libavcodec/ratecontrol.c

   1 /*
   2  * Rate control for video encoders
   3  *
   4  * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
   5  *
   6  * This file is part of FFmpeg.
   7  *
   8  * FFmpeg 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.
  12  *
  13  * FFmpeg 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.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with FFmpeg; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  21  */
  22
  23 /**
  24  * @file ratecontrol.c
  25  * Rate control for video encoders.
  26  */
  27
  28 #include "avcodec.h"
  29 #include "dsputil.h"
  30 #include "ratecontrol.h"
  31 #include "mpegvideo.h"
  32 #include "eval.h"
  33
  34 #undef NDEBUG // Always check asserts, the speed effect is far too small to disable them.
  35 #include <assert.h>
  36
  37 #ifndef M_E
  38 #define M_E 2.718281828
  39 #endif
  40
  41 static int init_pass2(MpegEncContext *s);
  42 static double get_qscale(MpegEncContext *s, RateControlEntry *rce, double rate_factor, int frame_num);
  43
  44 void ff_write_pass1_stats(MpegEncContext *s){
  45     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",
  46             s->current_picture_ptr->display_picture_number, s->current_picture_ptr->coded_picture_number, s->pict_type,
  47             s->current_picture.quality, s->i_tex_bits, s->p_tex_bits, s->mv_bits, s->misc_bits,
  48             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);
  49 }
  50
  51 static inline double qp2bits(RateControlEntry *rce, double qp){
  52     if(qp<=0.0){
  53         av_log(NULL, AV_LOG_ERROR, "qp<=0.0\n");
  54     }
  55     return rce->qscale * (double)(rce->i_tex_bits + rce->p_tex_bits+1)/ qp;
  56 }
  57
  58 static inline double bits2qp(RateControlEntry *rce, double bits){
  59     if(bits<0.9){
  60         av_log(NULL, AV_LOG_ERROR, "bits<0.9\n");
  61     }
  62     return rce->qscale * (double)(rce->i_tex_bits + rce->p_tex_bits+1)/ bits;
  63 }
  64
  65 int ff_rate_control_init(MpegEncContext *s)
  66 {
  67     RateControlContext *rcc= &s->rc_context;
  68     int i;
  69     const char *error = NULL;
  70     static const char * const const_names[]={
  71         "PI",
  72         "E",
  73         "iTex",
  74         "pTex",
  75         "tex",
  76         "mv",
  77         "fCode",
  78         "iCount",
  79         "mcVar",
  80         "var",
  81         "isI",
  82         "isP",
  83         "isB",
  84         "avgQP",
  85         "qComp",
  86 /*        "lastIQP",
  87         "lastPQP",
  88         "lastBQP",
  89         "nextNonBQP",*/
  90         "avgIITex",
  91         "avgPITex",
  92         "avgPPTex",
  93         "avgBPTex",
  94         "avgTex",
  95         NULL
  96     };
  97     static double (*func1[])(void *, double)={
  98         (void *)bits2qp,
  99         (void *)qp2bits,
 100         NULL
 101     };
 102     static const char * const func1_names[]={
 103         "bits2qp",
 104         "qp2bits",
 105         NULL
 106     };
 107     emms_c();
 108
 109     rcc->rc_eq_eval = ff_parse(s->avctx->rc_eq, const_names, func1, func1_names, NULL, NULL, &error);
 110     if (!rcc->rc_eq_eval) {
 111         av_log(s->avctx, AV_LOG_ERROR, "Error parsing rc_eq \"%s\": %s\n", s->avctx->rc_eq, error? error : "");
 112         return -1;
 113     }
 114
 115     for(i=0; i<5; i++){
 116         rcc->pred[i].coeff= FF_QP2LAMBDA * 7.0;
 117         rcc->pred[i].count= 1.0;
 118
 119         rcc->pred[i].decay= 0.4;
 120         rcc->i_cplx_sum [i]=
 121         rcc->p_cplx_sum [i]=
 122         rcc->mv_bits_sum[i]=
 123         rcc->qscale_sum [i]=
 124         rcc->frame_count[i]= 1; // 1 is better because of 1/0 and such
 125         rcc->last_qscale_for[i]=FF_QP2LAMBDA * 5;
 126     }
 127     rcc->buffer_index= s->avctx->rc_initial_buffer_occupancy;
 128
 129     if(s->flags&CODEC_FLAG_PASS2){
 130         int i;
 131         char *p;
 132
 133         /* find number of pics */
 134         p= s->avctx->stats_in;
 135         for(i=-1; p; i++){
 136             p= strchr(p+1, ';');
 137         }
 138         i+= s->max_b_frames;
