2 * Rate control for video encoders
4 * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
6 * This file is part of Libav.
8 * Libav is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
13 * Libav is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with Libav; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
25 * Rate control for video encoders.
28 #include "libavutil/intmath.h"
31 #include "ratecontrol.h"
32 #include "mpegvideo.h"
33 #include "libavutil/eval.h"
35 #undef NDEBUG // Always check asserts, the speed effect is far too small to disable them.
39 #define M_E 2.718281828
42 static int init_pass2(MpegEncContext *s);
43 static double get_qscale(MpegEncContext *s, RateControlEntry *rce, double rate_factor, int frame_num);
45 void ff_write_pass1_stats(MpegEncContext *s){
46 snprintf(s->avctx->stats_out, 256, "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 skipcount:%d hbits:%d;\n",
47 s->current_picture_ptr->f.display_picture_number, s->current_picture_ptr->f.coded_picture_number, s->pict_type,
48 s->current_picture.f.quality, s->i_tex_bits, s->p_tex_bits, s->mv_bits, s->misc_bits,
49 s->f_code, s->b_code, s->current_picture.mc_mb_var_sum, s->current_picture.mb_var_sum, s->i_count, s->skip_count, s->header_bits);
52 static inline double qp2bits(RateControlEntry *rce, double qp){
54 av_log(NULL, AV_LOG_ERROR, "qp<=0.0\n");
56 return rce->qscale * (double)(rce->i_tex_bits + rce->p_tex_bits+1)/ qp;
59 static inline double bits2qp(RateControlEntry *rce, double bits){
61 av_log(NULL, AV_LOG_ERROR, "bits<0.9\n");
63 return rce->qscale * (double)(rce->i_tex_bits + rce->p_tex_bits+1)/ bits;
66 int ff_rate_control_init(MpegEncContext *s)
68 RateControlContext *rcc= &s->rc_context;
70 static const char * const const_names[]={
97 static double (* const func1[])(void *, double)={
102 static const char * const func1_names[]={
109 res = av_expr_parse(&rcc->rc_eq_eval, s->avctx->rc_eq ? s->avctx->rc_eq : "tex^qComp", const_names, func1_names, func1, NULL, NULL, 0, s->avctx);
111 av_log(s->avctx, AV_LOG_ERROR, "Error parsing rc_eq \"%s\"\n", s->avctx->rc_eq);
116 rcc->pred[i].coeff= FF_QP2LAMBDA * 7.0;
117 rcc->pred[i].count= 1.0;
119 rcc->pred[i].decay= 0.4;
124 rcc->frame_count[i]= 1; // 1 is better because of 1/0 and such
125 rcc->last_qscale_for[i]=FF_QP2LAMBDA * 5;
127 rcc->buffer_index= s->avctx->rc_initial_buffer_occupancy;
129 if(s->flags&CODEC_FLAG_PASS2){
133 /* find number of pics */
134 p= s->avctx->stats_in;
139 if(i<=0 || i>=INT_MAX / sizeof(RateControlEntry))
141 rcc->entry = av_mallocz(i*sizeof(RateControlEntry));
144 /* init all to skipped p frames (with b frames we might have a not encoded frame at the end FIXME) */
145 for(i=0; i<rcc->num_entries; i++){
146 RateControlEntry *rce= &rcc->entry[i];
147 rce->pict_type= rce->new_pict_type=AV_PICTURE_TYPE_P;
148 rce->qscale= rce->new_qscale=FF_QP2LAMBDA * 2;
149 rce->misc_bits= s->mb_num + 10;
150 rce->mb_var_sum= s->mb_num*100;
154 p= s->avctx->stats_in;
155 for(i=0; i<rcc->num_entries - s->max_b_frames; i++){
156 RateControlEntry *rce;
161 next= strchr(p, ';');
163 (*next)=0; //sscanf in unbelievably slow on looong strings //FIXME copy / do not write
166 e= sscanf(p, " in:%d ", &picture_number);
168 assert(picture_number >= 0);
169 assert(picture_number < rcc->num_entries);
170 rce= &rcc->entry[picture_number];
172 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 skipcount:%d hbits:%d",
