add static keyword to some functions
[ffmpeg.git] / libavcodec / vorbis.c
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 static unsigned int nth_root(unsigned int x, unsigned int n) {   // x^(1/n)
60     unsigned int ret=0, i, j;
61
62     do {
63         ++ret;
64         for(i=0,j=ret;i<n-1;i++) j*=ret;
65     } while (j<=x);
66
67     return (ret-1);
68 }
69
70 static float vorbisfloat2float(uint_fast32_t val) {
71     double mant=val&0x1fffff;
72     long exp=(val&0x7fe00000L)>>21;
73     if (val&0x80000000) mant=-mant;
74     return(ldexp(mant, exp-20-768));
75 }
76
77
78 // Generate vlc codes from vorbis huffman code lengths
79
80 static int vorbis_len2vlc(vorbis_context *vc, uint_fast8_t *bits, uint_fast32_t *codes, uint_fast32_t num) {
81     uint_fast32_t exit_at_level[33]={404,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
82         0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
83
84     uint_fast8_t i,j;
85     uint_fast32_t code,p;
86
87 #ifdef V_DEBUG
88     GetBitContext gb;
89 #endif
90
91     for(p=0;(bits[p]==0) && (p<num);++p);
92     if (p==num) {
93 //        av_log(vc->avccontext, AV_LOG_INFO, "An empty codebook. Heh?! \n");
94         return 0;
95     }
96
97     codes[p]=0;
98     for(i=0;i<bits[p];++i) {
99         exit_at_level[i+1]=1<<i;
100     }
101
102 #ifdef V_DEBUG
103     av_log(vc->avccontext, AV_LOG_INFO, " %d. of %d code len %d code %d - ", p, num, bits[p], codes[p]);
104     init_get_bits(&gb, (uint_fast8_t *)&codes[p], bits[p]);
105     for(i=0;i<bits[p];++i) {
106         av_log(vc->avccontext, AV_LOG_INFO, "%s", get_bits1(&gb) ? "1" : "0");
107     }
108     av_log(vc->avccontext, AV_LOG_INFO, "\n");
109 #endif
110
111     ++p;
112
113     for(;p<num;++p) {
114         if (bits[p]==0) continue;
115         // find corresponding exit(node which the tree can grow further from)
116         for(i=bits[p];i>0;--i) {
117             if (exit_at_level[i]) break;
118         }
119         if (!i) return 1; // overspecified tree
120         code=exit_at_level[i];
121         exit_at_level[i]=0;
122         // construct code (append 0s to end) and introduce new exits
123         for(j=i+1;j<=bits[p];++j) {
124             exit_at_level[j]=code+(1<<(j-1));
125         }
126         codes[p]=code;
127
128 #ifdef V_DEBUG
129         av_log(vc->avccontext, AV_LOG_INFO, " %d. code len %d code %d - ", p, bits[p], codes[p]);
130         init_get_bits(&gb, (uint_fast8_t *)&codes[p], bits[p]);
131         for(i=0;i<bits[p];++i) {
132             av_log(vc->avccontext, AV_LOG_INFO, "%s", get_bits1(&gb) ? "1" : "0");
133         }
134         av_log(vc->avccontext, AV_LOG_INFO, "\n");
135 #endif
136
137     }
138
139     //FIXME no exits should be left (underspecified tree - ie. unused valid vlcs - not allowed by SPEC)
140
141     return 0;
142 }
143
144 // Free all allocated memory -----------------------------------------
145
146 static void vorbis_free(vorbis_context *vc) {
147     int_fast16_t i;
148
149     av_freep(&vc->channel_residues);
150     av_freep(&vc->channel_floors);
151     av_freep(&vc->saved);
152     av_freep(&vc->ret);
153     av_freep(&vc->buf);
154     av_freep(&vc->buf_tmp);
155
156     av_freep(&vc->residues);
157     av_freep(&vc->modes);
158
159     ff_mdct_end(&vc->mdct0);
160     ff_mdct_end(&vc->mdct1);
161
162     for(i=0;i<vc->codebook_count;++i) {
163         av_free(vc->codebooks[i].codevectors);
164         free_vlc(&vc->codebooks[i].vlc);
165     }
166     av_freep(&vc->codebooks);
167
168     for(i=0;i<vc->floor_count;++i) {
169         av_free(vc->floors[i].x_list);
170         av_free(vc->floors[i].x_list_order);
171         av_free(vc->floors[i].low_neighbour);
172         av_free(vc->floors[i].high_neighbour);
173     }
174     av_freep(&vc->floors);
175
176     for(i=0;i<vc->mapping_count;++i) {
177         av_free(vc->mappings[i].magnitude);
178         av_free(vc->mappings[i].angle);
179         av_free(vc->mappings[i].mux);
180     }
181     av_freep(&vc->mappings);
182 }
183
184 // Parse setup header -------------------------------------------------
185
186 // Process codebooks part
187
188 static int vorbis_parse_setup_hdr_codebooks(vorbis_context *vc) {
189     uint_fast16_t cb;
190     uint_fast8_t *tmp_vlc_bits;
191     uint_fast32_t *tmp_vlc_codes;
192     GetBitContext *gb=&vc->gb;
193
194     vc->codebook_count=get_bits(gb,8)+1;
195
196     AV_DEBUG(" Codebooks: %d \n", vc->codebook_count);
197
198     vc->codebooks=(vorbis_codebook *)av_mallocz(vc->codebook_count * sizeof(vorbis_codebook));
199     tmp_vlc_bits=(uint_fast8_t *)av_mallocz(V_MAX_VLCS * sizeof(uint_fast8_t));
200     tmp_vlc_codes=(uint_fast32_t *)av_mallocz(V_MAX_VLCS * sizeof(uint_fast32_t));
201
202     for(cb=0;cb<vc->codebook_count;++cb) {
203         vorbis_codebook *codebook_setup=&vc->codebooks[cb];
204         uint_fast8_t ordered;
205         uint_fast32_t t, used_entries=0;
206         uint_fast32_t entries;
207
208         AV_DEBUG(" %d. Codebook \n", cb);
209
210         if (get_bits(gb, 24)!=0x564342) {
211             av_log(vc->avccontext, AV_LOG_ERROR, " %"PRIdFAST16". Codebook setup data corrupt. \n", cb);
212             goto error;
213         }
214
215         codebook_setup->dimensions=get_bits(gb, 16);
216         if (codebook_setup->dimensions>16) {
217             av_log(vc->avccontext, AV_LOG_ERROR, " %"PRIdFAST16". Codebook's dimension is too large (%d). \n", cb, codebook_setup->dimensions);
218             goto error;
219         }
220         entries=get_bits(gb, 24);
221         if (entries>V_MAX_VLCS) {
222             av_log(vc->avccontext, AV_LOG_ERROR, " %"PRIdFAST16". Codebook has too many entries (%"PRIdFAST32"). \n", cb, entries);
223             goto error;
224         }
225
226         ordered=get_bits1(gb);
227
228         AV_DEBUG(" codebook_dimensions %d, codebook_entries %d \n", codebook_setup->dimensions, entries);
229
230         if (!ordered) {
231             uint_fast16_t ce;
232             uint_fast8_t flag;
233             uint_fast8_t sparse=get_bits1(gb);
234
235             AV_DEBUG(" not ordered \n");
236
237             if (sparse) {
238                 AV_DEBUG(" sparse \n");
239
240                 used_entries=0;
241                 for(ce=0;ce<entries;++ce) {
242                     flag=get_bits1(gb);
243                     if (flag) {
244                         tmp_vlc_bits[ce]=get_bits(gb, 5)+1;
245                         ++used_entries;
246                     }
247                     else tmp_vlc_bits[ce]=0;
248                 }
249             } else {
250                 AV_DEBUG(" not sparse \n");
251
252                 used_entries=entries;
253                 for(ce=0;ce<entries;++ce) {
254                     tmp_vlc_bits[ce]=get_bits(gb, 5)+1;
255                 }
256             }
257         } else {
258             uint_fast16_t current_entry=0;
259             uint_fast8_t current_length=get_bits(gb, 5)+1;
260
261             AV_DEBUG(" ordered, current length: %d \n", current_length);  //FIXME
262
263             used_entries=entries;
264             for(;current_entry<used_entries;++current_length) {
265                 uint_fast16_t i, number;
266
267                 AV_DEBUG(" number bits: %d ", ilog(entries - current_entry));
268
269                 number=get_bits(gb, ilog(entries - current_entry));
270
271                 AV_DEBUG(" number: %d \n", number);
272
273                 for(i=current_entry;i<number+current_entry;++i) {
274                     if (i<used_entries) tmp_vlc_bits[i]=current_length;
275                 }
276
277                 current_entry+=number;
278             }
279             if (current_entry>used_entries) {
280                 av_log(vc->avccontext, AV_LOG_ERROR, " More codelengths than codes in codebook. \n");
281                 goto error;
282             }
283         }
284
285         codebook_setup->lookup_type=get_bits(gb, 4);
286
287         AV_DEBUG(" lookup type: %d : %s \n", codebook_setup->lookup_type, codebook_setup->lookup_type ? "vq" : "no lookup" );
288
289 // If the codebook is used for (inverse) VQ, calculate codevectors.
