2 * Rate control for video encoders
4 * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
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.
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.
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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 * Rate control for video encoders.
28 #include "mpegvideo.h"
30 #undef NDEBUG // allways check asserts, the speed effect is far too small to disable them
34 #define M_E 2.718281828
37 static int init_pass2(MpegEncContext *s);
38 static double get_qscale(MpegEncContext *s, RateControlEntry *rce, double rate_factor, int frame_num);
40 void ff_write_pass1_stats(MpegEncContext *s){
41 sprintf(s->avctx->stats_out, "in:%d out:%d type:%d q:%d itex:%d ptex:%d mv:%d misc:%d fcode:%d bcode:%d mc-var:%d var:%d icount:%d;\n",
42 s->current_picture_ptr->display_picture_number, s->current_picture_ptr->coded_picture_number, s->pict_type,
43 s->current_picture.quality, s->i_tex_bits, s->p_tex_bits, s->mv_bits, s->misc_bits,
44 s->f_code, s->b_code, s->current_picture.mc_mb_var_sum, s->current_picture.mb_var_sum, s->i_count);
47 int ff_rate_control_init(MpegEncContext *s)
49 RateControlContext *rcc= &s->rc_context;
54 rcc->pred[i].coeff= FF_QP2LAMBDA * 7.0;
55 rcc->pred[i].count= 1.0;
57 rcc->pred[i].decay= 0.4;
62 rcc->frame_count[i]= 1; // 1 is better cuz of 1/0 and such
63 rcc->last_qscale_for[i]=FF_QP2LAMBDA * 5;
65 rcc->buffer_index= s->avctx->rc_initial_buffer_occupancy;
67 if(s->flags&CODEC_FLAG_PASS2){
71 /* find number of pics */
72 p= s->avctx->stats_in;
77 rcc->entry = (RateControlEntry*)av_mallocz(i*sizeof(RateControlEntry));
80 /* init all to skiped p frames (with b frames we might have a not encoded frame at the end FIXME) */
81 for(i=0; i<rcc->num_entries; i++){
82 RateControlEntry *rce= &rcc->entry[i];
83 rce->pict_type= rce->new_pict_type=P_TYPE;
84 rce->qscale= rce->new_qscale=FF_QP2LAMBDA * 2;
85 rce->misc_bits= s->mb_num + 10;
86 rce->mb_var_sum= s->mb_num*100;
90 p= s->avctx->stats_in;
91 for(i=0; i<rcc->num_entries - s->max_b_frames; i++){
92 RateControlEntry *rce;
99 (*next)=0; //sscanf in unbelieavle slow on looong strings //FIXME copy / dont write
102 e= sscanf(p, " in:%d ", &picture_number);
104 assert(picture_number >= 0);
105 assert(picture_number < rcc->num_entries);
106 rce= &rcc->entry[picture_number];
108 e+=sscanf(p, " in:%*d out:%*d type:%d q:%f itex:%d ptex:%d mv:%d misc:%d fcode:%d bcode:%d mc-var:%d var:%d icount:%d",
109 &rce->pict_type, &rce->qscale, &rce->i_tex_bits, &rce->p_tex_bits, &rce->mv_bits, &rce->misc_bits,
110 &rce->f_code, &rce->b_code, &rce->mc_mb_var_sum, &rce->mb_var_sum, &rce->i_count);
112 av_log(s->avctx, AV_LOG_ERROR, "statistics are damaged at line %d, parser out=%d\n", i, e);
118 if(init_pass2(s) < 0) return -1;
121 if(!(s->flags&CODEC_FLAG_PASS2)){
123 rcc->short_term_qsum=0.001;
124 rcc->short_term_qcount=0.001;
126 rcc->pass1_rc_eq_output_sum= 0.001;
127 rcc->pass1_wanted_bits=0.001;
129 /* init stuff with the user specified complexity */
130 if(s->avctx->rc_initial_cplx){
131 for(i=0; i<60*30; i++){
132 double bits= s->avctx->rc_initial_cplx * (i/10000.0 + 1.0)*s->mb_num;
