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 1994-2001 *
9 * by the XIPHOPHORUS Company http://www.xiph.org/ *
11 ********************************************************************
13 function: bitrate tracking and management
14 last mod: $Id: bitrate.c,v 1.3 2001/12/14 07:21:16 xiphmont Exp $
16 ********************************************************************/
24 #include "vorbis/codec.h"
25 #include "codec_internal.h"
29 #define BINBITS(pos,bin) ((bin)>0?bm->queue_binned[(pos)*bins+(bin)-1]:0)
30 #define LIMITBITS(pos,bin) ((bin)>-bins?\
31 bm->minmax_binstack[(pos)*bins*2+((bin)+bins)-1]:0)
33 static long LACING_ADJUST(long bits){
34 int addto=((bits+7)/8+1)/256+1;
35 return( ((bits+7)/8+addto)*8 );
38 static double floater_interpolate(bitrate_manager_state *bm,vorbis_info *vi,
40 int bin=bm->avgfloat*BITTRACK_DIVISOR-1.;
44 lobitrate=(double)(bin==0?0:bm->avg_binacc[bin-1])/bm->avg_sampleacc*vi->rate;
45 while(lobitrate>desired_rate && bin>0){
47 lobitrate=(double)(bin==0?0:bm->avg_binacc[bin-1])/bm->avg_sampleacc*vi->rate;
50 hibitrate=(double)(bin>=bm->queue_bins?bm->avg_binacc[bm->queue_bins-1]:
51 bm->avg_binacc[bin])/bm->avg_sampleacc*vi->rate;
52 while(hibitrate<desired_rate && bin<bm->queue_bins){
54 if(bin<bm->queue_bins)
55 hibitrate=(double)bm->avg_binacc[bin]/bm->avg_sampleacc*vi->rate;
59 if(bin==bm->queue_bins){
60 return bin/(double)BITTRACK_DIVISOR;
62 double delta=(desired_rate-lobitrate)/(hibitrate-lobitrate);
63 return (bin+delta)/(double)BITTRACK_DIVISOR;
67 /* try out a new limit */
68 static long limit_sum(bitrate_manager_state *bm,int limit){
69 int i=bm->minmax_stackptr;
70 long acc=bm->minmax_acctotal;
71 long bins=bm->queue_bins;
74 acc+=LIMITBITS(i,limit);
77 if(bm->minmax_limitstack[i]<=limit)break;
78 acc-=LIMITBITS(i,bm->minmax_limitstack[i]);
79 acc+=LIMITBITS(i,limit);
84 /* compute bitrate tracking setup, allocate circular packet size queue */
85 void vorbis_bitrate_init(vorbis_info *vi,bitrate_manager_state *bm){
87 codec_setup_info *ci=vi->codec_setup;
88 bitrate_manager_info *bi=&ci->bi;
91 memset(bm,0,sizeof(*bm));
95 bm->avg_sampledesired=bi->queue_avg_time*vi->rate;
96 bm->avg_centerdesired=bi->queue_avg_time*vi->rate*bi->queue_avg_center;
97 bm->minmax_sampledesired=bi->queue_minmax_time*vi->rate;
99 /* first find the max possible needed queue size */
100 maxlatency=max(bm->avg_sampledesired-bm->avg_centerdesired,
101 bm->minmax_sampledesired)+bm->avg_centerdesired;
104 (bi->queue_avgmin>0 || bi->queue_avgmax>0 || bi->queue_hardmax>0 ||
105 bi->queue_hardmin>0)){
106 long maxpackets=maxlatency/(ci->blocksizes[0]>>1)+3;
107 long bins=BITTRACK_DIVISOR*ci->passlimit[ci->coupling_passes-1];
109 bm->queue_size=maxpackets;
111 bm->queue_binned=_ogg_malloc(maxpackets*bins*sizeof(*bm->queue_binned));
112 bm->queue_actual=_ogg_malloc(maxpackets*sizeof(*bm->queue_actual));
114 if((bi->queue_avgmin>0 || bi->queue_avgmax>0) &&
115 bi->queue_avg_time>0){
117 bm->avg_binacc=_ogg_malloc(bins*sizeof(*bm->avg_binacc));
118 bm->avgfloat=bi->avgfloat_initial;
125 if((bi->queue_hardmin>0 || bi->queue_hardmax>0) &&
126 bi->queue_minmax_time>0){
128 bm->minmax_binstack=_ogg_malloc((bins+1)*bins*2*
129 sizeof(bm->minmax_binstack));
130 bm->minmax_posstack=_ogg_malloc((bins+1)*