290
291         if (codebook_setup->lookup_type==1) {
292             uint_fast16_t i, j, k;
293             uint_fast16_t codebook_lookup_values=nth_root(entries, codebook_setup->dimensions);
294             uint_fast16_t codebook_multiplicands[codebook_lookup_values];
295
296             float codebook_minimum_value=vorbisfloat2float(get_bits_long_le(gb, 32));
297             float codebook_delta_value=vorbisfloat2float(get_bits_long_le(gb, 32));
298             uint_fast8_t codebook_value_bits=get_bits(gb, 4)+1;
299             uint_fast8_t codebook_sequence_p=get_bits1(gb);
300
301             AV_DEBUG(" We expect %d numbers for building the codevectors. \n", codebook_lookup_values);
302             AV_DEBUG("  delta %f minmum %f \n", codebook_delta_value, codebook_minimum_value);
303
304             for(i=0;i<codebook_lookup_values;++i) {
305                 codebook_multiplicands[i]=get_bits(gb, codebook_value_bits);
306
307                 AV_DEBUG(" multiplicands*delta+minmum : %e \n", (float)codebook_multiplicands[i]*codebook_delta_value+codebook_minimum_value);
308                 AV_DEBUG(" multiplicand %d \n", codebook_multiplicands[i]);
309             }
310
311 // Weed out unused vlcs and build codevector vector
312             codebook_setup->codevectors=(float *)av_mallocz(used_entries*codebook_setup->dimensions * sizeof(float));
313             for(j=0, i=0;i<entries;++i) {
314                 uint_fast8_t dim=codebook_setup->dimensions;
315
316                 if (tmp_vlc_bits[i]) {
317                     float last=0.0;
318                     uint_fast32_t lookup_offset=i;
319
320 #ifdef V_DEBUG
321                     av_log(vc->avccontext, AV_LOG_INFO, "Lookup offset %d ,", i);
322 #endif
323
324                     for(k=0;k<dim;++k) {
325                         uint_fast32_t multiplicand_offset = lookup_offset % codebook_lookup_values;
326                         codebook_setup->codevectors[j*dim+k]=codebook_multiplicands[multiplicand_offset]*codebook_delta_value+codebook_minimum_value+last;
327                         if (codebook_sequence_p) {
328                             last=codebook_setup->codevectors[j*dim+k];
329                         }
330                         lookup_offset/=codebook_lookup_values;
331                     }
332                     tmp_vlc_bits[j]=tmp_vlc_bits[i];
333
334 #ifdef V_DEBUG
335                     av_log(vc->avccontext, AV_LOG_INFO, "real lookup offset %d, vector: ", j);
336                     for(k=0;k<dim;++k) {
337                         av_log(vc->avccontext, AV_LOG_INFO, " %f ", codebook_setup->codevectors[j*dim+k]);
338                     }
339                     av_log(vc->avccontext, AV_LOG_INFO, "\n");
340 #endif
341
342                     ++j;
343                 }
344             }
345             if (j!=used_entries) {
346                 av_log(vc->avccontext, AV_LOG_ERROR, "Bug in codevector vector building code. \n");
347                 goto error;
348             }
349             entries=used_entries;
350         }
351         else if (codebook_setup->lookup_type>=2) {
352             av_log(vc->avccontext, AV_LOG_ERROR, "Codebook lookup type not supported. \n");
353             goto error;
354         }
355
356 // Initialize VLC table
357         if (vorbis_len2vlc(vc, tmp_vlc_bits, tmp_vlc_codes, entries)) {
358             av_log(vc->avccontext, AV_LOG_ERROR, " Invalid code lengths while generating vlcs. \n");
359             goto error;
360         }
361         codebook_setup->maxdepth=0;
362         for(t=0;t<entries;++t)
363             if (tmp_vlc_bits[t]>=codebook_setup->maxdepth) codebook_setup->maxdepth=tmp_vlc_bits[t];
364
365         if(codebook_setup->maxdepth > 3*V_NB_BITS) codebook_setup->nb_bits=V_NB_BITS2;
366         else                                       codebook_setup->nb_bits=V_NB_BITS;
367
368         codebook_setup->maxdepth=(codebook_setup->maxdepth+codebook_setup->nb_bits-1)/codebook_setup->nb_bits;
369
370         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)) {
371             av_log(vc->avccontext, AV_LOG_ERROR, " Error generating vlc tables. \n");
372             goto error;
373         }
374     }
375
376     av_free(tmp_vlc_bits);
377     av_free(tmp_vlc_codes);
378     return 0;
379
380 // Error:
381 error:
382     av_free(tmp_vlc_bits);
383     av_free(tmp_vlc_codes);
384     return 1;
385 }
386
387 // Process time domain transforms part (unused in Vorbis I)
388
389 static int vorbis_parse_setup_hdr_tdtransforms(vorbis_context *vc) {
390     GetBitContext *gb=&vc->gb;
391     uint_fast8_t i;
392     uint_fast8_t vorbis_time_count=get_bits(gb, 6)+1;
393
394     for(i=0;i<vorbis_time_count;++i) {
395         uint_fast16_t vorbis_tdtransform=get_bits(gb, 16);
396
397         AV_DEBUG(" Vorbis time domain transform %d: %d \n", vorbis_time_count, vorbis_tdtransform);
398
399         if (vorbis_tdtransform) {
400             av_log(vc->avccontext, AV_LOG_ERROR, "Vorbis time domain transform data nonzero. \n");
401             return 1;
402         }
403     }
404     return 0;
405 }
406
407 // Process floors part - only floor type 1 is supported
408
409 static int vorbis_parse_setup_hdr_floors(vorbis_context *vc) {
410     GetBitContext *gb=&vc->gb;
411     uint_fast16_t i,j,k;
412
413     vc->floor_count=get_bits(gb, 6)+1;
414
415     vc->floors=(vorbis_floor *)av_mallocz(vc->floor_count * sizeof(vorbis_floor));
416
417     for (i=0;i<vc->floor_count;++i) {
418         vorbis_floor *floor_setup=&vc->floors[i];
419
420         floor_setup->floor_type=get_bits(gb, 16);
421
422         AV_DEBUG(" %d. floor type %d \n", i, floor_setup->floor_type);
423
424         if (floor_setup->floor_type==1) {
425             uint_fast8_t maximum_class=0;
426             uint_fast8_t rangebits;
427             uint_fast16_t floor1_values=2;
428
429             floor_setup->partitions=get_bits(gb, 5);
430
431             AV_DEBUG(" %d.floor: %d partitions \n", i, floor_setup->partitions);
432
433             for(j=0;j<floor_setup->partitions;++j) {
