git.sesse.net Git - ffmpeg/blob - 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
  25  * Rate control for video encoders.
  26  */
  27
  28 #include "libavutil/intmath.h"
  29 #include "avcodec.h"
  30 #include "dsputil.h"
  31 #include "ratecontrol.h"
  32 #include "mpegvideo.h"
  33 #include "eval.h"
  34
  35 #undef NDEBUG // Always check asserts, the speed effect is far too small to disable them.
  36 #include <assert.h>
  37
  38 #ifndef M_E
  39 #define M_E 2.718281828
  40 #endif
  41
  42 static int init_pass2(MpegEncContext *s);
  43 static double get_qscale(MpegEncContext *s, RateControlEntry *rce, double rate_factor, int frame_num);
  44
  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->display_picture_number, s->current_picture_ptr->coded_picture_number, s->pict_type,
  48             s->current_picture.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);
  50 }
  51
  52 static inline double qp2bits(RateControlEntry *rce, double qp){
  53     if(qp<=0.0){
  54         av_log(NULL, AV_LOG_ERROR, "qp<=0.0\n");
  55     }
  56     return rce->qscale * (double)(rce->i_tex_bits + rce->p_tex_bits+1)/ qp;
  57 }
  58
  59 static inline double bits2qp(RateControlEntry *rce, double bits){
  60     if(bits<0.9){
  61         av_log(NULL, AV_LOG_ERROR, "bits<0.9\n");
  62     }
  63     return rce->qscale * (double)(rce->i_tex_bits + rce->p_tex_bits+1)/ bits;
  64 }
  65
  66 int ff_rate_control_init(MpegEncContext *s)
  67 {
  68     RateControlContext *rcc= &s->rc_context;
  69     int i;
  70     const char *error = NULL;
  71     static const char * const const_names[]={
  72         "PI",
  73         "E",
  74         "iTex",
  75         "pTex",
  76         "tex",
  77         "mv",
  78         "fCode",
  79         "iCount",
  80         "mcVar",
  81         "var",
  82         "isI",
  83         "isP",
  84         "isB",
  85         "avgQP",
  86         "qComp",
  87 /*        "lastIQP",
  88         "lastPQP",
  89         "lastBQP",
  90         "nextNonBQP",*/
  91         "avgIITex",
  92         "avgPITex",
  93         "avgPPTex",
  94         "avgBPTex",
  95         "avgTex",
  96         NULL
  97     };
  98     static double (* const func1[])(void *, double)={
  99         (void *)bits2qp,
 100         (void *)qp2bits,
 101         NULL
 102     };
 103     static const char * const func1_names[]={
 104         "bits2qp",
 105         "qp2bits",
 106         NULL
 107     };
 108     emms_c();
 109
 110     rcc->rc_eq_eval = ff_parse_expr(s->avctx->rc_eq ? s->avctx->rc_eq : "tex^qComp", const_names, func1, func1_names, NULL, NULL, &error);
 111     if (!rcc->rc_eq_eval) {
 112         av_log(s->avctx, AV_LOG_ERROR, "Error parsing rc_eq \"%s\": %s\n", s->avctx->rc_eq, error? error : "");
 113         return -1;
 114     }
 115
 116     for(i=0; i<5; i++){
 117         rcc->pred[i].coeff= FF_QP2LAMBDA * 7.0;
 118         rcc->pred[i].count= 1.0;
 119
 120         rcc->pred[i].decay= 0.4;
 121         rcc->i_cplx_sum [i]=
 122         rcc->p_cplx_sum [i]=
 123         rcc->mv_bits_sum[i]=
 124         rcc->qscale_sum [i]=
 125         rcc->frame_count[i]= 1; // 1 is better because of 1/0 and such
 126         rcc->last_qscale_for[i]=FF_QP2LAMBDA * 5;
 127     }
 128     rcc->buffer_index= s->avctx->rc_initial_buffer_occupancy;
 129
 130     if(s->flags&CODEC_FLAG_PASS2){
 131         int i;
 132         char *p;
 133
 134         /* find number of pics */
 135         p= s->avctx->stats_in;
 136         for(i=-1; p; i++){
 137             p= strchr(p+1, ';');
 138         }
 139         i+= s->max_b_frames;
 140         if(i<=0 || i>=INT_MAX / sizeof(RateControlEntry))
 141             return -1;
 142         rcc->entry = av_mallocz(i*sizeof(RateControlEntry));
 143         rcc->num_entries= i;
 144
 145         /* init all to skipped p frames (with b frames we might have a not encoded frame at the end FIXME) */
 146         for(i=0; i<rcc->num_entries; i++){
 147             RateControlEntry *rce= &rcc->entry[i];
 148             rce->pict_type= rce->new_pict_type=FF_P_TYPE;