133 RateControlEntry rce;
136 if (i%((s->gop_size+3)/4)==0) rce.pict_type= I_TYPE;
137 else if(i%(s->max_b_frames+1)) rce.pict_type= B_TYPE;
138 else rce.pict_type= P_TYPE;
140 rce.new_pict_type= rce.pict_type;
141 rce.mc_mb_var_sum= bits*s->mb_num/100000;
142 rce.mb_var_sum = s->mb_num;
143 rce.qscale = FF_QP2LAMBDA * 2;
148 if(s->pict_type== I_TYPE){
149 rce.i_count = s->mb_num;
150 rce.i_tex_bits= bits;
154 rce.i_count = 0; //FIXME we do know this approx
156 rce.p_tex_bits= bits*0.9;
157 rce.mv_bits= bits*0.1;
159 rcc->i_cplx_sum [rce.pict_type] += rce.i_tex_bits*rce.qscale;
160 rcc->p_cplx_sum [rce.pict_type] += rce.p_tex_bits*rce.qscale;
161 rcc->mv_bits_sum[rce.pict_type] += rce.mv_bits;
162 rcc->frame_count[rce.pict_type] ++;
164 bits= rce.i_tex_bits + rce.p_tex_bits;
166 q= get_qscale(s, &rce, rcc->pass1_wanted_bits/rcc->pass1_rc_eq_output_sum, i);
167 rcc->pass1_wanted_bits+= s->bit_rate/(s->avctx->frame_rate / (double)s->avctx->frame_rate_base);
176 void ff_rate_control_uninit(MpegEncContext *s)
178 RateControlContext *rcc= &s->rc_context;
181 av_freep(&rcc->entry);
184 static inline double qp2bits(RateControlEntry *rce, double qp){
186 av_log(NULL, AV_LOG_ERROR, "qp<=0.0\n");
188 return rce->qscale * (double)(rce->i_tex_bits + rce->p_tex_bits+1)/ qp;
191 static inline double bits2qp(RateControlEntry *rce, double bits){
193 av_log(NULL, AV_LOG_ERROR, "bits<0.9\n");
195 return rce->qscale * (double)(rce->i_tex_bits + rce->p_tex_bits+1)/ bits;
198 int ff_vbv_update(MpegEncContext *s, int frame_size){
199 RateControlContext *rcc= &s->rc_context;
200 const double fps= (double)s->avctx->frame_rate / (double)s->avctx->frame_rate_base;
201 const int buffer_size= s->avctx->rc_buffer_size;
202 const double min_rate= s->avctx->rc_min_rate/fps;
203 const double max_rate= s->avctx->rc_max_rate/fps;
205 //printf("%d %f %d %f %f\n", buffer_size, rcc->buffer_index, frame_size, min_rate, max_rate);
209 rcc->buffer_index-= frame_size;
210 if(rcc->buffer_index < 0){
211 av_log(s->avctx, AV_LOG_ERROR, "rc buffer underflow\n");
212 rcc->buffer_index= 0;
215 left= buffer_size - rcc->buffer_index - 1;
216 rcc->buffer_index += clip(left, min_rate, max_rate);
218 if(rcc->buffer_index > buffer_size){
219 int stuffing= ceil((rcc->buffer_index - buffer_size)/8);
221 if(stuffing < 4 && s->codec_id == CODEC_ID_MPEG4)
223 rcc->buffer_index -= 8*stuffing;
225 if(s->avctx->debug & FF_DEBUG_RC)
226 av_log(s->avctx, AV_LOG_DEBUG, "stuffing %d bytes\n", stuffing);
235 * modifies the bitrate curve from pass1 for one frame
237 static double get_qscale(MpegEncContext *s, RateControlEntry *rce, double rate_factor, int frame_num){
238 RateControlContext *rcc= &s->rc_context;
239 AVCodecContext *a= s->avctx;
241 const int pict_type= rce->new_pict_type;
242 const double mb_num= s->mb_num;
245 double const_values[]={
248 rce->i_tex_bits*rce->qscale,
249 rce->p_tex_bits*rce->qscale,
250 (rce->i_tex_bits + rce->p_tex_bits)*(double)rce->qscale,
252 rce->pict_type == B_TYPE ? (rce->f_code + rce->b_code)*0.5 : rce->f_code,
254 rce->mc_mb_var_sum/mb_num,
255 rce->mb_var_sum/mb_num,
256 rce->pict_type == I_TYPE,
