bits[p], codes[p]);
94     init_get_bits(&gb, (uint_fast8_t *)&codes[p], bits[p]);
95     for(i=0;i<bits[p];++i) {
96         av_log(vc->avccontext, AV_LOG_INFO, "%s", get_bits1(&gb) ? "1" : "0");
97     }
98     av_log(vc->avccontext, AV_LOG_INFO, "\n");
99 #endif
100
101     ++p;
102
103     for(;p<num;++p) {
104         if (bits[p]==0) continue;
105         // find corresponding exit(node which the tree can grow further from)
106         for(i=bits[p];i>0;--i) {
107             if (exit_at_level[i]) break;
108         }
109         if (!i) return 1; // overspecified tree
110         code=exit_at_level[i];
111         exit_at_level[i]=0;
112         // construct code (append 0s to end) and introduce new exits
113         for(j=i+1;j<=bits[p];++j) {
114             exit_at_level[j]=code+(1<<(j-1));
115         }
116         codes[p]=code;
117
118 #ifdef V_DEBUG
119         av_log(vc->avccontext, AV_LOG_INFO, " %d. code len %d code %d - ", p, bits[p], codes[p]);
120         init_get_bits(&gb, (uint_fast8_t *)&codes[p], bits[p]);
121         for(i=0;i<bits[p];++i) {
122             av_log(vc->avccontext, AV_LOG_INFO, "%s", get_bits1(&gb) ? "1" : "0");
123         }
124         av_log(vc->avccontext, AV_LOG_INFO, "\n");
125 #endif
126
127     }
128
129     //FIXME no exits should be left (underspecified tree - ie. unused valid vlcs - not allowed by SPEC)
130
131     return 0;
132 }
133
134 // Free all allocated memory -----------------------------------------
135
136 static void vorbis_free(vorbis_context *vc) {
137     int_fast16_t i;
138
139     av_freep(&vc->channel_residues);
140     av_freep(&vc->channel_floors);
141     av_freep(&vc->saved);
142     av_freep(&vc->ret);
143
144     av_freep(&vc->residues);
145     av_freep(&vc->modes);
146
147     ff_mdct_end(&vc->mdct0);
148     ff_mdct_end(&vc->mdct1);
149
150     for(i=0;i<vc->codebook_count;++i) {
151         av_free(vc->codebooks[i].codevectors);
152         free_vlc(&vc->codebooks[i].vlc);
153     }
154     av_freep(&vc->codebooks);
155
156     for(i=0;i<vc->floor_count;++i) {
157         av_free(vc->floors[i].x_list);
158         av_free(vc->floors[i].x_list_order);
159         av_free(vc->floors[i].low_neighbour);
160         av_free(vc->floors[i].high_neighbour);
161     }
162     av_freep(&vc->floors);
163
164     for(i=0;i<vc->mapping_count;++i) {
165         av_free(vc->mappings[i].magnitude);
166         av_free(vc->mappings[i].angle);
167         av_free(vc->mappings[i].mux);
168     }
169     av_freep(&vc->mappings);
170 }
171
172 // Parse setup header -------------------------------------------------
173
174 // Process codebooks part
175
176 static int vorbis_parse_setup_hdr_codebooks(vorbis_context *vc) {
177     uint_fast16_t cb;
178     GetBitContext *gb=&vc->gb;
179
180     vc->codebook_count=get_bits(gb,8)+1;
181
182     AV_DEBUG(" Codebooks: %d \n", vc->codebook_count);
183
184     vc->codebooks=(vorbis_codebook *)av_mallocz(vc->codebook_count * sizeof(vorbis_codebook));
185
186     for(cb=0;cb<vc->codebook_count;++cb) {
187         vorbis_codebook *codebook_setup=&vc->codebooks[cb];
188         uint_fast8_t ordered;
189         uint_fast32_t t, used_entries=0;
190         uint_fast32_t entries;
191         uint_fast8_t tmp_vlc_bits[V_MAX_VLCS];
192         uint_fast32_t tmp_vlc_codes[V_MAX_VLCS];
193
194 //        memset(tmp_vlc_bits, 0, sizeof(tmp_vlc_bits));
195
196         AV_DEBUG(" %d. Codebook \n", cb);
197
198         if (get_bits(gb, 24)!=0x564342) {
199             av_log(vc->avccontext, AV_LOG_ERROR, " %d. Codebook setup data corrupt. \n", cb);
200             return 1;
201         }
202
203         codebook_setup->dimensions=get_bits(gb, 16);
204         if (codebook_setup->dimensions>16) {
205             av_log(vc->avccontext, AV_LOG_ERROR, " %d. Codebook's dimension is too large (%d). \n", cb, codebook_setup->dimensions);
206             return 1;
207         }
208         entries=get_bits(gb, 24);
209         if (entries>V_MAX_VLCS) {
210             av_log(vc->avccontext, AV_LOG_ERROR, " %d. Codebook has too many entries (%d). \n", cb, entries);
211             return 1;
212         }
213
214         ordered=get_bits1(gb);
215
216         AV_DEBUG(" codebook_dimensions %d, codebook_entries %d \n", codebook_setup->dimensions, entries);
217
218         if (!ordered) {
219             uint_fast16_t ce;
220             uint_fast8_t flag;
221             uint_fast8_t sparse=get_bits1(gb);
222
223             AV_DEBUG(" not ordered \n");
224
225             if (sparse) {
226                 AV_DEBUG(" sparse \n");
227
228                 used_entries=0;
229                 for(ce=0;ce<entries;++ce) {
230                     flag=get_bits1(gb);
231                     if (flag) {
232                         tmp_vlc_bits[ce]=get_bits(gb, 5)+1;
233                         ++used_entries;
234                     }
235                     else tmp_vlc_bits[ce]=0;
236                 }
237             } else {
238                 AV_DEBUG(" not sparse \n");
239
240                 used_entries=entries;
241                 for(ce=0;ce<entries;++ce) {
242                     tmp_vlc_bits[ce]=get_bits(gb, 5)+1;
243                 }
244             }
245         } else {
246             uint_fast16_t current_entry=0;
247             uint_fast8_t current_length=get_bits(gb, 5)+1;
248
249             AV_DEBUG(" ordered, current length: %d \n", current_length);  //FIXME
250
251             used_entries=entries;
252             for(;current_entry<used_entries;++current_length) {
253                 uint_fast16_t i, number;
254
255                 AV_DEBUG(" number bits: %d ", ilog(entries - current_entry));
256
257                 number=get_bits(gb, ilog(entries - current_entry));
258
259                 AV_DEBUG(" number: %d \n", number);
260
261                 for(i=current_entry;i<number+current_entry;++i) {
262                     if (i<used_entries) tmp_vlc_bits[i]=current_length;
263                 }
264
265                 current_entry+=number;
266             }
267             if (current_entry>used_entries) {
268                 av_log(vc->avccontext, AV_LOG_ERROR, " More codelengths than codes in codebook. \n");
269                 return 1;
270             }
271         }
272
273         codebook_setup->lookup_type=get_bits(gb, 4);
274
275         AV_DEBUG(" lookup type: %d : %s \n", codebook_setup->lookup_type, codebook_setup->lookup_type ? "vq" : "no lookup" );
276
277 // If the codebook is used for (inverse) VQ, calculate codevectors.
