1 /********************************************************************
3 * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE. *
4 * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS *
5 * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
6 * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. *
8 * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2002 *
9 * by the XIPHOPHORUS Company http://www.xiph.org/ *
11 ********************************************************************
13 function: bitrate tracking and management
14 last mod: $Id: bitrate.c,v 1.12 2002/06/14 17:14:58 msmith Exp $
16 ********************************************************************/
23 #include "vorbis/codec.h"
24 #include "codec_internal.h"
30 static long BINBITS(bitrate_manager_state *bm,long pos,long inbin){
31 int bins=bm->queue_bins;
32 int bin=((inbin&0x7fffffffUL)>>BITTRACK_BPT);
33 ogg_uint32_t lobits=0;
34 ogg_uint32_t hibits=0;
37 if(bin>0)lobits=bm->queue_binned[pos*bins+bin-1];
39 hibits=bm->queue_binned[pos*bins+bin];
45 return(lobits+bitdel*(inbin&((1<<BITTRACK_BPT)-1))/(1<<BITTRACK_BPT));
49 #define LIMITBITS(pos,bin) ((bin)>-bins?\
50 bm->minmax_binstack[(pos)*bins*2+((bin)+bins)-1]:0)
52 static long LACING_ADJUST(long bits){
53 int addto=((bits+7)/8+1)/256+1;
54 return( ((bits+7)/8+addto)*8 );
57 static double floater_interpolate(bitrate_manager_state *bm,vorbis_info *vi,
59 int bin=bm->avgfloat*BITTRACK_DIVISOR-1.;
63 lobitrate=(double)(bin==0?0:bm->avg_binacc[bin-1])/bm->avg_sampleacc*vi->rate;
64 while(lobitrate>desired_rate && bin>0){
66 lobitrate=(double)(bin==0?0:bm->avg_binacc[bin-1])/bm->avg_sampleacc*vi->rate;
69 hibitrate=(double)(bin>=bm->queue_bins?bm->avg_binacc[bm->queue_bins-1]:
70 bm->avg_binacc[bin])/bm->avg_sampleacc*vi->rate;
71 while(hibitrate<desired_rate && bin<bm->queue_bins){
73 if(bin<bm->queue_bins)
74 hibitrate=(double)bm->avg_binacc[bin]/bm->avg_sampleacc*vi->rate;
78 if(bin==bm->queue_bins){
79 return bin/(double)BITTRACK_DIVISOR;
81 double delta=(desired_rate-lobitrate)/(hibitrate-lobitrate);
82 return (bin+delta)/BITTRACK_DIVISOR;
86 /* try out a new limit */
87 static long limit_sum(bitrate_manager_state *bm,int limit){
88 int i=bm->minmax_stackptr;
89 long acc=bm->minmax_acctotal;
90 long bins=bm->queue_bins;
93 acc+=LIMITBITS(i,limit);
96 if(bm->minmax_limitstack[i]<=limit)break;
97 acc-=LIMITBITS(i,bm->minmax_limitstack[i]);
98 acc+=LIMITBITS(i,limit);
103 /* compute bitrate tracking setup, allocate circular packet size queue */
104 void vorbis_bitrate_init(vorbis_info *vi,bitrate_manager_state *bm){
106 codec_setup_info *ci=vi->codec_setup;
107 bitrate_manager_info *bi=&ci->bi;
110 memset(bm,0,sizeof(*bm));
114 bm->avg_sampledesired=bi->queue_avg_time*vi->rate;
115 bm->avg_centerdesired=bi->queue_avg_time*vi->rate*bi->queue_avg_center;
116 bm->minmax_sampledesired=bi->queue_minmax_time*vi->rate;
118 /* first find the max possible needed queue size */
119 maxlatency=max(bm->avg_sampledesired-bm->avg_centerdesired,
120 bm->minmax_sampledesired)+bm->avg_centerdesired;
123 (bi->queue_avgmin>0 || bi->queue_avgmax>0 || bi->queue_hardmax>0 ||
124 bi->queue_hardmin>0)){
125 long maxpackets=maxlatency/(ci->blocksizes[0]>>1)+3;
126 long bins=BITTRACK_DIVISOR*ci->passlimit[ci->coupling_passes-1];