434                 floor_setup->partition_class[j]=get_bits(gb, 4);
435                 if (floor_setup->partition_class[j]>maximum_class) maximum_class=floor_setup->partition_class[j];
436
437                 AV_DEBUG(" %d. floor %d partition class %d \n", i, j, floor_setup->partition_class[j]);
438
439             }
440
441             AV_DEBUG(" maximum class %d \n", maximum_class);
442
443             floor_setup->maximum_class=maximum_class;
444
445             for(j=0;j<=maximum_class;++j) {
446                 floor_setup->class_dimensions[j]=get_bits(gb, 3)+1;
447                 floor_setup->class_subclasses[j]=get_bits(gb, 2);
448
449                 AV_DEBUG(" %d floor %d class dim: %d subclasses %d \n", i, j, floor_setup->class_dimensions[j], floor_setup->class_subclasses[j]);
450
451                 if (floor_setup->class_subclasses[j]) {
452                     floor_setup->class_masterbook[j]=get_bits(gb, 8);
453
454                     AV_DEBUG("   masterbook: %d \n", floor_setup->class_masterbook[j]);
455                 }
456
457                 for(k=0;k<(1<<floor_setup->class_subclasses[j]);++k) {
458                     floor_setup->subclass_books[j][k]=get_bits(gb, 8)-1;
459
460                     AV_DEBUG("    book %d. : %d \n", k, floor_setup->subclass_books[j][k]);
461                 }
462             }
463
464             floor_setup->multiplier=get_bits(gb, 2)+1;
465             floor_setup->x_list_dim=2;
466
467             for(j=0;j<floor_setup->partitions;++j) {
468                 floor_setup->x_list_dim+=floor_setup->class_dimensions[floor_setup->partition_class[j]];
469             }
470
471             floor_setup->x_list=(uint_fast16_t *)av_mallocz(floor_setup->x_list_dim * sizeof(uint_fast16_t));
472             floor_setup->x_list_order=(uint_fast16_t *)av_mallocz(floor_setup->x_list_dim * sizeof(uint_fast16_t));
473             floor_setup->low_neighbour=(uint_fast16_t *)av_mallocz(floor_setup->x_list_dim * sizeof(uint_fast16_t));
474             floor_setup->high_neighbour=(uint_fast16_t *)av_mallocz(floor_setup->x_list_dim * sizeof(uint_fast16_t));
475
476
477             rangebits=get_bits(gb, 4);
478             floor_setup->x_list[0] = 0;
479             floor_setup->x_list[1] = (1<<rangebits);
480
481             for(j=0;j<floor_setup->partitions;++j) {
482                 for(k=0;k<floor_setup->class_dimensions[floor_setup->partition_class[j]];++k,++floor1_values) {
483                     floor_setup->x_list[floor1_values]=get_bits(gb, rangebits);
484
485                     AV_DEBUG(" %d. floor1 Y coord. %d \n", floor1_values, floor_setup->x_list[floor1_values]);
486                 }
487             }
488
489 // Precalculate order of x coordinates - needed for decode
490
491             for(k=0;k<floor_setup->x_list_dim;++k) {
492                 floor_setup->x_list_order[k]=k;
493             }
494
495             for(k=0;k<floor_setup->x_list_dim-1;++k) {   // FIXME optimize sorting ?
496                 for(j=k+1;j<floor_setup->x_list_dim;++j) {
497                     if(floor_setup->x_list[floor_setup->x_list_order[k]]>floor_setup->x_list[floor_setup->x_list_order[j]]) {
498                         uint_fast16_t tmp=floor_setup->x_list_order[k];
499                         floor_setup->x_list_order[k]=floor_setup->x_list_order[j];
500                         floor_setup->x_list_order[j]=tmp;
501                     }
502                 }
503             }
504
505 // Precalculate low and high neighbours
506
507             for(k=2;k<floor_setup->x_list_dim;++k) {
508                 floor_setup->low_neighbour[k]=0;
509                 floor_setup->high_neighbour[k]=1;  // correct according to SPEC requirements
510
511                 for (j=0;j<k;++j) {
512                     if ((floor_setup->x_list[j]<floor_setup->x_list[k]) &&
513                       (floor_setup->x_list[j]>floor_setup->x_list[floor_setup->low_neighbour[k]])) {
514                         floor_setup->low_neighbour[k]=j;
515                     }
516                     if ((floor_setup->x_list[j]>floor_setup->x_list[k]) &&
517                       (floor_setup->x_list[j]<floor_setup->x_list[floor_setup->high_neighbour[k]])) {
518                         floor_setup->high_neighbour[k]=j;
519                     }
520                 }
521             }
522         }
523         else {
524             av_log(vc->avccontext, AV_LOG_ERROR, "Only floor type 1 supported. \n");
525             return 1;
526         }
527     }
528     return 0;
529 }
530
531 // Process residues part
532
533 static int vorbis_parse_setup_hdr_residues(vorbis_context *vc){
534     GetBitContext *gb=&vc->gb;
535     uint_fast8_t i, j, k;
536
537     vc->residue_count=get_bits(gb, 6)+1;
538     vc->residues=(vorbis_residue *)av_mallocz(vc->residue_count * sizeof(vorbis_residue));
539
540     AV_DEBUG(" There are %d residues. \n", vc->residue_count);
541
542     for(i=0;i<vc->residue_count;++i) {
543         vorbis_residue *res_setup=&vc->residues[i];
544         uint_fast8_t cascade[64];
545         uint_fast8_t high_bits;
546         uint_fast8_t low_bits;
547
548         res_setup->type=get_bits(gb, 16);
549
550         AV_DEBUG(" %d. residue type %d \n", i, res_setup->type);
551
552         res_setup->begin=get_bits(gb, 24);
553         res_setup->end=get_bits(gb, 24);
554         res_setup->partition_size=get_bits(gb, 24)+1;
555         res_setup->classifications=get_bits(gb, 6)+1;
556         res_setup->classbook=get_bits(gb, 8);
557
558         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,
559           res_setup->classifications, res_setup->classbook);
560
561         for(j=0;j<res_setup->classifications;++j) {
562             high_bits=0;
563             low_bits=get_bits(gb, 3);
564             if (get_bits1(gb)) {
565                 high_bits=get_bits(gb, 5);
566             }
567             cascade[j]=(high_bits<<3)+low_bits;
568
569             AV_DEBUG("     %d class casscade depth: %d \n", j, ilog(cascade[j]));