278
279         if (codebook_setup->lookup_type==1) {
280             uint_fast16_t i, j, k;
281             uint_fast16_t codebook_lookup_values=nth_root(entries, codebook_setup->dimensions);
282             uint_fast16_t codebook_multiplicands[codebook_lookup_values];
283
284             float codebook_minimum_value=vorbisfloat2float(get_bits_long_le(gb, 32));
285             float codebook_delta_value=vorbisfloat2float(get_bits_long_le(gb, 32));
286             uint_fast8_t codebook_value_bits=get_bits(gb, 4)+1;
287             uint_fast8_t codebook_sequence_p=get_bits1(gb);
288
289             AV_DEBUG(" We expect %d numbers for building the codevectors. \n", codebook_lookup_values);
290             AV_DEBUG("  delta %f minmum %f \n", codebook_delta_value, codebook_minimum_value);
291
292             for(i=0;i<codebook_lookup_values;++i) {
293                 codebook_multiplicands[i]=get_bits(gb, codebook_value_bits);
294
295                 AV_DEBUG(" multiplicands*delta+minmum : %e \n", (float)codebook_multiplicands[i]*codebook_delta_value+codebook_minimum_value);
296                 AV_DEBUG(" multiplicand %d \n", codebook_multiplicands[i]);
297             }
298
299 // Weed out unused vlcs and build codevector vector
300             codebook_setup->codevectors=(float *)av_mallocz(used_entries*codebook_setup->dimensions * sizeof(float));
301             for(j=0, i=0;i<entries;++i) {
302                 uint_fast8_t dim=codebook_setup->dimensions;
303
304                 if (tmp_vlc_bits[i]) {
305                     float last=0.0;
306                     uint_fast32_t lookup_offset=i;
307
308 #ifdef V_DEBUG
309                     av_log(vc->avccontext, AV_LOG_INFO, "Lookup offset %d ,", i);
310 #endif
311
312                     for(k=0;k<dim;++k) {
313                         uint_fast32_t multiplicand_offset = lookup_offset % codebook_lookup_values;
314                         codebook_setup->codevectors[j*dim+k]=codebook_multiplicands[multiplicand_offset]*codebook_delta_value+codebook_minimum_value+last;
315                         if (codebook_sequence_p) {
316                             last=codebook_setup->codevectors[j*dim+k];
317                         }
318                         lookup_offset/=codebook_lookup_values;
319                     }
320                     tmp_vlc_bits[j]=tmp_vlc_bits[i];
321
322 #ifdef V_DEBUG
323                     av_log(vc->avccontext, AV_LOG_INFO, "real lookup offset %d, vector: ", j);
324                     for(k=0;k<dim;++k) {
325                         av_log(vc->avccontext, AV_LOG_INFO, " %f ", codebook_setup->codevectors[j*dim+k]);
326                     }
327                     av_log(vc->avccontext, AV_LOG_INFO, "\n");
328 #endif
329
330                     ++j;
331                 }
332             }
333             if (j!=used_entries) {
334                 av_log(vc->avccontext, AV_LOG_ERROR, "Bug in codevector vector building code. \n");
335                 return 1;
336             }
337             entries=used_entries;
338         }
339         else if (codebook_setup->lookup_type>=2) {
340             av_log(vc->avccontext, AV_LOG_ERROR, "Codebook lookup type not supported. \n");
341             return 1;
342         }
343
344 // Initialize VLC table
345         if (vorbis_len2vlc(vc, tmp_vlc_bits, tmp_vlc_codes, entries)) {
346             av_log(vc->avccontext, AV_LOG_ERROR, " Invalid code lengths while generating vlcs. \n");
347             return 1;
348         }
349         codebook_setup->maxdepth=0;
350         for(t=0;t<entries;++t)
351             if (tmp_vlc_bits[t]>=codebook_setup->maxdepth) codebook_setup->maxdepth=tmp_vlc_bits[t];
352
353         codebook_setup->maxdepth=(codebook_setup->maxdepth+V_NB_BITS-1)/V_NB_BITS;
354
355         if (init_vlc(&codebook_setup->vlc, V_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)) {
356             av_log(vc->avccontext, AV_LOG_ERROR, " Error generating vlc tables. \n");
357             return 1;
358         }
359     }
360     return 0;
361 }
362
363 // Process time domain transforms part (unused in Vorbis I)
364
365 static int vorbis_parse_setup_hdr_tdtransforms(vorbis_context *vc) {
366     GetBitContext *gb=&vc->gb;
367     uint_fast8_t i;
368     uint_fast8_t vorbis_time_count=get_bits(gb, 6)+1;
369
370     for(i=0;i<vorbis_time_count;++i) {
371         uint_fast16_t vorbis_tdtransform=get_bits(gb, 16);
372
373         AV_DEBUG(" Vorbis time domain transform %d: %d \n", vorbis_time_count, vorbis_tdtransform);
374
375         if (vorbis_tdtransform) {
376             av_log(vc->avccontext, AV_LOG_ERROR, "Vorbis time domain transform data nonzero. \n");
377             return 1;
378         }
379     }
380     return 0;
381 }
382
383 // Process floors part - only floor type 1 is supported
384
385 static int vorbis_parse_setup_hdr_floors(vorbis_context *vc) {
386     GetBitContext *gb=&vc->gb;
387     uint_fast16_t i,j,k;
388
389     vc->floor_count=get_bits(gb, 6)+1;
390
391     vc->floors=(vorbis_floor *)av_mallocz(vc->floor_count * sizeof(vorbis_floor));
392
393     for (i=0;i<vc->floor_count;++i) {
394         vorbis_floor *floor_setup=&vc->floors[i];
395
396         floor_setup->floor_type=get_bits(gb, 16);
397
398         AV_DEBUG(" %d. floor type %d \n", i, floor_setup->floor_type);
399
400         if (floor_setup->floor_type==1) {
401             uint_fast8_t maximum_class=0;
402             uint_fast8_t rangebits;
403             uint_fast16_t floor1_values=2;
404
405             floor_setup->partitions=get_bits(gb, 5);
406
407             AV_DEBUG(" %d.floor: %d partitions \n", i, floor_setup->partitions);
408
409             for(j=0;j<floor_setup->partitions;++j) {
410                 floor_setup->partition_class[j]=get_bits(gb, 4);
411                 if (floor_setup->partition_class[j]>maximum_class) maximum_class=floor_setup->partition_class[j];
412
413                 AV_DEBUG(" %d. floor %d partition class %d \n", i, j, floor_setup->partition_class[j]);
414
415             }
416
417             AV_DEBUG(" maximum class %d \n", maximum_class);
418
419             floor_setup->maximum_class=maximum_class;
420
421             for(j=0;j<=maximum_class;++j) {
422                 floor_setup->class_dimensions[j]=get_bits(gb, 3)+1;
423                 floor_setup->class_subclasses[j]=get_bits(gb, 2);
424
425                 AV_DEBUG(" %d floor %d class dim: %d subclasses %d \n", i, j, floor_setup->class_dimensions[j], floor_setup->class_subclasses[j]);
426
427                 if (floor_setup->class_subclasses[j]) {
428                     floor_setup->class_masterbook[j]=get_bits(gb, 8);
429
430                     AV_DEBUG("   masterbook: %d \n", floor_setup->class_masterbook[j]);
431                 }
432
433                 for(k=0;k<(1<<floor_setup->class_subclasses[j]);++k) {
434                     floor_setup->subclass_books[j][k]=get_bits(gb, 8)-1;
435
436                     AV_DEBUG("    book %d. : %d \n", k, floor_setup->subclass_books[j][k]);
437                 }
438             }
439
440             floor_setup->multiplier=get_bits(gb, 2)+1;
441             floor_setup->x_list_dim=2;
