make some more functions global so they can be shared with vorbis_enc.c
[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 //#define V_DEBUG
24 //#define AV_DEBUG(...) av_log(NULL, AV_LOG_INFO, __VA_ARGS__)
25
26 #include <math.h>
27
28 #define ALT_BITSTREAM_READER_LE
29 #include "avcodec.h"
30 #include "bitstream.h"
31 #include "dsputil.h"
32
33 #include "vorbis.h"
34
35 #define V_NB_BITS 8
36 #define V_NB_BITS2 11
37 #define V_MAX_VLCS (1<<16)
38
39 #ifndef V_DEBUG
40 #define AV_DEBUG(...)
41 #endif
42
43 #undef NDEBUG
44 #include <assert.h>
45
46 typedef struct {
47     uint_fast8_t dimensions;
48     uint_fast8_t lookup_type;
49     uint_fast8_t maxdepth;
50     VLC vlc;
51     float *codevectors;
52     unsigned int nb_bits;
53 } vorbis_codebook;
54
55 typedef union vorbis_floor_u vorbis_floor_data;
56 typedef struct vorbis_floor0_s vorbis_floor0;
57 typedef struct vorbis_floor1_s vorbis_floor1;
58 struct vorbis_context_s;
59 typedef
60 uint_fast8_t (* vorbis_floor_decode_func)
61              (struct vorbis_context_s *, vorbis_floor_data *, float *);
62 typedef struct {
63     uint_fast8_t floor_type;
64     vorbis_floor_decode_func decode;
65     union vorbis_floor_u
66     {
67         struct vorbis_floor0_s
68         {
69             uint_fast8_t order;
70             uint_fast16_t rate;
71             uint_fast16_t bark_map_size;
72             int_fast32_t * map[2];
73             uint_fast32_t map_size[2];
74             uint_fast8_t amplitude_bits;
75             uint_fast8_t amplitude_offset;
76             uint_fast8_t num_books;
77             uint_fast8_t * book_list;
78             float * lsp;
79         } t0;
80         struct vorbis_floor1_s
81         {
82             uint_fast8_t partitions;
83             uint_fast8_t maximum_class;
84             uint_fast8_t partition_class[32];
85             uint_fast8_t class_dimensions[16];
86             uint_fast8_t class_subclasses[16];
87             uint_fast8_t class_masterbook[16];
88             int_fast16_t subclass_books[16][8];
89             uint_fast8_t multiplier;
90             uint_fast16_t x_list_dim;
91             floor1_entry_t * list;
92         } t1;
93     } data;
94 } vorbis_floor;
95
96 typedef struct {
97     uint_fast16_t type;
98     uint_fast32_t begin;
99     uint_fast32_t end;
100     uint_fast32_t partition_size;
101     uint_fast8_t classifications;
102     uint_fast8_t classbook;
103     int_fast16_t books[64][8];
104     uint_fast8_t maxpass;
105 } vorbis_residue;
106
107 typedef struct {
108     uint_fast8_t submaps;
109     uint_fast16_t coupling_steps;
110     uint_fast8_t *magnitude;
111     uint_fast8_t *angle;
112     uint_fast8_t *mux;
113     uint_fast8_t submap_floor[16];
114     uint_fast8_t submap_residue[16];
115 } vorbis_mapping;
116
117 typedef struct {
118     uint_fast8_t blockflag;
119     uint_fast16_t windowtype;
120     uint_fast16_t transformtype;
121     uint_fast8_t mapping;
122 } vorbis_mode;
123
124 typedef struct vorbis_context_s {
125     AVCodecContext *avccontext;
126     GetBitContext gb;
127     DSPContext dsp;
128
129     MDCTContext mdct[2];
130     uint_fast8_t first_frame;
131     uint_fast32_t version;
132     uint_fast8_t audio_channels;
133     uint_fast32_t audio_samplerate;
134     uint_fast32_t bitrate_maximum;
135     uint_fast32_t bitrate_nominal;
136     uint_fast32_t bitrate_minimum;
137     uint_fast32_t blocksize[2];
138     const float * win[2];
139     uint_fast16_t codebook_count;
140     vorbis_codebook *codebooks;
141     uint_fast8_t floor_count;
142     vorbis_floor *floors;
143     uint_fast8_t residue_count;
144     vorbis_residue *residues;
145     uint_fast8_t mapping_count;
146     vorbis_mapping *mappings;
147     uint_fast8_t mode_count;
148     vorbis_mode *modes;
149     uint_fast8_t mode_number; // mode number for the current packet
150     float *channel_residues;
151     float *channel_floors;
152     float *saved;
153     uint_fast16_t saved_start;
154     float *ret;
155     float *buf;
156     float *buf_tmp;
157     uint_fast32_t add_bias; // for float->int conversion
158     uint_fast32_t exp_bias;
159 } vorbis_context;
160
161 /* Helper functions */
162
163 #define BARK(x) \
164     (13.1f*atan(0.00074f*(x))+2.24f*atan(1.85e-8f*(x)*(x))+1e-4f*(x))
165
166 unsigned int ff_vorbis_nth_root(unsigned int x, unsigned int n) {   // x^(1/n)
167     unsigned int ret=0, i, j;
168
169     do {
170         ++ret;
171         for(i=0,j=ret;i<n-1;i++) j*=ret;
172     } while (j<=x);
173
174     return (ret-1);
175 }
176
177 static float vorbisfloat2float(uint_fast32_t val) {
178     double mant=val&0x1fffff;
179     long exp=(val&0x7fe00000L)>>21;
180     if (val&0x80000000) mant=-mant;
181     return(ldexp(mant, exp-20-768));
182 }
183
184
185 // Generate vlc codes from vorbis huffman code lengths
186
187 int ff_vorbis_len2vlc(uint8_t *bits, uint32_t *codes, uint_fast32_t num) {
188     uint_fast32_t exit_at_level[33]={404,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
189         0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
190
191     uint_fast8_t i,j;
192     uint_fast32_t code,p;
193
194 #ifdef V_DEBUG
195     GetBitContext gb;
196 #endif
197
198     for(p=0;(bits[p]==0) && (p<num);++p);
199     if (p==num) {
200 //        av_log(vc->avccontext, AV_LOG_INFO, "An empty codebook. Heh?! \n");
201         return 0;
202     }
203
204     codes[p]=0;
205     for(i=0;i<bits[p];++i) {
206         exit_at_level[i+1]=1<<i;
207     }
208
209 #ifdef V_DEBUG
210     av_log(NULL, AV_LOG_INFO, " %d. of %d code len %d code %d - ", p, num, bits[p], codes[p]);
211     init_get_bits(&gb, (uint_fast8_t *)&codes[p], bits[p]);
212     for(i=0;i<bits[p];++i) {
213         av_log(NULL, AV_LOG_INFO, "%s", get_bits1(&gb) ? "1" : "0");
214     }
215     av_log(NULL, AV_LOG_INFO, "\n");
216 #endif
217
218     ++p;
219
220     for(;p<num;++p) {
221         if (bits[p]==0) continue;
222         // find corresponding exit(node which the tree can grow further from)
223         for(i=bits[p];i>0;--i) {
224             if (exit_at_level[i]) break;
225         }
226         if (!i) return 1; // overspecified tree
227         code=exit_at_level[i];
228         exit_at_level[i]=0;
229         // construct code (append 0s to end) and introduce new exits
230         for(j=i+1;j<=bits[p];++j) {
231             exit_at_level[j]=code+(1<<(j-1));
232         }
233         codes[p]=code;
234
235 #ifdef V_DEBUG
236         av_log(NULL, AV_LOG_INFO, " %d. code len %d code %d - ", p, bits[p], codes[p]);
237         init_get_bits(&gb, (uint_fast8_t *)&codes[p], bits[p]);
238         for(i=0;i<bits[p];++i) {
239             av_log(NULL, AV_LOG_INFO, "%s", get_bits1(&gb) ? "1" : "0");
240         }
241         av_log(NULL, AV_LOG_INFO, "\n");
242 #endif
243
244     }
245
246     //no exits should be left (underspecified tree - ie. unused valid vlcs - not allowed by SPEC)
247     for (p=1; p<33; p++)
248         if (exit_at_level[p]) return 1;
249
250     return 0;
251 }
252
253 void ff_vorbis_ready_floor1_list(floor1_entry_t * list, int values) {
254     int i;
255     list[0].sort = 0;
256     list[1].sort = 1;
257     for (i = 2; i < values; i++) {
258         int j;
259         list[i].low = 0;
260         list[i].high = 1;
261         list[i].sort = i;
262         for (j = 2; j < i; j++) {
263             int tmp = list[j].x;
264             if (tmp < list[i].x) {
265                 if (tmp > list[list[i].low].x) list[i].low = j;
266             } else {
267                 if (tmp < list[list[i].high].x) list[i].high = j;
268             }
269         }
270     }
271     for (i = 0; i < values - 1; i++) {
272         int j;
273         for (j = i + 1; j < values; j++) {
274             if (list[list[i].sort].x > list[list[j].sort].x) {
275                 int tmp = list[i].sort;
276                 list[i].sort = list[j].sort;