131 sizeof(bm->minmax_posstack));
132 bm->minmax_limitstack=_ogg_malloc((bins+1)*
133 sizeof(bm->minmax_limitstack));
138 /* space for the packet queueing */
139 bm->queue_packet_buffers=calloc(maxpackets,sizeof(*bm->queue_packet_buffers));
140 bm->queue_packets=calloc(maxpackets,sizeof(*bm->queue_packets));
141 for(i=0;i<maxpackets;i++)
142 oggpack_writeinit(bm->queue_packet_buffers+i);
145 bm->queue_packet_buffers=calloc(1,sizeof(*bm->queue_packet_buffers));
146 bm->queue_packets=calloc(1,sizeof(*bm->queue_packets));
147 oggpack_writeinit(bm->queue_packet_buffers);
152 void vorbis_bitrate_clear(bitrate_manager_state *bm){
155 if(bm->queue_binned)_ogg_free(bm->queue_binned);
156 if(bm->queue_actual)_ogg_free(bm->queue_actual);
157 if(bm->avg_binacc)_ogg_free(bm->avg_binacc);
158 if(bm->minmax_binstack)_ogg_free(bm->minmax_binstack);
159 if(bm->minmax_posstack)_ogg_free(bm->minmax_posstack);
160 if(bm->minmax_limitstack)_ogg_free(bm->minmax_limitstack);
161 if(bm->queue_packet_buffers){
162 if(bm->queue_size==0){
163 oggpack_writeclear(bm->queue_packet_buffers);
164 _ogg_free(bm->queue_packet_buffers);
166 for(i=0;i<bm->queue_size;i++)
167 oggpack_writeclear(bm->queue_packet_buffers+i);
168 _ogg_free(bm->queue_packet_buffers);
171 if(bm->queue_packets)_ogg_free(bm->queue_packets);
172 memset(bm,0,sizeof(*bm));
176 int vorbis_bitrate_managed(vorbis_block *vb){
177 vorbis_dsp_state *vd=vb->vd;
178 backend_lookup_state *b=vd->backend_state;
179 bitrate_manager_state *bm=&b->bms;
181 if(bm->queue_binned)return(1);
185 int vorbis_bitrate_maxmarkers(void){
186 return 8*BITTRACK_DIVISOR;
189 /* finish taking in the block we just processed */
190 int vorbis_bitrate_addblock(vorbis_block *vb){
192 vorbis_block_internal *vbi=vb->internal;
193 vorbis_dsp_state *vd=vb->vd;
194 backend_lookup_state *b=vd->backend_state;
195 bitrate_manager_state *bm=&b->bms;
196 vorbis_info *vi=vd->vi;
197 codec_setup_info *ci=vi->codec_setup;
198 bitrate_manager_info *bi=&ci->bi;
199 int eofflag=vb->eofflag;
200 int head=bm->queue_head;
201 int next_head=head+1;
202 int bins=bm->queue_bins;
203 int minmax_head,new_minmax_head;
205 ogg_uint32_t *head_ptr;
208 if(!bm->queue_binned){
210 /* not a bitrate managed stream, but for API simplicity, we'll
211 buffer one packet to keep the code path clean */
213 if(bm->queue_head)return(-1); /* one has been submitted without
217 bm->queue_packets[0].packet=oggpack_get_buffer(&vb->opb);
218 bm->queue_packets[0].bytes=oggpack_bytes(&vb->opb);
219 bm->queue_packets[0].b_o_s=0;
220 bm->queue_packets[0].e_o_s=vb->eofflag;
221 bm->queue_packets[0].granulepos=vb->granulepos;
222 bm->queue_packets[0].packetno=vb->sequence; /* for sake of completeness */
224 memcpy(&temp,bm->queue_packet_buffers,sizeof(vb->opb));
225 memcpy(bm->queue_packet_buffers,&vb->opb,sizeof(vb->opb));
226 memcpy(&vb->opb,&temp,sizeof(vb->opb));
231 /* add encoded packet to head */
232 if(next_head>=bm->queue_size)next_head=0;
233 head_ptr=bm->queue_binned+bins*head;
235 /* is there room to add a block? In proper use of the API, this will
236 never come up... but guard it anyway */
237 if(next_head==bm->avg_tail || next_head==bm->minmax_tail)return(-1);
239 /* add the block to the toplevel queue */
240 bm->queue_head=next_head;
241 bm->queue_actual[head]=(vb->W?0x80000000UL:0);