 149             rce->qscale= rce->new_qscale=FF_QP2LAMBDA * 2;
 150             rce->misc_bits= s->mb_num + 10;
 151             rce->mb_var_sum= s->mb_num*100;
 152         }
 153
 154         /* read stats */
 155         p= s->avctx->stats_in;
 156         for(i=0; i<rcc->num_entries - s->max_b_frames; i++){
 157             RateControlEntry *rce;
 158             int picture_number;
 159             int e;
 160             char *next;
 161
 162             next= strchr(p, ';');
 163             if(next){
 164                 (*next)=0; //sscanf in unbelievably slow on looong strings //FIXME copy / do not write
 165                 next++;
 166             }
 167             e= sscanf(p, " in:%d ", &picture_number);
 168
 169             assert(picture_number >= 0);
 170             assert(picture_number < rcc->num_entries);
 171             rce= &rcc->entry[picture_number];
 172
 173             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",
 174                    &rce->pict_type, &rce->qscale, &rce->i_tex_bits, &rce->p_tex_bits, &rce->mv_bits, &rce->misc_bits,
 175                    &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             if(e!=14){
 177                 av_log(s->avctx, AV_LOG_ERROR, "statistics are damaged at line %d, parser out=%d\n", i, e);
 178                 return -1;
 179             }
 180
 181             p= next;
 182         }
 183
 184         if(init_pass2(s) < 0) return -1;
 185
 186         //FIXME maybe move to end
 187         if((s->flags&CODEC_FLAG_PASS2) && s->avctx->rc_strategy == FF_RC_STRATEGY_XVID) {
 188 #if CONFIG_LIBXVID
 189             return ff_xvid_rate_control_init(s);
 190 #else
 191             av_log(s->avctx, AV_LOG_ERROR, "Xvid ratecontrol requires libavcodec compiled with Xvid support.\n");
 192             return -1;
 193 #endif
 194         }
 195     }
 196
 197     if(!(s->flags&CODEC_FLAG_PASS2)){
 198
 199         rcc->short_term_qsum=0.001;
 200         rcc->short_term_qcount=0.001;
 201
 202         rcc->pass1_rc_eq_output_sum= 0.001;
 203         rcc->pass1_wanted_bits=0.001;
 204
 205         if(s->avctx->qblur > 1.0){
 206             av_log(s->avctx, AV_LOG_ERROR, "qblur too large\n");
 207             return -1;
 208         }
 209         /* init stuff with the user specified complexity */
 210         if(s->avctx->rc_initial_cplx){
 211             for(i=0; i<60*30; i++){
 212                 double bits= s->avctx->rc_initial_cplx * (i/10000.0 + 1.0)*s->mb_num;
 213                 RateControlEntry rce;
 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                 get_qscale(s, &rce, rcc->pass1_wanted_bits/rcc->pass1_rc_eq_output_sum, i);
 244                 rcc->pass1_wanted_bits+= s->bit_rate/(1/av_q2d(s->avctx->time_base)); //FIXME misbehaves a little for variable fps
 245             }
 246         }
 247
 248     }
 249
 250     return 0;
 251 }
 252
 253 void ff_rate_control_uninit(MpegEncContext *s)
 254 {
 255     RateControlContext *rcc= &s->rc_context;
 256     emms_c();
 257
 258     ff_free_expr(rcc->rc_eq_eval);
 259     av_freep(&rcc->entry);
 260
 261 #if CONFIG_LIBXVID
 262     if((s->flags&CODEC_FLAG_PASS2) && s->avctx->rc_strategy == FF_RC_STRATEGY_XVID)
 263         ff_xvid_rate_control_uninit(s);
 264 #endif
 265 }
 266
 267 int ff_vbv_update(MpegEncContext *s, int frame_size){
 268     RateControlContext *rcc= &s->rc_context;
 269     const double fps= 1/av_q2d(s->avctx->time_base);
 270     const int buffer_size= s->avctx->rc_buffer_size;
 271     const double min_rate= s->avctx->rc_min_rate/fps;
 272     const double max_rate= s->avctx->rc_max_rate/fps;
 273
 274 //printf("%d %f %d %f %f\n", buffer_size, rcc->buffer_index, frame_size, min_rate, max_rate);
 275     if(buffer_size){
 276         int left;
 277
 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;
 282         }
 283
 284         left= buffer_size - rcc->buffer_index - 1;
 285         rcc->buffer_index += av_clip(left, min_rate, max_rate);
 286
 287         if(rcc->buffer_index > buffer_size){
 288             int stuffing= ceil((rcc->buffer_index - buffer_size)/8);