277                 list[j].sort = tmp;
278             }
279         }
280     }
281 }
282
283 // Free all allocated memory -----------------------------------------
284
285 static void vorbis_free(vorbis_context *vc) {
286     int_fast16_t i;
287
288     av_freep(&vc->channel_residues);
289     av_freep(&vc->channel_floors);
290     av_freep(&vc->saved);
291     av_freep(&vc->ret);
292     av_freep(&vc->buf);
293     av_freep(&vc->buf_tmp);
294
295     av_freep(&vc->residues);
296     av_freep(&vc->modes);
297
298     ff_mdct_end(&vc->mdct[0]);
299     ff_mdct_end(&vc->mdct[1]);
300
301     for(i=0;i<vc->codebook_count;++i) {
302         av_free(vc->codebooks[i].codevectors);
303         free_vlc(&vc->codebooks[i].vlc);
304     }
305     av_freep(&vc->codebooks);
306
307     for(i=0;i<vc->floor_count;++i) {
308         if(vc->floors[i].floor_type==0) {
309             av_free(vc->floors[i].data.t0.map[0]);
310             av_free(vc->floors[i].data.t0.map[1]);
311             av_free(vc->floors[i].data.t0.book_list);
312             av_free(vc->floors[i].data.t0.lsp);
313         }
314         else {
315             av_free(vc->floors[i].data.t1.list);
316         }
317     }
318     av_freep(&vc->floors);
319
320     for(i=0;i<vc->mapping_count;++i) {
321         av_free(vc->mappings[i].magnitude);
322         av_free(vc->mappings[i].angle);
323         av_free(vc->mappings[i].mux);
324     }
325     av_freep(&vc->mappings);
326
327     if(vc->exp_bias){
328         av_freep(&vc->win[0]);
329         av_freep(&vc->win[1]);
330     }
331 }
332
333 // Parse setup header -------------------------------------------------
334
335 // Process codebooks part
336
337 static int vorbis_parse_setup_hdr_codebooks(vorbis_context *vc) {
338     uint_fast16_t cb;
339     uint8_t *tmp_vlc_bits;
340     uint32_t *tmp_vlc_codes;
341     GetBitContext *gb=&vc->gb;
342
343     vc->codebook_count=get_bits(gb,8)+1;
344
345     AV_DEBUG(" Codebooks: %d \n", vc->codebook_count);
346
347     vc->codebooks=(vorbis_codebook *)av_mallocz(vc->codebook_count * sizeof(vorbis_codebook));
348     tmp_vlc_bits=(uint8_t *)av_mallocz(V_MAX_VLCS * sizeof(uint8_t));
349     tmp_vlc_codes=(uint32_t *)av_mallocz(V_MAX_VLCS * sizeof(uint32_t));
350
351     for(cb=0;cb<vc->codebook_count;++cb) {
352         vorbis_codebook *codebook_setup=&vc->codebooks[cb];
353         uint_fast8_t ordered;
354         uint_fast32_t t, used_entries=0;
355         uint_fast32_t entries;
356
357         AV_DEBUG(" %d. Codebook \n", cb);
358
359         if (get_bits(gb, 24)!=0x564342) {
360             av_log(vc->avccontext, AV_LOG_ERROR, " %"PRIdFAST16". Codebook setup data corrupt. \n", cb);
361             goto error;
362         }
363
364         codebook_setup->dimensions=get_bits(gb, 16);
365         if (codebook_setup->dimensions>16) {
366             av_log(vc->avccontext, AV_LOG_ERROR, " %"PRIdFAST16". Codebook's dimension is too large (%d). \n", cb, codebook_setup->dimensions);
367             goto error;
368         }
369         entries=get_bits(gb, 24);
370         if (entries>V_MAX_VLCS) {
371             av_log(vc->avccontext, AV_LOG_ERROR, " %"PRIdFAST16". Codebook has too many entries (%"PRIdFAST32"). \n", cb, entries);
372             goto error;
373         }
374
375         ordered=get_bits1(gb);
376
377         AV_DEBUG(" codebook_dimensions %d, codebook_entries %d \n", codebook_setup->dimensions, entries);
378
379         if (!ordered) {
380             uint_fast16_t ce;
381             uint_fast8_t flag;
382             uint_fast8_t sparse=get_bits1(gb);
383
384             AV_DEBUG(" not ordered \n");
385
386             if (sparse) {
387                 AV_DEBUG(" sparse \n");
388
389                 used_entries=0;
390                 for(ce=0;ce<entries;++ce) {
391                     flag=get_bits1(gb);
392                     if (flag) {
393                         tmp_vlc_bits[ce]=get_bits(gb, 5)+1;
394                         ++used_entries;
395                     }
396                     else tmp_vlc_bits[ce]=0;
397                 }
398             } else {
399                 AV_DEBUG(" not sparse \n");
400
401                 used_entries=entries;
402                 for(ce=0;ce<entries;++ce) {
403                     tmp_vlc_bits[ce]=get_bits(gb, 5)+1;
404                 }
405             }
406         } else {
407             uint_fast16_t current_entry=0;
408             uint_fast8_t current_length=get_bits(gb, 5)+1;
409
410             AV_DEBUG(" ordered, current length: %d \n", current_length);  //FIXME
411
412             used_entries=entries;
413             for(;current_entry<used_entries;++current_length) {
414                 uint_fast16_t i, number;
415
416                 AV_DEBUG(" number bits: %d ", ilog(entries - current_entry));
417
418                 number=get_bits(gb, ilog(entries - current_entry));
419
420                 AV_DEBUG(" number: %d \n", number);
421
422                 for(i=current_entry;i<number+current_entry;++i) {
423                     if (i<used_entries) tmp_vlc_bits[i]=current_length;
424                 }
425
426                 current_entry+=number;
427             }
428             if (current_entry>used_entries) {
429                 av_log(vc->avccontext, AV_LOG_ERROR, " More codelengths than codes in codebook. \n");
430                 goto error;
431             }
432         }
433
434         codebook_setup->lookup_type=get_bits(gb, 4);
435
436         AV_DEBUG(" lookup type: %d : %s \n", codebook_setup->lookup_type, codebook_setup->lookup_type ? "vq" : "no lookup" );
437
438 // If the codebook is used for (inverse) VQ, calculate codevectors.
439
440         if (codebook_setup->lookup_type==1) {
441             uint_fast16_t i, j, k;
442             uint_fast16_t codebook_lookup_values=ff_vorbis_nth_root(entries, codebook_setup->dimensions);
443             uint_fast16_t codebook_multiplicands[codebook_lookup_values];
444
445             float codebook_minimum_value=vorbisfloat2float(get_bits_long(gb, 32));
446             float codebook_delta_value=vorbisfloat2float(get_bits_long(gb, 32));
447             uint_fast8_t codebook_value_bits=get_bits(gb, 4)+1;
448             uint_fast8_t codebook_sequence_p=get_bits1(gb);
449
450             AV_DEBUG(" We expect %d numbers for building the codevectors. \n", codebook_lookup_values);
451             AV_DEBUG("  delta %f minmum %f \n", codebook_delta_value, codebook_minimum_value);
452
453             for(i=0;i<codebook_lookup_values;++i) {
454                 codebook_multiplicands[i]=get_bits(gb, codebook_value_bits);
455
456                 AV_DEBUG(" multiplicands*delta+minmum : %e \n", (float)codebook_multiplicands[i]*codebook_delta_value+codebook_minimum_value);
457                 AV_DEBUG(" multiplicand %d \n", codebook_multiplicands[i]);
458             }
459
460 // Weed out unused vlcs and build codevector vector
461             codebook_setup->codevectors=(float *)av_mallocz(used_entries*codebook_setup->dimensions * sizeof(float));
462             for(j=0, i=0;i<entries;++i) {
463                 uint_fast8_t dim=codebook_setup->dimensions;
464
465                 if (tmp_vlc_bits[i]) {
466                     float last=0.0;
467                     uint_fast32_t lookup_offset=i;
468
469 #ifdef V_DEBUG
470                     av_log(vc->avccontext, AV_LOG_INFO, "Lookup offset %d ,", i);
471 #endif
472
473                     for(k=0;k<dim;++k) {
474                         uint_fast32_t multiplicand_offset = lookup_offset % codebook_lookup_values;
475                         codebook_setup->codevectors[j*dim+k]=codebook_multiplicands[multiplicand_offset]*codebook_delta_value+codebook_minimum_value+last;
476                         if (codebook_sequence_p) {
477                             last=codebook_setup->codevectors[j*dim+k];