243 /* buffer packet fields */
244 bm->queue_packets[head].packet=oggpack_get_buffer(&vb->opb);
245 bm->queue_packets[head].bytes=oggpack_bytes(&vb->opb);
246 bm->queue_packets[head].b_o_s=0;
247 bm->queue_packets[head].e_o_s=vb->eofflag;
248 bm->queue_packets[head].granulepos=vb->granulepos;
249 bm->queue_packets[head].packetno=vb->sequence; /* for sake of completeness */
251 /* swap packet buffers */
252 memcpy(&temp,bm->queue_packet_buffers+head,sizeof(vb->opb));
253 memcpy(bm->queue_packet_buffers+head,&vb->opb,sizeof(vb->opb));
254 memcpy(&vb->opb,&temp,sizeof(vb->opb));
257 memcpy(head_ptr,vbi->packet_markers,sizeof(*head_ptr)*bins);
260 new_minmax_head=minmax_head=bm->avg_center;
262 new_minmax_head=minmax_head=head;
264 /* the average tracking queue is updated first; its results (if it's
265 in use) are taken into account by the min/max limiter (if min/max
268 long desired_center=bm->avg_centerdesired;
269 if(eofflag)desired_center=0;
271 /* update the avg head */
273 bm->avg_binacc[i]+=LACING_ADJUST(head_ptr[i]);
274 bm->avg_sampleacc+=ci->blocksizes[vb->W]>>1;
275 bm->avg_centeracc+=ci->blocksizes[vb->W]>>1;
277 /* update the avg tail if needed */
278 while(bm->avg_sampleacc>bm->avg_sampledesired){
280 ci->blocksizes[bm->queue_actual[bm->avg_tail]&0x80000000UL?1:0]>>1;
281 for(i=0;i<bm->queue_bins;i++)
282 bm->avg_binacc[i]-=LACING_ADJUST(bm->queue_binned[bins*bm->avg_tail+i]);
283 bm->avg_sampleacc-=samples;
285 if(bm->avg_tail>=bm->queue_size)bm->avg_tail=0;
288 /* update the avg center */
289 if(bm->avg_centeracc>desired_center){
290 /* choose the new average floater */
291 double upper=floater_interpolate(bm,vi,bi->queue_avgmax);
292 double lower=floater_interpolate(bm,vi,bi->queue_avgmin);
293 double new=bi->avgfloat_initial,slew;
296 if(upper>0. && upper<new)new=upper;
297 if(lower<bi->avgfloat_minimum)
298 lower=bi->avgfloat_minimum;
299 if(lower>new)new=lower;
301 slew=new-bm->avgfloat;
303 if(slew<bi->avgfloat_downhyst || slew>bi->avgfloat_uphyst){
304 if(slew<bi->avgfloat_downslew_max)
305 new=bm->avgfloat+bi->avgfloat_downslew_max;
306 if(slew>bi->avgfloat_upslew_max)
307 new=bm->avgfloat+bi->avgfloat_upslew_max;
312 /* apply the average floater to new blocks */
313 bin=bm->avgfloat*BITTRACK_DIVISOR; /* truncate on purpose */
314 fprintf(stderr,"float:%d ",bin);
315 while(bm->avg_centeracc>desired_center){
317 samples=ci->blocksizes[bm->queue_actual[bm->avg_center]&
318 0x80000000UL?1:0]>>1;
320 bm->queue_actual[bm->avg_center]|=bin;
322 bm->avg_centeracc-=samples;
324 if(bm->noisetrigger_postpone)bm->noisetrigger_postpone-=samples;
325 if(bm->avg_center>=bm->queue_size)bm->avg_center=0;
327 new_minmax_head=bm->avg_center;
329 /* track noise bias triggers and noise bias */
330 if(bm->avgfloat<bi->avgfloat_noise_lowtrigger)
331 bm->noisetrigger_request+=1.f;
333 if(bm->avgfloat>bi->avgfloat_noise_hightrigger)
334 bm->noisetrigger_request-=1.f;
336 if(bm->noisetrigger_postpone<=0){
337 if(bm->noisetrigger_request<0.){
339 if(bm->noisetrigger_request<bm->avg_sampleacc/2)
341 bm->noisetrigger_postpone=bm->avg_sampleacc/2;
343 if(bm->noisetrigger_request>0.){
345 if(bm->noisetrigger_request>bm->avg_sampleacc/2)
347 bm->noisetrigger_postpone=bm->avg_sampleacc/2;