 289
 290             if(stuffing < 4 && s->codec_id == CODEC_ID_MPEG4)
 291                 stuffing=4;
 292             rcc->buffer_index -= 8*stuffing;
 293
 294             if(s->avctx->debug & FF_DEBUG_RC)
 295                 av_log(s->avctx, AV_LOG_DEBUG, "stuffing %d bytes\n", stuffing);
 296
 297             return stuffing;
 298         }
 299     }
 300     return 0;
 301 }
 302
 303 /**
 304  * modifies the bitrate curve from pass1 for one frame
 305  */
 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;
 309     double q, bits;
 310     const int pict_type= rce->new_pict_type;
 311     const double mb_num= s->mb_num;
 312     int i;
 313
 314     double const_values[]={
 315         M_PI,
 316         M_E,
 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,
 320         rce->mv_bits/mb_num,
 321         rce->pict_type == FF_B_TYPE ? (rce->f_code + rce->b_code)*0.5 : rce->f_code,
 322         rce->i_count/mb_num,
 323         rce->mc_mb_var_sum/mb_num,
 324         rce->mb_var_sum/mb_num,
 325         rce->pict_type == FF_I_TYPE,
 326         rce->pict_type == FF_P_TYPE,
 327         rce->pict_type == FF_B_TYPE,
 328         rcc->qscale_sum[pict_type] / (double)rcc->frame_count[pict_type],
 329         a->qcompress,
 330 /*        rcc->last_qscale_for[FF_I_TYPE],
 331         rcc->last_qscale_for[FF_P_TYPE],
 332         rcc->last_qscale_for[FF_B_TYPE],
 333         rcc->next_non_b_qscale,*/
 334         rcc->i_cplx_sum[FF_I_TYPE] / (double)rcc->frame_count[FF_I_TYPE],
 335         rcc->i_cplx_sum[FF_P_TYPE] / (double)rcc->frame_count[FF_P_TYPE],
 336         rcc->p_cplx_sum[FF_P_TYPE] / (double)rcc->frame_count[FF_P_TYPE],
 337         rcc->p_cplx_sum[FF_B_TYPE] / (double)rcc->frame_count[FF_B_TYPE],
 338         (rcc->i_cplx_sum[pict_type] + rcc->p_cplx_sum[pict_type]) / (double)rcc->frame_count[pict_type],
 339         0
 340     };
 341
 342     bits= ff_eval_expr(rcc->rc_eq_eval, const_values, rce);
 343     if (isnan(bits)) {
 344         av_log(s->avctx, AV_LOG_ERROR, "Error evaluating rc_eq \"%s\"\n", s->avctx->rc_eq);
 345         return -1;
 346     }
 347
 348     rcc->pass1_rc_eq_output_sum+= bits;
 349     bits*=rate_factor;
 350     if(bits<0.0) bits=0.0;
 351     bits+= 1.0; //avoid 1/0 issues
 352
 353     /* user override */
 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;
 358
 359         if(rco[i].qscale)
 360             bits= qp2bits(rce, rco[i].qscale); //FIXME move at end to really force it?
 361         else
 362             bits*= rco[i].quality_factor;
 363     }
 364
 365     q= bits2qp(rce, bits);
 366
 367     /* I/B difference */
 368     if     (pict_type==FF_I_TYPE && 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==FF_B_TYPE && s->avctx->b_quant_factor<0.0)
 371         q= -q*s->avctx->b_quant_factor + s->avctx->b_quant_offset;
 372     if(q<1) q=1;
 373
 374     return q;
 375 }
 376
 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[FF_P_TYPE];
 382     const double last_non_b_q= rcc->last_qscale_for[rcc->last_non_b_pict_type];
 383
 384     if     (pict_type==FF_I_TYPE && (a->i_quant_factor>0.0 || rcc->last_non_b_pict_type==FF_P_TYPE))
 385         q= last_p_q    *FFABS(a->i_quant_factor) + a->i_quant_offset;
 386     else if(pict_type==FF_B_TYPE && a->b_quant_factor>0.0)
 387         q= last_non_b_q*    a->b_quant_factor  + a->b_quant_offset;
 388     if(q<1) q=1;
 389
 390     /* last qscale / qdiff stuff */
 391     if(rcc->last_non_b_pict_type==pict_type || pict_type!=FF_I_TYPE){
 392         double last_q= rcc->last_qscale_for[pict_type];
 393         const int maxdiff= FF_QP2LAMBDA * a->max_qdiff;
 394
 395         if     (q > last_q + maxdiff) q= last_q + maxdiff;
 396         else if(q < last_q - maxdiff) q= last_q - maxdiff;
 397     }
 398
 399     rcc->last_qscale_for[pict_type]= q; //Note we cannot do that after blurring
 400
 401     if(pict_type!=FF_B_TYPE)
 402         rcc->last_non_b_pict_type= pict_type;
 403
 404     return q;
 405 }
 406
 407 /**
 408  * gets the qmin & qmax for pict_type
 409  */
 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;