478                         }
479                         lookup_offset/=codebook_lookup_values;
480                     }
481                     tmp_vlc_bits[j]=tmp_vlc_bits[i];
482
483 #ifdef V_DEBUG
484                     av_log(vc->avccontext, AV_LOG_INFO, "real lookup offset %d, vector: ", j);
485                     for(k=0;k<dim;++k) {
486                         av_log(vc->avccontext, AV_LOG_INFO, " %f ", codebook_setup->codevectors[j*dim+k]);
487                     }
488                     av_log(vc->avccontext, AV_LOG_INFO, "\n");
489 #endif
490
491                     ++j;
492                 }
493             }
494             if (j!=used_entries) {
495                 av_log(vc->avccontext, AV_LOG_ERROR, "Bug in codevector vector building code. \n");
496                 goto error;
497             }
498             entries=used_entries;
499         }
500         else if (codebook_setup->lookup_type>=2) {
501             av_log(vc->avccontext, AV_LOG_ERROR, "Codebook lookup type not supported. \n");
502             goto error;
503         }
504
505 // Initialize VLC table
506         if (ff_vorbis_len2vlc(tmp_vlc_bits, tmp_vlc_codes, entries)) {
507             av_log(vc->avccontext, AV_LOG_ERROR, " Invalid code lengths while generating vlcs. \n");
508             goto error;
509         }
510         codebook_setup->maxdepth=0;
511         for(t=0;t<entries;++t)
512             if (tmp_vlc_bits[t]>=codebook_setup->maxdepth) codebook_setup->maxdepth=tmp_vlc_bits[t];
513
514         if(codebook_setup->maxdepth > 3*V_NB_BITS) codebook_setup->nb_bits=V_NB_BITS2;
515         else                                       codebook_setup->nb_bits=V_NB_BITS;
516
517         codebook_setup->maxdepth=(codebook_setup->maxdepth+codebook_setup->nb_bits-1)/codebook_setup->nb_bits;
518
519         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)) {
520             av_log(vc->avccontext, AV_LOG_ERROR, " Error generating vlc tables. \n");
521             goto error;
522         }
523     }
524
525     av_free(tmp_vlc_bits);
526     av_free(tmp_vlc_codes);
527     return 0;
528
529 // Error:
530 error:
531     av_free(tmp_vlc_bits);
532     av_free(tmp_vlc_codes);
533     return 1;
534 }
535
536 // Process time domain transforms part (unused in Vorbis I)
537
538 static int vorbis_parse_setup_hdr_tdtransforms(vorbis_context *vc) {
539     GetBitContext *gb=&vc->gb;
540     uint_fast8_t i;
541     uint_fast8_t vorbis_time_count=get_bits(gb, 6)+1;
542
543     for(i=0;i<vorbis_time_count;++i) {
544         uint_fast16_t vorbis_tdtransform=get_bits(gb, 16);
545
546         AV_DEBUG(" Vorbis time domain transform %d: %d \n", vorbis_time_count, vorbis_tdtransform);
547
548         if (vorbis_tdtransform) {
549             av_log(vc->avccontext, AV_LOG_ERROR, "Vorbis time domain transform data nonzero. \n");
550             return 1;
551         }
552     }
553     return 0;
554 }
555
556 // Process floors part
557
558 static uint_fast8_t vorbis_floor0_decode(vorbis_context *vc,
559                                          vorbis_floor_data *vfu, float *vec);
560 static void create_map( vorbis_context * vc, uint_fast8_t floor_number );
561 static uint_fast8_t vorbis_floor1_decode(vorbis_context *vc,
562                                          vorbis_floor_data *vfu, float *vec);
563 static int vorbis_parse_setup_hdr_floors(vorbis_context *vc) {
564     GetBitContext *gb=&vc->gb;
565     uint_fast16_t i,j,k;
566
567     vc->floor_count=get_bits(gb, 6)+1;
568
569     vc->floors=(vorbis_floor *)av_mallocz(vc->floor_count * sizeof(vorbis_floor));
570
571     for (i=0;i<vc->floor_count;++i) {
572         vorbis_floor *floor_setup=&vc->floors[i];
573
574         floor_setup->floor_type=get_bits(gb, 16);
575
576         AV_DEBUG(" %d. floor type %d \n", i, floor_setup->floor_type);
577
578         if (floor_setup->floor_type==1) {
579             uint_fast8_t maximum_class=0;
580             uint_fast8_t rangebits;
581             uint_fast16_t floor1_values=2;
582
583             floor_setup->decode=vorbis_floor1_decode;
584
585             floor_setup->data.t1.partitions=get_bits(gb, 5);
586
587             AV_DEBUG(" %d.floor: %d partitions \n", i, floor_setup->data.t1.partitions);
588
589             for(j=0;j<floor_setup->data.t1.partitions;++j) {
590                 floor_setup->data.t1.partition_class[j]=get_bits(gb, 4);
591                 if (floor_setup->data.t1.partition_class[j]>maximum_class) maximum_class=floor_setup->data.t1.partition_class[j];
592
593                 AV_DEBUG(" %d. floor %d partition class %d \n", i, j, floor_setup->data.t1.partition_class[j]);
594
595             }
596
597             AV_DEBUG(" maximum class %d \n", maximum_class);
598
599             floor_setup->data.t1.maximum_class=maximum_class;
600
601             for(j=0;j<=maximum_class;++j) {
602                 floor_setup->data.t1.class_dimensions[j]=get_bits(gb, 3)+1;
603                 floor_setup->data.t1.class_subclasses[j]=get_bits(gb, 2);
604
605                 AV_DEBUG(" %d floor %d class dim: %d subclasses %d \n", i, j, floor_setup->data.t1.class_dimensions[j], floor_setup->data.t1.class_subclasses[j]);
606
607                 if (floor_setup->data.t1.class_subclasses[j]) {
608                     floor_setup->data.t1.class_masterbook[j]=get_bits(gb, 8);
609
610                     AV_DEBUG("   masterbook: %d \n", floor_setup->data.t1.class_masterbook[j]);
611                 }
612
613                 for(k=0;k<(1<<floor_setup->data.t1.class_subclasses[j]);++k) {
614                     floor_setup->data.t1.subclass_books[j][k]=(int16_t)get_bits(gb, 8)-1;
615
616                     AV_DEBUG("    book %d. : %d \n", k, floor_setup->data.t1.subclass_books[j][k]);
617                 }
618             }
619
620             floor_setup->data.t1.multiplier=get_bits(gb, 2)+1;
621             floor_setup->data.t1.x_list_dim=2;
622
623             for(j=0;j<floor_setup->data.t1.partitions;++j) {
624                 floor_setup->data.t1.x_list_dim+=floor_setup->data.t1.class_dimensions[floor_setup->data.t1.partition_class[j]];
625             }
626
627             floor_setup->data.t1.list=(floor1_entry_t *)av_mallocz(floor_setup->data.t1.x_list_dim * sizeof(floor1_entry_t));
628
629
630             rangebits=get_bits(gb, 4);
631             floor_setup->data.t1.list[0].x = 0;
632             floor_setup->data.t1.list[1].x = (1<<rangebits);
633
634             for(j=0;j<floor_setup->data.t1.partitions;++j) {
635                 for(k=0;k<floor_setup->data.t1.class_dimensions[floor_setup->data.t1.partition_class[j]];++k,++floor1_values) {
636                     floor_setup->data.t1.list[floor1_values].x=get_bits(gb, rangebits);
637
638                     AV_DEBUG(" %d. floor1 Y coord. %d \n", floor1_values, floor_setup->data.t1.list[floor1_values].x);
639                 }
640             }
641
642 // Precalculate order of x coordinates - needed for decode
643             ff_vorbis_ready_floor1_list(floor_setup->data.t1.list, floor_setup->data.t1.x_list_dim);
644         }
645         else if(floor_setup->floor_type==0) {
646             uint_fast8_t max_codebook_dim=0;
647
648             floor_setup->decode=vorbis_floor0_decode;
649
650             floor_setup->data.t0.order=get_bits(gb, 8);
651             floor_setup->data.t0.rate=get_bits(gb, 16);
652             floor_setup->data.t0.bark_map_size=get_bits(gb, 16);
653             floor_setup->data.t0.amplitude_bits=get_bits(gb, 6);
654             /* zero would result in a div by zero later *
655              * 2^0 - 1 == 0                             */
656             if (floor_setup->data.t0.amplitude_bits == 0) {
657               av_log(vc->avccontext, AV_LOG_ERROR,
658                      "Floor 0 amplitude bits is 0.\n");
659               return 1;
660             }
661             floor_setup->data.t0.amplitude_offset=get_bits(gb, 8);