257 rce->pict_type == P_TYPE,
258 rce->pict_type == B_TYPE,
259 rcc->qscale_sum[pict_type] / (double)rcc->frame_count[pict_type],
261 /* rcc->last_qscale_for[I_TYPE],
262 rcc->last_qscale_for[P_TYPE],
263 rcc->last_qscale_for[B_TYPE],
264 rcc->next_non_b_qscale,*/
265 rcc->i_cplx_sum[I_TYPE] / (double)rcc->frame_count[I_TYPE],
266 rcc->i_cplx_sum[P_TYPE] / (double)rcc->frame_count[P_TYPE],
267 rcc->p_cplx_sum[P_TYPE] / (double)rcc->frame_count[P_TYPE],
268 rcc->p_cplx_sum[B_TYPE] / (double)rcc->frame_count[B_TYPE],
269 (rcc->i_cplx_sum[pict_type] + rcc->p_cplx_sum[pict_type]) / (double)rcc->frame_count[pict_type],
272 static const char *const_names[]={
299 static double (*func1[])(void *, double)={
304 static const char *func1_names[]={
310 bits= ff_eval(s->avctx->rc_eq, const_values, const_names, func1, func1_names, NULL, NULL, rce);
312 rcc->pass1_rc_eq_output_sum+= bits;
314 if(bits<0.0) bits=0.0;
315 bits+= 1.0; //avoid 1/0 issues
318 for(i=0; i<s->avctx->rc_override_count; i++){
319 RcOverride *rco= s->avctx->rc_override;
320 if(rco[i].start_frame > frame_num) continue;
321 if(rco[i].end_frame < frame_num) continue;
324 bits= qp2bits(rce, rco[i].qscale); //FIXME move at end to really force it?
326 bits*= rco[i].quality_factor;
329 q= bits2qp(rce, bits);
332 if (pict_type==I_TYPE && s->avctx->i_quant_factor<0.0)
333 q= -q*s->avctx->i_quant_factor + s->avctx->i_quant_offset;
334 else if(pict_type==B_TYPE && s->avctx->b_quant_factor<0.0)
335 q= -q*s->avctx->b_quant_factor + s->avctx->b_quant_offset;
340 static double get_diff_limited_q(MpegEncContext *s, RateControlEntry *rce, double q){
341 RateControlContext *rcc= &s->rc_context;
342 AVCodecContext *a= s->avctx;
343 const int pict_type= rce->new_pict_type;
344 const double last_p_q = rcc->last_qscale_for[P_TYPE];
345 const double last_non_b_q= rcc->last_qscale_for[rcc->last_non_b_pict_type];
347 if (pict_type==I_TYPE && (a->i_quant_factor>0.0 || rcc->last_non_b_pict_type==P_TYPE))
348 q= last_p_q *ABS(a->i_quant_factor) + a->i_quant_offset;
349 else if(pict_type==B_TYPE && a->b_quant_factor>0.0)
350 q= last_non_b_q* a->b_quant_factor + a->b_quant_offset;
352 /* last qscale / qdiff stuff */
353 if(rcc->last_non_b_pict_type==pict_type || pict_type!=I_TYPE){
354 double last_q= rcc->last_qscale_for[pict_type];
355 const int maxdiff= FF_QP2LAMBDA * a->max_qdiff;
357 if (q > last_q + maxdiff) q= last_q + maxdiff;
358 else if(q < last_q - maxdiff) q= last_q - maxdiff;
361 rcc->last_qscale_for[pict_type]= q; //Note we cant do that after blurring
363 if(pict_type!=B_TYPE)
364 rcc->last_non_b_pict_type= pict_type;
370 * gets the qmin & qmax for pict_type
372 static void get_qminmax(int *qmin_ret, int *qmax_ret, MpegEncContext *s, int pict_type){
373 int qmin= s->avctx->lmin;
374 int qmax= s->avctx->lmax;
376 assert(qmin <= qmax);
378 if(pict_type==B_TYPE){
379 qmin= (int)(qmin*ABS(s->avctx->b_quant_factor)+s->avctx->b_quant_offset + 0.5);
380 qmax= (int)(qmax*ABS(s->avctx->b_quant_factor)+s->avctx->b_quant_offset + 0.5);
381 }else if(pict_type==I_TYPE){
382 qmin= (int)(qmin*ABS(s->avctx->i_quant_factor)+s->avctx->i_quant_offset + 0.5);