 413
 414     assert(qmin <= qmax);
 415
 416     if(pict_type==FF_B_TYPE){
 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==FF_I_TYPE){
 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);
 422     }
 423
 424     qmin= av_clip(qmin, 1, FF_LAMBDA_MAX);
 425     qmax= av_clip(qmax, 1, FF_LAMBDA_MAX);
 426
 427     if(qmax<qmin) qmax= qmin;
 428
 429     *qmin_ret= qmin;
 430     *qmax_ret= qmax;
 431 }
 432
 433 static double modify_qscale(MpegEncContext *s, RateControlEntry *rce, double q, int frame_num){
 434     RateControlContext *rcc= &s->rc_context;
 435     int qmin, qmax;
 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;
 441
 442     get_qminmax(&qmin, &qmax, s, pict_type);
 443
 444     /* modulation */
 445     if(s->avctx->rc_qmod_freq && frame_num%s->avctx->rc_qmod_freq==0 && pict_type==FF_P_TYPE)
 446         q*= s->avctx->rc_qmod_amp;
 447
 448 //printf("q:%f\n", q);
 449     /* buffer overflow/underflow protection */
 450     if(buffer_size){
 451         double expected_size= rcc->buffer_index;
 452         double q_limit;
 453
 454         if(min_rate){
 455             double d= 2*(buffer_size - expected_size)/buffer_size;
 456             if(d>1.0) d=1.0;
 457             else if(d<0.0001) d=0.0001;
 458             q*= pow(d, 1.0/s->avctx->rc_buffer_aggressivity);
 459
 460             q_limit= bits2qp(rce, FFMAX((min_rate - buffer_size + rcc->buffer_index) * s->avctx->rc_min_vbv_overflow_use, 1));
 461             if(q > q_limit){
 462                 if(s->avctx->debug&FF_DEBUG_RC){
 463                     av_log(s->avctx, AV_LOG_DEBUG, "limiting QP %f -> %f\n", q, q_limit);
 464                 }
 465                 q= q_limit;
 466             }
 467         }
 468
 469         if(max_rate){
 470             double d= 2*expected_size/buffer_size;
 471             if(d>1.0) d=1.0;
 472             else if(d<0.0001) d=0.0001;
 473             q/= pow(d, 1.0/s->avctx->rc_buffer_aggressivity);
 474
 475             q_limit= bits2qp(rce, FFMAX(rcc->buffer_index * s->avctx->rc_max_available_vbv_use, 1));
 476             if(q < q_limit){
 477                 if(s->avctx->debug&FF_DEBUG_RC){
 478                     av_log(s->avctx, AV_LOG_DEBUG, "limiting QP %f -> %f\n", q, q_limit);
 479                 }
 480                 q= q_limit;
 481             }
 482         }
 483     }
 484 //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);
 485     if(s->avctx->rc_qsquish==0.0 || qmin==qmax){
 486         if     (q<qmin) q=qmin;
 487         else if(q>qmax) q=qmax;
 488     }else{
 489         double min2= log(qmin);
 490         double max2= log(qmax);
 491
 492         q= log(q);
 493         q= (q - min2)/(max2-min2) - 0.5;
 494         q*= -4.0;
 495         q= 1.0/(1.0 + exp(q));
 496         q= q*(max2-min2) + min2;
 497
 498         q= exp(q);
 499     }
 500
 501     return q;
 502 }
 503
 504 //----------------------------------
 505 // 1 Pass Code
 506
 507 static double predict_size(Predictor *p, double q, double var)
 508 {
 509      return p->coeff*var / (q*p->count);
 510 }
 511
 512 /*
 513 static double predict_qp(Predictor *p, double size, double var)
 514 {
 515 //printf("coeff:%f, count:%f, var:%f, size:%f//\n", p->coeff, p->count, var, size);
 516      return p->coeff*var / (size*p->count);
 517 }
 518 */
 519
 520 static void update_predictor(Predictor *p, double q, double var, double size)
 521 {
 522     double new_coeff= size*q / (var + 1);
 523     if(var<10) return;
 524
 525     p->count*= p->decay;
 526     p->coeff*= p->decay;
 527     p->count++;
 528     p->coeff+= new_coeff;
 529 }
 530
 531 static void adaptive_quantization(MpegEncContext *s, double q){
 532     int i;
 533     const float lumi_masking= s->avctx->lumi_masking / (128.0*128.0);
 534     const float dark_masking= s->avctx->dark_masking / (128.0*128.0);
 535     const float temp_cplx_masking= s->avctx->temporal_cplx_masking;
 536     const float spatial_cplx_masking = s->avctx->spatial_cplx_masking;
 537     const float p_masking = s->avctx->p_masking;
 538     const float border_masking = s->avctx->border_masking;