173 &rce->pict_type, &rce->qscale, &rce->i_tex_bits, &rce->p_tex_bits, &rce->mv_bits, &rce->misc_bits,
174 &rce->f_code, &rce->b_code, &rce->mc_mb_var_sum, &rce->mb_var_sum, &rce->i_count, &rce->skip_count, &rce->header_bits);
176 av_log(s->avctx, AV_LOG_ERROR, "statistics are damaged at line %d, parser out=%d\n", i, e);
183 if(init_pass2(s) < 0) return -1;
185 //FIXME maybe move to end
186 if((s->flags&CODEC_FLAG_PASS2) && s->avctx->rc_strategy == FF_RC_STRATEGY_XVID) {
188 return ff_xvid_rate_control_init(s);
190 av_log(s->avctx, AV_LOG_ERROR, "Xvid ratecontrol requires libavcodec compiled with Xvid support.\n");
196 if(!(s->flags&CODEC_FLAG_PASS2)){
198 rcc->short_term_qsum=0.001;
199 rcc->short_term_qcount=0.001;
201 rcc->pass1_rc_eq_output_sum= 0.001;
202 rcc->pass1_wanted_bits=0.001;
204 if(s->avctx->qblur > 1.0){
205 av_log(s->avctx, AV_LOG_ERROR, "qblur too large\n");
208 /* init stuff with the user specified complexity */
209 if(s->avctx->rc_initial_cplx){
210 for(i=0; i<60*30; i++){
211 double bits= s->avctx->rc_initial_cplx * (i/10000.0 + 1.0)*s->mb_num;
212 RateControlEntry rce;
214 if (i%((s->gop_size+3)/4)==0) rce.pict_type= AV_PICTURE_TYPE_I;
215 else if(i%(s->max_b_frames+1)) rce.pict_type= AV_PICTURE_TYPE_B;
216 else rce.pict_type= AV_PICTURE_TYPE_P;
218 rce.new_pict_type= rce.pict_type;
219 rce.mc_mb_var_sum= bits*s->mb_num/100000;
220 rce.mb_var_sum = s->mb_num;
221 rce.qscale = FF_QP2LAMBDA * 2;
226 if(s->pict_type== AV_PICTURE_TYPE_I){
227 rce.i_count = s->mb_num;
228 rce.i_tex_bits= bits;
232 rce.i_count = 0; //FIXME we do know this approx
234 rce.p_tex_bits= bits*0.9;
235 rce.mv_bits= bits*0.1;
237 rcc->i_cplx_sum [rce.pict_type] += rce.i_tex_bits*rce.qscale;
238 rcc->p_cplx_sum [rce.pict_type] += rce.p_tex_bits*rce.qscale;
239 rcc->mv_bits_sum[rce.pict_type] += rce.mv_bits;
240 rcc->frame_count[rce.pict_type] ++;
242 get_qscale(s, &rce, rcc->pass1_wanted_bits/rcc->pass1_rc_eq_output_sum, i);
243 rcc->pass1_wanted_bits+= s->bit_rate/(1/av_q2d(s->avctx->time_base)); //FIXME misbehaves a little for variable fps
252 void ff_rate_control_uninit(MpegEncContext *s)
254 RateControlContext *rcc= &s->rc_context;
257 av_expr_free(rcc->rc_eq_eval);
258 av_freep(&rcc->entry);
261 if((s->flags&CODEC_FLAG_PASS2) && s->avctx->rc_strategy == FF_RC_STRATEGY_XVID)
262 ff_xvid_rate_control_uninit(s);
266 int ff_vbv_update(MpegEncContext *s, int frame_size){
267 RateControlContext *rcc= &s->rc_context;
268 const double fps= 1/av_q2d(s->avctx->time_base);
269 const int buffer_size= s->avctx->rc_buffer_size;
270 const double min_rate= s->avctx->rc_min_rate/fps;
271 const double max_rate= s->avctx->rc_max_rate/fps;
273 av_dlog(s, "%d %f %d %f %f\n",
274 buffer_size, rcc->buffer_index, frame_size, min_rate, max_rate);
278 rcc->buffer_index-= frame_size;
279 if(rcc->buffer_index < 0){
280 av_log(s->avctx, AV_LOG_ERROR, "rc buffer underflow\n");
281 rcc->buffer_index= 0;
284 left= buffer_size - rcc->buffer_index - 1;
285 rcc->buffer_index += av_clip(left, min_rate, max_rate);
287 if(rcc->buffer_index > buffer_size){
288 int stuffing= ceil((rcc->buffer_index - buffer_size)/8);
290 if(stuffing < 4 && s->codec_id == AV_CODEC_ID_MPEG4)
292 rcc->buffer_index -= 8*stuffing;
294 if(s->avctx->debug & FF_DEBUG_RC)
295 av_log(s->avctx, AV_LOG_DEBUG, "stuffing %d bytes\n", stuffing);
304 * Modify the bitrate curve from pass1 for one frame.