570         }
571
572         res_setup->maxpass=0;
573         for(j=0;j<res_setup->classifications;++j) {
574             for(k=0;k<8;++k) {
575                 if (cascade[j]&(1<<k)) {
576                         res_setup->books[j][k]=get_bits(gb, 8);
577
578                     AV_DEBUG("     %d class casscade depth %d book: %d \n", j, k, res_setup->books[j][k]);
579
580                     if (k>res_setup->maxpass) {
581                         res_setup->maxpass=k;
582                     }
583                 } else {
584                     res_setup->books[j][k]=-1;
585                 }
586             }
587         }
588     }
589     return 0;
590 }
591
592 // Process mappings part
593
594 static int vorbis_parse_setup_hdr_mappings(vorbis_context *vc) {
595     GetBitContext *gb=&vc->gb;
596     uint_fast8_t i, j;
597
598     vc->mapping_count=get_bits(gb, 6)+1;
599     vc->mappings=(vorbis_mapping *)av_mallocz(vc->mapping_count * sizeof(vorbis_mapping));
600
601     AV_DEBUG(" There are %d mappings. \n", vc->mapping_count);
602
603     for(i=0;i<vc->mapping_count;++i) {
604         vorbis_mapping *mapping_setup=&vc->mappings[i];
605
606         if (get_bits(gb, 16)) {
607             av_log(vc->avccontext, AV_LOG_ERROR, "Other mappings than type 0 are not compliant with the Vorbis I specification. \n");
608             return 1;
609         }
610         if (get_bits1(gb)) {
611             mapping_setup->submaps=get_bits(gb, 4)+1;
612         } else {
613             mapping_setup->submaps=1;
614         }
615
616         if (get_bits1(gb)) {
617             mapping_setup->coupling_steps=get_bits(gb, 8)+1;
618             mapping_setup->magnitude=(uint_fast8_t *)av_mallocz(mapping_setup->coupling_steps * sizeof(uint_fast8_t));
619             mapping_setup->angle=(uint_fast8_t *)av_mallocz(mapping_setup->coupling_steps * sizeof(uint_fast8_t));
620             for(j=0;j<mapping_setup->coupling_steps;++j) {
621                 mapping_setup->magnitude[j]=get_bits(gb, ilog(vc->audio_channels-1));
622                 mapping_setup->angle[j]=get_bits(gb, ilog(vc->audio_channels-1));
623                 // FIXME: sanity checks
624             }
625         } else {
626             mapping_setup->coupling_steps=0;
627         }
628
629         AV_DEBUG("   %d mapping coupling steps: %d \n", i, mapping_setup->coupling_steps);
630
631         if(get_bits(gb, 2)) {
632             av_log(vc->avccontext, AV_LOG_ERROR, "%d. mapping setup data invalid. \n", i);
633             return 1; // following spec.
634         }
635
636         if (mapping_setup->submaps>1) {
637             mapping_setup->mux=(uint_fast8_t *)av_mallocz(vc->audio_channels * sizeof(uint_fast8_t));
638             for(j=0;j<vc->audio_channels;++j) {
639                 mapping_setup->mux[j]=get_bits(gb, 4);
640             }
641         }
642
643         for(j=0;j<mapping_setup->submaps;++j) {
644             get_bits(gb, 8); // FIXME check?
645             mapping_setup->submap_floor[j]=get_bits(gb, 8);
646             mapping_setup->submap_residue[j]=get_bits(gb, 8);
647
648             AV_DEBUG("   %d mapping %d submap : floor %d, residue %d \n", i, j, mapping_setup->submap_floor[j], mapping_setup->submap_residue[j]);
649         }
650     }
651     return 0;
652 }
653
654 // Process modes part
655
656 static int vorbis_parse_setup_hdr_modes(vorbis_context *vc) {
657     GetBitContext *gb=&vc->gb;
658     uint_fast8_t i;
659
660     vc->mode_count=get_bits(gb, 6)+1;
661     vc->modes=(vorbis_mode *)av_mallocz(vc->mode_count * sizeof(vorbis_mode));
662
663     AV_DEBUG(" There are %d modes.\n", vc->mode_count);
664
665     for(i=0;i<vc->mode_count;++i) {
666         vorbis_mode *mode_setup=&vc->modes[i];
667
668         mode_setup->blockflag=get_bits(gb, 1);
669         mode_setup->windowtype=get_bits(gb, 16); //FIXME check
670         mode_setup->transformtype=get_bits(gb, 16); //FIXME check
671         mode_setup->mapping=get_bits(gb, 8); //FIXME check
672
673         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);
674     }
675     return 0;
676 }
677
678 // Process the whole setup header using the functions above
679
680 static int vorbis_parse_setup_hdr(vorbis_context *vc) {
681     GetBitContext *gb=&vc->gb;
682
683     if ((get_bits(gb, 8)!='v') || (get_bits(gb, 8)!='o') ||
684     (get_bits(gb, 8)!='r') || (get_bits(gb, 8)!='b') ||
685     (get_bits(gb, 8)!='i') || (get_bits(gb, 8)!='s')) {
686         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (no vorbis signature). \n");
687         return 1;
688     }
689
690     if (vorbis_parse_setup_hdr_codebooks(vc)) {
691         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (codebooks). \n");
692         return 2;
693     }
694     if (vorbis_parse_setup_hdr_tdtransforms(vc)) {
695         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (time domain transforms). \n");
696         return 3;
697     }
698     if (vorbis_parse_setup_hdr_floors(vc)) {
699         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (floors). \n");
700         return 4;
701     }
702     if (vorbis_parse_setup_hdr_residues(vc)) {
703         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (residues). \n");
704         return 5;
705     }
706     if (vorbis_parse_setup_hdr_mappings(vc)) {
707         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (mappings). \n");
708         return 6;
709     }
710     if (vorbis_parse_setup_hdr_modes(vc)) {
711         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (modes). \n");
712         return 7;
713     }
714     if (!get_bits1(gb)) {
715         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (framing flag). \n");
716         return 8; // framing flag bit unset error
717     }
718
719     return 0;
720 }
721
722 // Process the identification header
723
724 static int vorbis_parse_id_hdr(vorbis_context *vc){
725     GetBitContext *gb=&vc->gb;
726     uint_fast8_t bl0, bl1;
727     const float *vwin[8]={ vwin64, vwin128, vwin256, vwin512, vwin1024, vwin2048, vwin4096, vwin8192 };