128 bm->queue_size=maxpackets;
130 bm->queue_binned=_ogg_malloc(maxpackets*bins*sizeof(*bm->queue_binned));
131 bm->queue_actual=_ogg_malloc(maxpackets*sizeof(*bm->queue_actual));
133 if((bi->queue_avgmin>0 || bi->queue_avgmax>0) &&
134 bi->queue_avg_time>0){
136 bm->avg_binacc=_ogg_calloc(bins,sizeof(*bm->avg_binacc));
137 bm->avgfloat=bi->avgfloat_initial;
144 if((bi->queue_hardmin>0 || bi->queue_hardmax>0) &&
145 bi->queue_minmax_time>0){
147 bm->minmax_binstack=_ogg_calloc((bins+1)*bins*2,
148 sizeof(bm->minmax_binstack));
149 bm->minmax_posstack=_ogg_calloc((bins+1),
150 sizeof(bm->minmax_posstack));
151 bm->minmax_limitstack=_ogg_calloc((bins+1),
152 sizeof(bm->minmax_limitstack));
157 /* space for the packet queueing */
158 bm->queue_packet_buffers=_ogg_calloc(maxpackets,sizeof(*bm->queue_packet_buffers));
159 bm->queue_packets=_ogg_calloc(maxpackets,sizeof(*bm->queue_packets));
160 for(i=0;i<maxpackets;i++)
161 oggpack_writeinit(bm->queue_packet_buffers+i);
164 bm->queue_packet_buffers=_ogg_calloc(1,sizeof(*bm->queue_packet_buffers));
165 bm->queue_packets=_ogg_calloc(1,sizeof(*bm->queue_packets));
166 oggpack_writeinit(bm->queue_packet_buffers);
171 void vorbis_bitrate_clear(bitrate_manager_state *bm){
174 if(bm->queue_binned)_ogg_free(bm->queue_binned);
175 if(bm->queue_actual)_ogg_free(bm->queue_actual);
176 if(bm->avg_binacc)_ogg_free(bm->avg_binacc);
177 if(bm->minmax_binstack)_ogg_free(bm->minmax_binstack);
178 if(bm->minmax_posstack)_ogg_free(bm->minmax_posstack);
179 if(bm->minmax_limitstack)_ogg_free(bm->minmax_limitstack);
180 if(bm->queue_packet_buffers){
181 if(bm->queue_size==0){
182 oggpack_writeclear(bm->queue_packet_buffers);
183 _ogg_free(bm->queue_packet_buffers);
185 for(i=0;i<bm->queue_size;i++)
186 oggpack_writeclear(bm->queue_packet_buffers+i);
187 _ogg_free(bm->queue_packet_buffers);
190 if(bm->queue_packets)_ogg_free(bm->queue_packets);
191 memset(bm,0,sizeof(*bm));
195 int vorbis_bitrate_managed(vorbis_block *vb){
196 vorbis_dsp_state *vd=vb->vd;
197 backend_lookup_state *b=vd->backend_state;
198 bitrate_manager_state *bm=&b->bms;
200 if(bm->queue_binned)return(1);
204 int vorbis_bitrate_maxmarkers(void){
205 return 8*BITTRACK_DIVISOR;
208 /* finish taking in the block we just processed */
209 int vorbis_bitrate_addblock(vorbis_block *vb){
211 vorbis_block_internal *vbi=vb->internal;
212 vorbis_dsp_state *vd=vb->vd;
213 backend_lookup_state *b=vd->backend_state;
214 bitrate_manager_state *bm=&b->bms;
215 vorbis_info *vi=vd->vi;
216 codec_setup_info *ci=vi->codec_setup;
217 bitrate_manager_info *bi=&ci->bi;
218 int eofflag=vb->eofflag;
219 int head=bm->queue_head;
220 int next_head=head+1;
221 int bins=bm->queue_bins;
222 int minmax_head,new_minmax_head;
224 ogg_uint32_t *head_ptr;
227 if(!bm->queue_binned){
229 /* not a bitrate managed stream, but for API simplicity, we'll
230 buffer one packet to keep the code path clean */
232 if(bm->queue_head)return(-1); /* one has been submitted without
236 bm->queue_packets[0].packet=oggpack_get_buffer(&vb->opb);
237 bm->queue_packets[0].bytes=oggpack_bytes(&vb->opb);
238 bm->queue_packets[0].b_o_s=0;
239 bm->queue_packets[0].e_o_s=vb->eofflag;
240 bm->queue_packets[0].granulepos=vb->granulepos;