 539     float bits_sum= 0.0;
 540     float cplx_sum= 0.0;
 541     float cplx_tab[s->mb_num];
 542     float bits_tab[s->mb_num];
 543     const int qmin= s->avctx->mb_lmin;
 544     const int qmax= s->avctx->mb_lmax;
 545     Picture * const pic= &s->current_picture;
 546     const int mb_width = s->mb_width;
 547     const int mb_height = s->mb_height;
 548
 549     for(i=0; i<s->mb_num; i++){
 550         const int mb_xy= s->mb_index2xy[i];
 551         float temp_cplx= sqrt(pic->mc_mb_var[mb_xy]); //FIXME merge in pow()
 552         float spat_cplx= sqrt(pic->mb_var[mb_xy]);
 553         const int lumi= pic->mb_mean[mb_xy];
 554         float bits, cplx, factor;
 555         int mb_x = mb_xy % s->mb_stride;
 556         int mb_y = mb_xy / s->mb_stride;
 557         int mb_distance;
 558         float mb_factor = 0.0;
 559 #if 0
 560         if(spat_cplx < q/3) spat_cplx= q/3; //FIXME finetune
 561         if(temp_cplx < q/3) temp_cplx= q/3; //FIXME finetune
 562 #endif
 563         if(spat_cplx < 4) spat_cplx= 4; //FIXME finetune
 564         if(temp_cplx < 4) temp_cplx= 4; //FIXME finetune
 565
 566         if((s->mb_type[mb_xy]&CANDIDATE_MB_TYPE_INTRA)){//FIXME hq mode
 567             cplx= spat_cplx;
 568             factor= 1.0 + p_masking;
 569         }else{
 570             cplx= temp_cplx;
 571             factor= pow(temp_cplx, - temp_cplx_masking);
 572         }
 573         factor*=pow(spat_cplx, - spatial_cplx_masking);
 574
 575         if(lumi>127)
 576             factor*= (1.0 - (lumi-128)*(lumi-128)*lumi_masking);
 577         else
 578             factor*= (1.0 - (lumi-128)*(lumi-128)*dark_masking);
 579
 580         if(mb_x < mb_width/5){
 581             mb_distance = mb_width/5 - mb_x;
 582             mb_factor = (float)mb_distance / (float)(mb_width/5);
 583         }else if(mb_x > 4*mb_width/5){
 584             mb_distance = mb_x - 4*mb_width/5;
 585             mb_factor = (float)mb_distance / (float)(mb_width/5);
 586         }
 587         if(mb_y < mb_height/5){
 588             mb_distance = mb_height/5 - mb_y;
 589             mb_factor = FFMAX(mb_factor, (float)mb_distance / (float)(mb_height/5));
 590         }else if(mb_y > 4*mb_height/5){
 591             mb_distance = mb_y - 4*mb_height/5;
 592             mb_factor = FFMAX(mb_factor, (float)mb_distance / (float)(mb_height/5));
 593         }
 594
 595         factor*= 1.0 - border_masking*mb_factor;
 596
 597         if(factor<0.00001) factor= 0.00001;
 598
 599         bits= cplx*factor;
 600         cplx_sum+= cplx;
 601         bits_sum+= bits;
 602         cplx_tab[i]= cplx;
 603         bits_tab[i]= bits;
 604     }
 605
 606     /* handle qmin/qmax clipping */
 607     if(s->flags&CODEC_FLAG_NORMALIZE_AQP){
 608         float factor= bits_sum/cplx_sum;
 609         for(i=0; i<s->mb_num; i++){
 610             float newq= q*cplx_tab[i]/bits_tab[i];
 611             newq*= factor;
 612
 613             if     (newq > qmax){
 614                 bits_sum -= bits_tab[i];
 615                 cplx_sum -= cplx_tab[i]*q/qmax;
 616             }
 617             else if(newq < qmin){
 618                 bits_sum -= bits_tab[i];
 619                 cplx_sum -= cplx_tab[i]*q/qmin;
 620             }
 621         }
 622         if(bits_sum < 0.001) bits_sum= 0.001;
 623         if(cplx_sum < 0.001) cplx_sum= 0.001;
 624     }
 625
 626     for(i=0; i<s->mb_num; i++){
 627         const int mb_xy= s->mb_index2xy[i];
 628         float newq= q*cplx_tab[i]/bits_tab[i];
 629         int intq;
 630
 631         if(s->flags&CODEC_FLAG_NORMALIZE_AQP){
 632             newq*= bits_sum/cplx_sum;
 633         }
 634
 635         intq= (int)(newq + 0.5);
 636
 637         if     (intq > qmax) intq= qmax;
 638         else if(intq < qmin) intq= qmin;
 639 //if(i%s->mb_width==0) printf("\n");
 640 //printf("%2d%3d ", intq, ff_sqrt(s->mc_mb_var[i]));
 641         s->lambda_table[mb_xy]= intq;
 642     }
 643 }
 644
 645 void ff_get_2pass_fcode(MpegEncContext *s){
 646     RateControlContext *rcc= &s->rc_context;
 647     int picture_number= s->picture_number;