306 static double get_qscale(MpegEncContext *s, RateControlEntry *rce, double rate_factor, int frame_num){
307 RateControlContext *rcc= &s->rc_context;
308 AVCodecContext *a= s->avctx;
310 const int pict_type= rce->new_pict_type;
311 const double mb_num= s->mb_num;
314 double const_values[]={
317 rce->i_tex_bits*rce->qscale,
318 rce->p_tex_bits*rce->qscale,
319 (rce->i_tex_bits + rce->p_tex_bits)*(double)rce->qscale,
321 rce->pict_type == AV_PICTURE_TYPE_B ? (rce->f_code + rce->b_code)*0.5 : rce->f_code,
323 rce->mc_mb_var_sum/mb_num,
324 rce->mb_var_sum/mb_num,
325 rce->pict_type == AV_PICTURE_TYPE_I,
326 rce->pict_type == AV_PICTURE_TYPE_P,
327 rce->pict_type == AV_PICTURE_TYPE_B,
328 rcc->qscale_sum[pict_type] / (double)rcc->frame_count[pict_type],
330 /* rcc->last_qscale_for[AV_PICTURE_TYPE_I],
331 rcc->last_qscale_for[AV_PICTURE_TYPE_P],
332 rcc->last_qscale_for[AV_PICTURE_TYPE_B],
333 rcc->next_non_b_qscale,*/
334 rcc->i_cplx_sum[AV_PICTURE_TYPE_I] / (double)rcc->frame_count[AV_PICTURE_TYPE_I],
335 rcc->i_cplx_sum[AV_PICTURE_TYPE_P] / (double)rcc->frame_count[AV_PICTURE_TYPE_P],
336 rcc->p_cplx_sum[AV_PICTURE_TYPE_P] / (double)rcc->frame_count[AV_PICTURE_TYPE_P],
337 rcc->p_cplx_sum[AV_PICTURE_TYPE_B] / (double)rcc->frame_count[AV_PICTURE_TYPE_B],
338 (rcc->i_cplx_sum[pict_type] + rcc->p_cplx_sum[pict_type]) / (double)rcc->frame_count[pict_type],
342 bits = av_expr_eval(rcc->rc_eq_eval, const_values, rce);
344 av_log(s->avctx, AV_LOG_ERROR, "Error evaluating rc_eq \"%s\"\n", s->avctx->rc_eq);
348 rcc->pass1_rc_eq_output_sum+= bits;
350 if(bits<0.0) bits=0.0;
351 bits+= 1.0; //avoid 1/0 issues
354 for(i=0; i<s->avctx->rc_override_count; i++){
355 RcOverride *rco= s->avctx->rc_override;
356 if(rco[i].start_frame > frame_num) continue;
357 if(rco[i].end_frame < frame_num) continue;
360 bits= qp2bits(rce, rco[i].qscale); //FIXME move at end to really force it?