662             floor_setup->data.t0.num_books=get_bits(gb, 4)+1;
663
664             /* allocate mem for booklist */
665             floor_setup->data.t0.book_list=
666                 av_malloc(floor_setup->data.t0.num_books);
667             if(!floor_setup->data.t0.book_list) { return 1; }
668             /* read book indexes */
669             {
670                 int idx;
671                 uint_fast8_t book_idx;
672                 for (idx=0;idx<floor_setup->data.t0.num_books;++idx) {
673                     book_idx=get_bits(gb, 8);
674                     floor_setup->data.t0.book_list[idx]=book_idx;
675                     if (vc->codebooks[book_idx].dimensions > max_codebook_dim)
676                         max_codebook_dim=vc->codebooks[book_idx].dimensions;
677
678                     if (floor_setup->data.t0.book_list[idx]>vc->codebook_count)
679                         return 1;
680                 }
681             }
682
683             create_map( vc, i );
684
685             /* allocate mem for lsp coefficients */
686             {
687                 /* codebook dim is for padding if codebook dim doesn't *
688                  * divide order+1 then we need to read more data       */
689                 floor_setup->data.t0.lsp=
690                     av_malloc((floor_setup->data.t0.order+1 + max_codebook_dim)
691                               * sizeof(float));
692                 if(!floor_setup->data.t0.lsp) { return 1; }
693             }
694
695 #ifdef V_DEBUG /* debug output parsed headers */
696             AV_DEBUG("floor0 order: %u\n", floor_setup->data.t0.order);
697             AV_DEBUG("floor0 rate: %u\n", floor_setup->data.t0.rate);
698             AV_DEBUG("floor0 bark map size: %u\n",
699               floor_setup->data.t0.bark_map_size);
700             AV_DEBUG("floor0 amplitude bits: %u\n",
701               floor_setup->data.t0.amplitude_bits);
702             AV_DEBUG("floor0 amplitude offset: %u\n",
703               floor_setup->data.t0.amplitude_offset);
704             AV_DEBUG("floor0 number of books: %u\n",
705               floor_setup->data.t0.num_books);
706             AV_DEBUG("floor0 book list pointer: %p\n",
707               floor_setup->data.t0.book_list);
708             {
709               int idx;
710               for (idx=0;idx<floor_setup->data.t0.num_books;++idx) {
711                 AV_DEBUG( "  Book %d: %u\n",
712                   idx+1,
713                   floor_setup->data.t0.book_list[idx] );
714               }
715             }
716 #endif
717         }
718         else {
719             av_log(vc->avccontext, AV_LOG_ERROR, "Invalid floor type!\n");
720             return 1;
721         }
722     }
723     return 0;
724 }
725
726 // Process residues part
727
728 static int vorbis_parse_setup_hdr_residues(vorbis_context *vc){
729     GetBitContext *gb=&vc->gb;
730     uint_fast8_t i, j, k;
731
732     vc->residue_count=get_bits(gb, 6)+1;
733     vc->residues=(vorbis_residue *)av_mallocz(vc->residue_count * sizeof(vorbis_residue));
734
735     AV_DEBUG(" There are %d residues. \n", vc->residue_count);
736
737     for(i=0;i<vc->residue_count;++i) {
738         vorbis_residue *res_setup=&vc->residues[i];
739         uint_fast8_t cascade[64];
740         uint_fast8_t high_bits;
741         uint_fast8_t low_bits;
742
743         res_setup->type=get_bits(gb, 16);
744
745         AV_DEBUG(" %d. residue type %d \n", i, res_setup->type);
746
747         res_setup->begin=get_bits(gb, 24);
748         res_setup->end=get_bits(gb, 24);
749         res_setup->partition_size=get_bits(gb, 24)+1;
750         res_setup->classifications=get_bits(gb, 6)+1;
751         res_setup->classbook=get_bits(gb, 8);
752
753         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,
754           res_setup->classifications, res_setup->classbook);
755
756         for(j=0;j<res_setup->classifications;++j) {
757             high_bits=0;
758             low_bits=get_bits(gb, 3);
759             if (get_bits1(gb)) {
760                 high_bits=get_bits(gb, 5);
761             }
762             cascade[j]=(high_bits<<3)+low_bits;
763
764             AV_DEBUG("     %d class casscade depth: %d \n", j, ilog(cascade[j]));
765         }
766
767         res_setup->maxpass=0;
768         for(j=0;j<res_setup->classifications;++j) {
769             for(k=0;k<8;++k) {
770                 if (cascade[j]&(1<<k)) {
771                         res_setup->books[j][k]=get_bits(gb, 8);
772
773                     AV_DEBUG("     %d class casscade depth %d book: %d \n", j, k, res_setup->books[j][k]);
774
775                     if (k>res_setup->maxpass) {
776                         res_setup->maxpass=k;
777                     }
778                 } else {
779                     res_setup->books[j][k]=-1;
780                 }
781             }
782         }
783     }
784     return 0;
785 }
786
787 // Process mappings part
788
789 static int vorbis_parse_setup_hdr_mappings(vorbis_context *vc) {
790     GetBitContext *gb=&vc->gb;
791     uint_fast8_t i, j;
792
793     vc->mapping_count=get_bits(gb, 6)+1;
794     vc->mappings=(vorbis_mapping *)av_mallocz(vc->mapping_count * sizeof(vorbis_mapping));
795
796     AV_DEBUG(" There are %d mappings. \n", vc->mapping_count);
797
798     for(i=0;i<vc->mapping_count;++i) {
799         vorbis_mapping *mapping_setup=&vc->mappings[i];
800
801         if (get_bits(gb, 16)) {
802             av_log(vc->avccontext, AV_LOG_ERROR, "Other mappings than type 0 are not compliant with the Vorbis I specification. \n");
803             return 1;
804         }
805         if (get_bits1(gb)) {
806             mapping_setup->submaps=get_bits(gb, 4)+1;
807         } else {
808             mapping_setup->submaps=1;
809         }
810
811         if (get_bits1(gb)) {
812             mapping_setup->coupling_steps=get_bits(gb, 8)+1;
813             mapping_setup->magnitude=(uint_fast8_t *)av_mallocz(mapping_setup->coupling_steps * sizeof(uint_fast8_t));
814             mapping_setup->angle=(uint_fast8_t *)av_mallocz(mapping_setup->coupling_steps * sizeof(uint_fast8_t));
815             for(j=0;j<mapping_setup->coupling_steps;++j) {
816                 mapping_setup->magnitude[j]=get_bits(gb, ilog(vc->audio_channels-1));
817                 mapping_setup->angle[j]=get_bits(gb, ilog(vc->audio_channels-1));
818                 // FIXME: sanity checks
819             }
820         } else {
821             mapping_setup->coupling_steps=0;
822         }
823
824         AV_DEBUG("   %d mapping coupling steps: %d \n", i, mapping_setup->coupling_steps);
825
826         if(get_bits(gb, 2)) {
827             av_log(vc->avccontext, AV_LOG_ERROR, "%d. mapping setup data invalid. \n", i);
828             return 1; // following spec.
829         }
830
831         if (mapping_setup->submaps>1) {
832             mapping_setup->mux=(uint_fast8_t *)av_mallocz(vc->audio_channels * sizeof(uint_fast8_t));
833             for(j=0;j<vc->audio_channels;++j) {
834                 mapping_setup->mux[j]=get_bits(gb, 4);
835             }
836         }
837
838         for(j=0;j<mapping_setup->submaps;++j) {
839             get_bits(gb, 8); // FIXME check?
840             mapping_setup->submap_floor[j]=get_bits(gb, 8);
841             mapping_setup->submap_residue[j]=get_bits(gb, 8);
842
843             AV_DEBUG("   %d mapping %d submap : floor %d, residue %d \n", i, j, mapping_setup->submap_floor[j], mapping_setup->submap_residue[j]);
844         }
845     }
846     return 0;
847 }
848
849 // Process modes part
850
851 static void create_map( vorbis_context * vc, uint_fast8_t floor_number )
852 {
853     vorbis_floor * floors=vc->floors;
854     vorbis_floor0 * vf;
855     int idx;
856     int_fast8_t blockflag;
857     int_fast32_t * map;
858     int_fast32_t n; //TODO: could theoretically be smaller?