 139         if(i<=0 || i>=INT_MAX / sizeof(RateControlEntry))
 140             return -1;
 141         rcc->entry = av_mallocz(i*sizeof(RateControlEntry));
 142         rcc->num_entries= i;
 143
 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=FF_P_TYPE;
 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;
 151         }
 152
 153         /* read stats */
 154         p= s->avctx->stats_in;
 155         for(i=0; i<rcc->num_entries - s->max_b_frames; i++){
 156             RateControlEntry *rce;
 157             int picture_number;
 158             int e;
 159             char *next;
 160
 161             next= strchr(p, ';');
 162             if(next){
 163                 (*next)=0; //sscanf in unbelievably slow on looong strings //FIXME copy / do not write
 164                 next++;
 165             }
 166             e= sscanf(p, " in:%d ", &picture_number);
 167
 168             assert(picture_number >= 0);
 169             assert(picture_number < rcc->num_entries);
 170             rce= &rcc->entry[picture_number];
 171
 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);
 175             if(e!=14){
 176                 av_log(s->avctx, AV_LOG_ERROR, "statistics are damaged at line %d, parser out=%d\n", i, e);
 177                 return -1;
 178             }
 179
 180             p= next;
 181         }
 182
 183         if(init_pass2(s) < 0) return -1;
 184
 185         //FIXME maybe move to end
 186         if((s->flags&CODEC_FLAG_PASS2) && s->avctx->rc_strategy == FF_RC_STRATEGY_XVID) {
 187 #ifdef CONFIG_LIBXVID
 188             return ff_xvid_rate_control_init(s);
 189 #else
 190             av_log(s->avctx, AV_LOG_ERROR, "Xvid ratecontrol requires libavcodec compiled with Xvid support.\n");
 191             return -1;
 192 #endif
 193         }
 194     }
 195
 196     if(!(s->flags&CODEC_FLAG_PASS2)){
 197
 198         rcc->short_term_qsum=0.001;
 199         rcc->short_term_qcount=0.001;
 200
 201         rcc->pass1_rc_eq_output_sum= 0.001;
 202         rcc->pass1_wanted_bits=0.001;
 203
 204         if(s->avctx->qblur > 1.0){
 205             av_log(s->avctx, AV_LOG_ERROR, "qblur too large\n");
 206             return -1;
 207         }
 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;
 213                 double q;
 214
 215                 if     (i%((s->gop_size+3)/4)==0) rce.pict_type= FF_I_TYPE;
 216                 else if(i%(s->max_b_frames+1))    rce.pict_type= FF_B_TYPE;
 217                 else                              rce.pict_type= FF_P_TYPE;
 218
 219                 rce.new_pict_type= rce.pict_type;
 220                 rce.mc_mb_var_sum= bits*s->mb_num/100000;
 221                 rce.mb_var_sum   = s->mb_num;
 222                 rce.qscale   = FF_QP2LAMBDA * 2;
 223                 rce.f_code   = 2;
 224                 rce.b_code   = 1;
 225                 rce.misc_bits= 1;
 226
 227                 if(s->pict_type== FF_I_TYPE){
 228                     rce.i_count   = s->mb_num;
 229                     rce.i_tex_bits= bits;
 230                     rce.p_tex_bits= 0;
 231                     rce.mv_bits= 0;
 232                 }else{
 233                     rce.i_count   = 0; //FIXME we do know this approx
 234                     rce.i_tex_bits= 0;
 235                     rce.p_tex_bits= bits*0.9;
 236                     rce.mv_bits= bits*0.1;
 237                 }
 238                 rcc->i_cplx_sum [rce.pict_type] += rce.i_tex_bits*rce.qscale;
 239                 rcc->p_cplx_sum [rce.pict_type] += rce.p_tex_bits*rce.qscale;
 240                 rcc->mv_bits_sum[rce.pict_type] += rce.mv_bits;
 241                 rcc->frame_count[rce.pict_type] ++;
 242
 243                 bits= rce.i_tex_bits + rce.p_tex_bits;
 244
 245                 q= get_qscale(s, &rce, rcc->pass1_wanted_bits/rcc->pass1_rc_eq_output_sum, i);
 246                 rcc->pass1_wanted_bits+= s->bit_rate/(1/av_q2d(s->avctx->time_base)); //FIXME misbehaves a little for variable fps
 247             }
 248         }
 249
 250     }
 251
 252     return 0;
 253 }
 254
 255 void ff_rate_control_uninit(MpegEncContext *s)
 256 {
 257     RateControlContext *rcc= &s->rc_context;