442
443             for(j=0;j<floor_setup->partitions;++j) {
444                 floor_setup->x_list_dim+=floor_setup->class_dimensions[floor_setup->partition_class[j]];
445             }
446
447             floor_setup->x_list=(uint_fast16_t *)av_mallocz(floor_setup->x_list_dim * sizeof(uint_fast16_t));
448             floor_setup->x_list_order=(uint_fast16_t *)av_mallocz(floor_setup->x_list_dim * sizeof(uint_fast16_t));
449             floor_setup->low_neighbour=(uint_fast16_t *)av_mallocz(floor_setup->x_list_dim * sizeof(uint_fast16_t));
450             floor_setup->high_neighbour=(uint_fast16_t *)av_mallocz(floor_setup->x_list_dim * sizeof(uint_fast16_t));
451
452
453             rangebits=get_bits(gb, 4);
454             floor_setup->x_list[0] = 0;
455             floor_setup->x_list[1] = (1<<rangebits);
456
457             for(j=0;j<floor_setup->partitions;++j) {
458                 for(k=0;k<floor_setup->class_dimensions[floor_setup->partition_class[j]];++k,++floor1_values) {
459                     floor_setup->x_list[floor1_values]=get_bits(gb, rangebits);
460
461                     AV_DEBUG(" %d. floor1 Y coord. %d \n", floor1_values, floor_setup->x_list[floor1_values]);
462                 }
463             }
464
465 // Precalculate order of x coordinates - needed for decode
466
467             for(k=0;k<floor_setup->x_list_dim;++k) {
468                 floor_setup->x_list_order[k]=k;
469             }
470
471             for(k=0;k<floor_setup->x_list_dim-1;++k) {   // FIXME optimize sorting ?
472                 for(j=k+1;j<floor_setup->x_list_dim;++j) {
473                     if(floor_setup->x_list[floor_setup->x_list_order[k]]>floor_setup->x_list[floor_setup->x_list_order[j]]) {
474                         uint_fast16_t tmp=floor_setup->x_list_order[k];
475                         floor_setup->x_list_order[k]=floor_setup->x_list_order[j];
476                         floor_setup->x_list_order[j]=tmp;
477                     }
478                 }
479             }
480
481 // Precalculate low and high neighbours
482
483             for(k=2;k<floor_setup->x_list_dim;++k) {
484                 floor_setup->low_neighbour[k]=0;
485                 floor_setup->high_neighbour[k]=1;  // correct according to SPEC requirements
486
487                 for (j=0;j<k;++j) {
488                     if ((floor_setup->x_list[j]<floor_setup->x_list[k]) &&
489                       (floor_setup->x_list[j]>floor_setup->x_list[floor_setup->low_neighbour[k]])) {
490                         floor_setup->low_neighbour[k]=j;
491                     }
492                     if ((floor_setup->x_list[j]>floor_setup->x_list[k]) &&
493                       (floor_setup->x_list[j]<floor_setup->x_list[floor_setup->high_neighbour[k]])) {
494                         floor_setup->high_neighbour[k]=j;
495                     }
496                 }
497             }
498         }
499         else {
500             av_log(vc->avccontext, AV_LOG_ERROR, "Only floor type 1 supported. \n");
501             return 1;
502         }
503     }
504     return 0;
505 }
506
507 // Process residues part
508
509 static int vorbis_parse_setup_hdr_residues(vorbis_context *vc){
510     GetBitContext *gb=&vc->gb;
511     uint_fast8_t i, j, k;
512
513     vc->residue_count=get_bits(gb, 6)+1;
514     vc->residues=(vorbis_residue *)av_mallocz(vc->residue_count * sizeof(vorbis_residue));
515
516     AV_DEBUG(" There are %d residues. \n", vc->residue_count);
517
518     for(i=0;i<vc->residue_count;++i) {
519         vorbis_residue *res_setup=&vc->residues[i];
520         uint_fast8_t cascade[64];
521         uint_fast8_t high_bits;
522         uint_fast8_t low_bits;
523
524         res_setup->type=get_bits(gb, 16);
525
526         AV_DEBUG(" %d. residue type %d \n", i, res_setup->type);
527
528         res_setup->begin=get_bits(gb, 24);
529         res_setup->end=get_bits(gb, 24);
530         res_setup->partition_size=get_bits(gb, 24)+1;
531         res_setup->classifications=get_bits(gb, 6)+1;
532         res_setup->classbook=get_bits(gb, 8);
533
534         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,
535           res_setup->classifications, res_setup->classbook);
536
537         for(j=0;j<res_setup->classifications;++j) {
538             high_bits=0;
539             low_bits=get_bits(gb, 3);
540             if (get_bits1(gb)) {
541                 high_bits=get_bits(gb, 5);
542             }
543             cascade[j]=(high_bits<<3)+low_bits;
544
545             AV_DEBUG("     %d class casscade depth: %d \n", j, ilog(cascade[j]));
546         }
547
548         res_setup->maxpass=0;
549         for(j=0;j<res_setup->classifications;++j) {
550             for(k=0;k<8;++k) {
551                 if (cascade[j]&(1<<k)) {
552                         res_setup->books[j][k]=get_bits(gb, 8);
553
554                     AV_DEBUG("     %d class casscade depth %d book: %d \n", j, k, res_setup->books[j][k]);
555
556                     if (k>res_setup->maxpass) {
557                         res_setup->maxpass=k;
558                     }
559                 } else {
560                     res_setup->books[j][k]=-1;
561                 }
562             }
563         }
564     }
565     return 0;
566 }
567
568 // Process mappings part
569
570 static int vorbis_parse_setup_hdr_mappings(vorbis_context *vc) {
571     GetBitContext *gb=&vc->gb;
572     uint_fast8_t i, j;
573
574     vc->mapping_count=get_bits(gb, 6)+1;
575     vc->mappings=(vorbis_mapping *)av_mallocz(vc->mapping_count * sizeof(vorbis_mapping));
576
577     AV_DEBUG(" There are %d mappings. \n", vc->mapping_count);
578
579     for(i=0;i<vc->mapping_count;++i) {
580         vorbis_mapping *mapping_setup=&vc->mappings[i];
581
582         if (get_bits(gb, 16)) {
583             av_log(vc->avccontext, AV_LOG_ERROR, "Other mappings than type 0 are not compliant with the Vorbis I specification. \n");
584             return 1;
585         }
586         if (get_bits1(gb)) {
587             mapping_setup->submaps=get_bits(gb, 4)+1;
588         } else {
589             mapping_setup->submaps=1;
590         }
591
592         if (get_bits1(gb)) {
593             mapping_setup->coupling_steps=get_bits(gb, 8)+1;
594             mapping_setup->magnitude=(uint_fast8_t *)av_mallocz(mapping_setup->coupling_steps * sizeof(uint_fast8_t));
595             mapping_setup->angle=(uint_fast8_t *)av_mallocz(mapping_setup->coupling_steps * sizeof(uint_fast8_t));
596             for(j=0;j<mapping_setup->coupling_steps;++j) {
597                 mapping_setup->magnitude[j]=get_bits(gb, ilog(vc->audio_channels-1));
598                 mapping_setup->angle[j]=get_bits(gb, ilog(vc->audio_channels-1));
599                 // FIXME: sanity checks
600             }
601         } else {
602             mapping_setup->coupling_steps=0;
603         }
604
605         AV_DEBUG("   %d mapping coupling steps: %d \n", i, mapping_setup->coupling_steps);
606
607         if(get_bits(gb, 2)) {
608             av_log(vc->avccontext, AV_LOG_ERROR, "%d. mapping setup data invalid. \n", i);
609             return 1; // following spec.