859
860     for (blockflag=0;blockflag<2;++blockflag)
861     {
862     n=vc->blocksize[blockflag]/2;
863     floors[floor_number].data.t0.map[blockflag]=
864         av_malloc((n+1) * sizeof(int_fast32_t)); // n+sentinel
865
866     map=floors[floor_number].data.t0.map[blockflag];
867     vf=&floors[floor_number].data.t0;
868
869     for (idx=0; idx<n;++idx) {
870         map[idx]=floor( BARK((vf->rate*idx)/(2.0f*n)) *
871                               ((vf->bark_map_size)/
872                                BARK(vf->rate/2.0f )) );
873         if (vf->bark_map_size-1 < map[idx]) {
874             map[idx]=vf->bark_map_size-1;
875         }
876     }
877     map[n]=-1;
878     vf->map_size[blockflag]=n;
879     }
880
881 #   ifdef V_DEBUG
882     for(idx=0;idx<=n;++idx) {
883         AV_DEBUG("floor0 map: map at pos %d is %d\n",
884                  idx, map[idx]);
885     }
886 #   endif
887 }
888
889 static int vorbis_parse_setup_hdr_modes(vorbis_context *vc) {
890     GetBitContext *gb=&vc->gb;
891     uint_fast8_t i;
892
893     vc->mode_count=get_bits(gb, 6)+1;
894     vc->modes=(vorbis_mode *)av_mallocz(vc->mode_count * sizeof(vorbis_mode));
895
896     AV_DEBUG(" There are %d modes.\n", vc->mode_count);
897
898     for(i=0;i<vc->mode_count;++i) {
899         vorbis_mode *mode_setup=&vc->modes[i];
900
901         mode_setup->blockflag=get_bits(gb, 1);
902         mode_setup->windowtype=get_bits(gb, 16); //FIXME check
903         mode_setup->transformtype=get_bits(gb, 16); //FIXME check
904         mode_setup->mapping=get_bits(gb, 8); //FIXME check
905
906         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);
907     }
908     return 0;
909 }
910
911 // Process the whole setup header using the functions above
912
913 static int vorbis_parse_setup_hdr(vorbis_context *vc) {
914     GetBitContext *gb=&vc->gb;
915
916     if ((get_bits(gb, 8)!='v') || (get_bits(gb, 8)!='o') ||
917     (get_bits(gb, 8)!='r') || (get_bits(gb, 8)!='b') ||
918     (get_bits(gb, 8)!='i') || (get_bits(gb, 8)!='s')) {
919         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (no vorbis signature). \n");
920         return 1;
921     }
922
923     if (vorbis_parse_setup_hdr_codebooks(vc)) {
924         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (codebooks). \n");
925         return 2;
926     }
927     if (vorbis_parse_setup_hdr_tdtransforms(vc)) {
928         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (time domain transforms). \n");
929         return 3;
930     }
931     if (vorbis_parse_setup_hdr_floors(vc)) {
932         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (floors). \n");
933         return 4;
934     }
935     if (vorbis_parse_setup_hdr_residues(vc)) {
936         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (residues). \n");
937         return 5;
938     }
939     if (vorbis_parse_setup_hdr_mappings(vc)) {
940         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (mappings). \n");
941         return 6;
942     }
943     if (vorbis_parse_setup_hdr_modes(vc)) {
944         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (modes). \n");
945         return 7;
946     }
947     if (!get_bits1(gb)) {
948         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (framing flag). \n");
949         return 8; // framing flag bit unset error
950     }
951
952     return 0;
953 }
954
955 // Process the identification header
956
957 static int vorbis_parse_id_hdr(vorbis_context *vc){
958     GetBitContext *gb=&vc->gb;
959     uint_fast8_t bl0, bl1;
960
961     if ((get_bits(gb, 8)!='v') || (get_bits(gb, 8)!='o') ||
962     (get_bits(gb, 8)!='r') || (get_bits(gb, 8)!='b') ||
963     (get_bits(gb, 8)!='i') || (get_bits(gb, 8)!='s')) {
964         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis id header packet corrupt (no vorbis signature). \n");
965         return 1;
966     }
967
968     vc->version=get_bits_long(gb, 32);    //FIXME check 0
969     vc->audio_channels=get_bits(gb, 8);   //FIXME check >0
970     vc->audio_samplerate=get_bits_long(gb, 32);   //FIXME check >0
971     vc->bitrate_maximum=get_bits_long(gb, 32);
972     vc->bitrate_nominal=get_bits_long(gb, 32);
973     vc->bitrate_minimum=get_bits_long(gb, 32);
974     bl0=get_bits(gb, 4);
975     bl1=get_bits(gb, 4);
976     vc->blocksize[0]=(1<<bl0);
977     vc->blocksize[1]=(1<<bl1);
978     if (bl0>13 || bl0<6 || bl1>13 || bl1<6 || bl1<bl0) {
979         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis id header packet corrupt (illegal blocksize). \n");
980         return 3;
981     }
982     // output format int16
983     if (vc->blocksize[1]/2 * vc->audio_channels * 2 >
984                                              AVCODEC_MAX_AUDIO_FRAME_SIZE) {
985         av_log(vc->avccontext, AV_LOG_ERROR, "Vorbis channel count makes "
986                "output packets too large.\n");
987         return 4;
988     }
989     vc->win[0]=ff_vorbis_vwin[bl0-6];
990     vc->win[1]=ff_vorbis_vwin[bl1-6];
991
992     if(vc->exp_bias){
993         int i, j;
994         for(j=0; j<2; j++){
995             float *win = av_malloc(vc->blocksize[j]/2 * sizeof(float));
996             for(i=0; i<vc->blocksize[j]/2; i++)
997                 win[i] = vc->win[j][i] * (1<<15);
998             vc->win[j] = win;
999         }
1000     }
1001
1002     if ((get_bits1(gb)) == 0) {
1003         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis id header packet corrupt (framing flag not set). \n");
1004         return 2;
1005     }
1006
1007     vc->channel_residues=(float *)av_malloc((vc->blocksize[1]/2)*vc->audio_channels * sizeof(float));
1008     vc->channel_floors=(float *)av_malloc((vc->blocksize[1]/2)*vc->audio_channels * sizeof(float));
1009     vc->saved=(float *)av_malloc((vc->blocksize[1]/2)*vc->audio_channels * sizeof(float));
1010     vc->ret=(float *)av_malloc((vc->blocksize[1]/2)*vc->audio_channels * sizeof(float));
1011     vc->buf=(float *)av_malloc(vc->blocksize[1] * sizeof(float));
1012     vc->buf_tmp=(float *)av_malloc(vc->blocksize[1] * sizeof(float));
1013     vc->saved_start=0;
1014
1015     ff_mdct_init(&vc->mdct[0], bl0, 1);
1016     ff_mdct_init(&vc->mdct[1], bl1, 1);
1017
1018     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 ",
1019             vc->version, vc->audio_channels, vc->audio_samplerate, vc->bitrate_maximum, vc->bitrate_nominal, vc->bitrate_minimum, vc->blocksize[0], vc->blocksize[1]);
1020
1021 /*
1022     BLK=vc->blocksize[0];
1023     for(i=0;i<BLK/2;++i) {
1024         vc->win[0][i]=sin(0.5*3.14159265358*(sin(((float)i+0.5)/(float)BLK*3.14159265358))*(sin(((float)i+0.5)/(float)BLK*3.14159265358)));
1025     }
1026 */
1027
1028     return 0;
1029 }
1030
1031 // Process the extradata using the functions above (identification header, setup header)
1032
1033 static int vorbis_decode_init(AVCodecContext *avccontext) {
1034     vorbis_context *vc = avccontext->priv_data ;
1035     uint8_t *headers = avccontext->extradata;
1036     int headers_len=avccontext->extradata_size;
1037     uint8_t *header_start[3];
1038     int header_len[3];
1039     GetBitContext *gb = &(vc->gb);
1040     int i, j, hdr_type;
1041
1042     vc->avccontext = avccontext;
1043     dsputil_init(&vc->dsp, avccontext);
1044
1045     if(vc->dsp.float_to_int16 == ff_float_to_int16_c) {
1046         vc->add_bias = 385;
1047         vc->exp_bias = 0;
1048     } else {
1049         vc->add_bias = 0;
1050         vc->exp_bias = 15<<23;
1051     }
1052
1053     if (!headers_len) {
1054         av_log(avccontext, AV_LOG_ERROR, "Extradata corrupt.\n");
1055         return -1;
1056     }
1057
1058     if(headers[0] == 0 && headers[1] == 30) {
1059         for(i = 0; i < 3; i++){
1060             header_len[i] = *headers++ << 8;
1061             header_len[i] += *headers++;
1062             header_start[i] = headers;
1063             headers += header_len[i];
1064         }
1065     } else if(headers[0] == 2) {
1066         for(j=1,i=0;i<2;++i, ++j) {
1067             header_len[i]=0;
1068             while(j<headers_len && headers[j]==0xff) {
1069                 header_len[i]+=0xff;
1070                 ++j;
1071             }
1072             if (j>=headers_len) {
1073                 av_log(avccontext, AV_LOG_ERROR, "Extradata corrupt.\n");
1074                 return -1;
1075             }
1076             header_len[i]+=headers[j];
1077         }
1078         header_len[2]=headers_len-header_len[0]-header_len[1]-j;
1079         headers+=j;
1080         header_start[0] = headers;
1081         header_start[1] = header_start[0] + header_len[0];
1082         header_start[2] = header_start[1] + header_len[1];
1083     } else {
1084         av_log(avccontext, AV_LOG_ERROR, "Extradata corrupt.\n");
1085         return -1;
1086     }
1087
1088     init_get_bits(gb, header_start[0], header_len[0]*8);
1089     hdr_type=get_bits(gb, 8);
1090     if (hdr_type!=1) {
1091         av_log(avccontext, AV_LOG_ERROR, "First header is not the id header.\n");
1092         return -1;
1093     }
1094     if (vorbis_parse_id_hdr(vc)) {
1095         av_log(avccontext, AV_LOG_ERROR, "Id header corrupt.\n");
1096         vorbis_free(vc);
1097         return -1;
1098     }
1099
1100     init_get_bits(gb, header_start[2], header_len[2]*8);
1101     hdr_type=get_bits(gb, 8);
1102     if (hdr_type!=5) {
1103         av_log(avccontext, AV_LOG_ERROR, "Third header is not the setup header.\n");
1104         return -1;
1105     }