728
729     if ((get_bits(gb, 8)!='v') || (get_bits(gb, 8)!='o') ||
730     (get_bits(gb, 8)!='r') || (get_bits(gb, 8)!='b') ||
731     (get_bits(gb, 8)!='i') || (get_bits(gb, 8)!='s')) {
732         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis id header packet corrupt (no vorbis signature). \n");
733         return 1;
734     }
735
736     vc->version=get_bits_long_le(gb, 32);    //FIXME check 0
737     vc->audio_channels=get_bits(gb, 8);   //FIXME check >0
738     vc->audio_samplerate=get_bits_long_le(gb, 32);   //FIXME check >0
739     vc->bitrate_maximum=get_bits_long_le(gb, 32);
740     vc->bitrate_nominal=get_bits_long_le(gb, 32);
741     vc->bitrate_minimum=get_bits_long_le(gb, 32);
742     bl0=get_bits(gb, 4);
743     bl1=get_bits(gb, 4);
744     vc->blocksize_0=(1<<bl0);
745     vc->blocksize_1=(1<<bl1);
746     if (bl0>13 || bl0<6 || bl1>13 || bl1<6) {
747         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis id header packet corrupt (illegal blocksize). \n");
748         return 3;
749     }
750     vc->swin=vwin[bl0-6];
751     vc->lwin=vwin[bl1-6];
752
753     if ((get_bits1(gb)) == 0) {
754         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis id header packet corrupt (framing flag not set). \n");
755         return 2;
756     }
757
758     vc->channel_residues=(float *)av_malloc((vc->blocksize_1/2)*vc->audio_channels * sizeof(float));
759     vc->channel_floors=(float *)av_malloc((vc->blocksize_1/2)*vc->audio_channels * sizeof(float));
760     vc->saved=(float *)av_malloc((vc->blocksize_1/2)*vc->audio_channels * sizeof(float));
761     vc->ret=(float *)av_malloc((vc->blocksize_1/2)*vc->audio_channels * sizeof(float));
762     vc->buf=(float *)av_malloc(vc->blocksize_1 * sizeof(float));
763     vc->buf_tmp=(float *)av_malloc(vc->blocksize_1 * sizeof(float));
764     vc->saved_start=0;
765
766     ff_mdct_init(&vc->mdct0, bl0, 1);
767     ff_mdct_init(&vc->mdct1, bl1, 1);
768
769     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 ",
770             vc->version, vc->audio_channels, vc->audio_samplerate, vc->bitrate_maximum, vc->bitrate_nominal, vc->bitrate_minimum, vc->blocksize_0, vc->blocksize_1);
771
772 /*
773     BLK=vc->blocksize_0;
774     for(i=0;i<BLK/2;++i) {
775         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)));
776     }
777 */
778
779     return 0;
780 }
781
782 // Process the extradata using the functions above (identification header, setup header)
783
784 static int vorbis_decode_init(AVCodecContext *avccontext) {
785     vorbis_context *vc = avccontext->priv_data ;
786     uint8_t *headers = avccontext->extradata;
787     int headers_len=avccontext->extradata_size;
788     uint8_t *header_start[3];
789     int header_len[3];
790     GetBitContext *gb = &(vc->gb);
791     int i, j, hdr_type;
792
793     vc->avccontext = avccontext;
794
795     if (!headers_len) {
796         av_log(avccontext, AV_LOG_ERROR, "Extradata corrupt.\n");
797         return -1;
798     }
799
800     if(headers[0] == 0 && headers[1] == 30) {
801         for(i = 0; i < 3; i++){
802             header_len[i] = *headers++ << 8;
803             header_len[i] += *headers++;
804             header_start[i] = headers;
805             headers += header_len[i];
806         }
807     } else if(headers[0] == 2) {
808         for(j=1,i=0;i<2;++i, ++j) {
809             header_len[i]=0;
810             while(j<headers_len && headers[j]==0xff) {
811                 header_len[i]+=0xff;
812                 ++j;
813             }
814             if (j>=headers_len) {
815                 av_log(avccontext, AV_LOG_ERROR, "Extradata corrupt.\n");
816                 return -1;
817             }
818             header_len[i]+=headers[j];
819         }
820         header_len[2]=headers_len-header_len[0]-header_len[1]-j;
821         headers+=j;
822         header_start[0] = headers;
823         header_start[1] = header_start[0] + header_len[0];
824         header_start[2] = header_start[1] + header_len[1];
825     } else {
826         av_log(avccontext, AV_LOG_ERROR, "Extradata corrupt.\n");
827         return -1;
828     }
829
830     init_get_bits(gb, header_start[0], header_len[0]*8);
831     hdr_type=get_bits(gb, 8);
832     if (hdr_type!=1) {
833         av_log(avccontext, AV_LOG_ERROR, "First header is not the id header.\n");
834         return -1;
835     }
836     if (vorbis_parse_id_hdr(vc)) {
837         av_log(avccontext, AV_LOG_ERROR, "Id header corrupt.\n");
838         vorbis_free(vc);
839         return -1;
840     }
841
842     init_get_bits(gb, header_start[2], header_len[2]*8);
843     hdr_type=get_bits(gb, 8);
844     if (hdr_type!=5) {
845         av_log(avccontext, AV_LOG_ERROR, "Third header is not the setup header.\n");
846         return -1;
847     }
848     if (vorbis_parse_setup_hdr(vc)) {
849         av_log(avccontext, AV_LOG_ERROR, "Setup header corrupt.\n");
850         vorbis_free(vc);
851         return -1;
852     }
853
854     avccontext->channels = vc->audio_channels;
855     avccontext->sample_rate = vc->audio_samplerate;
856
857     return 0 ;
858 }
859
860 // Decode audiopackets -------------------------------------------------
861
862 // Read and decode floor (type 1 only)
863
864 static uint_fast8_t vorbis_floor1_decode(vorbis_context *vc, vorbis_floor *vf, float *vec) {
865     GetBitContext *gb=&vc->gb;
866     uint_fast16_t range_v[4]={ 256, 128, 86, 64 };
867     uint_fast16_t range=range_v[vf->multiplier-1];
868     uint_fast16_t floor1_Y[vf->x_list_dim];
869     uint_fast16_t floor1_Y_final[vf->x_list_dim];
870     uint_fast8_t floor1_flag[vf->x_list_dim];
871     uint_fast8_t class_;
872     uint_fast8_t cdim;
873     uint_fast8_t cbits;
874     uint_fast8_t csub;
875     uint_fast8_t cval;
876     int_fast16_t book;
877     uint_fast16_t offset;
878     uint_fast16_t i,j;
879     uint_fast16_t *floor_x_sort=vf->x_list_order;
880     /*u*/int_fast16_t adx, ady, off, predicted; // WTF ? dy/adx= (unsigned)dy/adx ?