 258     emms_c();
 259
 260     ff_eval_free(rcc->rc_eq_eval);
 261     av_freep(&rcc->entry);
 262
 263 #ifdef CONFIG_LIBXVID
 264     if((s->flags&CODEC_FLAG_PASS2) && s->avctx->rc_strategy == FF_RC_STRATEGY_XVID)
 265         ff_xvid_rate_control_uninit(s);
 266 #endif
 267 }
 268
 269 int ff_vbv_update(MpegEncContext *s, int frame_size){
 270     RateControlContext *rcc= &s->rc_context;
 271     const double fps= 1/av_q2d(s->avctx->time_base);
 272     const int buffer_size= s->avctx->rc_buffer_size;
 273     const double min_rate= s->avctx->rc_min_rate/fps;
 274     const double max_rate= s->avctx->rc_max_rate/fps;
 275
 276 //printf("%d %f %d %f %f\n", buffer_size, rcc->buffer_index, frame_size, min_rate, max_rate);
 277     if(buffer_size){
 278         int left;
 279
 280         rcc->buffer_index-= frame_size;
 281         if(rcc->buffer_index < 0){
 282             av_log(s->avctx, AV_LOG_ERROR, "rc buffer underflow\n");
 283             rcc->buffer_index= 0;
 284         }
 285
 286         left= buffer_size - rcc->buffer_index - 1;
 287         rcc->buffer_index += av_clip(left, min_rate, max_rate);
 288
 289         if(rcc->buffer_index > buffer_size){
 290             int stuffing= ceil((rcc->buffer_index - buffer_size)/8);
 291
 292             if(stuffing < 4 && s->codec_id == CODEC_ID_MPEG4)
 293                 stuffing=4;
 294             rcc->buffer_index -= 8*stuffing;
 295
 296             if(s->avctx->debug & FF_DEBUG_RC)
 297                 av_log(s->avctx, AV_LOG_DEBUG, "stuffing %d bytes\n", stuffing);
 298
 299             return stuffing;
 300         }
 301     }
 302     return 0;
 303 }
 304
 305 /**
 306  * modifies the bitrate curve from pass1 for one frame
 307  */
 308 static double get_qscale(MpegEncContext *s, RateControlEntry *rce, double rate_factor, int frame_num){
 309     RateControlContext *rcc= &s->rc_context;
 310     AVCodecContext *a= s->avctx;
 311     double q, bits;
 312     const int pict_type= rce->new_pict_type;
 313     const double mb_num= s->mb_num;
 314     int i;
 315
 316     double const_values[]={
 317         M_PI,
 318         M_E,
 319         rce->i_tex_bits*rce->qscale,
 320         rce->p_tex_bits*rce->qscale,
 321         (rce->i_tex_bits + rce->p_tex_bits)*(double)rce->qscale,
 322         rce->mv_bits/mb_num,
 323         rce->pict_type == FF_B_TYPE ? (rce->f_code + rce->b_code)*0.5 : rce->f_code,
 324         rce->i_count/mb_num,
 325         rce->mc_mb_var_sum/mb_num,
 326         rce->mb_var_sum/mb_num,
 327         rce->pict_type == FF_I_TYPE,
 328         rce->pict_type == FF_P_TYPE,
 329         rce->pict_type == FF_B_TYPE,
 330         rcc->qscale_sum[pict_type] / (double)rcc->frame_count[pict_type],
 331         a->qcompress,
 332 /*        rcc->last_qscale_for[FF_I_TYPE],
 333         rcc->last_qscale_for[FF_P_TYPE],
 334         rcc->last_qscale_for[FF_B_TYPE],
 335         rcc->next_non_b_qscale,*/
 336         rcc->i_cplx_sum[FF_I_TYPE] / (double)rcc->frame_count[FF_I_TYPE],
 337         rcc->i_cplx_sum[FF_P_TYPE] / (double)rcc->frame_count[FF_P_TYPE],
 338         rcc->p_cplx_sum[FF_P_TYPE] / (double)rcc->frame_count[FF_P_TYPE],
 339         rcc->p_cplx_sum[FF_B_TYPE] / (double)rcc->frame_count[FF_B_TYPE],
 340         (rcc->i_cplx_sum[pict_type] + rcc->p_cplx_sum[pict_type]) / (double)rcc->frame_count[pict_type],
 341         0
 342     };
 343
 344     bits= ff_parse_eval(rcc->rc_eq_eval, const_values, rce);
 345     if (isnan(bits)) {
 346         av_log(s->avctx, AV_LOG_ERROR, "Error evaluating rc_eq \"%s\"\n", s->avctx->rc_eq);
 347         return -1;
 348     }
 349
 350     rcc->pass1_rc_eq_output_sum+= bits;
 351     bits*=rate_factor;
 352     if(bits<0.0) bits=0.0;
 353     bits+= 1.0; //avoid 1/0 issues
 354
 355     /* user override */
 356     for(i=0; i<s->avctx->rc_override_count; i++){
 357         RcOverride *rco= s->avctx->rc_override;
 358         if(rco[i].start_frame > frame_num) continue;
 359         if(rco[i].end_frame   < frame_num) continue;
 360
 361         if(rco[i].qscale)
 362             bits= qp2bits(rce, rco[i].qscale); //FIXME move at end to really force it?