241 bm->queue_packets[0].packetno=vb->sequence; /* for sake of completeness */
243 memcpy(&temp,bm->queue_packet_buffers,sizeof(vb->opb));
244 memcpy(bm->queue_packet_buffers,&vb->opb,sizeof(vb->opb));
245 memcpy(&vb->opb,&temp,sizeof(vb->opb));
250 /* add encoded packet to head */
251 if(next_head>=bm->queue_size)next_head=0;
252 head_ptr=bm->queue_binned+bins*head;
254 /* is there room to add a block? In proper use of the API, this will
255 never come up... but guard it anyway */
256 if(next_head==bm->avg_tail || next_head==bm->minmax_tail)return(-1);
258 /* add the block to the toplevel queue */
259 bm->queue_head=next_head;
260 bm->queue_actual[head]=(vb->W?0x80000000UL:0);
262 /* buffer packet fields */
263 bm->queue_packets[head].packet=oggpack_get_buffer(&vb->opb);
264 bm->queue_packets[head].bytes=oggpack_bytes(&vb->opb);
265 bm->queue_packets[head].b_o_s=0;
266 bm->queue_packets[head].e_o_s=vb->eofflag;
267 bm->queue_packets[head].granulepos=vb->granulepos;
268 bm->queue_packets[head].packetno=vb->sequence; /* for sake of completeness */
270 /* swap packet buffers */
271 memcpy(&temp,bm->queue_packet_buffers+head,sizeof(vb->opb));
272 memcpy(bm->queue_packet_buffers+head,&vb->opb,sizeof(vb->opb));
273 memcpy(&vb->opb,&temp,sizeof(vb->opb));
276 memcpy(head_ptr,vbi->packet_markers,sizeof(*head_ptr)*bins);
279 new_minmax_head=minmax_head=bm->avg_center;
281 new_minmax_head=minmax_head=head;
283 /* the average tracking queue is updated first; its results (if it's
284 in use) are taken into account by the min/max limiter (if min/max
287 unsigned long desired_center=bm->avg_centerdesired;
288 if(eofflag)desired_center=0;
290 /* update the avg head */
292 bm->avg_binacc[i]+=LACING_ADJUST(head_ptr[i]);
293 bm->avg_sampleacc+=ci->blocksizes[vb->W]>>1;
294 bm->avg_centeracc+=ci->blocksizes[vb->W]>>1;
296 if(bm->avg_sampleacc>bm->avg_sampledesired || eofflag){
298 /* update the avg center */
299 if(bm->avg_centeracc>desired_center){
300 /* choose the new average floater */
301 int samples=ci->blocksizes[vb->W]>>1;
302 double upper=floater_interpolate(bm,vi,bi->queue_avgmax);
303 double lower=floater_interpolate(bm,vi,bi->queue_avgmin);
304 double new=bi->avgfloat_initial,slew;
307 if(upper>0. && upper<new)new=upper;
308 if(lower<bi->avgfloat_minimum)
309 lower=bi->avgfloat_minimum;
310 if(lower>new)new=lower;
312 slew=(new-bm->avgfloat)/samples*vi->rate;
314 if(slew<bi->avgfloat_downslew_max)
315 new=bm->avgfloat+bi->avgfloat_downslew_max/vi->rate*samples;
316 if(slew>bi->avgfloat_upslew_max)
317 new=bm->avgfloat+bi->avgfloat_upslew_max/vi->rate*samples;
321 /* apply the average floater to new blocks */
322 bin=bm->avgfloat*(BITTRACK_DIVISOR<<BITTRACK_BPT);
324 while(bm->avg_centeracc>desired_center){
325 samples=ci->blocksizes[bm->queue_actual[bm->avg_center]&
326 0x80000000UL?1:0]>>1;
328 bm->queue_actual[bm->avg_center]|=bin;
330 bm->avg_centeracc-=samples;
332 if(bm->noisetrigger_postpone)bm->noisetrigger_postpone-=samples;
333 if(bm->avg_center>=bm->queue_size)bm->avg_center=0;
335 new_minmax_head=bm->avg_center;
337 /* track noise bias triggers and noise bias */
338 if(bm->avgfloat<bi->avgfloat_noise_lowtrigger)
339 bm->noisetrigger_request+=1.f;
341 if(bm->noisetrigger_request>0. && bm->avgnoise>0.)