383 qmax= (int)(qmax*ABS(s->avctx->i_quant_factor)+s->avctx->i_quant_offset + 0.5);
386 qmin= clip(qmin, 1, FF_LAMBDA_MAX);
387 qmax= clip(qmax, 1, FF_LAMBDA_MAX);
389 if(qmax<qmin) qmax= qmin;
395 static double modify_qscale(MpegEncContext *s, RateControlEntry *rce, double q, int frame_num){
396 RateControlContext *rcc= &s->rc_context;
399 const int pict_type= rce->new_pict_type;
400 const double buffer_size= s->avctx->rc_buffer_size;
401 const double fps= (double)s->avctx->frame_rate / (double)s->avctx->frame_rate_base;
402 const double min_rate= s->avctx->rc_min_rate / fps;
403 const double max_rate= s->avctx->rc_max_rate / fps;
405 get_qminmax(&qmin, &qmax, s, pict_type);
408 if(s->avctx->rc_qmod_freq && frame_num%s->avctx->rc_qmod_freq==0 && pict_type==P_TYPE)
409 q*= s->avctx->rc_qmod_amp;
411 bits= qp2bits(rce, q);
412 //printf("q:%f\n", q);
413 /* buffer overflow/underflow protection */
415 double expected_size= rcc->buffer_index;
419 double d= 2*(buffer_size - expected_size)/buffer_size;
421 else if(d<0.0001) d=0.0001;
422 q*= pow(d, 1.0/s->avctx->rc_buffer_aggressivity);
424 q_limit= bits2qp(rce, FFMAX((min_rate - buffer_size + rcc->buffer_index)*3, 1));
426 if(s->avctx->debug&FF_DEBUG_RC){
427 av_log(s->avctx, AV_LOG_DEBUG, "limiting QP %f -> %f\n", q, q_limit);
434 double d= 2*expected_size/buffer_size;
436 else if(d<0.0001) d=0.0001;
437 q/= pow(d, 1.0/s->avctx->rc_buffer_aggressivity);
439 q_limit= bits2qp(rce, FFMAX(rcc->buffer_index/3, 1));
441 if(s->avctx->debug&FF_DEBUG_RC){
442 av_log(s->avctx, AV_LOG_DEBUG, "limiting QP %f -> %f\n", q, q_limit);
448 //printf("q:%f max:%f min:%f size:%f index:%d bits:%f agr:%f\n", q,max_rate, min_rate, buffer_size, rcc->buffer_index, bits, s->avctx->rc_buffer_aggressivity);
449 if(s->avctx->rc_qsquish==0.0 || qmin==qmax){
451 else if(q>qmax) q=qmax;
453 double min2= log(qmin);
454 double max2= log(qmax);
457 q= (q - min2)/(max2-min2) - 0.5;
459 q= 1.0/(1.0 + exp(q));
460 q= q*(max2-min2) + min2;
468 //----------------------------------
471 static double predict_size(Predictor *p, double q, double var)
473 return p->coeff*var / (q*p->count);
477 static double predict_qp(Predictor *p, double size, double var)
479 //printf("coeff:%f, count:%f, var:%f, size:%f//\n", p->coeff, p->count, var, size);
480 return p->coeff*var / (size*p->count);
484 static void update_predictor(Predictor *p, double q, double var, double size)
486 double new_coeff= size*q / (var + 1);
492 p->coeff+= new_coeff;
495 static void adaptive_quantization(MpegEncContext *s, double q){
497 const float lumi_masking= s->avctx->lumi_masking / (128.0*128.0);
498 const float dark_masking= s->avctx->dark_masking / (128.0*128.0);
499 const float temp_cplx_masking= s->avctx->temporal_cplx_masking;
500 const float spatial_cplx_masking = s->avctx->spatial_cplx_masking;
501 const float p_masking = s->avctx->p_masking;
504 float cplx_tab[s->mb_num];
505 float bits_tab[s->mb_num];
506 const int qmin= s->avctx->lmin;
507 const int qmax= s->avctx->lmax;
508 Picture * const pic= &s->current_picture;
510 for(i=0; i<s->mb_num; i++){
511 const int mb_xy= s->mb_index2xy[i];
512 float temp_cplx= sqrt(pic->mc_mb_var[mb_xy]); //FIXME merge in pow()