362 bits*= rco[i].quality_factor;
365 q= bits2qp(rce, bits);
368 if (pict_type==AV_PICTURE_TYPE_I && s->avctx->i_quant_factor<0.0)
369 q= -q*s->avctx->i_quant_factor + s->avctx->i_quant_offset;
370 else if(pict_type==AV_PICTURE_TYPE_B && s->avctx->b_quant_factor<0.0)
371 q= -q*s->avctx->b_quant_factor + s->avctx->b_quant_offset;
377 static double get_diff_limited_q(MpegEncContext *s, RateControlEntry *rce, double q){
378 RateControlContext *rcc= &s->rc_context;
379 AVCodecContext *a= s->avctx;
380 const int pict_type= rce->new_pict_type;
381 const double last_p_q = rcc->last_qscale_for[AV_PICTURE_TYPE_P];
382 const double last_non_b_q= rcc->last_qscale_for[rcc->last_non_b_pict_type];
384 if (pict_type==AV_PICTURE_TYPE_I && (a->i_quant_factor>0.0 || rcc->last_non_b_pict_type==AV_PICTURE_TYPE_P))
385 q= last_p_q *FFABS(a->i_quant_factor) + a->i_quant_offset;
386 else if(pict_type==AV_PICTURE_TYPE_B && a->b_quant_factor>0.0)
387 q= last_non_b_q* a->b_quant_factor + a->b_quant_offset;
390 /* last qscale / qdiff stuff */
391 if(rcc->last_non_b_pict_type==pict_type || pict_type!=AV_PICTURE_TYPE_I){
392 double last_q= rcc->last_qscale_for[pict_type];
393 const int maxdiff= FF_QP2LAMBDA * a->max_qdiff;
395 if (q > last_q + maxdiff) q= last_q + maxdiff;
396 else if(q < last_q - maxdiff) q= last_q - maxdiff;
399 rcc->last_qscale_for[pict_type]= q; //Note we cannot do that after blurring
401 if(pict_type!=AV_PICTURE_TYPE_B)
402 rcc->last_non_b_pict_type= pict_type;
408 * Get the qmin & qmax for pict_type.
410 static void get_qminmax(int *qmin_ret, int *qmax_ret, MpegEncContext *s, int pict_type){
411 int qmin= s->avctx->lmin;
412 int qmax= s->avctx->lmax;
414 assert(qmin <= qmax);
416 if(pict_type==AV_PICTURE_TYPE_B){
417 qmin= (int)(qmin*FFABS(s->avctx->b_quant_factor)+s->avctx->b_quant_offset + 0.5);
418 qmax= (int)(qmax*FFABS(s->avctx->b_quant_factor)+s->avctx->b_quant_offset + 0.5);
419 }else if(pict_type==AV_PICTURE_TYPE_I){
420 qmin= (int)(qmin*FFABS(s->avctx->i_quant_factor)+s->avctx->i_quant_offset + 0.5);
421 qmax= (int)(qmax*FFABS(s->avctx->i_quant_factor)+s->avctx->i_quant_offset + 0.5);
424 qmin= av_clip(qmin, 1, FF_LAMBDA_MAX);
425 qmax= av_clip(qmax, 1, FF_LAMBDA_MAX);
427 if(qmax<qmin) qmax= qmin;
433 static double modify_qscale(MpegEncContext *s, RateControlEntry *rce, double q, int frame_num){
434 RateControlContext *rcc= &s->rc_context;
436 const int pict_type= rce->new_pict_type;
437 const double buffer_size= s->avctx->rc_buffer_size;
438 const double fps= 1/av_q2d(s->avctx->time_base);
439 const double min_rate= s->avctx->rc_min_rate / fps;
440 const double max_rate= s->avctx->rc_max_rate / fps;
442 get_qminmax(&qmin, &qmax, s, pict_type);
445 if(s->avctx->rc_qmod_freq && frame_num%s->avctx->rc_qmod_freq==0 && pict_type==AV_PICTURE_TYPE_P)
446 q*= s->avctx->rc_qmod_amp;
448 /* buffer overflow/underflow protection */
450 double expected_size= rcc->buffer_index;
454 double d= 2*(buffer_size - expected_size)/buffer_size;
456 else if(d<0.0001) d=0.0001;
457 q*= pow(d, 1.0/s->avctx->rc_buffer_aggressivity);
459 q_limit= bits2qp(rce, FFMAX((min_rate - buffer_size + rcc->buffer_index) * s->avctx->rc_min_vbv_overflow_use, 1));