350 /* we generally want the noise bias to drift back to zero */
351 bm->noisetrigger_request=0.f;
353 bm->noisetrigger_request= -1.;
355 bm->noisetrigger_request= +1.;
357 if(bm->avgnoise<bi->avgfloat_noise_minval)
358 bm->avgnoise=bi->avgfloat_noise_minval;
359 if(bm->avgnoise>bi->avgfloat_noise_maxval)
360 bm->avgnoise=bi->avgfloat_noise_maxval;
362 fprintf(stderr,"noise:%f req:%ld trigger:%ld\n",bm->avgnoise,
363 bm->noisetrigger_request,bm->noisetrigger_postpone);
367 /* if we're not using an average tracker, the 'float' is nailed to
368 the avgfloat_initial value. It needs to be set for the min/max
370 long bin=bi->avgfloat_initial*BITTRACK_DIVISOR; /* truncate on purpose */
371 bm->queue_actual[head]|=bin;
372 new_minmax_head=next_head;
375 /* update the min/max queues and enforce limits */
376 if(bm->minmax_binstack){
377 long sampledesired=eofflag?0:bm->minmax_sampledesired;
379 /* add to stack recent */
380 while(minmax_head!=new_minmax_head){
381 int samples=ci->blocksizes[bm->queue_actual[minmax_head]&
382 0x80000000UL?1:0]>>1;
384 /* the construction here is not parallel to the floater's
387 floater[bin-1] <-> floater supported at bin
389 floater[0] <-> floater supported at 1
390 supported at zero is implicit.
391 the BINBITS macro performs offsetting
394 bin minmax[bin*2-1] <-> floater supported at bin
396 1 minmax[bin] <-> floater supported at 1
397 0 minmax[bin-1] <-> no limit/support (limited to/supported at bin 0,
399 -1 minmax[bin-2] <-> floater limited to bin-1
401 -bin+1 minmax[0] <-> floater limited to 1
402 limited to zero (val= -bin) is implicit
405 bm->minmax_binstack[bm->minmax_stackptr*bins*2+bins+i]+=
408 (bm->queue_actual[minmax_head]&0x7fffffffUL)>i+1?
409 (bm->queue_actual[minmax_head]&0x7fffffffUL):i+1));
411 bm->minmax_binstack[bm->minmax_stackptr*bins*2+i]+=
414 (bm->queue_actual[minmax_head]&0x7fffffffUL)<i+1?
415 (bm->queue_actual[minmax_head]&0x7fffffffUL):i+1));
418 bm->minmax_posstack[bm->minmax_stackptr]=minmax_head; /* not one
422 bm->minmax_limitstack[bm->minmax_stackptr]=0;
423 bm->minmax_sampleacc+=samples;
424 bm->minmax_acctotal+=
426 BINBITS(minmax_head,(bm->queue_actual[minmax_head]&0x7fffffffUL)));
429 if(minmax_head>=bm->queue_size)minmax_head=0;
432 /* check limits, enforce changes */
433 if(bm->minmax_sampleacc>sampledesired){
434 double bitrate=(double)bm->minmax_acctotal/bm->minmax_sampleacc*vi->rate;
437 fprintf(stderr,"prelimit:%dkbps ",(int)bitrate/1000);
438 if(bitrate>bi->queue_hardmax || bitrate<bi->queue_hardmin){
441 long bitsum=limit_sum(bm,0);
442 bitrate=(double)bitsum/bm->minmax_sampleacc*vi->rate;
444 /* we're off rate. Iteratively try out new hard floater
445 limits until we find one that brings us inside. Here's
446 where we see the whole point of the limit stacks. */
447 if(bitrate>bi->queue_hardmax){
448 for(limit=-1;limit>-bins;limit--){
449 long bitsum=limit_sum(bm,limit);
450 bitrate=(double)bitsum/bm->minmax_sampleacc*vi->rate;
451 if(bitrate<=bi->queue_hardmax)break;
453 }else if(bitrate<bi->queue_hardmin){
454 for(limit=1;limit<bins;limit++){
455 long bitsum=limit_sum(bm,limit);
456 bitrate=(double)bitsum/bm->minmax_sampleacc*vi->rate;
457 if(bitrate>=bi->queue_hardmin)break;
459 if(bitrate>bi->queue_hardmax)limit--;
462 bitsum=limit_sum(bm,limit);
463 bitrate=(double)bitsum/bm->minmax_sampleacc*vi->rate;