513 float spat_cplx= sqrt(pic->mb_var[mb_xy]);
514 const int lumi= pic->mb_mean[mb_xy];
515 float bits, cplx, factor;
517 if(spat_cplx < q/3) spat_cplx= q/3; //FIXME finetune
518 if(temp_cplx < q/3) temp_cplx= q/3; //FIXME finetune
520 if(spat_cplx < 4) spat_cplx= 4; //FIXME finetune
521 if(temp_cplx < 4) temp_cplx= 4; //FIXME finetune
523 if((s->mb_type[mb_xy]&CANDIDATE_MB_TYPE_INTRA)){//FIXME hq mode
525 factor= 1.0 + p_masking;
528 factor= pow(temp_cplx, - temp_cplx_masking);
530 factor*=pow(spat_cplx, - spatial_cplx_masking);
533 factor*= (1.0 - (lumi-128)*(lumi-128)*lumi_masking);
535 factor*= (1.0 - (lumi-128)*(lumi-128)*dark_masking);
537 if(factor<0.00001) factor= 0.00001;
546 /* handle qmin/qmax cliping */
547 if(s->flags&CODEC_FLAG_NORMALIZE_AQP){
548 float factor= bits_sum/cplx_sum;
549 for(i=0; i<s->mb_num; i++){
550 float newq= q*cplx_tab[i]/bits_tab[i];
554 bits_sum -= bits_tab[i];
555 cplx_sum -= cplx_tab[i]*q/qmax;
557 else if(newq < qmin){
558 bits_sum -= bits_tab[i];
559 cplx_sum -= cplx_tab[i]*q/qmin;
562 if(bits_sum < 0.001) bits_sum= 0.001;
563 if(cplx_sum < 0.001) cplx_sum= 0.001;
566 for(i=0; i<s->mb_num; i++){
567 const int mb_xy= s->mb_index2xy[i];
568 float newq= q*cplx_tab[i]/bits_tab[i];
571 if(s->flags&CODEC_FLAG_NORMALIZE_AQP){
572 newq*= bits_sum/cplx_sum;
575 intq= (int)(newq + 0.5);
577 if (intq > qmax) intq= qmax;
578 else if(intq < qmin) intq= qmin;
579 //if(i%s->mb_width==0) printf("\n");
580 //printf("%2d%3d ", intq, ff_sqrt(s->mc_mb_var[i]));
581 s->lambda_table[mb_xy]= intq;
584 //FIXME rd or at least approx for dquant
586 float ff_rate_estimate_qscale(MpegEncContext *s)
590 float br_compensation;
594 int picture_number= s->picture_number;
596 RateControlContext *rcc= &s->rc_context;
597 AVCodecContext *a= s->avctx;
598 RateControlEntry local_rce, *rce;
602 const int pict_type= s->pict_type;
603 Picture * const pic= &s->current_picture;
606 get_qminmax(&qmin, &qmax, s, pict_type);
608 fps= (double)s->avctx->frame_rate / (double)s->avctx->frame_rate_base;
609 //printf("input_pic_num:%d pic_num:%d frame_rate:%d\n", s->input_picture_number, s->picture_number, s->frame_rate);
610 /* update predictors */
611 if(picture_number>2){
612 const int last_var= s->last_pict_type == I_TYPE ? rcc->last_mb_var_sum : rcc->last_mc_mb_var_sum;
613 update_predictor(&rcc->pred[s->last_pict_type], rcc->last_qscale, sqrt(last_var), s->frame_bits);
616 if(s->flags&CODEC_FLAG_PASS2){
617 assert(picture_number>=0);
618 assert(picture_number<rcc->num_entries);
619 rce= &rcc->entry[picture_number];
620 wanted_bits= rce->expected_bits;
623 wanted_bits= (uint64_t)(s->bit_rate*(double)picture_number/fps);
626 diff= s->total_bits - wanted_bits;
627 br_compensation= (a->bit_rate_tolerance - diff)/a->bit_rate_tolerance;
628 if(br_compensation<=0.0) br_compensation=0.001;
630 var= pict_type == I_TYPE ? pic->mb_var_sum : pic->mc_mb_var_sum;
632 short_term_q = 0; /* avoid warning */
633 if(s->flags&CODEC_FLAG_PASS2){
634 if(pict_type!=I_TYPE)
635 assert(pict_type == rce->new_pict_type);
637 q= rce->new_qscale / br_compensation;