461 if(s->avctx->debug&FF_DEBUG_RC){
462 av_log(s->avctx, AV_LOG_DEBUG, "limiting QP %f -> %f\n", q, q_limit);
469 double d= 2*expected_size/buffer_size;
471 else if(d<0.0001) d=0.0001;
472 q/= pow(d, 1.0/s->avctx->rc_buffer_aggressivity);
474 q_limit= bits2qp(rce, FFMAX(rcc->buffer_index * s->avctx->rc_max_available_vbv_use, 1));
476 if(s->avctx->debug&FF_DEBUG_RC){
477 av_log(s->avctx, AV_LOG_DEBUG, "limiting QP %f -> %f\n", q, q_limit);
483 av_dlog(s, "q:%f max:%f min:%f size:%f index:%f agr:%f\n",
484 q, max_rate, min_rate, buffer_size, rcc->buffer_index,
485 s->avctx->rc_buffer_aggressivity);
486 if(s->avctx->rc_qsquish==0.0 || qmin==qmax){
488 else if(q>qmax) q=qmax;
490 double min2= log(qmin);
491 double max2= log(qmax);
494 q= (q - min2)/(max2-min2) - 0.5;
496 q= 1.0/(1.0 + exp(q));
497 q= q*(max2-min2) + min2;
505 //----------------------------------
508 static double predict_size(Predictor *p, double q, double var)
510 return p->coeff*var / (q*p->count);
513 static void update_predictor(Predictor *p, double q, double var, double size)
515 double new_coeff= size*q / (var + 1);
521 p->coeff+= new_coeff;
524 static void adaptive_quantization(MpegEncContext *s, double q){
526 const float lumi_masking= s->avctx->lumi_masking / (128.0*128.0);
527 const float dark_masking= s->avctx->dark_masking / (128.0*128.0);
528 const float temp_cplx_masking= s->avctx->temporal_cplx_masking;
529 const float spatial_cplx_masking = s->avctx->spatial_cplx_masking;
530 const float p_masking = s->avctx->p_masking;
531 const float border_masking = s->avctx->border_masking;
534 float *cplx_tab = s->cplx_tab;
535 float *bits_tab = s->bits_tab;
536 const int qmin= s->avctx->mb_lmin;
537 const int qmax= s->avctx->mb_lmax;
538 Picture * const pic= &s->current_picture;
539 const int mb_width = s->mb_width;
540 const int mb_height = s->mb_height;
542 for(i=0; i<s->mb_num; i++){
543 const int mb_xy= s->mb_index2xy[i];
544 float temp_cplx= sqrt(pic->mc_mb_var[mb_xy]); //FIXME merge in pow()
545 float spat_cplx= sqrt(pic->mb_var[mb_xy]);
546 const int lumi= pic->mb_mean[mb_xy];
547 float bits, cplx, factor;
548 int mb_x = mb_xy % s->mb_stride;
549 int mb_y = mb_xy / s->mb_stride;
551 float mb_factor = 0.0;
552 if(spat_cplx < 4) spat_cplx= 4; //FIXME finetune
553 if(temp_cplx < 4) temp_cplx= 4; //FIXME finetune
555 if((s->mb_type[mb_xy]&CANDIDATE_MB_TYPE_INTRA)){//FIXME hq mode
557 factor= 1.0 + p_masking;
560 factor= pow(temp_cplx, - temp_cplx_masking);
562 factor*=pow(spat_cplx, - spatial_cplx_masking);
565 factor*= (1.0 - (lumi-128)*(lumi-128)*lumi_masking);
567 factor*= (1.0 - (lumi-128)*(lumi-128)*dark_masking);
569 if(mb_x < mb_width/5){
570 mb_distance = mb_width/5 - mb_x;
571 mb_factor = (float)mb_distance / (float)(mb_width/5);
572 }else if(mb_x > 4*mb_width/5){
573 mb_distance = mb_x - 4*mb_width/5;
574 mb_factor = (float)mb_distance / (float)(mb_width/5);
576 if(mb_y < mb_height/5){
577 mb_distance = mb_height/5 - mb_y;
578 mb_factor = FFMAX(mb_factor, (float)mb_distance / (float)(mb_height/5));
579 }else if(mb_y > 4*mb_height/5){
580 mb_distance = mb_y - 4*mb_height/5;