 363         else
 364             bits*= rco[i].quality_factor;
 365     }
 366
 367     q= bits2qp(rce, bits);
 368
 369     /* I/B difference */
 370     if     (pict_type==FF_I_TYPE && s->avctx->i_quant_factor<0.0)
 371         q= -q*s->avctx->i_quant_factor + s->avctx->i_quant_offset;
 372     else if(pict_type==FF_B_TYPE && s->avctx->b_quant_factor<0.0)
 373         q= -q*s->avctx->b_quant_factor + s->avctx->b_quant_offset;
 374     if(q<1) q=1;
 375
 376     return q;
 377 }
 378
 379 static double get_diff_limited_q(MpegEncContext *s, RateControlEntry *rce, double q){
 380     RateControlContext *rcc= &s->rc_context;
 381     AVCodecContext *a= s->avctx;
 382     const int pict_type= rce->new_pict_type;
 383     const double last_p_q    = rcc->last_qscale_for[FF_P_TYPE];
 384     const double last_non_b_q= rcc->last_qscale_for[rcc->last_non_b_pict_type];
 385
 386     if     (pict_type==FF_I_TYPE && (a->i_quant_factor>0.0 || rcc->last_non_b_pict_type==FF_P_TYPE))
 387         q= last_p_q    *FFABS(a->i_quant_factor) + a->i_quant_offset;
 388     else if(pict_type==FF_B_TYPE && a->b_quant_factor>0.0)
 389         q= last_non_b_q*    a->b_quant_factor  + a->b_quant_offset;
 390     if(q<1) q=1;
 391
 392     /* last qscale / qdiff stuff */
 393     if(rcc->last_non_b_pict_type==pict_type || pict_type!=FF_I_TYPE){
 394         double last_q= rcc->last_qscale_for[pict_type];
 395         const int maxdiff= FF_QP2LAMBDA * a->max_qdiff;
 396
 397         if     (q > last_q + maxdiff) q= last_q + maxdiff;
 398         else if(q < last_q - maxdiff) q= last_q - maxdiff;
 399     }
 400
 401     rcc->last_qscale_for[pict_type]= q; //Note we cannot do that after blurring
 402
 403     if(pict_type!=FF_B_TYPE)
 404         rcc->last_non_b_pict_type= pict_type;
 405
 406     return q;
 407 }
 408
 409 /**
 410  * gets the qmin & qmax for pict_type
 411  */
 412 static void get_qminmax(int *qmin_ret, int *qmax_ret, MpegEncContext *s, int pict_type){
 413     int qmin= s->avctx->lmin;
 414     int qmax= s->avctx->lmax;
 415
 416     assert(qmin <= qmax);
 417
 418     if(pict_type==FF_B_TYPE){
 419         qmin= (int)(qmin*FFABS(s->avctx->b_quant_factor)+s->avctx->b_quant_offset + 0.5);
 420         qmax= (int)(qmax*FFABS(s->avctx->b_quant_factor)+s->avctx->b_quant_offset + 0.5);
 421     }else if(pict_type==FF_I_TYPE){
 422         qmin= (int)(qmin*FFABS(s->avctx->i_quant_factor)+s->avctx->i_quant_offset + 0.5);
 423         qmax= (int)(qmax*FFABS(s->avctx->i_quant_factor)+s->avctx->i_quant_offset + 0.5);
 424     }
 425
 426     qmin= av_clip(qmin, 1, FF_LAMBDA_MAX);
 427     qmax= av_clip(qmax, 1, FF_LAMBDA_MAX);
 428
 429     if(qmax<qmin) qmax= qmin;
 430
 431     *qmin_ret= qmin;
 432     *qmax_ret= qmax;
 433 }
 434
 435 static double modify_qscale(MpegEncContext *s, RateControlEntry *rce, double q, int frame_num){
 436     RateControlContext *rcc= &s->rc_context;
 437     int qmin, qmax;
 438     double bits;
 439     const int pict_type= rce->new_pict_type;
 440     const double buffer_size= s->avctx->rc_buffer_size;
 441     const double fps= 1/av_q2d(s->avctx->time_base);
 442     const double min_rate= s->avctx->rc_min_rate / fps;
 443     const double max_rate= s->avctx->rc_max_rate / fps;
 444
 445     get_qminmax(&qmin, &qmax, s, pict_type);
 446
 447     /* modulation */
 448     if(s->avctx->rc_qmod_freq && frame_num%s->avctx->rc_qmod_freq==0 && pict_type==FF_P_TYPE)
 449         q*= s->avctx->rc_qmod_amp;
 450
 451     bits= qp2bits(rce, q);
 452 //printf("q:%f\n", q);
 453     /* buffer overflow/underflow protection */
 454     if(buffer_size){
 455         double expected_size= rcc->buffer_index;
 456         double q_limit;
 457
 458         if(min_rate){
 459             double d= 2*(buffer_size - expected_size)/buffer_size;
 460             if(d>1.0) d=1.0;
 461             else if(d<0.0001) d=0.0001;
 462             q*= pow(d, 1.0/s->avctx->rc_buffer_aggressivity);
 463
 464             q_limit= bits2qp(rce, FFMAX((min_rate - buffer_size + rcc->buffer_index)*3, 1));
 465             if(q > q_limit){
 466                 if(s->avctx->debug&FF_DEBUG_RC){
 467                     av_log(s->avctx, AV_LOG_DEBUG, "limiting QP %f -> %f\n", q, q_limit);
 468                 }
 469                 q= q_limit;
 470             }
 471         }
 472
 473         if(max_rate){
 474             double d= 2*expected_size/buffer_size;
 475             if(d>1.0) d=1.0;
 476             else if(d<0.0001) d=0.0001;
 477             q/= pow(d, 1.0/s->avctx->rc_buffer_aggressivity);
 478
 479             q_limit= bits2qp(rce, FFMAX(rcc->buffer_index/3, 1));