638 //printf("%f %f %f last:%d var:%d type:%d//\n", q, rce->new_qscale, br_compensation, s->frame_bits, var, pict_type);
641 rce->new_pict_type= pict_type;
642 rce->mc_mb_var_sum= pic->mc_mb_var_sum;
643 rce->mb_var_sum = pic-> mb_var_sum;
644 rce->qscale = FF_QP2LAMBDA * 2;
645 rce->f_code = s->f_code;
646 rce->b_code = s->b_code;
649 bits= predict_size(&rcc->pred[pict_type], rce->qscale, sqrt(var));
650 if(pict_type== I_TYPE){
651 rce->i_count = s->mb_num;
652 rce->i_tex_bits= bits;
656 rce->i_count = 0; //FIXME we do know this approx
658 rce->p_tex_bits= bits*0.9;
660 rce->mv_bits= bits*0.1;
662 rcc->i_cplx_sum [pict_type] += rce->i_tex_bits*rce->qscale;
663 rcc->p_cplx_sum [pict_type] += rce->p_tex_bits*rce->qscale;
664 rcc->mv_bits_sum[pict_type] += rce->mv_bits;
665 rcc->frame_count[pict_type] ++;
667 bits= rce->i_tex_bits + rce->p_tex_bits;
668 rate_factor= rcc->pass1_wanted_bits/rcc->pass1_rc_eq_output_sum * br_compensation;
670 q= get_qscale(s, rce, rate_factor, picture_number);
674 q= get_diff_limited_q(s, rce, q);
678 if(pict_type==P_TYPE || s->intra_only){ //FIXME type dependant blur like in 2-pass
679 rcc->short_term_qsum*=a->qblur;
680 rcc->short_term_qcount*=a->qblur;
682 rcc->short_term_qsum+= q;
683 rcc->short_term_qcount++;
685 q= short_term_q= rcc->short_term_qsum/rcc->short_term_qcount;
690 q= modify_qscale(s, rce, q, picture_number);
692 rcc->pass1_wanted_bits+= s->bit_rate/fps;
697 if(s->avctx->debug&FF_DEBUG_RC){
698 av_log(s->avctx, AV_LOG_DEBUG, "%c qp:%d<%2.1f<%d %d want:%d total:%d comp:%f st_q:%2.2f size:%d var:%d/%d br:%d fps:%d\n",
699 av_get_pict_type_char(pict_type), qmin, q, qmax, picture_number, (int)wanted_bits/1000, (int)s->total_bits/1000,
700 br_compensation, short_term_q, s->frame_bits, pic->mb_var_sum, pic->mc_mb_var_sum, s->bit_rate/1000, (int)fps
705 else if(q>qmax) q=qmax;
707 if(s->adaptive_quant)
708 adaptive_quantization(s, q);
713 rcc->last_mc_mb_var_sum= pic->mc_mb_var_sum;
714 rcc->last_mb_var_sum= pic->mb_var_sum;
717 static int mvsum=0, texsum=0;
719 texsum += s->i_tex_bits + s->p_tex_bits;
720 printf("%d %d//\n\n", mvsum, texsum);
726 //----------------------------------------------
729 static int init_pass2(MpegEncContext *s)
731 RateControlContext *rcc= &s->rc_context;
732 AVCodecContext *a= s->avctx;
734 double fps= (double)s->avctx->frame_rate / (double)s->avctx->frame_rate_base;
735 double complexity[5]={0,0,0,0,0}; // aproximate bits at quant=1
736 double avg_quantizer[5];
737 uint64_t const_bits[5]={0,0,0,0,0}; // quantizer idependant bits
738 uint64_t available_bits[5];
739 uint64_t all_const_bits;
740 uint64_t all_available_bits= (uint64_t)(s->bit_rate*(double)rcc->num_entries/fps);
741 double rate_factor=0;
743 //int last_i_frame=-10000000;
744 const int filter_size= (int)(a->qblur*4) | 1;
745 double expected_bits;
746 double *qscale, *blured_qscale;
748 /* find complexity & const_bits & decide the pict_types */
749 for(i=0; i<rcc->num_entries; i++){
750 RateControlEntry *rce= &rcc->entry[i];
752 rce->new_pict_type= rce->pict_type;
753 rcc->i_cplx_sum [rce->pict_type] += rce->i_tex_bits*rce->qscale;
754 rcc->p_cplx_sum [rce->pict_type] += rce->p_tex_bits*rce->qscale;
755 rcc->mv_bits_sum[rce->pict_type] += rce->mv_bits;