1106     if (vorbis_parse_setup_hdr(vc)) {
1107         av_log(avccontext, AV_LOG_ERROR, "Setup header corrupt.\n");
1108         vorbis_free(vc);
1109         return -1;
1110     }
1111
1112     avccontext->channels = vc->audio_channels;
1113     avccontext->sample_rate = vc->audio_samplerate;
1114
1115     return 0 ;
1116 }
1117
1118 // Decode audiopackets -------------------------------------------------
1119
1120 // Read and decode floor
1121
1122 static uint_fast8_t vorbis_floor0_decode(vorbis_context *vc,
1123                                          vorbis_floor_data *vfu, float *vec) {
1124     vorbis_floor0 * vf=&vfu->t0;
1125     float * lsp=vf->lsp;
1126     uint_fast32_t amplitude;
1127     uint_fast32_t book_idx;
1128     uint_fast8_t blockflag=vc->modes[vc->mode_number].blockflag;
1129
1130     amplitude=get_bits(&vc->gb, vf->amplitude_bits);
1131     if (amplitude>0) {
1132         float last = 0;
1133         uint_fast16_t lsp_len = 0;
1134         uint_fast16_t idx;
1135         vorbis_codebook codebook;
1136
1137         book_idx=get_bits(&vc->gb, ilog(vf->num_books));
1138         if ( book_idx >= vf->num_books ) {
1139             av_log( vc->avccontext, AV_LOG_ERROR,
1140                     "floor0 dec: booknumber too high!\n" );
1141             //FIXME: look above
1142         }
1143         AV_DEBUG( "floor0 dec: booknumber: %u\n", book_idx );
1144         codebook=vc->codebooks[vf->book_list[book_idx]];
1145
1146         while (lsp_len<vf->order) {
1147             int vec_off;
1148
1149             AV_DEBUG( "floor0 dec: book dimension: %d\n", codebook.dimensions );
1150             AV_DEBUG( "floor0 dec: maximum depth: %d\n", codebook.maxdepth );
1151             /* read temp vector */
1152             vec_off=get_vlc2(&vc->gb,
1153                              codebook.vlc.table,
1154                              codebook.nb_bits,
1155                              codebook.maxdepth ) *
1156                              codebook.dimensions;
1157             AV_DEBUG( "floor0 dec: vector offset: %d\n", vec_off );
1158             /* copy each vector component and add last to it */
1159             for (idx=0; idx<codebook.dimensions; ++idx) {
1160                 lsp[lsp_len+idx]=codebook.codevectors[vec_off+idx]+last;
1161             }
1162             last=lsp[lsp_len+idx-1]; /* set last to last vector component */
1163
1164             lsp_len += codebook.dimensions;
1165         }
1166 #ifdef V_DEBUG
1167         /* DEBUG: output lsp coeffs */
1168         {
1169             int idx;
1170             for ( idx = 0; idx < lsp_len; ++idx )
1171                 AV_DEBUG("floor0 dec: coeff at %d is %f\n", idx, lsp[idx] );
1172         }
1173 #endif
1174
1175         /* synthesize floor output vector */
1176         {
1177             int i;
1178             int order=vf->order;
1179             float wstep=M_PI/vf->bark_map_size;
1180
1181             for(i=0;i<order;i++) { lsp[i]=2.0f*cos(lsp[i]); }
1182
1183             AV_DEBUG("floor0 synth: map_size=%d; m=%d; wstep=%f\n",
1184                      vf->map_size, order, wstep);
1185
1186             i=0;
1187             while(i<vf->map_size[blockflag]) {
1188                 int j, iter_cond=vf->map[blockflag][i];
1189                 float p=0.5f;
1190                 float q=0.5f;
1191                 float two_cos_w=2.0f*cos(wstep*iter_cond); // needed all times
1192
1193                 /* similar part for the q and p products */
1194                 for(j=0;j<order;j+=2) {
1195                     q *= lsp[j]  -two_cos_w;
1196                     p *= lsp[j+1]-two_cos_w;
1197                 }
1198                 if(j==order) { // even order
1199                     p *= p*(2.0f-two_cos_w);
1200                     q *= q*(2.0f+two_cos_w);
1201                 }
1202                 else { // odd order
1203                     q *= two_cos_w-lsp[j]; // one more time for q
1204
1205                     /* final step and square */
1206                     p *= p*(4.f-two_cos_w*two_cos_w);
1207                     q *= q;
1208                 }
1209
1210                 /* calculate linear floor value */
1211                 {
1212                     q=exp( (
1213                              ( (amplitude*vf->amplitude_offset)/
1214                                (((1<<vf->amplitude_bits)-1) * sqrt(p+q)) )
1215                              - vf->amplitude_offset ) * .11512925f
1216                          );
1217                 }
1218
1219                 /* fill vector */
1220                 do { vec[i]=q; ++i; }while(vf->map[blockflag][i]==iter_cond);
1221             }
1222         }
1223     }
1224     else {
1225         /* this channel is unused */
1226         return 1;
1227     }
1228
1229     AV_DEBUG(" Floor0 decoded\n");
1230
1231     return 0;
1232 }
1233 static uint_fast8_t vorbis_floor1_decode(vorbis_context *vc, vorbis_floor_data *vfu, float *vec) {
1234     vorbis_floor1 * vf=&vfu->t1;
1235     GetBitContext *gb=&vc->gb;
1236     uint_fast16_t range_v[4]={ 256, 128, 86, 64 };
1237     uint_fast16_t range=range_v[vf->multiplier-1];
1238     uint_fast16_t floor1_Y[vf->x_list_dim];
1239     uint_fast16_t floor1_Y_final[vf->x_list_dim];
1240     uint_fast8_t floor1_flag[vf->x_list_dim];
1241     uint_fast8_t class_;
1242     uint_fast8_t cdim;
1243     uint_fast8_t cbits;
1244     uint_fast8_t csub;
1245     uint_fast8_t cval;
1246     int_fast16_t book;
1247     uint_fast16_t offset;
1248     uint_fast16_t i,j;
1249     /*u*/int_fast16_t adx, ady, off, predicted; // WTF ? dy/adx= (unsigned)dy/adx ?
1250     int_fast16_t dy, err;
1251     uint_fast16_t lx,hx, ly, hy=0;
1252
1253
1254     if (!get_bits1(gb)) return 1; // silence
1255
1256 // Read values (or differences) for the floor's points
1257
1258     floor1_Y[0]=get_bits(gb, ilog(range-1));
1259     floor1_Y[1]=get_bits(gb, ilog(range-1));
1260
1261     AV_DEBUG("floor 0 Y %d floor 1 Y %d \n", floor1_Y[0], floor1_Y[1]);
1262
1263     offset=2;
1264     for(i=0;i<vf->partitions;++i) {
1265         class_=vf->partition_class[i];
1266         cdim=vf->class_dimensions[class_];
1267         cbits=vf->class_subclasses[class_];
1268         csub=(1<<cbits)-1;
1269         cval=0;
1270
1271         AV_DEBUG("Cbits %d \n", cbits);
1272
1273         if (cbits) { // this reads all subclasses for this partition's class
1274             cval=get_vlc2(gb, vc->codebooks[vf->class_masterbook[class_]].vlc.table,
1275             vc->codebooks[vf->class_masterbook[class_]].nb_bits, 3);
1276         }
1277
1278         for(j=0;j<cdim;++j) {
1279             book=vf->subclass_books[class_][cval & csub];
1280
1281             AV_DEBUG("book %d Cbits %d cval %d  bits:%d \n", book, cbits, cval, get_bits_count(gb));
1282
1283             cval=cval>>cbits;
1284             if (book>-1) {
1285                 floor1_Y[offset+j]=get_vlc2(gb, vc->codebooks[book].vlc.table,
1286                 vc->codebooks[book].nb_bits, 3);
1287             } else {
1288                 floor1_Y[offset+j]=0;
1289             }
1290
1291             AV_DEBUG(" floor(%d) = %d \n", vf->list[offset+j].x, floor1_Y[offset+j]);
1292         }
1293         offset+=cdim;
1294     }
1295
1296 // Amplitude calculation from the differences
1297
1298     floor1_flag[0]=1;
1299     floor1_flag[1]=1;
1300     floor1_Y_final[0]=floor1_Y[0];
1301     floor1_Y_final[1]=floor1_Y[1];
1302
1303     for(i=2;i<vf->x_list_dim;++i) {
1304         uint_fast16_t val, highroom, lowroom, room;
1305         uint_fast16_t high_neigh_offs;
1306         uint_fast16_t low_neigh_offs;
1307
1308         low_neigh_offs=vf->list[i].low;
1309         high_neigh_offs=vf->list[i].high;
1310         dy=floor1_Y_final[high_neigh_offs]-floor1_Y_final[low_neigh_offs];  // render_point begin
1311         adx=vf->list[high_neigh_offs].x-vf->list[low_neigh_offs].x;
1312         ady= ABS(dy);
1313         err=ady*(vf->list[i].x-vf->list[low_neigh_offs].x);
1314         off=(int16_t)err/(int16_t)adx;
1315         if (dy<0) {
1316             predicted=floor1_Y_final[low_neigh_offs]-off;
1317         } else {
1318             predicted=floor1_Y_final[low_neigh_offs]+off;
1319         } // render_point end
1320
1321         val=floor1_Y[i];
1322         highroom=range-predicted;
1323         lowroom=predicted;
1324         if (highroom < lowroom) {
1325             room=highroom*2;
1326         } else {
1327             room=lowroom*2;   // SPEC mispelling
1328         }
1329         if (val) {
1330             floor1_flag[low_neigh_offs]=1;
1331             floor1_flag[high_neigh_offs]=1;
1332             floor1_flag[i]=1;
1333             if (val>=room) {
1334                 if (highroom > lowroom) {
1335                     floor1_Y_final[i]=val-lowroom+predicted;
1336                 } else {
1337                     floor1_Y_final[i]=predicted-val+highroom-1;
1338                 }
1339             } else {
1340                 if (val & 1) {
1341                     floor1_Y_final[i]=predicted-(val+1)/2;
1342                 } else {
1343                     floor1_Y_final[i]=predicted+val/2;
1344                 }
1345             }
1346         } else {
1347             floor1_flag[i]=0;
1348             floor1_Y_final[i]=predicted;
1349         }
1350
1351         AV_DEBUG(" Decoded floor(%d) = %d / val %d \n", vf->list[i].x, floor1_Y_final[i], val);
1352     }
1353
1354 // Curve synth - connect the calculated dots and convert from dB scale FIXME optimize ?