 480             if(q < q_limit){
 481                 if(s->avctx->debug&FF_DEBUG_RC){
 482                     av_log(s->avctx, AV_LOG_DEBUG, "limiting QP %f -> %f\n", q, q_limit);
 483                 }
 484                 q= q_limit;
 485             }
 486         }
 487     }
 488 //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);
 489     if(s->avctx->rc_qsquish==0.0 || qmin==qmax){
 490         if     (q<qmin) q=qmin;
 491         else if(q>qmax) q=qmax;
 492     }else{
 493         double min2= log(qmin);
 494         double max2= log(qmax);
 495
 496         q= log(q);
 497         q= (q - min2)/(max2-min2) - 0.5;
 498         q*= -4.0;
 499         q= 1.0/(1.0 + exp(q));
 500         q= q*(max2-min2) + min2;
 501
 502         q= exp(q);
 503     }
 504
 505     return q;
 506 }
 507
 508 //----------------------------------
 509 // 1 Pass Code
 510
 511 static double predict_size(Predictor *p, double q, double var)
 512 {
 513      return p->coeff*var / (q*p->count);
 514 }
 515
 516 /*
 517 static double predict_qp(Predictor *p, double size, double var)
 518 {
 519 //printf("coeff:%f, count:%f, var:%f, size:%f//\n", p->coeff, p->count, var, size);
 520      return p->coeff*var / (size*p->count);
 521 }
 522 */
 523
 524 static void update_predictor(Predictor *p, double q, double var, double size)
 525 {
 526     double new_coeff= size*q / (var + 1);
 527     if(var<10) return;
 528
 529     p->count*= p->decay;
 530     p->coeff*= p->decay;
 531     p->count++;
 532     p->coeff+= new_coeff;
 533 }
 534
 535 static void adaptive_quantization(MpegEncContext *s, double q){
 536     int i;
 537     const float lumi_masking= s->avctx->lumi_masking / (128.0*128.0);
 538     const float dark_masking= s->avctx->dark_masking / (128.0*128.0);
 539     const float temp_cplx_masking= s->avctx->temporal_cplx_masking;
 540     const float spatial_cplx_masking = s->avctx->spatial_cplx_masking;
 541     const float p_masking = s->avctx->p_masking;
 542     const float border_masking = s->avctx->border_masking;
 543     float bits_sum= 0.0;
 544     float cplx_sum= 0.0;
 545     float cplx_tab[s->mb_num];
 546     float bits_tab[s->mb_num];
 547     const int qmin= s->avctx->mb_lmin;
 548     const int qmax= s->avctx->mb_lmax;
 549     Picture * const pic= &s->current_picture;
 550     const int mb_width = s->mb_width;
 551     const int mb_height = s->mb_height;
 552
 553     for(i=0; i<s->mb_num; i++){
 554         const int mb_xy= s->mb_index2xy[i];
 555         float temp_cplx= sqrt(pic->mc_mb_var[mb_xy]); //FIXME merge in pow()
 556         float spat_cplx= sqrt(pic->mb_var[mb_xy]);
 557         const int lumi= pic->mb_mean[mb_xy];
 558         float bits, cplx, factor;
 559         int mb_x = mb_xy % s->mb_stride;
 560         int mb_y = mb_xy / s->mb_stride;
 561         int mb_distance;
 562         float mb_factor = 0.0;
 563 #if 0
 564         if(spat_cplx < q/3) spat_cplx= q/3; //FIXME finetune
 565         if(temp_cplx < q/3) temp_cplx= q/3; //FIXME finetune
 566 #endif
 567         if(spat_cplx < 4) spat_cplx= 4; //FIXME finetune
 568         if(temp_cplx < 4) temp_cplx= 4; //FIXME finetune
 569
 570         if((s->mb_type[mb_xy]&CANDIDATE_MB_TYPE_INTRA)){//FIXME hq mode
 571             cplx= spat_cplx;
 572             factor= 1.0 + p_masking;
 573         }else{
 574             cplx= temp_cplx;
 575             factor= pow(temp_cplx, - temp_cplx_masking);
 576         }
 577         factor*=pow(spat_cplx, - spatial_cplx_masking);
 578
 579         if(lumi>127)
 580             factor*= (1.0 - (lumi-128)*(lumi-128)*lumi_masking);
 581         else
 582             factor*= (1.0 - (lumi-128)*(lumi-128)*dark_masking);
 583
 584         if(mb_x < mb_width/5){
 585             mb_distance = mb_width/5 - mb_x;
 586             mb_factor = (float)mb_distance / (float)(mb_width/5);
 587         }else if(mb_x > 4*mb_width/5){
 588             mb_distance = mb_x - 4*mb_width/5;
 589             mb_factor = (float)mb_distance / (float)(mb_width/5);
 590         }
 591         if(mb_y < mb_height/5){
 592             mb_distance = mb_height/5 - mb_y;
 593             mb_factor = FFMAX(mb_factor, (float)mb_distance / (float)(mb_height/5));
 594         }else if(mb_y > 4*mb_height/5){
 595             mb_distance = mb_y - 4*mb_height/5;
 596             mb_factor = FFMAX(mb_factor, (float)mb_distance / (float)(mb_height/5));
 597         }
 598
 599         factor*= 1.0 - border_masking*mb_factor;
 600
 601         if(factor<0.00001) factor= 0.00001;
 602
 603         bits= cplx*factor;
 604         cplx_sum+= cplx;
 605         bits_sum+= bits;