756 rcc->frame_count[rce->pict_type] ++;
758 complexity[rce->new_pict_type]+= (rce->i_tex_bits+ rce->p_tex_bits)*(double)rce->qscale;
759 const_bits[rce->new_pict_type]+= rce->mv_bits + rce->misc_bits;
761 all_const_bits= const_bits[I_TYPE] + const_bits[P_TYPE] + const_bits[B_TYPE];
763 if(all_available_bits < all_const_bits){
764 av_log(s->avctx, AV_LOG_ERROR, "requested bitrate is to low\n");
768 /* find average quantizers */
769 avg_quantizer[P_TYPE]=0;
770 for(step=256*256; step>0.0000001; step*=0.5){
771 double expected_bits=0;
772 avg_quantizer[P_TYPE]+= step;
774 avg_quantizer[I_TYPE]= avg_quantizer[P_TYPE]*ABS(s->avctx->i_quant_factor) + s->avctx->i_quant_offset;
775 avg_quantizer[B_TYPE]= avg_quantizer[P_TYPE]*ABS(s->avctx->b_quant_factor) + s->avctx->b_quant_offset;
779 + complexity[I_TYPE]/avg_quantizer[I_TYPE]
780 + complexity[P_TYPE]/avg_quantizer[P_TYPE]
781 + complexity[B_TYPE]/avg_quantizer[B_TYPE];
783 if(expected_bits < all_available_bits) avg_quantizer[P_TYPE]-= step;
784 //printf("%f %lld %f\n", expected_bits, all_available_bits, avg_quantizer[P_TYPE]);
786 //printf("qp_i:%f, qp_p:%f, qp_b:%f\n", avg_quantizer[I_TYPE],avg_quantizer[P_TYPE],avg_quantizer[B_TYPE]);
789 available_bits[i]= const_bits[i] + complexity[i]/avg_quantizer[i];
791 //printf("%lld %lld %lld %lld\n", available_bits[I_TYPE], available_bits[P_TYPE], available_bits[B_TYPE], all_available_bits);
793 qscale= av_malloc(sizeof(double)*rcc->num_entries);
794 blured_qscale= av_malloc(sizeof(double)*rcc->num_entries);
796 for(step=256*256; step>0.0000001; step*=0.5){
800 rcc->buffer_index= s->avctx->rc_buffer_size/2;
803 for(i=0; i<rcc->num_entries; i++){
804 qscale[i]= get_qscale(s, &rcc->entry[i], rate_factor, i);
806 assert(filter_size%2==1);
808 /* fixed I/B QP relative to P mode */
809 for(i=rcc->num_entries-1; i>=0; i--){
810 RateControlEntry *rce= &rcc->entry[i];
812 qscale[i]= get_diff_limited_q(s, rce, qscale[i]);
816 for(i=0; i<rcc->num_entries; i++){
817 RateControlEntry *rce= &rcc->entry[i];
818 const int pict_type= rce->new_pict_type;
820 double q=0.0, sum=0.0;
822 for(j=0; j<filter_size; j++){
823 int index= i+j-filter_size/2;
825 double coeff= a->qblur==0 ? 1.0 : exp(-d*d/(a->qblur * a->qblur));
827 if(index < 0 || index >= rcc->num_entries) continue;
828 if(pict_type != rcc->entry[index].new_pict_type) continue;
829 q+= qscale[index] * coeff;
832 blured_qscale[i]= q/sum;
835 /* find expected bits */
836 for(i=0; i<rcc->num_entries; i++){
837 RateControlEntry *rce= &rcc->entry[i];
839 rce->new_qscale= modify_qscale(s, rce, blured_qscale[i], i);
840 bits= qp2bits(rce, rce->new_qscale) + rce->mv_bits + rce->misc_bits;
841 //printf("%d %f\n", rce->new_bits, blured_qscale[i]);
842 bits += 8*ff_vbv_update(s, bits);
844 rce->expected_bits= expected_bits;
845 expected_bits += bits;
848 // printf("%f %d %f\n", expected_bits, (int)all_available_bits, rate_factor);
849 if(expected_bits > all_available_bits) rate_factor-= step;
852 av_free(blured_qscale);
854 if(abs(expected_bits/all_available_bits - 1.0) > 0.01 ){
855 av_log(s->avctx, AV_LOG_ERROR, "Error: 2pass curve failed to converge\n");