881     int_fast16_t dy, err;
882     uint_fast16_t lx,hx, ly, hy=0;
883
884
885     if (!get_bits1(gb)) return 1; // silence
886
887 // Read values (or differences) for the floor's points
888
889     floor1_Y[0]=get_bits(gb, ilog(range-1));
890     floor1_Y[1]=get_bits(gb, ilog(range-1));
891
892     AV_DEBUG("floor 0 Y %d floor 1 Y %d \n", floor1_Y[0], floor1_Y[1]);
893
894     offset=2;
895     for(i=0;i<vf->partitions;++i) {
896         class_=vf->partition_class[i];
897         cdim=vf->class_dimensions[class_];
898         cbits=vf->class_subclasses[class_];
899         csub=(1<<cbits)-1;
900         cval=0;
901
902         AV_DEBUG("Cbits %d \n", cbits);
903
904         if (cbits) { // this reads all subclasses for this partition's class
905             cval=get_vlc2(gb, vc->codebooks[vf->class_masterbook[class_]].vlc.table,
906             vc->codebooks[vf->class_masterbook[class_]].nb_bits, 3);
907         }
908
909         for(j=0;j<cdim;++j) {
910             book=vf->subclass_books[class_][cval & csub];
911
912             AV_DEBUG("book %d Cbits %d cval %d  bits:%d \n", book, cbits, cval, get_bits_count(gb));
913
914             cval=cval>>cbits;
915             if (book>0) {
916                 floor1_Y[offset+j]=get_vlc2(gb, vc->codebooks[book].vlc.table,
917                 vc->codebooks[book].nb_bits, 3);
918             } else {
919                 floor1_Y[offset+j]=0;
920             }
921
922             AV_DEBUG(" floor(%d) = %d \n", vf->x_list[offset+j], floor1_Y[offset+j]);
923         }
924         offset+=cdim;
925     }
926
927 // Amplitude calculation from the differences
928
929     floor1_flag[0]=1;
930     floor1_flag[1]=1;
931     floor1_Y_final[0]=floor1_Y[0];
932     floor1_Y_final[1]=floor1_Y[1];
933
934     for(i=2;i<vf->x_list_dim;++i) {
935         uint_fast16_t val, highroom, lowroom, room;
936         uint_fast16_t high_neigh_offs;
937         uint_fast16_t low_neigh_offs;
938
939         low_neigh_offs=vf->low_neighbour[i];
940         high_neigh_offs=vf->high_neighbour[i];
941         dy=floor1_Y_final[high_neigh_offs]-floor1_Y_final[low_neigh_offs];  // render_point begin
942         adx=vf->x_list[high_neigh_offs]-vf->x_list[low_neigh_offs];
943         ady= ABS(dy);
944         err=ady*(vf->x_list[i]-vf->x_list[low_neigh_offs]);
945         off=err/adx;
946         if (dy<0) {
947             predicted=floor1_Y_final[low_neigh_offs]-off;
948         } else {
949             predicted=floor1_Y_final[low_neigh_offs]+off;
950         } // render_point end
951
952         val=floor1_Y[i];
953         highroom=range-predicted;
954         lowroom=predicted;
955         if (highroom < lowroom) {
956             room=highroom*2;
957         } else {
958             room=lowroom*2;   // SPEC mispelling
959         }
960         if (val) {
961             floor1_flag[low_neigh_offs]=1;
962             floor1_flag[high_neigh_offs]=1;
963             floor1_flag[i]=1;
964             if (val>=room) {
965                 if (highroom > lowroom) {
966                     floor1_Y_final[i]=val-lowroom+predicted;
967                 } else {
968                     floor1_Y_final[i]=predicted-val+highroom-1;
969                 }
970             } else {
971                 if (val & 1) {
972                     floor1_Y_final[i]=predicted-(val+1)/2;
973                 } else {
974                     floor1_Y_final[i]=predicted+val/2;
975                 }
976             }
977         } else {
978             floor1_flag[i]=0;
979             floor1_Y_final[i]=predicted;
980         }
981
982         AV_DEBUG(" Decoded floor(%d) = %d / val %d \n", vf->x_list[i], floor1_Y_final[i], val);
983     }
984
985 // Curve synth - connect the calculated dots and convert from dB scale FIXME optimize ?
986
987     hx=0;
988     lx=0;
989     ly=floor1_Y_final[0]*vf->multiplier;  // conforms to SPEC
990
991     vec[0]=floor1_inverse_db_table[ly];
992
993     for(i=1;i<vf->x_list_dim;++i) {
994         AV_DEBUG(" Looking at post %d \n", i);
995
996         if (floor1_flag[floor_x_sort[i]]) {   // SPEC mispelled
997             int_fast16_t x, y, dy, base, sy; // if uncommented: dy = -32 adx = 2  base = 2blablabla ?????
998
999             hy=floor1_Y_final[floor_x_sort[i]]*vf->multiplier;
1000             hx=vf->x_list[floor_x_sort[i]];
1001
1002             dy=hy-ly;
1003             adx=hx-lx;
1004             ady= (dy<0) ? -dy:dy;//ABS(dy);
1005             base=dy/adx;
1006
1007             AV_DEBUG(" dy %d  adx %d base %d = %d \n", dy, adx, base, dy/adx);
1008
1009             x=lx;
1010             y=ly;
1011             err=0;
1012             if (dy<0) {
1013                 sy=base-1;
1014             } else {
1015                 sy=base+1;
1016             }
1017             ady=ady-(base<0 ? -base : base)*adx;
1018             vec[x]=floor1_inverse_db_table[y];
1019
1020             AV_DEBUG(" vec[ %d ] = %d \n", x, y);
1021
1022             for(x=lx+1;(x<hx) && (x<vf->x_list[1]);++x) {
1023                 err+=ady;
1024                 if (err>=adx) {
1025                     err-=adx;
1026                     y+=sy;
1027                 } else {
1028                     y+=base;
1029                 }
1030                 vec[x]=floor1_inverse_db_table[y];
1031
1032                 AV_DEBUG(" vec[ %d ] = %d \n", x, y);
1033             }
1034
1035 /*            for(j=1;j<hx-lx+1;++j) {  // iterating render_point
1036                 dy=hy-ly;
1037                 adx=hx-lx;
1038                 ady= dy<0 ? -dy : dy;
1039                 err=ady*j;
1040                 off=err/adx;
1041                 if (dy<0) {
1042                     predicted=ly-off;
1043                 } else {
1044                     predicted=ly+off;
1045                 }
1046                 if (lx+j < vf->x_list[1]) {
1047                     vec[lx+j]=floor1_inverse_db_table[predicted];
1048                 }
1049             }*/
1050
1051             lx=hx;
1052             ly=hy;
1053         }
1054     }
1055
1056     if (hx<vf->x_list[1]) {
1057         for(i=hx;i<vf->x_list[1];++i) {
1058             vec[i]=floor1_inverse_db_table[hy];
1059         }
1060     }
1061
1062     AV_DEBUG(" Floor decoded\n");
1063
1064     return 0;
1065 }
1066
1067 // Read and decode residue
1068
1069 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) {
1070     GetBitContext *gb=&vc->gb;
1071     uint_fast8_t c_p_c=vc->codebooks[vr->classbook].dimensions;
1072     uint_fast16_t n_to_read=vr->end-vr->begin;
1073     uint_fast16_t ptns_to_read=n_to_read/vr->partition_size;
1074     uint_fast8_t classifs[ptns_to_read*vc->audio_channels];
1075     uint_fast8_t pass;
1076     uint_fast8_t ch_used;
1077     uint_fast8_t i,j,l;
1078     uint_fast16_t k;
1079
1080     if (vr->type==2) {
1081         for(j=1;j<ch;++j) {
1082                 do_not_decode[0]&=do_not_decode[j];  // FIXME - clobbering input
1083         }
1084         if (do_not_decode[0]) return 0;
1085         ch_used=1;
1086     } else {
1087         ch_used=ch;
1088     }
1089
1090     AV_DEBUG(" residue type 0/1/2 decode begin, ch: %d  cpc %d  \n", ch, c_p_c);
1091
1092     for(pass=0;pass<=vr->maxpass;++pass) { // FIXME OPTIMIZE?