 606         cplx_tab[i]= cplx;
 607         bits_tab[i]= bits;
 608     }
 609
 610     /* handle qmin/qmax clipping */
 611     if(s->flags&CODEC_FLAG_NORMALIZE_AQP){
 612         float factor= bits_sum/cplx_sum;
 613         for(i=0; i<s->mb_num; i++){
 614             float newq= q*cplx_tab[i]/bits_tab[i];
 615             newq*= factor;
 616
 617             if     (newq > qmax){
 618                 bits_sum -= bits_tab[i];
 619                 cplx_sum -= cplx_tab[i]*q/qmax;
 620             }
 621             else if(newq < qmin){
 622                 bits_sum -= bits_tab[i];
 623                 cplx_sum -= cplx_tab[i]*q/qmin;
 624             }
 625         }
 626         if(bits_sum < 0.001) bits_sum= 0.001;
 627         if(cplx_sum < 0.001) cplx_sum= 0.001;
 628     }
 629
 630     for(i=0; i<s->mb_num; i++){
 631         const int mb_xy= s->mb_index2xy[i];
 632         float newq= q*cplx_tab[i]/bits_tab[i];
 633         int intq;
 634
 635         if(s->flags&CODEC_FLAG_NORMALIZE_AQP){
 636             newq*= bits_sum/cplx_sum;
 637         }
 638
 639         intq= (int)(newq + 0.5);
 640
 641         if     (intq > qmax) intq= qmax;
 642         else if(intq < qmin) intq= qmin;
 643 //if(i%s->mb_width==0) printf("\n");
 644 //printf("%2d%3d ", intq, ff_sqrt(s->mc_mb_var[i]));
 645         s->lambda_table[mb_xy]= intq;
 646     }
 647 }
 648
 649 void ff_get_2pass_fcode(MpegEncContext *s){
 650     RateControlContext *rcc= &s->rc_context;
 651     int picture_number= s->picture_number;
 652     RateControlEntry *rce;
 653
 654     rce= &rcc->entry[picture_number];
 655     s->f_code= rce->f_code;
 656     s->b_code= rce->b_code;
 657 }
 658
 659 //FIXME rd or at least approx for dquant
 660
 661 float ff_rate_estimate_qscale(MpegEncContext *s, int dry_run)
 662 {
 663     float q;
 664     int qmin, qmax;
 665     float br_compensation;
 666     double diff;
 667     double short_term_q;
 668     double fps;
 669     int picture_number= s->picture_number;
 670     int64_t wanted_bits;
 671     RateControlContext *rcc= &s->rc_context;
 672     AVCodecContext *a= s->avctx;
 673     RateControlEntry local_rce, *rce;
 674     double bits;
 675     double rate_factor;
 676     int var;
 677     const int pict_type= s->pict_type;
 678     Picture * const pic= &s->current_picture;
 679     emms_c();
 680
 681 #ifdef CONFIG_LIBXVID
 682     if((s->flags&CODEC_FLAG_PASS2) && s->avctx->rc_strategy == FF_RC_STRATEGY_XVID)
 683         return ff_xvid_rate_estimate_qscale(s, dry_run);
 684 #endif
 685
 686     get_qminmax(&qmin, &qmax, s, pict_type);
 687
 688     fps= 1/av_q2d(s->avctx->time_base);
 689 //printf("input_pic_num:%d pic_num:%d frame_rate:%d\n", s->input_picture_number, s->picture_number, s->frame_rate);
 690         /* update predictors */
 691     if(picture_number>2 && !dry_run){
 692         const int last_var= s->last_pict_type == FF_I_TYPE ? rcc->last_mb_var_sum : rcc->last_mc_mb_var_sum;
 693         update_predictor(&rcc->pred[s->last_pict_type], rcc->last_qscale, sqrt(last_var), s->frame_bits);
 694     }
 695
 696     if(s->flags&CODEC_FLAG_PASS2){
 697         assert(picture_number>=0);
 698         assert(picture_number<rcc->num_entries);
 699         rce= &rcc->entry[picture_number];
 700         wanted_bits= rce->expected_bits;
 701     }else{
 702         Picture *dts_pic;
 703         rce= &local_rce;
 704
 705         //FIXME add a dts field to AVFrame and ensure its set and use it here instead of reordering
 706         //but the reordering is simpler for now until h.264 b pyramid must be handeld
 707         if(s->pict_type == FF_B_TYPE || s->low_delay)
 708             dts_pic= s->current_picture_ptr;
 709         else
 710             dts_pic= s->last_picture_ptr;
 711
 712 //if(dts_pic)
 713 //            av_log(NULL, AV_LOG_ERROR, "%Ld %Ld %Ld %d\n", s->current_picture_ptr->pts, s->user_specified_pts, dts_pic->pts, picture_number);
 714
 715         if(!dts_pic || dts_pic->pts == AV_NOPTS_VALUE)
 716             wanted_bits= (uint64_t)(s->bit_rate*(double)picture_number/fps);
 717         else
 718             wanted_bits= (uint64_t)(s->bit_rate*(double)dts_pic->pts/fps);
 719     }
 720
 721     diff= s->total_bits - wanted_bits;
 722     br_compensation= (a->bit_rate_tolerance - diff)/a->bit_rate_tolerance;
 723     if(br_compensation<=0.0) br_compensation=0.001;
 724
 725     var= pict_type == FF_I_TYPE ? pic->mb_var_sum : pic->mc_mb_var_sum;
 726
 727     short_term_q = 0; /* avoid warning */
 728     if(s->flags&CODEC_FLAG_PASS2){
 729         if(pict_type!=FF_I_TYPE)
 730             assert(pict_type == rce->new_pict_type);