464 fprintf(stderr,"postlimit:%dkbps ",(int)bitrate/1000);
466 /* trace the limit backward, stop when we see a lower limit */
467 newstack=bm->minmax_stackptr-1;
469 if(bm->minmax_limitstack[newstack]<limit)break;
473 /* update bit counter with new limit and replace any stack
474 limits that have been replaced by our new lower limit */
475 stackctr=bm->minmax_stackptr;
476 while(stackctr>newstack){
477 bm->minmax_acctotal-=
478 LIMITBITS(stackctr,bm->minmax_limitstack[stackctr]);
479 bm->minmax_acctotal+=LIMITBITS(stackctr,limit);
481 if(stackctr<bm->minmax_stackptr)
482 for(i=0;i<bins*2;i++)
483 bm->minmax_binstack[stackctr*bins*2+i]+=
484 bm->minmax_binstack[(stackctr+1)*bins*2+i];
489 bm->minmax_posstack[stackctr]=bm->minmax_posstack[bm->minmax_stackptr];
490 bm->minmax_limitstack[stackctr]=limit;
491 fprintf(stderr,"limit:%d\n",limit);
493 /* set up new blank stack entry */
495 bm->minmax_stackptr=stackctr;
496 memset(&bm->minmax_binstack[stackctr*bins*2],
498 sizeof(*bm->minmax_binstack)*bins*2);
499 bm->minmax_limitstack[stackctr]=0;
500 bm->minmax_posstack[stackctr]=-1;
505 /* remove from tail */
506 while(bm->minmax_sampleacc>sampledesired){
508 ci->blocksizes[bm->queue_actual[bm->minmax_tail]&0x80000000UL?1:0]>>1;
509 int actual=bm->queue_actual[bm->minmax_tail]&0x7fffffffUL;
512 bm->minmax_binstack[bins+i]-= /* always comes off the stack bottom */
513 LACING_ADJUST(BINBITS(bm->minmax_tail,actual>i+1?actual:i+1));
514 bm->minmax_binstack[i]-=
515 LACING_ADJUST(BINBITS(bm->minmax_tail,actual<i+1?actual:i+1));
518 /* always perform in this order; max overrules min */
519 if(bm->minmax_limitstack[0]>actual)
520 actual=bm->minmax_limitstack[0];
521 if(bins+bm->minmax_limitstack[0]<actual)
522 actual=bins+bm->minmax_limitstack[0];
524 bm->minmax_acctotal-=LACING_ADJUST(BINBITS(bm->minmax_tail,actual));
525 bm->minmax_sampleacc-=samples;
527 /* revise queue_actual to reflect the limit */
528 bm->queue_actual[bm->minmax_tail]=actual;
530 if(bm->minmax_tail==bm->minmax_posstack[0]){
531 /* the stack becomes a FIFO; the first data has fallen off */
532 memmove(bm->minmax_binstack,bm->minmax_binstack+bins*2,
533 sizeof(*bm->minmax_binstack)*bins*2*bm->minmax_stackptr);
534 memmove(bm->minmax_posstack,bm->minmax_posstack+1,
535 sizeof(*bm->minmax_posstack)*bm->minmax_stackptr);
536 memmove(bm->minmax_limitstack,bm->minmax_limitstack+1,
537 sizeof(*bm->minmax_limitstack)*bm->minmax_stackptr);
538 bm->minmax_stackptr--;
542 if(bm->minmax_tail>=bm->queue_size)bm->minmax_tail=0;
546 bm->last_to_flush=bm->minmax_tail;
548 bm->last_to_flush=bm->avg_center;
551 bm->last_to_flush=bm->queue_head;
555 int vorbis_bitrate_flushpacket(vorbis_dsp_state *vd,ogg_packet *op){
556 backend_lookup_state *b=vd->backend_state;
557 bitrate_manager_state *bm=&b->bms;
559 if(bm->queue_size==0){
560 if(bm->queue_head==0)return(0);
562 memcpy(op,bm->queue_packets,sizeof(*op));
566 long bins=bm->queue_bins;
570 if(bm->next_to_flush==bm->last_to_flush)return(0);
572 bin=bm->queue_actual[bm->next_to_flush]&0x7fffffffUL;
573 bytes=(BINBITS(bm->next_to_flush,bin)+7)/8;
575 memcpy(op,bm->queue_packets+bm->next_to_flush,sizeof(*op));
576 if(bytes<op->bytes)op->bytes=bytes;
579 if(bm->next_to_flush>=bm->queue_size)bm->next_to_flush=0;