610         }
611
612         if (mapping_setup->submaps>1) {
613             mapping_setup->mux=(uint_fast8_t *)av_mallocz(vc->audio_channels * sizeof(uint_fast8_t));
614             for(j=0;j<vc->audio_channels;++j) {
615                 mapping_setup->mux[j]=get_bits(gb, 4);
616             }
617         }
618
619         for(j=0;j<mapping_setup->submaps;++j) {
620             get_bits(gb, 8); // FIXME check?
621             mapping_setup->submap_floor[j]=get_bits(gb, 8);
622             mapping_setup->submap_residue[j]=get_bits(gb, 8);
623
624             AV_DEBUG("   %d mapping %d submap : floor %d, residue %d \n", i, j, mapping_setup->submap_floor[j], mapping_setup->submap_residue[j]);
625         }
626     }
627     return 0;
628 }
629
630 // Process modes part
631
632 static int vorbis_parse_setup_hdr_modes(vorbis_context *vc) {
633     GetBitContext *gb=&vc->gb;
634     uint_fast8_t i;
635
636     vc->mode_count=get_bits(gb, 6)+1;
637     vc->modes=(vorbis_mode *)av_mallocz(vc->mode_count * sizeof(vorbis_mode));
638
639     AV_DEBUG(" There are %d modes.\n", vc->mode_count);
640
641     for(i=0;i<vc->mode_count;++i) {
642         vorbis_mode *mode_setup=&vc->modes[i];
643
644         mode_setup->blockflag=get_bits(gb, 1);
645         mode_setup->windowtype=get_bits(gb, 16); //FIXME check
646         mode_setup->transformtype=get_bits(gb, 16); //FIXME check
647         mode_setup->mapping=get_bits(gb, 8); //FIXME check
648
649         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);
650     }
651     return 0;
652 }
653
654 // Process the whole setup header using the functions above
655
656 static int vorbis_parse_setup_hdr(vorbis_context *vc) {
657     GetBitContext *gb=&vc->gb;
658
659     if ((get_bits(gb, 8)!='v') || (get_bits(gb, 8)!='o') ||
660     (get_bits(gb, 8)!='r') || (get_bits(gb, 8)!='b') ||
661     (get_bits(gb, 8)!='i') || (get_bits(gb, 8)!='s')) {
662         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (no vorbis signature). \n");
663         return 1;
664     }
665
666     if (vorbis_parse_setup_hdr_codebooks(vc)) {
667         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (codebooks). \n");
668         return 2;
669     }
670     if (vorbis_parse_setup_hdr_tdtransforms(vc)) {
671         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (time domain transforms). \n");
672         return 3;
673     }
674     if (vorbis_parse_setup_hdr_floors(vc)) {
675         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (floors). \n");
676         return 4;
677     }
678     if (vorbis_parse_setup_hdr_residues(vc)) {
679         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (residues). \n");
680         return 5;
681     }
682     if (vorbis_parse_setup_hdr_mappings(vc)) {
683         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (mappings). \n");
684         return 6;
685     }
686     if (vorbis_parse_setup_hdr_modes(vc)) {
687         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (modes). \n");
688         return 7;
689     }
690     if (!get_bits1(gb)) {
691         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (framing flag). \n");
692         return 8; // framing flag bit unset error
693     }
694
695     return 0;
696 }
697
698 // Process the identification header
699
700 static int vorbis_parse_id_hdr(vorbis_context *vc){
701     GetBitContext *gb=&vc->gb;
702     uint_fast8_t bl0, bl1;
703     const float *vwin[8]={ vwin64, vwin128, vwin256, vwin512, vwin1024, vwin2048, vwin4096, vwin8192 };
704
705     if ((get_bits(gb, 8)!='v') || (get_bits(gb, 8)!='o') ||
706     (get_bits(gb, 8)!='r') || (get_bits(gb, 8)!='b') ||
707     (get_bits(gb, 8)!='i') || (get_bits(gb, 8)!='s')) {
708         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis id header packet corrupt (no vorbis signature). \n");
709         return 1;
710     }
711
712     vc->version=get_bits_long_le(gb, 32);    //FIXME check 0
713     vc->audio_channels=get_bits(gb, 8);   //FIXME check >0
714     vc->audio_samplerate=get_bits_long_le(gb, 32);   //FIXME check >0
715     vc->bitrate_maximum=get_bits_long_le(gb, 32);
716     vc->bitrate_nominal=get_bits_long_le(gb, 32);
717     vc->bitrate_minimum=get_bits_long_le(gb, 32);
718     bl0=get_bits(gb, 4);
719     bl1=get_bits(gb, 4);
720     vc->blocksize_0=(1<<bl0);
721     vc->blocksize_1=(1<<bl1);
722     if (bl0>13 || bl0<6 || bl1>13 || bl1<6) {
723         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis id header packet corrupt (illegal blocksize). \n");
724         return 3;
725     }
726     vc->swin=vwin[bl0-6];
727     vc->lwin=vwin[bl1-6];
728
729     if ((get_bits1(gb)) == 0) {
730         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis id header packet corrupt (framing flag not set). \n");
731         return 2;
732     }
733
734     vc->channel_residues=(float *)av_malloc((vc->blocksize_1/2)*vc->audio_channels * sizeof(float));
735     vc->channel_floors=(float *)av_malloc((vc->blocksize_1/2)*vc->audio_channels * sizeof(float));
736     vc->saved=(float *)av_malloc((vc->blocksize_1/2)*vc->audio_channels * sizeof(float));
737     vc->ret=(float *)av_malloc((vc->blocksize_1/2)*vc->audio_channels * sizeof(float));
738     vc->saved_start=0;
739
740     ff_mdct_init(&vc->mdct0, bl0, 1);
741     ff_mdct_init(&vc->mdct1, bl1, 1);
742
743     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 ",
744             vc->version, vc->audio_channels, vc->audio_samplerate, vc->bitrate_maximum, vc->bitrate_nominal, vc->bitrate_minimum, vc->blocksize_0, vc->blocksize_1);
745
746 /*
747     BLK=vc->blocksize_0;
748     for(i=0;i<BLK/2;++i) {
749         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)));
750     }
751 */
752
753     return 0;
754 }
755
756 // Process the extradata using the functions above (identification header, setup header)
757
758 static int vorbis_decode_init(AVCodecContext *avccontext) {
759     vorbis_context *vc = avccontext->priv_data ;
760     uint8_t *headers = avccontext->extradata;
761     int headers_len=avccontext->extradata_size;
762     int header_len[3];
763     GetBitContext *gb = &(vc->gb);
764     int i, j, hdr_type;
765
766     vc->avccontext = avccontext;
767
768     if (!headers_len || headers[0]!=2) {