 648     RateControlEntry *rce;
 649
 650     rce= &rcc->entry[picture_number];
 651     s->f_code= rce->f_code;
 652     s->b_code= rce->b_code;
 653 }
 654
 655 //FIXME rd or at least approx for dquant
 656
 657 float ff_rate_estimate_qscale(MpegEncContext *s, int dry_run)
 658 {
 659     float q;
 660     int qmin, qmax;
 661     float br_compensation;
 662     double diff;
 663     double short_term_q;
 664     double fps;
 665     int picture_number= s->picture_number;
 666     int64_t wanted_bits;
 667     RateControlContext *rcc= &s->rc_context;
 668     AVCodecContext *a= s->avctx;
 669     RateControlEntry local_rce, *rce;
 670     double bits;
 671     double rate_factor;
 672     int var;
 673     const int pict_type= s->pict_type;
 674     Picture * const pic= &s->current_picture;
 675     emms_c();
 676
 677 #if CONFIG_LIBXVID
 678     if((s->flags&CODEC_FLAG_PASS2) && s->avctx->rc_strategy == FF_RC_STRATEGY_XVID)
 679         return ff_xvid_rate_estimate_qscale(s, dry_run);
 680 #endif
 681
 682     get_qminmax(&qmin, &qmax, s, pict_type);
 683
 684     fps= 1/av_q2d(s->avctx->time_base);
 685 //printf("input_pic_num:%d pic_num:%d frame_rate:%d\n", s->input_picture_number, s->picture_number, s->frame_rate);
 686         /* update predictors */
 687     if(picture_number>2 && !dry_run){
 688         const int last_var= s->last_pict_type == FF_I_TYPE ? rcc->last_mb_var_sum : rcc->last_mc_mb_var_sum;
 689         update_predictor(&rcc->pred[s->last_pict_type], rcc->last_qscale, sqrt(last_var), s->frame_bits);
 690     }
 691
 692     if(s->flags&CODEC_FLAG_PASS2){
 693         assert(picture_number>=0);
 694         assert(picture_number<rcc->num_entries);
 695         rce= &rcc->entry[picture_number];
 696         wanted_bits= rce->expected_bits;
 697     }else{
 698         Picture *dts_pic;
 699         rce= &local_rce;
 700
 701         //FIXME add a dts field to AVFrame and ensure its set and use it here instead of reordering
 702         //but the reordering is simpler for now until h.264 b pyramid must be handeld
 703         if(s->pict_type == FF_B_TYPE || s->low_delay)
 704             dts_pic= s->current_picture_ptr;
 705         else
 706             dts_pic= s->last_picture_ptr;
 707
 708 //if(dts_pic)
 709 //            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);
 710
 711         if(!dts_pic || dts_pic->pts == AV_NOPTS_VALUE)
 712             wanted_bits= (uint64_t)(s->bit_rate*(double)picture_number/fps);
 713         else
 714             wanted_bits= (uint64_t)(s->bit_rate*(double)dts_pic->pts/fps);
 715     }
 716
 717     diff= s->total_bits - wanted_bits;
 718     br_compensation= (a->bit_rate_tolerance - diff)/a->bit_rate_tolerance;
 719     if(br_compensation<=0.0) br_compensation=0.001;
 720
 721     var= pict_type == FF_I_TYPE ? pic->mb_var_sum : pic->mc_mb_var_sum;
 722
 723     short_term_q = 0; /* avoid warning */
 724     if(s->flags&CODEC_FLAG_PASS2){
 725         if(pict_type!=FF_I_TYPE)
 726             assert(pict_type == rce->new_pict_type);
 727
 728         q= rce->new_qscale / br_compensation;
 729 //printf("%f %f %f last:%d var:%d type:%d//\n", q, rce->new_qscale, br_compensation, s->frame_bits, var, pict_type);
 730     }else{
 731         rce->pict_type=
 732         rce->new_pict_type= pict_type;
 733         rce->mc_mb_var_sum= pic->mc_mb_var_sum;
 734         rce->mb_var_sum   = pic->   mb_var_sum;
 735         rce->qscale   = FF_QP2LAMBDA * 2;
 736         rce->f_code   = s->f_code;
 737         rce->b_code   = s->b_code;
 738         rce->misc_bits= 1;
 739
 740         bits= predict_size(&rcc->pred[pict_type], rce->qscale, sqrt(var));
 741         if(pict_type== FF_I_TYPE){
 742             rce->i_count   = s->mb_num;
 743             rce->i_tex_bits= bits;
 744             rce->p_tex_bits= 0;
 745             rce->mv_bits= 0;
 746         }else{
 747             rce->i_count   = 0; //FIXME we do know this approx
 748             rce->i_tex_bits= 0;
 749             rce->p_tex_bits= bits*0.9;
 750
 751             rce->mv_bits= bits*0.1;
 752         }