342 bm->noisetrigger_request-=.2f;
344 if(bm->avgfloat>bi->avgfloat_noise_hightrigger)
345 bm->noisetrigger_request-=1.f;
347 if(bm->noisetrigger_request<0 && bm->avgnoise<0.)
348 bm->noisetrigger_request+=.2f;
350 if(bm->noisetrigger_postpone<=0){
351 if(bm->noisetrigger_request<0.){
353 if(-bm->noisetrigger_request>(signed long)(bm->avg_sampleacc)/2)
355 bm->noisetrigger_postpone=bm->avg_sampleacc/2;
357 if(bm->noisetrigger_request>0.){
359 if(bm->noisetrigger_request>(signed long)(bm->avg_sampleacc)/2)
361 bm->noisetrigger_postpone=bm->avg_sampleacc/2;
364 /* we generally want the noise bias to drift back to zero */
365 bm->noisetrigger_request=0.f;
367 bm->noisetrigger_request= -1.;
369 bm->noisetrigger_request= +1.;
371 if(bm->avgnoise<bi->avgfloat_noise_minval)
372 bm->avgnoise=bi->avgfloat_noise_minval;
373 if(bm->avgnoise>bi->avgfloat_noise_maxval)
374 bm->avgnoise=bi->avgfloat_noise_maxval;
378 /* update the avg tail if needed */
379 while(bm->avg_sampleacc>bm->avg_sampledesired){
381 ci->blocksizes[bm->queue_actual[bm->avg_tail]&0x80000000UL?1:0]>>1;
382 for(i=0;i<bm->queue_bins;i++)
383 bm->avg_binacc[i]-=LACING_ADJUST(bm->queue_binned[bins*bm->avg_tail+i]);
384 bm->avg_sampleacc-=samples;
386 if(bm->avg_tail>=bm->queue_size)bm->avg_tail=0;
392 /* if we're not using an average tracker, the 'float' is nailed to
393 the avgfloat_initial value. It needs to be set for the min/max
395 long bin=bi->avgfloat_initial*(BITTRACK_DIVISOR<<BITTRACK_BPT);
396 bm->queue_actual[head]|=bin;
397 new_minmax_head=next_head;
400 /* update the min/max queues and enforce limits */
401 if(bm->minmax_binstack){
402 unsigned long sampledesired=eofflag?0:bm->minmax_sampledesired;
404 /* add to stack recent */
405 while(minmax_head!=new_minmax_head){
407 int samples=ci->blocksizes[bm->queue_actual[minmax_head]&
408 0x80000000UL?1:0]>>1;
410 /* the construction here is not parallel to the floater's
413 floater[bin-1] <-> floater supported at bin
415 floater[0] <-> floater supported at 1
416 supported at zero is implicit.