769         av_log(avccontext, AV_LOG_ERROR, "Extradata corrupt.\n");
770         return -1;
771     }
772
773     for(j=1,i=0;i<2;++i, ++j) {
774         header_len[i]=0;
775         while(j<headers_len && headers[j]==0xff) {
776             header_len[i]+=0xff;
777             ++j;
778         }
779         if (j>=headers_len) {
780             av_log(avccontext, AV_LOG_ERROR, "Extradata corrupt.\n");
781             return -1;
782         }
783         header_len[i]+=headers[j];
784     }
785     header_len[2]=headers_len-header_len[0]-header_len[1]-j;
786     headers+=j;
787
788     init_get_bits(gb, headers, header_len[0]*8);
789     hdr_type=get_bits(gb, 8);
790     if (hdr_type!=1) {
791         av_log(avccontext, AV_LOG_ERROR, "First header is not the id header.\n");
792         return -1;
793     }
794     if (vorbis_parse_id_hdr(vc)) {
795         av_log(avccontext, AV_LOG_ERROR, "Id header corrupt.\n");
796         vorbis_free(vc);
797         return -1;
798     }
799
800     init_get_bits(gb, headers+header_len[0]+header_len[1], header_len[2]*8);
801     hdr_type=get_bits(gb, 8);
802     if (hdr_type!=5) {
803         av_log(avccontext, AV_LOG_ERROR, "Third header is not the setup header.\n");
804         return -1;
805     }
806     if (vorbis_parse_setup_hdr(vc)) {
807         av_log(avccontext, AV_LOG_ERROR, "Setup header corrupt.\n");
808         vorbis_free(vc);
809         return -1;
810     }
811
812     avccontext->channels = vc->audio_channels;
813     avccontext->sample_rate = vc->audio_samplerate;
814
815     return 0 ;
816 }
817
818 // Decode audiopackets -------------------------------------------------
819
820 // Read and decode floor (type 1 only)
821
822 static uint_fast8_t vorbis_floor1_decode(vorbis_context *vc, vorbis_floor *vf, float *vec) {
823     GetBitContext *gb=&vc->gb;
824     uint_fast16_t range_v[4]={ 256, 128, 86, 64 };
825     uint_fast16_t range=range_v[vf->multiplier-1];
826     uint_fast16_t floor1_Y[vf->x_list_dim];
827     uint_fast16_t floor1_Y_final[vf->x_list_dim];
828     uint_fast8_t floor1_flag[vf->x_list_dim];
829     uint_fast8_t class_;
830     uint_fast8_t cdim;
831     uint_fast8_t cbits;
832     uint_fast8_t csub;
833     uint_fast8_t cval;
834     int_fast16_t book;
835     uint_fast16_t offset;
836     uint_fast16_t i,j;
837     uint_fast16_t *floor_x_sort=vf->x_list_order;
838     /*u*/int_fast16_t adx, ady, off, predicted; // WTF ? dy/adx= (unsigned)dy/adx ?
839     int_fast16_t dy, err;
840     uint_fast16_t lx,hx, ly, hy=0;
841
842
843     if (!get_bits1(gb)) return 1; // silence
844
845 // Read values (or differences) for the floor's points
846
847     floor1_Y[0]=get_bits(gb, ilog(range-1));
848     floor1_Y[1]=get_bits(gb, ilog(range-1));
849
850     AV_DEBUG("floor 0 Y %d floor 1 Y %d \n", floor1_Y[0], floor1_Y[1]);
851
852     offset=2;
853     for(i=0;i<vf->partitions;++i) {
854         class_=vf->partition_class[i];
855         cdim=vf->class_dimensions[class_];
856         cbits=vf->class_subclasses[class_];
857         csub=(1<<cbits)-1;
858         cval=0;
859
860         AV_DEBUG("Cbits %d \n", cbits);
861
862         if (cbits) { // this reads all subclasses for this partition's class
863             cval=get_vlc2(gb, vc->codebooks[vf->class_masterbook[class_]].vlc.table,
864             V_NB_BITS, vc->codebooks[vf->class_masterbook[class_]].maxdepth);
865         }
866
867         for(j=0;j<cdim;++j) {
868             book=vf->subclass_books[class_][cval & csub];
869
870             AV_DEBUG("book %d Cbits %d cval %d  bits:%d \n", book, cbits, cval, get_bits_count(gb));
871
872             cval=cval>>cbits;
873             if (book>0) {
874                 floor1_Y[offset+j]=get_vlc2(gb, vc->codebooks[book].vlc.table,
875                 V_NB_BITS, vc->codebooks[book].maxdepth);
876             } else {
877                 floor1_Y[offset+j]=0;
878             }
879
880             AV_DEBUG(" floor(%d) = %d \n", vf->x_list[offset+j], floor1_Y[offset+j]);
881         }
882         offset+=cdim;
883     }
884
885 // Amplitude calculation from the differences
886
887     floor1_flag[0]=1;
888     floor1_flag[1]=1;
889     floor1_Y_final[0]=floor1_Y[0];
890     floor1_Y_final[1]=floor1_Y[1];
891
892     for(i=2;i<vf->x_list_dim;++i) {
893         uint_fast16_t val, highroom, lowroom, room;
894         uint_fast16_t high_neigh_offs;
895         uint_fast16_t low_neigh_offs;
896
897         low_neigh_offs=vf->low_neighbour[i];
898         high_neigh_offs=vf->high_neighbour[i];
899         dy=floor1_Y_final[high_neigh_offs]-floor1_Y_final[low_neigh_offs];  // render_point begin
900         adx=vf->x_list[high_neigh_offs]-vf->x_list[low_neigh_offs];
901         ady= ABS(dy);
902         err=ady*(vf->x_list[i]-vf->x_list[low_neigh_offs]);
903         off=err/adx;
904         if (dy<0) {
905             predicted=floor1_Y_final[low_neigh_offs]-off;
906         } else {
907             predicted=floor1_Y_final[low_neigh_offs]+off;
908         } // render_point end
909
910         val=floor1_Y[i];
911         highroom=range-predicted;
912         lowroom=predicted;
913         if (highroom < lowroom) {
914             room=highroom*2;
915         } else {
916             room=lowroom*2;   // SPEC mispelling
917         }
918         if (val) {
919             floor1_flag[low_neigh_offs]=1;
920             floor1_flag[high_neigh_offs]=1;
921             floor1_flag[i]=1;
922             if (val>=room) {
923                 if (highroom > lowroom) {
924                     floor1_Y_final[i]=val-lowroom+predicted;
925                 } else {
926                     floor1_Y_final[i]=predicted-val+highroom-1;
927                 }
928             } else {
929                 if (val & 1) {
930                     floor1_Y_final[i]=predicted-(val+1)/2;
931                 } else {
932                     floor1_Y_final[i]=predicted+val/2;
933                 }
934             }
935         } else {
936             floor1_flag[i]=0;
937             floor1_Y_final[i]=predicted;
938         }
939
940         AV_DEBUG(" Decoded floor(%d) = %d / val %d \n", vf->x_list[i], floor1_Y_final[i], val);
941     }
942
943 // Curve synth - connect the calculated dots and convert from dB scale FIXME optimize ?