 753         rcc->i_cplx_sum [pict_type] += rce->i_tex_bits*rce->qscale;
 754         rcc->p_cplx_sum [pict_type] += rce->p_tex_bits*rce->qscale;
 755         rcc->mv_bits_sum[pict_type] += rce->mv_bits;
 756         rcc->frame_count[pict_type] ++;
 757
 758         bits= rce->i_tex_bits + rce->p_tex_bits;
 759         rate_factor= rcc->pass1_wanted_bits/rcc->pass1_rc_eq_output_sum * br_compensation;
 760
 761         q= get_qscale(s, rce, rate_factor, picture_number);
 762         if (q < 0)
 763             return -1;
 764
 765         assert(q>0.0);
 766 //printf("%f ", q);
 767         q= get_diff_limited_q(s, rce, q);
 768 //printf("%f ", q);
 769         assert(q>0.0);
 770
 771         if(pict_type==FF_P_TYPE || s->intra_only){ //FIXME type dependent blur like in 2-pass
 772             rcc->short_term_qsum*=a->qblur;
 773             rcc->short_term_qcount*=a->qblur;
 774
 775             rcc->short_term_qsum+= q;
 776             rcc->short_term_qcount++;
 777 //printf("%f ", q);
 778             q= short_term_q= rcc->short_term_qsum/rcc->short_term_qcount;
 779 //printf("%f ", q);
 780         }
 781         assert(q>0.0);
 782
 783         q= modify_qscale(s, rce, q, picture_number);
 784
 785         rcc->pass1_wanted_bits+= s->bit_rate/fps;
 786
 787         assert(q>0.0);
 788     }
 789
 790     if(s->avctx->debug&FF_DEBUG_RC){
 791         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",
 792         av_get_pict_type_char(pict_type), qmin, q, qmax, picture_number, (int)wanted_bits/1000, (int)s->total_bits/1000,
 793         br_compensation, short_term_q, s->frame_bits, pic->mb_var_sum, pic->mc_mb_var_sum, s->bit_rate/1000, (int)fps
 794         );
 795     }
 796
 797     if     (q<qmin) q=qmin;
 798     else if(q>qmax) q=qmax;
 799
 800     if(s->adaptive_quant)
 801         adaptive_quantization(s, q);
 802     else
 803         q= (int)(q + 0.5);
 804
 805     if(!dry_run){
 806         rcc->last_qscale= q;
 807         rcc->last_mc_mb_var_sum= pic->mc_mb_var_sum;
 808         rcc->last_mb_var_sum= pic->mb_var_sum;
 809     }
 810 #if 0
 811 {
 812     static int mvsum=0, texsum=0;
 813     mvsum += s->mv_bits;
 814     texsum += s->i_tex_bits + s->p_tex_bits;
 815     printf("%d %d//\n\n", mvsum, texsum);
 816 }
 817 #endif
 818     return q;
 819 }
 820
 821 //----------------------------------------------
 822 // 2-Pass code
 823
 824 static int init_pass2(MpegEncContext *s)
 825 {
 826     RateControlContext *rcc= &s->rc_context;
 827     AVCodecContext *a= s->avctx;
 828     int i, toobig;
 829     double fps= 1/av_q2d(s->avctx->time_base);
 830     double complexity[5]={0,0,0,0,0};   // aproximate bits at quant=1
 831     uint64_t const_bits[5]={0,0,0,0,0}; // quantizer independent bits
 832     uint64_t all_const_bits;
 833     uint64_t all_available_bits= (uint64_t)(s->bit_rate*(double)rcc->num_entries/fps);
 834     double rate_factor=0;
 835     double step;
 836     //int last_i_frame=-10000000;
 837     const int filter_size= (int)(a->qblur*4) | 1;
 838     double expected_bits;
 839     double *qscale, *blurred_qscale, qscale_sum;
 840
 841     /* find complexity & const_bits & decide the pict_types */
 842     for(i=0; i<rcc->num_entries; i++){
 843         RateControlEntry *rce= &rcc->entry[i];
 844
 845         rce->new_pict_type= rce->pict_type;
 846         rcc->i_cplx_sum [rce->pict_type] += rce->i_tex_bits*rce->qscale;
 847         rcc->p_cplx_sum [rce->pict_type] += rce->p_tex_bits*rce->qscale;
 848         rcc->mv_bits_sum[rce->pict_type] += rce->mv_bits;
 849         rcc->frame_count[rce->pict_type] ++;
 850
 851         complexity[rce->new_pict_type]+= (rce->i_tex_bits+ rce->p_tex_bits)*(double)rce->qscale;
 852         const_bits[rce->new_pict_type]+= rce->mv_bits + rce->misc_bits;
 853     }
 854     all_const_bits= const_bits[FF_I_TYPE] + const_bits[FF_P_TYPE] + const_bits[FF_B_TYPE];
 855
 856     if(all_available_bits < all_const_bits){
 857         av_log(s->avctx, AV_LOG_ERROR, "requested bitrate is too low\n");
 858         return -1;
 859     }
 860
 861     qscale= av_malloc(sizeof(double)*rcc->num_entries);