417 the BINBITS macro performs offsetting
420 bin minmax[bin*2-1] <-> floater supported at bin
422 1 minmax[bin] <-> floater supported at 1
423 0 minmax[bin-1] <-> no limit/support (limited to/supported at bin 0,
425 -1 minmax[bin-2] <-> floater limited to bin-1
427 -bin+1 minmax[0] <-> floater limited to 1
428 limited to zero (val= -bin) is implicit
430 for(i=0;i<(unsigned int)bins;i++){
431 bm->minmax_binstack[bm->minmax_stackptr*bins*2+bins+i]+=
433 BINBITS(bm,minmax_head,
434 (bm->queue_actual[minmax_head]&0x7fffffffUL)>
435 ((i+1)<<BITTRACK_BPT)?
436 bm->queue_actual[minmax_head]:
437 ((i+1)<<BITTRACK_BPT)));
439 bm->minmax_binstack[bm->minmax_stackptr*bins*2+i]+=
441 BINBITS(bm,minmax_head,
442 (bm->queue_actual[minmax_head]&0x7fffffffUL)<
443 ((i+1)<<BITTRACK_BPT)?
444 bm->queue_actual[minmax_head]:
445 ((i+1)<<BITTRACK_BPT)));
448 bm->minmax_posstack[bm->minmax_stackptr]=minmax_head; /* not one
452 bm->minmax_limitstack[bm->minmax_stackptr]=0;
453 bm->minmax_sampleacc+=samples;
454 bm->minmax_acctotal+=
455 LACING_ADJUST(BINBITS(bm,minmax_head,bm->queue_actual[minmax_head]));
458 if(minmax_head>=bm->queue_size)minmax_head=0;
461 /* check limits, enforce changes */
462 if(bm->minmax_sampleacc>sampledesired){
463 double bitrate=(double)bm->minmax_acctotal/bm->minmax_sampleacc*vi->rate;
466 if((bi->queue_hardmax>0 && bitrate>bi->queue_hardmax) ||
467 (bi->queue_hardmin>0 && bitrate<bi->queue_hardmin)){
470 long bitsum=limit_sum(bm,0);
472 bitrate=(double)bitsum/bm->minmax_sampleacc*vi->rate;
474 /* we're off rate. Iteratively try out new hard floater
475 limits until we find one that brings us inside. Here's
476 where we see the whole point of the limit stacks. */
477 if(bi->queue_hardmax>0 && bitrate>bi->queue_hardmax){
478 for(limit=-1;limit>-bins;limit--){
479 long bitsum=limit_sum(bm,limit);
480 bitrate=(double)bitsum/bm->minmax_sampleacc*vi->rate;
481 if(bitrate<=bi->queue_hardmax)break;
483 }else if(bitrate<bi->queue_hardmin){
484 for(limit=1;limit<bins;limit++){
485 long bitsum=limit_sum(bm,limit);
486 bitrate=(double)bitsum/bm->minmax_sampleacc*vi->rate;
487 if(bitrate>=bi->queue_hardmin)break;
489 if(bitrate>bi->queue_hardmax)limit--;
492 for(i=limit-1;i>-bins;i--){
493 long bitsum=limit_sum(bm,i);
494 bitrate=(double)bitsum/bm->minmax_sampleacc*vi->rate;
497 bitsum=limit_sum(bm,limit);
498 bitrate=(double)bitsum/bm->minmax_sampleacc*vi->rate;
500 /* trace the limit backward, stop when we see a lower limit */
501 newstack=bm->minmax_stackptr-1;
503 if(bm->minmax_limitstack[newstack]<limit)break;
507 /* update bit counter with new limit and replace any stack
508 limits that have been replaced by our new lower limit */
509 stackctr=bm->minmax_stackptr;
510 while(stackctr>newstack){
511 bm->minmax_acctotal-=
512 LIMITBITS(stackctr,bm->minmax_limitstack[stackctr]);
513 bm->minmax_acctotal+=LIMITBITS(stackctr,limit);
515 if(stackctr<bm->minmax_stackptr)
516 for(i=0;i<bins*2;i++)
517 bm->minmax_binstack[stackctr*bins*2+i]+=
518 bm->minmax_binstack[(stackctr+1)*bins*2+i];
523 bm->minmax_posstack[stackctr]=bm->minmax_posstack[bm->minmax_stackptr];
524 bm->minmax_limitstack[stackctr]=limit;
526 /* set up new blank stack entry */
528 bm->minmax_stackptr=stackctr;
529 memset(&bm->minmax_binstack[stackctr*bins*2],
531 sizeof(*bm->minmax_binstack)*bins*2);
532 bm->minmax_limitstack[stackctr]=0;
533 bm->minmax_posstack[stackctr]=-1;
538 /* remove from tail */
539 while(bm->minmax_sampleacc>sampledesired){
541 ci->blocksizes[bm->queue_actual[bm->minmax_tail]&0x80000000UL?1:0]>>1;
542 int actual=bm->queue_actual[bm->minmax_tail]&0x7fffffffUL;
545 bm->minmax_binstack[bins+i]-= /* always comes off the stack bottom */
546 LACING_ADJUST(BINBITS(bm,bm->minmax_tail,
547 actual>((i+1)<<BITTRACK_BPT)?