 731
 732         q= rce->new_qscale / br_compensation;
 733 //printf("%f %f %f last:%d var:%d type:%d//\n", q, rce->new_qscale, br_compensation, s->frame_bits, var, pict_type);
 734     }else{
 735         rce->pict_type=
 736         rce->new_pict_type= pict_type;
 737         rce->mc_mb_var_sum= pic->mc_mb_var_sum;
 738         rce->mb_var_sum   = pic->   mb_var_sum;
 739         rce->qscale   = FF_QP2LAMBDA * 2;
 740         rce->f_code   = s->f_code;
 741         rce->b_code   = s->b_code;
 742         rce->misc_bits= 1;
 743
 744         bits= predict_size(&rcc->pred[pict_type], rce->qscale, sqrt(var));
 745         if(pict_type== FF_I_TYPE){
 746             rce->i_count   = s->mb_num;
 747             rce->i_tex_bits= bits;
 748             rce->p_tex_bits= 0;
 749             rce->mv_bits= 0;
 750         }else{
 751             rce->i_count   = 0; //FIXME we do know this approx
 752             rce->i_tex_bits= 0;
 753             rce->p_tex_bits= bits*0.9;
 754
 755             rce->mv_bits= bits*0.1;
 756         }
 757         rcc->i_cplx_sum [pict_type] += rce->i_tex_bits*rce->qscale;
 758         rcc->p_cplx_sum [pict_type] += rce->p_tex_bits*rce->qscale;
 759         rcc->mv_bits_sum[pict_type] += rce->mv_bits;
 760         rcc->frame_count[pict_type] ++;
 761
 762         bits= rce->i_tex_bits + rce->p_tex_bits;
 763         rate_factor= rcc->pass1_wanted_bits/rcc->pass1_rc_eq_output_sum * br_compensation;
 764
 765         q= get_qscale(s, rce, rate_factor, picture_number);
 766         if (q < 0)
 767             return -1;
 768
 769         assert(q>0.0);
 770 //printf("%f ", q);
 771         q= get_diff_limited_q(s, rce, q);
 772 //printf("%f ", q);
 773         assert(q>0.0);
 774
 775         if(pict_type==FF_P_TYPE || s->intra_only){ //FIXME type dependent blur like in 2-pass
 776             rcc->short_term_qsum*=a->qblur;
 777             rcc->short_term_qcount*=a->qblur;
 778
 779             rcc->short_term_qsum+= q;
 780             rcc->short_term_qcount++;
 781 //printf("%f ", q);
 782             q= short_term_q= rcc->short_term_qsum/rcc->short_term_qcount;
 783 //printf("%f ", q);
 784         }
 785         assert(q>0.0);
 786
 787         q= modify_qscale(s, rce, q, picture_number);
 788
 789         rcc->pass1_wanted_bits+= s->bit_rate/fps;
 790
 791         assert(q>0.0);
 792     }
 793
 794     if(s->avctx->debug&FF_DEBUG_RC){
 795         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",
 796         av_get_pict_type_char(pict_type), qmin, q, qmax, picture_number, (int)wanted_bits/1000, (int)s->total_bits/1000,
 797         br_compensation, short_term_q, s->frame_bits, pic->mb_var_sum, pic->mc_mb_var_sum, s->bit_rate/1000, (int)fps
 798         );
 799     }
 800
 801     if     (q<qmin) q=qmin;
 802     else if(q>qmax) q=qmax;
 803
 804     if(s->adaptive_quant)
 805         adaptive_quantization(s, q);
 806     else
 807         q= (int)(q + 0.5);
 808
 809     if(!dry_run){
 810         rcc->last_qscale= q;
 811         rcc->last_mc_mb_var_sum= pic->mc_mb_var_sum;
 812         rcc->last_mb_var_sum= pic->mb_var_sum;
 813     }
 814 #if 0
 815 {
 816     static int mvsum=0, texsum=0;
 817     mvsum += s->mv_bits;
 818     texsum += s->i_tex_bits + s->p_tex_bits;
 819     printf("%d %d//\n\n", mvsum, texsum);
 820 }
 821 #endif
 822     return q;
 823 }
 824
 825 //----------------------------------------------
 826 // 2-Pass code
 827
 828 static int init_pass2(MpegEncContext *s)
 829 {
 830     RateControlContext *rcc= &s->rc_context;
 831     AVCodecContext *a= s->avctx;
 832     int i, toobig;
 833     double fps= 1/av_q2d(s->avctx->time_base);
 834     double complexity[5]={0,0,0,0,0};   // aproximate bits at quant=1
 835     uint64_t const_bits[5]={0,0,0,0,0}; // quantizer independent bits
 836     uint64_t all_const_bits;
 837     uint64_t all_available_bits= (uint64_t)(s->bit_rate*(double)rcc->num_entries/fps);
 838     double rate_factor=0;
 839     double step;
 840     //int last_i_frame=-10000000;
 841     const int filter_size= (int)(a->qblur*4) | 1;
 842     double expected_bits;
 843     double *qscale, *blurred_qscale, qscale_sum;
 844
 845     /* find complexity & const_bits & decide the pict_types */
 846     for(i=0; i<rcc->num_entries; i++){
 847         RateControlEntry *rce= &rcc->entry[i];
 848
 849         rce->new_pict_type= rce->pict_type;
 850         rcc->i_cplx_sum [rce->pict_type] += rce->i_tex_bits*rce->qscale;
 851         rcc->p_cplx_sum [rce->pict_type] += rce->p_tex_bits*rce->qscale;
 852         rcc->mv_bits_sum[rce->pict_type] += rce->mv_bits;