944
945     hx=0;
946     lx=0;
947     ly=floor1_Y_final[0]*vf->multiplier;  // conforms to SPEC
948
949     vec[0]=floor1_inverse_db_table[ly];
950
951     for(i=1;i<vf->x_list_dim;++i) {
952         AV_DEBUG(" Looking at post %d \n", i);
953
954         if (floor1_flag[floor_x_sort[i]]) {   // SPEC mispelled
955             int_fast16_t x, y, dy, base, sy; // if uncommented: dy = -32 adx = 2  base = 2blablabla ?????
956
957             hy=floor1_Y_final[floor_x_sort[i]]*vf->multiplier;
958             hx=vf->x_list[floor_x_sort[i]];
959
960             dy=hy-ly;
961             adx=hx-lx;
962             ady= (dy<0) ? -dy:dy;//ABS(dy);
963             base=dy/adx;
964
965             AV_DEBUG(" dy %d  adx %d base %d = %d \n", dy, adx, base, dy/adx);
966
967             x=lx;
968             y=ly;
969             err=0;
970             if (dy<0) {
971                 sy=base-1;
972             } else {
973                 sy=base+1;
974             }
975             ady=ady-(base<0 ? -base : base)*adx;
976             vec[x]=floor1_inverse_db_table[y];
977
978             AV_DEBUG(" vec[ %d ] = %d \n", x, y);
979
980             for(x=lx+1;(x<hx) && (x<vf->x_list[1]);++x) {
981                 err+=ady;
982                 if (err>=adx) {
983                     err-=adx;
984                     y+=sy;
985                 } else {
986                     y+=base;
987                 }
988                 vec[x]=floor1_inverse_db_table[y];
989
990                 AV_DEBUG(" vec[ %d ] = %d \n", x, y);
991             }
992
993 /*            for(j=1;j<hx-lx+1;++j) {  // iterating render_point
994                 dy=hy-ly;
995                 adx=hx-lx;
996                 ady= dy<0 ? -dy : dy;
997                 err=ady*j;
998                 off=err/adx;
999                 if (dy<0) {
1000                     predicted=ly-off;
1001                 } else {
1002                     predicted=ly+off;
1003                 }
1004                 if (lx+j < vf->x_list[1]) {
1005                     vec[lx+j]=floor1_inverse_db_table[predicted];
1006                 }
1007             }*/
1008
1009             lx=hx;
1010             ly=hy;
1011         }
1012     }
1013
1014     if (hx<vf->x_list[1]) {
1015         for(i=hx;i<vf->x_list[1];++i) {
1016             vec[i]=floor1_inverse_db_table[hy];
1017         }
1018     }
1019
1020     AV_DEBUG(" Floor decoded\n");
1021
1022     return 0;
1023 }
1024
1025 // Read and decode residue
1026
1027 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) {
1028     GetBitContext *gb=&vc->gb;
1029     uint_fast8_t c_p_c=vc->codebooks[vr->classbook].dimensions;
1030     uint_fast16_t n_to_read=vr->end-vr->begin;
1031     uint_fast16_t ptns_to_read=n_to_read/vr->partition_size;
1032     uint_fast8_t classifs[ptns_to_read];
1033     uint_fast8_t pass;
1034     uint_fast8_t ch_used;
1035     uint_fast8_t i,j,l;
1036     uint_fast16_t k;
1037
1038     if (vr->type==2) {
1039         for(j=1;j<ch;++j) {
1040                 do_not_decode[0]&=do_not_decode[j];  // FIXME - clobbering input
1041         }
1042         if (do_not_decode[0]) return 0;
1043         ch_used=1;
1044     } else {
1045         ch_used=ch;
1046     }
1047
1048     AV_DEBUG(" residue type 0/1/2 decode begin, ch: %d  cpc %d  \n", ch, c_p_c);
1049
1050     for(pass=0;pass<=vr->maxpass;++pass) { // FIXME OPTIMIZE?
1051         uint_fast16_t voffset;
1052         uint_fast16_t partition_count;
1053         uint_fast16_t j_times_ptns_to_read;
1054
1055         voffset=vr->begin;
1056         for(partition_count=0;partition_count<ptns_to_read;) {  // SPEC        error
1057             if (!pass) {
1058                 for(j_times_ptns_to_read=0, j=0;j<ch_used;++j) {
1059                     if (!do_not_decode[j]) {
1060                         uint_fast32_t temp=get_vlc2(gb, vc->codebooks[vr->classbook].vlc.table,
1061                         V_NB_BITS, vc->codebooks[vr->classbook].maxdepth);
1062
1063                         AV_DEBUG("Classword: %d \n", temp);
1064
1065                         for(i=0;i<c_p_c;++i) {
1066                             uint_fast32_t temp2;
1067
1068                             temp2=temp/vr->classifications;
1069                             classifs[j_times_ptns_to_read+partition_count+c_p_c-1-i]=temp-temp2*vr->classifications;
1070                             temp=temp2;
1071                         }
1072                     }
1073                     j_times_ptns_to_read+=ptns_to_read;
1074                 }
1075             }
1076             for(i=0;(i<c_p_c) && (partition_count<ptns_to_read);++i) {
1077                 for(j_times_ptns_to_read=0, j=0;j<ch_used;++j) {
1078                     uint_fast16_t voffs;
1079
1080                     if (!do_not_decode[j]) {
1081                         uint_fast8_t vqclass=classifs[j_times_ptns_to_read+partition_count];
1082                         int_fast16_t vqbook=vr->books[vqclass][pass];
1083
1084                         if (vqbook>=0) {
1085                             uint_fast16_t coffs;
1086
1087                             if (vr->type==0) {
1088                                 uint_fast16_t step=vr->partition_size/vc->codebooks[vqbook].dimensions;
1089
1090                                 voffs=voffset+j*vlen;
1091                                 for(k=0;k<step;++k) {
1092                                     coffs=get_vlc2(gb, vc->codebooks[vqbook].vlc.table,
1093                                     V_NB_BITS, vc->codebooks[vr->classbook].maxdepth) * vc->codebooks[vqbook].dimensions;