581 mb_factor = FFMAX(mb_factor, (float)mb_distance / (float)(mb_height/5));
584 factor*= 1.0 - border_masking*mb_factor;
586 if(factor<0.00001) factor= 0.00001;
595 /* handle qmin/qmax clipping */
596 if(s->flags&CODEC_FLAG_NORMALIZE_AQP){
597 float factor= bits_sum/cplx_sum;
598 for(i=0; i<s->mb_num; i++){
599 float newq= q*cplx_tab[i]/bits_tab[i];
603 bits_sum -= bits_tab[i];
604 cplx_sum -= cplx_tab[i]*q/qmax;
606 else if(newq < qmin){
607 bits_sum -= bits_tab[i];
608 cplx_sum -= cplx_tab[i]*q/qmin;
611 if(bits_sum < 0.001) bits_sum= 0.001;
612 if(cplx_sum < 0.001) cplx_sum= 0.001;
615 for(i=0; i<s->mb_num; i++){
616 const int mb_xy= s->mb_index2xy[i];
617 float newq= q*cplx_tab[i]/bits_tab[i];
620 if(s->flags&CODEC_FLAG_NORMALIZE_AQP){
621 newq*= bits_sum/cplx_sum;
624 intq= (int)(newq + 0.5);
626 if (intq > qmax) intq= qmax;
627 else if(intq < qmin) intq= qmin;
628 s->lambda_table[mb_xy]= intq;
632 void ff_get_2pass_fcode(MpegEncContext *s){
633 RateControlContext *rcc= &s->rc_context;
634 int picture_number= s->picture_number;
635 RateControlEntry *rce;
637 rce= &rcc->entry[picture_number];
638 s->f_code= rce->f_code;
639 s->b_code= rce->b_code;
642 //FIXME rd or at least approx for dquant
644 float ff_rate_estimate_qscale(MpegEncContext *s, int dry_run)
648 float br_compensation;
652 int picture_number= s->picture_number;
654 RateControlContext *rcc= &s->rc_context;
655 AVCodecContext *a= s->avctx;
656 RateControlEntry local_rce, *rce;
660 const int pict_type= s->pict_type;
661 Picture * const pic= &s->current_picture;
665 if((s->flags&CODEC_FLAG_PASS2) && s->avctx->rc_strategy == FF_RC_STRATEGY_XVID)
666 return ff_xvid_rate_estimate_qscale(s, dry_run);
669 get_qminmax(&qmin, &qmax, s, pict_type);
671 fps= 1/av_q2d(s->avctx->time_base);
672 /* update predictors */
673 if(picture_number>2 && !dry_run){
674 const int last_var= s->last_pict_type == AV_PICTURE_TYPE_I ? rcc->last_mb_var_sum : rcc->last_mc_mb_var_sum;
675 update_predictor(&rcc->pred[s->last_pict_type], rcc->last_qscale, sqrt(last_var), s->frame_bits);
678 if(s->flags&CODEC_FLAG_PASS2){
679 assert(picture_number>=0);
680 assert(picture_number<rcc->num_entries);
681 rce= &rcc->entry[picture_number];
682 wanted_bits= rce->expected_bits;
687 //FIXME add a dts field to AVFrame and ensure its set and use it here instead of reordering
688 //but the reordering is simpler for now until h.264 b pyramid must be handeld
689 if(s->pict_type == AV_PICTURE_TYPE_B || s->low_delay)
690 dts_pic= s->current_picture_ptr;
692 dts_pic= s->last_picture_ptr;
694 if (!dts_pic || dts_pic->f.pts == AV_NOPTS_VALUE)
695 wanted_bits= (uint64_t)(s->bit_rate*(double)picture_number/fps);
697 wanted_bits = (uint64_t)(s->bit_rate*(double)dts_pic->f.pts / fps);
700 diff= s->total_bits - wanted_bits;
701 br_compensation= (a->bit_rate_tolerance - diff)/a->bit_rate_tolerance;
702 if(br_compensation<=0.0) br_compensation=0.001;
704 var= pict_type == AV_PICTURE_TYPE_I ? pic->mb_var_sum : pic->mc_mb_var_sum;
706 short_term_q = 0; /* avoid warning */
707 if(s->flags&CODEC_FLAG_PASS2){
708 if(pict_type!=AV_PICTURE_TYPE_I)
709 assert(pict_type == rce->new_pict_type);