1355
1356     hx=0;
1357     lx=0;
1358     ly=floor1_Y_final[0]*vf->multiplier;  // conforms to SPEC
1359
1360     vec[0]=ff_vorbis_floor1_inverse_db_table[ly];
1361
1362     for(i=1;i<vf->x_list_dim;++i) {
1363         AV_DEBUG(" Looking at post %d \n", i);
1364
1365         if (floor1_flag[vf->list[i].sort]) {   // SPEC mispelled
1366             hy=floor1_Y_final[vf->list[i].sort]*vf->multiplier;
1367             hx=vf->list[vf->list[i].sort].x;
1368
1369             render_line(lx, ly, hx, hy, vec, vc->blocksize[1]);
1370
1371             lx=hx;
1372             ly=hy;
1373         }
1374     }
1375
1376     if (hx<vf->list[1].x) {
1377         render_line(hx, hy, vf->list[1].x, hy, vec, vc->blocksize[1]);
1378     }
1379
1380     AV_DEBUG(" Floor decoded\n");
1381
1382     return 0;
1383 }
1384
1385 // Read and decode residue
1386
1387 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) {
1388     GetBitContext *gb=&vc->gb;
1389     uint_fast8_t c_p_c=vc->codebooks[vr->classbook].dimensions;
1390     uint_fast16_t n_to_read=vr->end-vr->begin;
1391     uint_fast16_t ptns_to_read=n_to_read/vr->partition_size;
1392     uint_fast8_t classifs[ptns_to_read*vc->audio_channels];
1393     uint_fast8_t pass;
1394     uint_fast8_t ch_used;
1395     uint_fast8_t i,j,l;
1396     uint_fast16_t k;
1397
1398     if (vr->type==2) {
1399         for(j=1;j<ch;++j) {
1400                 do_not_decode[0]&=do_not_decode[j];  // FIXME - clobbering input
1401         }
1402         if (do_not_decode[0]) return 0;
1403         ch_used=1;
1404     } else {
1405         ch_used=ch;
1406     }
1407
1408     AV_DEBUG(" residue type 0/1/2 decode begin, ch: %d  cpc %d  \n", ch, c_p_c);
1409
1410     for(pass=0;pass<=vr->maxpass;++pass) { // FIXME OPTIMIZE?
1411         uint_fast16_t voffset;
1412         uint_fast16_t partition_count;
1413         uint_fast16_t j_times_ptns_to_read;
1414
1415         voffset=vr->begin;
1416         for(partition_count=0;partition_count<ptns_to_read;) {  // SPEC        error
1417             if (!pass) {
1418                 uint_fast32_t inverse_class = inverse[vr->classifications];
1419                 for(j_times_ptns_to_read=0, j=0;j<ch_used;++j) {
1420                     if (!do_not_decode[j]) {
1421                         uint_fast32_t temp=get_vlc2(gb, vc->codebooks[vr->classbook].vlc.table,
1422                         vc->codebooks[vr->classbook].nb_bits, 3);
1423
1424                         AV_DEBUG("Classword: %d \n", temp);
1425
1426                         assert(vr->classifications > 1 && temp<=65536); //needed for inverse[]
1427                         for(i=0;i<c_p_c;++i) {
1428                             uint_fast32_t temp2;
1429
1430                             temp2=(((uint_fast64_t)temp) * inverse_class)>>32;
1431                             if (partition_count+c_p_c-1-i < ptns_to_read) {
1432                                 classifs[j_times_ptns_to_read+partition_count+c_p_c-1-i]=temp-temp2*vr->classifications;
1433                             }
1434                             temp=temp2;
1435                         }
1436                     }
1437                     j_times_ptns_to_read+=ptns_to_read;
1438                 }
1439             }
1440             for(i=0;(i<c_p_c) && (partition_count<ptns_to_read);++i) {
1441                 for(j_times_ptns_to_read=0, j=0;j<ch_used;++j) {
1442                     uint_fast16_t voffs;
1443
1444                     if (!do_not_decode[j]) {
1445                         uint_fast8_t vqclass=classifs[j_times_ptns_to_read+partition_count];
1446                         int_fast16_t vqbook=vr->books[vqclass][pass];
1447
1448                         if (vqbook>=0) {
1449                             uint_fast16_t coffs;
1450                             unsigned dim= vc->codebooks[vqbook].dimensions; // not uint_fast8_t: 64bit is slower here on amd64
1451                             uint_fast16_t step= dim==1 ? vr->partition_size
1452                                               : FASTDIV(vr->partition_size, dim);
1453                             vorbis_codebook codebook= vc->codebooks[vqbook];
1454
1455                             if (vr->type==0) {
1456
1457                                 voffs=voffset+j*vlen;
1458                                 for(k=0;k<step;++k) {
1459                                     coffs=get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * dim;
1460                                     for(l=0;l<dim;++l) {
1461                                         vec[voffs+k+l*step]+=codebook.codevectors[coffs+l];  // FPMATH
1462                                     }
1463                                 }
1464                             }
1465                             else if (vr->type==1) {
1466                                 voffs=voffset+j*vlen;
1467                                 for(k=0;k<step;++k) {
1468                                     coffs=get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * dim;
1469                                     for(l=0;l<dim;++l, ++voffs) {
1470                                         vec[voffs]+=codebook.codevectors[coffs+l];  // FPMATH
1471
1472                                         AV_DEBUG(" pass %d offs: %d curr: %f change: %f cv offs.: %d  \n", pass, voffs, vec[voffs], codebook.codevectors[coffs+l], coffs);
1473                                     }
1474                                 }
1475                             }
1476                             else if (vr->type==2 && ch==2 && (voffset&1)==0 && (dim&1)==0) { // most frequent case optimized
1477                                 voffs=voffset>>1;
1478
1479                                 if(dim==2) {
1480                                     for(k=0;k<step;++k) {
1481                                         coffs=get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * 2;
1482                                         vec[voffs+k     ]+=codebook.codevectors[coffs  ];  // FPMATH
1483                                         vec[voffs+k+vlen]+=codebook.codevectors[coffs+1];  // FPMATH
1484                                     }
1485                                 } else
1486                                 for(k=0;k<step;++k) {
1487                                     coffs=get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * dim;
1488                                     for(l=0;l<dim;l+=2, voffs++) {
1489                                         vec[voffs     ]+=codebook.codevectors[coffs+l  ];  // FPMATH
1490                                         vec[voffs+vlen]+=codebook.codevectors[coffs+l+1];  // FPMATH
1491
1492                                         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);
1493                                     }
1494                                 }
1495
1496                             }
1497                             else if (vr->type==2) {
1498                                 voffs=voffset;
1499
1500                                 for(k=0;k<step;++k) {
1501                                     coffs=get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * dim;
1502                                     for(l=0;l<dim;++l, ++voffs) {
1503                                         vec[voffs/ch+(voffs%ch)*vlen]+=codebook.codevectors[coffs+l];  // FPMATH FIXME use if and counter instead of / and %
1504
1505                                         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);
1506                                     }
1507                                 }
1508                             } else {
1509                                 av_log(vc->avccontext, AV_LOG_ERROR, " Invalid residue type while residue decode?! \n");
1510                                 return 1;
1511                             }
1512                         }
1513                     }
1514                     j_times_ptns_to_read+=ptns_to_read;
1515                 }
1516                 ++partition_count;
1517                 voffset+=vr->partition_size;
1518             }
1519         }
1520     }
1521     return 0;
1522 }
1523
1524 void vorbis_inverse_coupling(float *mag, float *ang, int blocksize)
1525 {
1526     int i;
1527     for(i=0; i<blocksize; i++)
1528     {
1529         if (mag[i]>0.0) {
1530             if (ang[i]>0.0) {
1531                 ang[i]=mag[i]-ang[i];
1532             } else {
1533                 float temp=ang[i];
1534                 ang[i]=mag[i];
1535                 mag[i]+=temp;
1536             }
1537         } else {
1538             if (ang[i]>0.0) {
1539                 ang[i]+=mag[i];
1540             } else {
1541                 float temp=ang[i];
1542                 ang[i]=mag[i];
1543                 mag[i]-=temp;
1544             }
1545         }
1546     }
1547 }
1548
1549 // Decode the audio packet using the functions above
1550
1551 static int vorbis_parse_audio_packet(vorbis_context *vc) {
1552     GetBitContext *gb=&vc->gb;
1553
1554     uint_fast8_t previous_window=0,next_window=0;
1555     uint_fast8_t mode_number;
1556     uint_fast16_t blocksize;
1557     int_fast32_t i,j;
1558     uint_fast8_t no_residue[vc->audio_channels];
1559     uint_fast8_t do_not_decode[vc->audio_channels];
1560     vorbis_mapping *mapping;
1561     float *ch_res_ptr=vc->channel_residues;
1562     float *ch_floor_ptr=vc->channel_floors;
1563     uint_fast8_t res_chan[vc->audio_channels];
1564     uint_fast8_t res_num=0;
1565     int_fast16_t retlen=0;
1566     uint_fast16_t saved_start=0;
1567     float fadd_bias = vc->add_bias;
1568
1569     if (get_bits1(gb)) {
1570         av_log(vc->avccontext, AV_LOG_ERROR, "Not a Vorbis I audio packet.\n");
1571         return -1; // packet type not audio
1572     }
1573
1574     if (vc->mode_count==1) {
1575         mode_number=0;
1576     } else {
1577         mode_number=get_bits(gb, ilog(vc->mode_count-1));
1578     }
1579     vc->mode_number=mode_number;
1580     mapping=&vc->mappings[vc->modes[mode_number].mapping];
1581
1582     AV_DEBUG(" Mode number: %d , mapping: %d , blocktype %d \n", mode_number, vc->modes[mode_number].mapping, vc->modes[mode_number].blockflag);
1583
1584     if (vc->modes[mode_number].blockflag) {
1585         previous_window=get_bits1(gb);
1586         next_window=get_bits1(gb);
1587     }
1588
1589     blocksize=vc->blocksize[vc->modes[mode_number].blockflag];
1590     memset(ch_res_ptr, 0, sizeof(float)*vc->audio_channels*blocksize/2); //FIXME can this be removed ?