 862     blurred_qscale= av_malloc(sizeof(double)*rcc->num_entries);
 863     toobig = 0;
 864
 865     for(step=256*256; step>0.0000001; step*=0.5){
 866         expected_bits=0;
 867         rate_factor+= step;
 868
 869         rcc->buffer_index= s->avctx->rc_buffer_size/2;
 870
 871         /* find qscale */
 872         for(i=0; i<rcc->num_entries; i++){
 873             qscale[i]= get_qscale(s, &rcc->entry[i], rate_factor, i);
 874         }
 875         assert(filter_size%2==1);
 876
 877         /* fixed I/B QP relative to P mode */
 878         for(i=rcc->num_entries-1; i>=0; i--){
 879             RateControlEntry *rce= &rcc->entry[i];
 880
 881             qscale[i]= get_diff_limited_q(s, rce, qscale[i]);
 882         }
 883
 884         /* smooth curve */
 885         for(i=0; i<rcc->num_entries; i++){
 886             RateControlEntry *rce= &rcc->entry[i];
 887             const int pict_type= rce->new_pict_type;
 888             int j;
 889             double q=0.0, sum=0.0;
 890
 891             for(j=0; j<filter_size; j++){
 892                 int index= i+j-filter_size/2;
 893                 double d= index-i;
 894                 double coeff= a->qblur==0 ? 1.0 : exp(-d*d/(a->qblur * a->qblur));
 895
 896                 if(index < 0 || index >= rcc->num_entries) continue;
 897                 if(pict_type != rcc->entry[index].new_pict_type) continue;
 898                 q+= qscale[index] * coeff;
 899                 sum+= coeff;
 900             }
 901             blurred_qscale[i]= q/sum;
 902         }
 903
 904         /* find expected bits */
 905         for(i=0; i<rcc->num_entries; i++){
 906             RateControlEntry *rce= &rcc->entry[i];
 907             double bits;
 908             rce->new_qscale= modify_qscale(s, rce, blurred_qscale[i], i);
 909             bits= qp2bits(rce, rce->new_qscale) + rce->mv_bits + rce->misc_bits;
 910 //printf("%d %f\n", rce->new_bits, blurred_qscale[i]);
 911             bits += 8*ff_vbv_update(s, bits);
 912
 913             rce->expected_bits= expected_bits;
 914             expected_bits += bits;
 915         }
 916
 917         /*
 918         av_log(s->avctx, AV_LOG_INFO,
 919             "expected_bits: %f all_available_bits: %d rate_factor: %f\n",
 920             expected_bits, (int)all_available_bits, rate_factor);
 921         */
 922         if(expected_bits > all_available_bits) {
 923             rate_factor-= step;
 924             ++toobig;
 925         }
 926     }
 927     av_free(qscale);
 928     av_free(blurred_qscale);
 929
 930     /* check bitrate calculations and print info */
 931     qscale_sum = 0.0;
 932     for(i=0; i<rcc->num_entries; i++){
 933         /* av_log(s->avctx, AV_LOG_DEBUG, "[lavc rc] entry[%d].new_qscale = %.3f  qp = %.3f\n",
 934             i, rcc->entry[i].new_qscale, rcc->entry[i].new_qscale / FF_QP2LAMBDA); */
 935         qscale_sum += av_clip(rcc->entry[i].new_qscale / FF_QP2LAMBDA, s->avctx->qmin, s->avctx->qmax);
 936     }
 937     assert(toobig <= 40);
 938     av_log(s->avctx, AV_LOG_DEBUG,
 939         "[lavc rc] requested bitrate: %d bps  expected bitrate: %d bps\n",
 940         s->bit_rate,
 941         (int)(expected_bits / ((double)all_available_bits/s->bit_rate)));
 942     av_log(s->avctx, AV_LOG_DEBUG,
 943         "[lavc rc] estimated target average qp: %.3f\n",
 944         (float)qscale_sum / rcc->num_entries);
 945     if (toobig == 0) {
 946         av_log(s->avctx, AV_LOG_INFO,
 947             "[lavc rc] Using all of requested bitrate is not "
 948             "necessary for this video with these parameters.\n");
 949     } else if (toobig == 40) {
 950         av_log(s->avctx, AV_LOG_ERROR,
 951             "[lavc rc] Error: bitrate too low for this video "
 952             "with these parameters.\n");
 953         return -1;
 954     } else if (fabs(expected_bits/all_available_bits - 1.0) > 0.01) {
 955         av_log(s->avctx, AV_LOG_ERROR,
 956             "[lavc rc] Error: 2pass curve failed to converge\n");
 957         return -1;
 958     }
 959
 960     return 0;
 961 }