 853         rcc->frame_count[rce->pict_type] ++;
 854
 855         complexity[rce->new_pict_type]+= (rce->i_tex_bits+ rce->p_tex_bits)*(double)rce->qscale;
 856         const_bits[rce->new_pict_type]+= rce->mv_bits + rce->misc_bits;
 857     }
 858     all_const_bits= const_bits[FF_I_TYPE] + const_bits[FF_P_TYPE] + const_bits[FF_B_TYPE];
 859
 860     if(all_available_bits < all_const_bits){
 861         av_log(s->avctx, AV_LOG_ERROR, "requested bitrate is too low\n");
 862         return -1;
 863     }
 864
 865     qscale= av_malloc(sizeof(double)*rcc->num_entries);
 866     blurred_qscale= av_malloc(sizeof(double)*rcc->num_entries);
 867     toobig = 0;
 868
 869     for(step=256*256; step>0.0000001; step*=0.5){
 870         expected_bits=0;
 871         rate_factor+= step;
 872
 873         rcc->buffer_index= s->avctx->rc_buffer_size/2;
 874
 875         /* find qscale */
 876         for(i=0; i<rcc->num_entries; i++){
 877             qscale[i]= get_qscale(s, &rcc->entry[i], rate_factor, i);
 878         }
 879         assert(filter_size%2==1);
 880
 881         /* fixed I/B QP relative to P mode */
 882         for(i=rcc->num_entries-1; i>=0; i--){
 883             RateControlEntry *rce= &rcc->entry[i];
 884
 885             qscale[i]= get_diff_limited_q(s, rce, qscale[i]);
 886         }
 887
 888         /* smooth curve */
 889         for(i=0; i<rcc->num_entries; i++){
 890             RateControlEntry *rce= &rcc->entry[i];
 891             const int pict_type= rce->new_pict_type;
 892             int j;
 893             double q=0.0, sum=0.0;
 894
 895             for(j=0; j<filter_size; j++){
 896                 int index= i+j-filter_size/2;
 897                 double d= index-i;
 898                 double coeff= a->qblur==0 ? 1.0 : exp(-d*d/(a->qblur * a->qblur));
 899
 900                 if(index < 0 || index >= rcc->num_entries) continue;
 901                 if(pict_type != rcc->entry[index].new_pict_type) continue;
 902                 q+= qscale[index] * coeff;
 903                 sum+= coeff;
 904             }
 905             blurred_qscale[i]= q/sum;
 906         }
 907
 908         /* find expected bits */
 909         for(i=0; i<rcc->num_entries; i++){
 910             RateControlEntry *rce= &rcc->entry[i];
 911             double bits;
 912             rce->new_qscale= modify_qscale(s, rce, blurred_qscale[i], i);
 913             bits= qp2bits(rce, rce->new_qscale) + rce->mv_bits + rce->misc_bits;
 914 //printf("%d %f\n", rce->new_bits, blurred_qscale[i]);
 915             bits += 8*ff_vbv_update(s, bits);
 916
 917             rce->expected_bits= expected_bits;
 918             expected_bits += bits;
 919         }
 920
 921         /*
 922         av_log(s->avctx, AV_LOG_INFO,
 923             "expected_bits: %f all_available_bits: %d rate_factor: %f\n",
 924             expected_bits, (int)all_available_bits, rate_factor);
 925         */
 926         if(expected_bits > all_available_bits) {
 927             rate_factor-= step;
 928             ++toobig;
 929         }
 930     }
 931     av_free(qscale);
 932     av_free(blurred_qscale);
 933
 934     /* check bitrate calculations and print info */
 935     qscale_sum = 0.0;
 936     for(i=0; i<rcc->num_entries; i++){
 937         /* av_log(s->avctx, AV_LOG_DEBUG, "[lavc rc] entry[%d].new_qscale = %.3f  qp = %.3f\n",
 938             i, rcc->entry[i].new_qscale, rcc->entry[i].new_qscale / FF_QP2LAMBDA); */
 939         qscale_sum += av_clip(rcc->entry[i].new_qscale / FF_QP2LAMBDA, s->avctx->qmin, s->avctx->qmax);
 940     }
 941     assert(toobig <= 40);
 942     av_log(s->avctx, AV_LOG_DEBUG,
 943         "[lavc rc] requested bitrate: %d bps  expected bitrate: %d bps\n",
 944         s->bit_rate,
 945         (int)(expected_bits / ((double)all_available_bits/s->bit_rate)));
 946     av_log(s->avctx, AV_LOG_DEBUG,
 947         "[lavc rc] estimated target average qp: %.3f\n",
 948         (float)qscale_sum / rcc->num_entries);
 949     if (toobig == 0) {
 950         av_log(s->avctx, AV_LOG_INFO,
 951             "[lavc rc] Using all of requested bitrate is not "
 952             "necessary for this video with these parameters.\n");
 953     } else if (toobig == 40) {
 954         av_log(s->avctx, AV_LOG_ERROR,
 955             "[lavc rc] Error: bitrate too low for this video "
 956             "with these parameters.\n");
 957         return -1;
 958     } else if (fabs(expected_bits/all_available_bits - 1.0) > 0.01) {
 959         av_log(s->avctx, AV_LOG_ERROR,
 960             "[lavc rc] Error: 2pass curve failed to converge\n");
 961         return -1;
 962     }
 963
 964     return 0;
 965 }