1591     memset(ch_floor_ptr, 0, sizeof(float)*vc->audio_channels*blocksize/2); //FIXME can this be removed ?
1592
1593 // Decode floor
1594
1595     for(i=0;i<vc->audio_channels;++i) {
1596         vorbis_floor *floor;
1597         if (mapping->submaps>1) {
1598             floor=&vc->floors[mapping->submap_floor[mapping->mux[i]]];
1599         } else {
1600             floor=&vc->floors[mapping->submap_floor[0]];
1601         }
1602
1603         no_residue[i]=floor->decode(vc, &floor->data, ch_floor_ptr);
1604         ch_floor_ptr+=blocksize/2;
1605     }
1606
1607 // Nonzero vector propagate
1608
1609     for(i=mapping->coupling_steps-1;i>=0;--i) {
1610         if (!(no_residue[mapping->magnitude[i]] & no_residue[mapping->angle[i]])) {
1611             no_residue[mapping->magnitude[i]]=0;
1612             no_residue[mapping->angle[i]]=0;
1613         }
1614     }
1615
1616 // Decode residue
1617
1618     for(i=0;i<mapping->submaps;++i) {
1619         vorbis_residue *residue;
1620         uint_fast8_t ch=0;
1621
1622         for(j=0;j<vc->audio_channels;++j) {
1623             if ((mapping->submaps==1) || (i=mapping->mux[j])) {
1624                 res_chan[j]=res_num;
1625                 if (no_residue[j]) {
1626                     do_not_decode[ch]=1;
1627                 } else {
1628                     do_not_decode[ch]=0;
1629                 }
1630                 ++ch;
1631                 ++res_num;
1632             }
1633         }
1634         residue=&vc->residues[mapping->submap_residue[i]];
1635         vorbis_residue_decode(vc, residue, ch, do_not_decode, ch_res_ptr, blocksize/2);
1636
1637         ch_res_ptr+=ch*blocksize/2;
1638     }
1639
1640 // Inverse coupling
1641
1642     for(i=mapping->coupling_steps-1;i>=0;--i) { //warning: i has to be signed
1643         float *mag, *ang;
1644
1645         mag=vc->channel_residues+res_chan[mapping->magnitude[i]]*blocksize/2;
1646         ang=vc->channel_residues+res_chan[mapping->angle[i]]*blocksize/2;
1647         vc->dsp.vorbis_inverse_coupling(mag, ang, blocksize/2);
1648     }
1649
1650 // Dotproduct
1651
1652     for(j=0, ch_floor_ptr=vc->channel_floors;j<vc->audio_channels;++j,ch_floor_ptr+=blocksize/2) {
1653         ch_res_ptr=vc->channel_residues+res_chan[j]*blocksize/2;
1654         vc->dsp.vector_fmul(ch_floor_ptr, ch_res_ptr, blocksize/2);
1655     }
1656
1657 // MDCT, overlap/add, save data for next overlapping  FPMATH
1658
1659     for(j=0;j<vc->audio_channels;++j) {
1660         uint_fast8_t step=vc->audio_channels;
1661         uint_fast16_t k;
1662         float *saved=vc->saved+j*vc->blocksize[1]/2;
1663         float *ret=vc->ret;
1664         const float *lwin=vc->win[1];
1665         const float *swin=vc->win[0];
1666         float *buf=vc->buf;
1667         float *buf_tmp=vc->buf_tmp;
1668
1669         ch_floor_ptr=vc->channel_floors+j*blocksize/2;
1670
1671         saved_start=vc->saved_start;
1672
1673         vc->mdct[0].fft.imdct_calc(&vc->mdct[vc->modes[mode_number].blockflag], buf, ch_floor_ptr, buf_tmp);
1674
1675         //FIXME process channels together, to allow faster simd vector_fmul_add_add?
1676         if (vc->modes[mode_number].blockflag) {
1677             // -- overlap/add
1678             if (previous_window) {
1679                 vc->dsp.vector_fmul_add_add(ret+j, buf, lwin, saved, vc->add_bias, vc->blocksize[1]/2, step);
1680                 retlen=vc->blocksize[1]/2;
1681             } else {
1682                 int len = (vc->blocksize[1]-vc->blocksize[0])/4;
1683                 buf += len;
1684                 vc->dsp.vector_fmul_add_add(ret+j, buf, swin, saved, vc->add_bias, vc->blocksize[0]/2, step);
1685                 k = vc->blocksize[0]/2*step + j;
1686                 buf += vc->blocksize[0]/2;
1687                 if(vc->exp_bias){
1688                     for(i=0; i<len; i++, k+=step)
1689                         ((uint32_t*)ret)[k] = ((uint32_t*)buf)[i] + vc->exp_bias; // ret[k]=buf[i]*(1<<bias)
1690                 } else {
1691                     for(i=0; i<len; i++, k+=step)
1692                         ret[k] = buf[i] + fadd_bias;
1693                 }
1694                 buf=vc->buf;
1695                 retlen=vc->blocksize[0]/2+len;
1696             }
1697             // -- save
1698             if (next_window) {
1699                 buf += vc->blocksize[1]/2;
1700                 vc->dsp.vector_fmul_reverse(saved, buf, lwin, vc->blocksize[1]/2);
1701                 saved_start=0;
1702             } else {
1703                 saved_start=(vc->blocksize[1]-vc->blocksize[0])/4;
1704                 buf += vc->blocksize[1]/2;
1705                 for(i=0; i<saved_start; i++)
1706                     ((uint32_t*)saved)[i] = ((uint32_t*)buf)[i] + vc->exp_bias;
1707                 vc->dsp.vector_fmul_reverse(saved+saved_start, buf+saved_start, swin, vc->blocksize[0]/2);
1708             }
1709         } else {
1710             // --overlap/add
1711             if(vc->add_bias) {
1712                 for(k=j, i=0;i<saved_start;++i, k+=step)
1713                     ret[k] = saved[i] + fadd_bias;
1714             } else {
1715                 for(k=j, i=0;i<saved_start;++i, k+=step)
1716                     ret[k] = saved[i];
1717             }
1718             vc->dsp.vector_fmul_add_add(ret+k, buf, swin, saved+saved_start, vc->add_bias, vc->blocksize[0]/2, step);
1719             retlen=saved_start+vc->blocksize[0]/2;
1720             // -- save
1721             buf += vc->blocksize[0]/2;
1722             vc->dsp.vector_fmul_reverse(saved, buf, swin, vc->blocksize[0]/2);
1723             saved_start=0;
1724         }
1725     }
1726     vc->saved_start=saved_start;
1727
1728     return retlen*vc->audio_channels;
1729 }
1730
1731 // Return the decoded audio packet through the standard api
1732
1733 static int vorbis_decode_frame(AVCodecContext *avccontext,
1734                         void *data, int *data_size,
1735                         uint8_t *buf, int buf_size)
1736 {
1737     vorbis_context *vc = avccontext->priv_data ;
1738     GetBitContext *gb = &(vc->gb);
1739
1740     int_fast16_t len;
1741
1742     if(!buf_size){
1743         return 0;
1744     }
1745
1746     AV_DEBUG("packet length %d \n", buf_size);
1747
1748     init_get_bits(gb, buf, buf_size*8);
1749
1750     len=vorbis_parse_audio_packet(vc);
1751
1752     if (len<=0) {
1753         *data_size=0;
1754         return buf_size;
1755     }
1756
1757     if (!vc->first_frame) {
1758         vc->first_frame=1;
1759         *data_size=0;
1760         return buf_size ;
1761     }
1762
1763     AV_DEBUG("parsed %d bytes %d bits, returned %d samples (*ch*bits) \n", get_bits_count(gb)/8, get_bits_count(gb)%8, len);
1764
1765     vc->dsp.float_to_int16(data, vc->ret, len);
1766     *data_size=len*2;
1767
1768     return buf_size ;
1769 }
1770
1771 // Close decoder
1772
1773 static int vorbis_decode_close(AVCodecContext *avccontext) {
1774     vorbis_context *vc = avccontext->priv_data;
1775
1776     vorbis_free(vc);
1777
1778     return 0 ;
1779 }
1780
1781 AVCodec vorbis_decoder = {
1782     "vorbis",
1783     CODEC_TYPE_AUDIO,
1784     CODEC_ID_VORBIS,
1785     sizeof(vorbis_context),
1786     vorbis_decode_init,
1787     NULL,
1788     vorbis_decode_close,
1789     vorbis_decode_frame,
1790 };
1791