1093         uint_fast16_t voffset;
1094         uint_fast16_t partition_count;
1095         uint_fast16_t j_times_ptns_to_read;
1096
1097         voffset=vr->begin;
1098         for(partition_count=0;partition_count<ptns_to_read;) {  // SPEC        error
1099             if (!pass) {
1100                 for(j_times_ptns_to_read=0, j=0;j<ch_used;++j) {
1101                     if (!do_not_decode[j]) {
1102                         uint_fast32_t temp=get_vlc2(gb, vc->codebooks[vr->classbook].vlc.table,
1103                         vc->codebooks[vr->classbook].nb_bits, 3);
1104
1105                         AV_DEBUG("Classword: %d \n", temp);
1106
1107                         assert(vr->classifications > 1 && vr->classifications<256 && temp<=65536); //needed for inverse[]
1108                         for(i=0;i<c_p_c;++i) {
1109                             uint_fast32_t temp2;
1110
1111                             temp2=(((uint_fast64_t)temp) * inverse[vr->classifications])>>32;
1112                             classifs[j_times_ptns_to_read+partition_count+c_p_c-1-i]=temp-temp2*vr->classifications;
1113                             temp=temp2;
1114                         }
1115                     }
1116                     j_times_ptns_to_read+=ptns_to_read;
1117                 }
1118             }
1119             for(i=0;(i<c_p_c) && (partition_count<ptns_to_read);++i) {
1120                 for(j_times_ptns_to_read=0, j=0;j<ch_used;++j) {
1121                     uint_fast16_t voffs;
1122
1123                     if (!do_not_decode[j]) {
1124                         uint_fast8_t vqclass=classifs[j_times_ptns_to_read+partition_count];
1125                         int_fast16_t vqbook=vr->books[vqclass][pass];
1126
1127                         if (vqbook>=0) {
1128                             uint_fast16_t coffs;
1129                             uint_fast16_t step=vr->partition_size/vc->codebooks[vqbook].dimensions;
1130                             vorbis_codebook codebook= vc->codebooks[vqbook];
1131
1132                             if (vr->type==0) {
1133
1134                                 voffs=voffset+j*vlen;
1135                                 for(k=0;k<step;++k) {
1136                                     coffs=get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * codebook.dimensions;
1137                                     for(l=0;l<codebook.dimensions;++l) {
1138                                         vec[voffs+k+l*step]+=codebook.codevectors[coffs+l];  // FPMATH
1139                                     }
1140                                 }
1141                             }
1142                             else if (vr->type==1) {
1143                                 voffs=voffset+j*vlen;
1144                                 for(k=0;k<step;++k) {
1145                                     coffs=get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * codebook.dimensions;
1146                                     for(l=0;l<codebook.dimensions;++l, ++voffs) {
1147                                         vec[voffs]+=codebook.codevectors[coffs+l];  // FPMATH
1148
1149                                         AV_DEBUG(" pass %d offs: %d curr: %f change: %f cv offs.: %d  \n", pass, voffs, vec[voffs], codebook.codevectors[coffs+l], coffs);
1150                                     }
1151                                 }
1152                             }
1153                             else if (vr->type==2 && ch==2 && (voffset&1)==0 && (codebook.dimensions&1)==0) { // most frequent case optimized
1154                                 voffs=voffset>>1;
1155
1156                                 for(k=0;k<step;++k) {
1157                                     coffs=get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * codebook.dimensions;
1158                                     for(l=0;l<codebook.dimensions;l+=2, voffs++) {
1159                                         vec[voffs     ]+=codebook.codevectors[coffs+l  ];  // FPMATH
1160                                         vec[voffs+vlen]+=codebook.codevectors[coffs+l+1];  // FPMATH
1161
1162                                         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);
1163                                     }
1164                                 }
1165
1166                             }
1167                             else if (vr->type==2) {
1168                                 voffs=voffset;
1169
1170                                 for(k=0;k<step;++k) {
1171                                     coffs=get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * codebook.dimensions;
1172                                     for(l=0;l<codebook.dimensions;++l, ++voffs) {
1173                                         vec[voffs/ch+(voffs%ch)*vlen]+=codebook.codevectors[coffs+l];  // FPMATH FIXME use if and counter instead of / and %
1174
1175                                         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);
1176                                     }
1177                                 }
1178                             } else {
1179                                 av_log(vc->avccontext, AV_LOG_ERROR, " Invalid residue type while residue decode?! \n");
1180                                 return 1;
1181                             }
1182                         }
1183                     }
1184                     j_times_ptns_to_read+=ptns_to_read;
1185                 }
1186                 ++partition_count;
1187                 voffset+=vr->partition_size;
1188             }
1189         }
1190     }
1191     return 0;
1192 }
1193
1194 // Decode the audio packet using the functions above
1195 #define BIAS 385
1196
1197 static int vorbis_parse_audio_packet(vorbis_context *vc) {
1198     GetBitContext *gb=&vc->gb;
1199
1200     uint_fast8_t previous_window=0,next_window=0;
1201     uint_fast8_t mode_number;
1202     uint_fast16_t blocksize;
1203     int_fast32_t i,j;
1204     uint_fast8_t no_residue[vc->audio_channels];
1205     uint_fast8_t do_not_decode[vc->audio_channels];
1206     vorbis_mapping *mapping;
1207     float *ch_res_ptr=vc->channel_residues;
1208     float *ch_floor_ptr=vc->channel_floors;
1209     uint_fast8_t res_chan[vc->audio_channels];
1210     uint_fast8_t res_num=0;
1211     int_fast16_t retlen=0;
1212     uint_fast16_t saved_start=0;
1213
1214     if (get_bits1(gb)) {
1215         av_log(vc->avccontext, AV_LOG_ERROR, "Not a Vorbis I audio packet.\n");
1216         return -1; // packet type not audio
1217     }
1218
1219     if (vc->mode_count==1) {
1220         mode_number=0;
1221     } else {
1222         mode_number=get_bits(gb, ilog(vc->mode_count-1));
1223     }
1224     mapping=&vc->mappings[vc->modes[mode_number].mapping];
1225
1226     AV_DEBUG(" Mode number: %d , mapping: %d , blocktype %d \n", mode_number, vc->modes[mode_number].mapping, vc->modes[mode_number].blockflag);
1227
1228     if (vc->modes[mode_number].blockflag) {
1229         previous_window=get_bits1(gb);
1230         next_window=get_bits1(gb);
1231     }
1232
1233     blocksize=vc->modes[mode_number].blockflag ? vc->blocksize_1 : vc->blocksize_0;
1234     memset(ch_res_ptr, 0, sizeof(float)*vc->audio_channels*blocksize/2); //FIXME can this be removed ?
1235     memset(ch_floor_ptr, 0, sizeof(float)*vc->audio_channels*blocksize/2); //FIXME can this be removed ?