711 q= rce->new_qscale / br_compensation;
712 av_dlog(s, "%f %f %f last:%d var:%d type:%d//\n", q, rce->new_qscale,
713 br_compensation, s->frame_bits, var, pict_type);
716 rce->new_pict_type= pict_type;
717 rce->mc_mb_var_sum= pic->mc_mb_var_sum;
718 rce->mb_var_sum = pic-> mb_var_sum;
719 rce->qscale = FF_QP2LAMBDA * 2;
720 rce->f_code = s->f_code;
721 rce->b_code = s->b_code;
724 bits= predict_size(&rcc->pred[pict_type], rce->qscale, sqrt(var));
725 if(pict_type== AV_PICTURE_TYPE_I){
726 rce->i_count = s->mb_num;
727 rce->i_tex_bits= bits;
731 rce->i_count = 0; //FIXME we do know this approx
733 rce->p_tex_bits= bits*0.9;
735 rce->mv_bits= bits*0.1;
737 rcc->i_cplx_sum [pict_type] += rce->i_tex_bits*rce->qscale;
738 rcc->p_cplx_sum [pict_type] += rce->p_tex_bits*rce->qscale;
739 rcc->mv_bits_sum[pict_type] += rce->mv_bits;
740 rcc->frame_count[pict_type] ++;
742 bits= rce->i_tex_bits + rce->p_tex_bits;
743 rate_factor= rcc->pass1_wanted_bits/rcc->pass1_rc_eq_output_sum * br_compensation;
745 q= get_qscale(s, rce, rate_factor, picture_number);
750 q= get_diff_limited_q(s, rce, q);
753 if(pict_type==AV_PICTURE_TYPE_P || s->intra_only){ //FIXME type dependent blur like in 2-pass
754 rcc->short_term_qsum*=a->qblur;
755 rcc->short_term_qcount*=a->qblur;
757 rcc->short_term_qsum+= q;
758 rcc->short_term_qcount++;
759 q= short_term_q= rcc->short_term_qsum/rcc->short_term_qcount;
763 q= modify_qscale(s, rce, q, picture_number);
765 rcc->pass1_wanted_bits+= s->bit_rate/fps;
770 if(s->avctx->debug&FF_DEBUG_RC){
771 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",
772 av_get_picture_type_char(pict_type), qmin, q, qmax, picture_number, (int)wanted_bits/1000, (int)s->total_bits/1000,
773 br_compensation, short_term_q, s->frame_bits, pic->mb_var_sum, pic->mc_mb_var_sum, s->bit_rate/1000, (int)fps
778 else if(q>qmax) q=qmax;
780 if(s->adaptive_quant)
781 adaptive_quantization(s, q);
787 rcc->last_mc_mb_var_sum= pic->mc_mb_var_sum;
788 rcc->last_mb_var_sum= pic->mb_var_sum;
793 //----------------------------------------------
796 static int init_pass2(MpegEncContext *s)
798 RateControlContext *rcc= &s->rc_context;
799 AVCodecContext *a= s->avctx;
801 double fps= 1/av_q2d(s->avctx->time_base);
802 double complexity[5]={0,0,0,0,0}; // aproximate bits at quant=1
803 uint64_t const_bits[5]={0,0,0,0,0}; // quantizer independent bits
804 uint64_t all_const_bits;
805 uint64_t all_available_bits= (uint64_t)(s->bit_rate*(double)rcc->num_entries/fps);
806 double rate_factor=0;
808 //int last_i_frame=-10000000;
809 const int filter_size= (int)(a->qblur*4) | 1;
810 double expected_bits;
811 double *qscale, *blurred_qscale, qscale_sum;
813 /* find complexity & const_bits & decide the pict_types */
814 for(i=0; i<rcc->num_entries; i++){
815 RateControlEntry *rce= &rcc->entry[i];
817 rce->new_pict_type= rce->pict_type;
818 rcc->i_cplx_sum [rce->pict_type] += rce->i_tex_bits*rce->qscale;
819 rcc->p_cplx_sum [rce->pict_type] += rce->p_tex_bits*rce->qscale;
820 rcc->mv_bits_sum[rce->pict_type] += rce->mv_bits;
821 rcc->frame_count[rce->pict_type] ++;