1094                                     for(l=0;l<vc->codebooks[vqbook].dimensions;++l) {
1095                                         vec[voffs+k+l*step]+=vc->codebooks[vqbook].codevectors[coffs+l];  // FPMATH
1096                                     }
1097                                 }
1098                             }
1099                             else if (vr->type==1) {
1100                                 voffs=voffset+j*vlen;
1101                                 for(k=0;k<vr->partition_size/vc->codebooks[vqbook].dimensions;++k) {
1102                                     coffs=get_vlc2(gb, vc->codebooks[vqbook].vlc.table,
1103                                     V_NB_BITS, vc->codebooks[vr->classbook].maxdepth) * vc->codebooks[vqbook].dimensions;
1104                                     for(l=0;l<vc->codebooks[vqbook].dimensions;++l, ++voffs) {
1105                                         vec[voffs]+=vc->codebooks[vqbook].codevectors[coffs+l];  // FPMATH
1106
1107                                         AV_DEBUG(" pass %d offs: %d curr: %f change: %f cv offs.: %d  \n", pass, voffs, vec[voffs], vc->codebooks[vqbook].codevectors[coffs+l], coffs);
1108                                     }
1109                                 }
1110                             }
1111                             else if (vr->type==2 && ch==2) { // most frequent case optimized
1112                                 voffs=voffset;
1113
1114                                 for(k=0;k<vr->partition_size/vc->codebooks[vqbook].dimensions;++k) {
1115                                     coffs=get_vlc2(gb, vc->codebooks[vqbook].vlc.table,
1116                                     V_NB_BITS, vc->codebooks[vr->classbook].maxdepth) * vc->codebooks[vqbook].dimensions;
1117                                     for(l=0;l<vc->codebooks[vqbook].dimensions;++l, ++voffs) {
1118                                         vec[(voffs>>1)+((voffs&1) ? vlen : 0)]+=vc->codebooks[vqbook].codevectors[coffs+l];  // FPMATH
1119
1120                                         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], vc->codebooks[vqbook].codevectors[coffs+l], coffs, l);
1121                                     }
1122                                 }
1123
1124                             }
1125                             else if (vr->type==2) {
1126                                 voffs=voffset;
1127
1128                                 for(k=0;k<vr->partition_size/vc->codebooks[vqbook].dimensions;++k) {
1129                                     coffs=get_vlc2(gb, vc->codebooks[vqbook].vlc.table,
1130                                     V_NB_BITS, vc->codebooks[vr->classbook].maxdepth) * vc->codebooks[vqbook].dimensions;
1131                                     for(l=0;l<vc->codebooks[vqbook].dimensions;++l, ++voffs) {
1132                                         vec[voffs/ch+(voffs%ch)*vlen]+=vc->codebooks[vqbook].codevectors[coffs+l];  // FPMATH FIXME use if and counter instead of / and %
1133
1134                                         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], vc->codebooks[vqbook].codevectors[coffs+l], coffs, l);
1135                                     }
1136                                 }
1137                             } else {
1138                                 av_log(vc->avccontext, AV_LOG_ERROR, " Invalid residue type while residue decode?! \n");
1139                                 return 1;
1140                             }
1141                         }
1142                         j_times_ptns_to_read+=ptns_to_read;
1143                     }
1144                 }
1145                 ++partition_count;
1146                 voffset+=vr->partition_size;
1147             }
1148         }
1149     }
1150     return 0;
1151 }
1152
1153 // Decode the audio packet using the functions above
1154
1155 static int vorbis_parse_audio_packet(vorbis_context *vc) {
1156     GetBitContext *gb=&vc->gb;
1157
1158     uint_fast8_t previous_window=0,next_window=0;
1159     uint_fast8_t mode_number;
1160     uint_fast16_t blocksize;
1161     int_fast32_t i,j;
1162     uint_fast8_t no_residue[vc->audio_channels];
1163     uint_fast8_t do_not_decode[vc->audio_channels];
1164     vorbis_mapping *mapping;
1165     float *ch_res_ptr=vc->channel_residues;
1166     float *ch_floor_ptr=vc->channel_floors;
1167     uint_fast8_t res_chan[vc->audio_channels];
1168     uint_fast8_t res_num=0;
1169     int_fast16_t retlen=0;
1170     uint_fast16_t saved_start=0;
1171
1172     if (get_bits1(gb)) {
1173         av_log(vc->avccontext, AV_LOG_ERROR, "Not a Vorbis I audio packet.\n");
1174         return -1; // packet type not audio
1175     }
1176
1177     mode_number=get_bits(gb, ilog(vc->mode_count-1));
1178     mapping=&vc->mappings[vc->modes[mode_number].mapping];
1179
1180     AV_DEBUG(" Mode number: %d , mapping: %d , blocktype %d \n", mode_number, vc->modes[mode_number].mapping, vc->modes[mode_number].blockflag);
1181
1182     if (vc->modes[mode_number].blockflag) {
1183         previous_window=get_bits1(gb);
1184         next_window=get_bits1(gb);
1185     }
1186
1187     blocksize=vc->modes[mode_number].blockflag ? vc->blocksize_1 : vc->blocksize_0;
1188     memset(ch_res_ptr, 0, sizeof(float)*vc->audio_channels*blocksize/2); //FIXME can this be removed ?
1189     memset(ch_floor_ptr, 0, sizeof(float)*vc->audio_channels*blocksize/2); //FIXME can this be removed ?