1236
1237 // Decode floor(1)
1238
1239     for(i=0;i<vc->audio_channels;++i) {
1240         vorbis_floor *floor;
1241         if (mapping->submaps>1) {
1242             floor=&vc->floors[mapping->submap_floor[mapping->mux[i]]];
1243         } else {
1244             floor=&vc->floors[mapping->submap_floor[0]];
1245         }
1246
1247         no_residue[i]=vorbis_floor1_decode(vc, floor, ch_floor_ptr);
1248         ch_floor_ptr+=blocksize/2;
1249     }
1250
1251 // Nonzero vector propagate
1252
1253     for(i=mapping->coupling_steps-1;i>=0;--i) {
1254         if (!(no_residue[mapping->magnitude[i]] & no_residue[mapping->angle[i]])) {
1255             no_residue[mapping->magnitude[i]]=0;
1256             no_residue[mapping->angle[i]]=0;
1257         }
1258     }
1259
1260 // Decode residue
1261
1262     for(i=0;i<mapping->submaps;++i) {
1263         vorbis_residue *residue;
1264         uint_fast8_t ch=0;
1265
1266         for(j=0;j<vc->audio_channels;++j) {
1267             if ((mapping->submaps==1) || (i=mapping->mux[j])) {
1268                 res_chan[j]=res_num;
1269                 if (no_residue[j]) {
1270                     do_not_decode[ch]=1;
1271                 } else {
1272                     do_not_decode[ch]=0;
1273                 }
1274                 ++ch;
1275                 ++res_num;
1276             }
1277         }
1278         residue=&vc->residues[mapping->submap_residue[i]];
1279         vorbis_residue_decode(vc, residue, ch, do_not_decode, ch_res_ptr, blocksize/2);
1280
1281         ch_res_ptr+=ch*blocksize/2;
1282     }
1283
1284 // Inverse coupling
1285
1286     for(i=mapping->coupling_steps-1;i>=0;--i) { //warning: i has to be signed
1287         float *mag, *ang;
1288
1289         mag=vc->channel_residues+res_chan[mapping->magnitude[i]]*blocksize/2;
1290         ang=vc->channel_residues+res_chan[mapping->angle[i]]*blocksize/2;
1291         for(j=0;j<blocksize/2;++j) {
1292             float temp;
1293             if (mag[j]>0.0) {
1294                 if (ang[j]>0.0) {
1295                     ang[j]=mag[j]-ang[j];
1296                 } else {
1297                     temp=ang[j];
1298                     ang[j]=mag[j];
1299                     mag[j]+=temp;
1300                 }
1301             } else {
1302                 if (ang[j]>0.0) {
1303                     ang[j]+=mag[j];
1304                 } else {
1305                     temp=ang[j];
1306                     ang[j]=mag[j];
1307                     mag[j]-=temp;
1308                 }
1309             }
1310         }
1311     }
1312
1313 // Dotproduct
1314
1315     for(j=0, ch_floor_ptr=vc->channel_floors;j<vc->audio_channels;++j,ch_floor_ptr+=blocksize/2) {
1316         ch_res_ptr=vc->channel_residues+res_chan[j]*blocksize/2;
1317
1318         for(i=0;i<blocksize/2;++i) {
1319             ch_floor_ptr[i]*=ch_res_ptr[i]; //FPMATH
1320         }
1321     }
1322
1323 // MDCT, overlap/add, save data for next overlapping  FPMATH
1324
1325     for(j=0;j<vc->audio_channels;++j) {
1326         uint_fast8_t step=vc->audio_channels;
1327         uint_fast16_t k;
1328         float *saved=vc->saved+j*vc->blocksize_1/2;
1329         float *ret=vc->ret;
1330         const float *lwin=vc->lwin;
1331         const float *swin=vc->swin;
1332         float *buf=vc->buf;
1333         float *buf_tmp=vc->buf_tmp;
1334
1335         ch_floor_ptr=vc->channel_floors+j*blocksize/2;
1336
1337         saved_start=vc->saved_start;
1338
1339         ff_imdct_calc(vc->modes[mode_number].blockflag ? &vc->mdct1 : &vc->mdct0, buf, ch_floor_ptr, buf_tmp);
1340
1341         if (vc->modes[mode_number].blockflag) {
1342             // -- overlap/add
1343             if (previous_window) {
1344                 for(k=j, i=0;i<vc->blocksize_1/2;++i, k+=step) {
1345                     ret[k]=saved[i]+buf[i]*lwin[i]+BIAS;
1346                 }
1347                 retlen=vc->blocksize_1/2;
1348             } else {
1349                 buf += (vc->blocksize_1-vc->blocksize_0)/4;
1350                 for(k=j, i=0;i<vc->blocksize_0/2;++i, k+=step) {
1351                     ret[k]=saved[i]+buf[i]*swin[i]+BIAS;
1352                 }
1353                 buf += vc->blocksize_0/2;
1354                 for(i=0;i<(vc->blocksize_1-vc->blocksize_0)/4;++i, k+=step) {
1355                     ret[k]=buf[i]+BIAS;
1356                 }
1357                 buf=vc->buf;
1358                 retlen=vc->blocksize_0/2+(vc->blocksize_1-vc->blocksize_0)/4;
1359             }
1360             // -- save
1361             if (next_window) {
1362                 buf += vc->blocksize_1/2;
1363                 lwin += vc->blocksize_1/2-1;
1364                 for(i=0;i<vc->blocksize_1/2;++i) {
1365                     saved[i]=buf[i]*lwin[-i];
1366                 }
1367                 saved_start=0;
1368             } else {
1369                 saved_start=(vc->blocksize_1-vc->blocksize_0)/4;
1370                 buf += vc->blocksize_1/2;
1371                 for(i=0;i<saved_start;++i) {
1372                     saved[i]=buf[i];
1373                 }
1374                 swin += vc->blocksize_0/2-1;
1375                 for(i=0;i<vc->blocksize_0/2;++i) {
1376                     saved[saved_start+i]=buf[saved_start+i]*swin[-i];
1377                 }
1378             }
1379         } else {
1380             // --overlap/add
1381             for(k=j, i=0;i<saved_start;++i, k+=step) {
1382                 ret[k]=saved[i]+BIAS;
1383             }
1384             for(i=0;i<vc->blocksize_0/2;++i, k+=step) {
1385                 ret[k]=saved[saved_start+i]+buf[i]*swin[i]+BIAS;
1386             }
1387             retlen=saved_start+vc->blocksize_0/2;
1388             // -- save
1389             buf += vc->blocksize_0/2;
1390             swin += vc->blocksize_0/2-1;
1391             for(i=0;i<vc->blocksize_0/2;++i) {
1392                 saved[i]=buf[i]*swin[-i];
1393             }
1394             saved_start=0;
1395         }
1396     }
1397     vc->saved_start=saved_start;
1398
1399     return retlen*vc->audio_channels;
1400 }
1401
1402 // Return the decoded audio packet through the standard api
1403
1404 static int vorbis_decode_frame(AVCodecContext *avccontext,
1405                         void *data, int *data_size,
1406                         uint8_t *buf, int buf_size)
1407 {
1408     vorbis_context *vc = avccontext->priv_data ;
1409     GetBitContext *gb = &(vc->gb);
1410
1411     int_fast16_t i, len;
1412
1413     if(!buf_size){
1414         return 0;
1415     }
1416
1417     AV_DEBUG("packet length %d \n", buf_size);
1418
1419     init_get_bits(gb, buf, buf_size*8);
1420
1421     len=vorbis_parse_audio_packet(vc);
1422
1423     if (len<=0) {
1424         *data_size=0;
1425         return buf_size;
1426     }
1427
1428     if (!vc->first_frame) {
1429         vc->first_frame=1;
1430         *data_size=0;
1431         return buf_size ;
1432     }
1433
1434     AV_DEBUG("parsed %d bytes %d bits, returned %d samples (*ch*bits) \n", get_bits_count(gb)/8, get_bits_count(gb)%8, len);
1435
1436     for(i=0;i<len;++i) {
1437         int_fast32_t tmp= ((int32_t*)vc->ret)[i];
1438         if(tmp & 0xf0000){
1439 //            tmp= (0x43c0ffff - tmp)>>31; //ask gcc devs why this is slower
1440             if(tmp > 0x43c0ffff) tmp= 0xFFFF;
1441             else                 tmp= 0;
1442         }
1443         ((int16_t*)data)[i]=tmp - 0x8000;
1444     }
1445
1446     *data_size=len*2;
1447
1448     return buf_size ;
1449 }
1450
1451 // Close decoder
1452
1453 static int vorbis_decode_close(AVCodecContext *avccontext) {
1454     vorbis_context *vc = avccontext->priv_data;
1455
1456     vorbis_free(vc);
1457
1458     return 0 ;
1459 }
1460
1461 AVCodec vorbis_decoder = {
1462     "vorbis",
1463     CODEC_TYPE_AUDIO,
1464     CODEC_ID_VORBIS,
1465     sizeof(vorbis_context),
1466     vorbis_decode_init,
1467     NULL,
1468     vorbis_decode_close,
1469     vorbis_decode_frame,
1470 };
1471