548 actual:((i+1)<<BITTRACK_BPT)));
549 bm->minmax_binstack[i]-=
550 LACING_ADJUST(BINBITS(bm,bm->minmax_tail,
551 actual<((i+1)<<BITTRACK_BPT)?
552 actual:((i+1)<<BITTRACK_BPT)));
555 /* always perform in this order; max overrules min */
556 if((bm->minmax_limitstack[0]<<BITTRACK_BPT)>actual)
557 actual=(bm->minmax_limitstack[0]<<BITTRACK_BPT);
558 if(((bins+bm->minmax_limitstack[0])<<BITTRACK_BPT)<actual)
559 actual=(bins+bm->minmax_limitstack[0])<<BITTRACK_BPT;
561 bm->minmax_acctotal-=LACING_ADJUST(BINBITS(bm,bm->minmax_tail,actual));
562 bm->minmax_sampleacc-=samples;
564 /* revise queue_actual to reflect the limit */
565 bm->queue_actual[bm->minmax_tail]&=0x80000000UL;
566 bm->queue_actual[bm->minmax_tail]|=actual;
568 if(bm->minmax_tail==bm->minmax_posstack[0]){
569 /* the stack becomes a FIFO; the first data has fallen off */
570 memmove(bm->minmax_binstack,bm->minmax_binstack+bins*2,
571 sizeof(*bm->minmax_binstack)*bins*2*bm->minmax_stackptr);
572 memmove(bm->minmax_posstack,bm->minmax_posstack+1,
573 sizeof(*bm->minmax_posstack)*bm->minmax_stackptr);
574 memmove(bm->minmax_limitstack,bm->minmax_limitstack+1,
575 sizeof(*bm->minmax_limitstack)*bm->minmax_stackptr);
576 bm->minmax_stackptr--;
580 if(bm->minmax_tail>=bm->queue_size)bm->minmax_tail=0;
584 bm->last_to_flush=bm->minmax_tail;
586 bm->last_to_flush=bm->avg_center;
589 bm->last_to_flush=bm->queue_head;
593 int vorbis_bitrate_flushpacket(vorbis_dsp_state *vd,ogg_packet *op){
594 backend_lookup_state *b=vd->backend_state;
595 bitrate_manager_state *bm=&b->bms;
597 if(bm->queue_size==0){
598 if(bm->queue_head==0)return(0);
600 memcpy(op,bm->queue_packets,sizeof(*op));
607 if(bm->next_to_flush==bm->last_to_flush)return(0);
609 bin=bm->queue_actual[bm->next_to_flush];
610 bytes=(BINBITS(bm,bm->next_to_flush,bin)+7)/8;
612 memcpy(op,bm->queue_packets+bm->next_to_flush,sizeof(*op));
614 if(bytes<op->bytes)op->bytes=bytes;
617 if(bm->next_to_flush>=bm->queue_size)bm->next_to_flush=0;