1190
1191 // Decode floor(1)
1192
1193     for(i=0;i<vc->audio_channels;++i) {
1194         vorbis_floor *floor;
1195         if (mapping->submaps>1) {
1196             floor=&vc->floors[mapping->submap_floor[mapping->mux[i]]];
1197         } else {
1198             floor=&vc->floors[mapping->submap_floor[0]];
1199         }
1200
1201         no_residue[i]=vorbis_floor1_decode(vc, floor, ch_floor_ptr);
1202         ch_floor_ptr+=blocksize/2;
1203     }
1204
1205 // Nonzero vector propagate
1206
1207     for(i=mapping->coupling_steps-1;i>=0;--i) {
1208         if (!(no_residue[mapping->magnitude[i]] & no_residue[mapping->angle[i]])) {
1209             no_residue[mapping->magnitude[i]]=0;
1210             no_residue[mapping->angle[i]]=0;
1211         }
1212     }
1213
1214 // Decode residue
1215
1216     for(i=0;i<mapping->submaps;++i) {
1217         vorbis_residue *residue;
1218         uint_fast8_t ch=0;
1219
1220         for(j=0;j<vc->audio_channels;++j) {
1221             if ((mapping->submaps==1) || (i=mapping->mux[j])) {
1222                 res_chan[j]=res_num;
1223                 if (no_residue[j]) {
1224                     do_not_decode[ch]=1;
1225                 } else {
1226                     do_not_decode[ch]=0;
1227                 }
1228                 ++ch;
1229                 ++res_num;
1230             }
1231         }
1232         residue=&vc->residues[mapping->submap_residue[i]];
1233         vorbis_residue_decode(vc, residue, ch, do_not_decode, ch_res_ptr, blocksize/2);
1234
1235         ch_res_ptr+=ch*blocksize/2;
1236     }
1237
1238 // Inverse coupling
1239
1240     for(i=mapping->coupling_steps-1;i>=0;--i) { //warning: i has to be signed
1241         float *mag, *ang;
1242
1243         mag=vc->channel_residues+res_chan[mapping->magnitude[i]]*blocksize/2;
1244         ang=vc->channel_residues+res_chan[mapping->angle[i]]*blocksize/2;
1245         for(j=0;j<blocksize/2;++j) {
1246             float temp;
1247             if (mag[j]>0.0) {
1248                 if (ang[j]>0.0) {
1249                     ang[j]=mag[j]-ang[j];
1250                 } else {
1251                     temp=ang[j];
1252                     ang[j]=mag[j];
1253                     mag[j]+=temp;
1254                 }
1255             } else {
1256                 if (ang[j]>0.0) {
1257                     ang[j]+=mag[j];
1258                 } else {
1259                     temp=ang[j];
1260                     ang[j]=mag[j];
1261                     mag[j]-=temp;
1262                 }
1263             }
1264         }
1265     }
1266
1267 // Dotproduct
1268
1269     for(j=0, ch_floor_ptr=vc->channel_floors;j<vc->audio_channels;++j,ch_floor_ptr+=blocksize/2) {
1270         ch_res_ptr=vc->channel_residues+res_chan[j]*blocksize/2;
1271
1272         for(i=0;i<blocksize/2;++i) {
1273             ch_floor_ptr[i]*=ch_res_ptr[i]; //FPMATH
1274         }
1275     }
1276
1277 // MDCT, overlap/add, save data for next overlapping  FPMATH
1278
1279     for(j=0;j<vc->audio_channels;++j) {
1280         uint_fast8_t step=vc->audio_channels;
1281         uint_fast16_t k;
1282         float *saved=vc->saved+j*vc->blocksize_1/2;
1283         float *ret=vc->ret;
1284         const float *lwin=vc->lwin;
1285         const float *swin=vc->swin;
1286         float buf[blocksize];
1287         float buf_tmp[blocksize];
1288
1289         ch_floor_ptr=vc->channel_floors+j*blocksize/2;
1290
1291         saved_start=vc->saved_start;
1292
1293         ff_imdct_calc(vc->modes[mode_number].blockflag ? &vc->mdct1 : &vc->mdct0, buf, ch_floor_ptr, buf_tmp);
1294
1295         if (vc->modes[mode_number].blockflag) {
1296             // -- overlap/add
1297             if (previous_window) {
1298                 for(k=j, i=0;i<vc->blocksize_1/2;++i, k+=step) {
1299                     ret[k]=saved[i]+buf[i]*lwin[i];
1300                 }
1301                 retlen=vc->blocksize_1/2;
1302             } else {
1303                 for(k=j, i=0;i<vc->blocksize_0/2;++i, k+=step) {
1304                     ret[k]=saved[i]+buf[(vc->blocksize_1-vc->blocksize_0)/4+i]*swin[i];
1305                 }
1306                 for(i=0;i<(vc->blocksize_1-vc->blocksize_0)/4;++i, k+=step) {
1307                     ret[k]=buf[vc->blocksize_0/2+(vc->blocksize_1-vc->blocksize_0)/4+i];
1308                 }
1309                 retlen=vc->blocksize_0/2+(vc->blocksize_1-vc->blocksize_0)/4;
1310             }
1311             // -- save
1312             if (next_window) {
1313                 for(i=0;i<vc->blocksize_1/2;++i) {
1314                     saved[i]=buf[vc->blocksize_1/2+i]*lwin[vc->blocksize_1/2-1-i];
1315                 }
1316                 saved_start=0;
1317             } else {
1318                 saved_start=(vc->blocksize_1-vc->blocksize_0)/4;
1319                 for(i=0;i<saved_start;++i) {
1320                     saved[i]=buf[vc->blocksize_1/2+i];
1321                 }
1322                 for(i=0;i<vc->blocksize_0/2;++i) {
1323                     saved[saved_start+i]=buf[vc->blocksize_1/2+saved_start+i]*swin[vc->blocksize_0/2-1-i];
1324                 }
1325             }
1326         } else {
1327             // --overlap/add
1328             for(k=j, i=0;i<saved_start;++i, k+=step) {
1329                 ret[k]=saved[i];
1330             }
1331             for(i=0;i<vc->blocksize_0/2;++i, k+=step) {
1332                 ret[k]=saved[saved_start+i]+buf[i]*swin[i];
1333             }
1334             retlen=saved_start+vc->blocksize_0/2;
1335             // -- save
1336             for(i=0;i<vc->blocksize_0/2;++i) {
1337                 saved[i]=buf[vc->blocksize_0/2+i]*swin[vc->blocksize_0/2-1-i];
1338             }
1339             saved_start=0;
1340         }
1341     }
1342     vc->saved_start=saved_start;
1343
1344     return retlen*vc->audio_channels;
1345 }
1346
1347 // Return the decoded audio packet through the standard api
1348
1349 static int vorbis_decode_frame(AVCodecContext *avccontext,
1350                         void *data, int *data_size,
1351                         uint8_t *buf, int buf_size)
1352 {
1353     vorbis_context *vc = avccontext->priv_data ;
1354     GetBitContext *gb = &(vc->gb);
1355
1356     int_fast16_t i, len;
1357
1358     if(!buf_size){
1359         return 0;
1360     }
1361
1362     AV_DEBUG("packet length %d \n", buf_size);
1363
1364     init_get_bits(gb, buf, buf_size*8);
1365
1366     len=vorbis_parse_audio_packet(vc);
1367
1368     if (len<=0) {
1369         *data_size=0;
1370         return buf_size;
1371     }
1372
1373     if (!vc->first_frame) {
1374         vc->first_frame=1;
1375         *data_size=0;
1376         return buf_size ;
1377     }
1378
1379     AV_DEBUG("parsed %d bytes %d bits, returned %d samples (*ch*bits) \n", get_bits_count(gb)/8, get_bits_count(gb)%8, len);
1380
1381     for(i=0;i<len;++i) {
1382         int_fast32_t tmp;
1383
1384         tmp=vc->ret[i]*32768;
1385         if (tmp>32767) tmp=32767;
1386         if (tmp<-32768) tmp=-32768;
1387         ((int16_t*)data)[i]=tmp;
1388     }
1389     *data_size=len*2;
1390
1391     return buf_size ;
1392 }
1393
1394 // Close decoder
1395
1396 static int vorbis_decode_close(AVCodecContext *avccontext) {
1397     vorbis_context *vc = avccontext->priv_data;
1398
1399     vorbis_free(vc);
1400
1401     return 0 ;
1402 }
1403
1404 AVCodec vorbis_decoder = {
1405     "vorbis",
1406     CODEC_TYPE_AUDIO,
1407     CODEC_ID_VORBIS,
1408     sizeof(vorbis_context),
1409     vorbis_decode_init,
1410     NULL,
1411     vorbis_decode_close,
1412     vorbis_decode_frame,
1413 };
1414