823 complexity[rce->new_pict_type]+= (rce->i_tex_bits+ rce->p_tex_bits)*(double)rce->qscale;
824 const_bits[rce->new_pict_type]+= rce->mv_bits + rce->misc_bits;
826 all_const_bits= const_bits[AV_PICTURE_TYPE_I] + const_bits[AV_PICTURE_TYPE_P] + const_bits[AV_PICTURE_TYPE_B];
828 if(all_available_bits < all_const_bits){
829 av_log(s->avctx, AV_LOG_ERROR, "requested bitrate is too low\n");
833 qscale= av_malloc(sizeof(double)*rcc->num_entries);
834 blurred_qscale= av_malloc(sizeof(double)*rcc->num_entries);
837 for(step=256*256; step>0.0000001; step*=0.5){
841 rcc->buffer_index= s->avctx->rc_buffer_size/2;
844 for(i=0; i<rcc->num_entries; i++){
845 RateControlEntry *rce= &rcc->entry[i];
846 qscale[i]= get_qscale(s, &rcc->entry[i], rate_factor, i);
847 rcc->last_qscale_for[rce->pict_type] = qscale[i];
849 assert(filter_size%2==1);
851 /* fixed I/B QP relative to P mode */
852 for(i=rcc->num_entries-1; i>=0; i--){
853 RateControlEntry *rce= &rcc->entry[i];
855 qscale[i]= get_diff_limited_q(s, rce, qscale[i]);
859 for(i=0; i<rcc->num_entries; i++){
860 RateControlEntry *rce= &rcc->entry[i];
861 const int pict_type= rce->new_pict_type;
863 double q=0.0, sum=0.0;
865 for(j=0; j<filter_size; j++){
866 int index= i+j-filter_size/2;
868 double coeff= a->qblur==0 ? 1.0 : exp(-d*d/(a->qblur * a->qblur));
870 if(index < 0 || index >= rcc->num_entries) continue;
871 if(pict_type != rcc->entry[index].new_pict_type) continue;
872 q+= qscale[index] * coeff;
875 blurred_qscale[i]= q/sum;
878 /* find expected bits */
879 for(i=0; i<rcc->num_entries; i++){
880 RateControlEntry *rce= &rcc->entry[i];
882 rce->new_qscale= modify_qscale(s, rce, blurred_qscale[i], i);
883 bits= qp2bits(rce, rce->new_qscale) + rce->mv_bits + rce->misc_bits;
884 bits += 8*ff_vbv_update(s, bits);
886 rce->expected_bits= expected_bits;
887 expected_bits += bits;
891 "expected_bits: %f all_available_bits: %d rate_factor: %f\n",
892 expected_bits, (int)all_available_bits, rate_factor);
893 if(expected_bits > all_available_bits) {
899 av_free(blurred_qscale);
901 /* check bitrate calculations and print info */
903 for(i=0; i<rcc->num_entries; i++){
904 av_dlog(s, "[lavc rc] entry[%d].new_qscale = %.3f qp = %.3f\n",
906 rcc->entry[i].new_qscale,
907 rcc->entry[i].new_qscale / FF_QP2LAMBDA);
908 qscale_sum += av_clip(rcc->entry[i].new_qscale / FF_QP2LAMBDA, s->avctx->qmin, s->avctx->qmax);
910 assert(toobig <= 40);
911 av_log(s->avctx, AV_LOG_DEBUG,
912 "[lavc rc] requested bitrate: %d bps expected bitrate: %d bps\n",
914 (int)(expected_bits / ((double)all_available_bits/s->bit_rate)));
915 av_log(s->avctx, AV_LOG_DEBUG,
916 "[lavc rc] estimated target average qp: %.3f\n",
917 (float)qscale_sum / rcc->num_entries);
919 av_log(s->avctx, AV_LOG_INFO,
920 "[lavc rc] Using all of requested bitrate is not "
921 "necessary for this video with these parameters.\n");
922 } else if (toobig == 40) {
923 av_log(s->avctx, AV_LOG_ERROR,
924 "[lavc rc] Error: bitrate too low for this video "
925 "with these parameters.\n");
927 } else if (fabs(expected_bits/all_available_bits - 1.0) > 0.01) {
928 av_log(s->avctx, AV_LOG_ERROR,
929 "[lavc rc] Error: 2pass curve failed to converge\n");