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 "libavutil/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->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);
  50 }
  51
  52 static double get_fps(AVCodecContext *avctx){
  53     return 1.0 / av_q2d(avctx->time_base) / FFMAX(avctx->ticks_per_frame, 1);
  54 }
  55
  56 static inline double qp2bits(RateControlEntry *rce, double qp){
  57     if(qp<=0.0){
  58         av_log(NULL, AV_LOG_ERROR, "qp<=0.0\n");
  59     }
  60     return rce->qscale * (double)(rce->i_tex_bits + rce->p_tex_bits+1)/ qp;
  61 }
  62
  63 static inline double bits2qp(RateControlEntry *rce, double bits){
  64     if(bits<0.9){
  65         av_log(NULL, AV_LOG_ERROR, "bits<0.9\n");
  66     }
  67     return rce->qscale * (double)(rce->i_tex_bits + rce->p_tex_bits+1)/ bits;
  68 }
  69
  70 int ff_rate_control_init(MpegEncContext *s)
  71 {
  72     RateControlContext *rcc= &s->rc_context;
  73     int i, res;
  74     static const char * const const_names[]={
  75         "PI",
  76         "E",
  77         "iTex",
  78         "pTex",
  79         "tex",
  80         "mv",
  81         "fCode",
  82         "iCount",
  83         "mcVar",
  84         "var",
  85         "isI",
  86         "isP",
  87         "isB",
  88         "avgQP",
  89         "qComp",
  90 /*        "lastIQP",
  91         "lastPQP",
  92         "lastBQP",
  93         "nextNonBQP",*/
  94         "avgIITex",
  95         "avgPITex",
  96         "avgPPTex",
  97         "avgBPTex",
  98         "avgTex",
  99         NULL
 100     };
 101     static double (* const func1[])(void *, double)={
 102         (void *)bits2qp,
 103         (void *)qp2bits,
 104         NULL
 105     };
 106     static const char * const func1_names[]={
 107         "bits2qp",
 108         "qp2bits",
 109         NULL
 110     };
 111     emms_c();
 112
 113     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);
 114     if (res < 0) {
 115         av_log(s->avctx, AV_LOG_ERROR, "Error parsing rc_eq \"%s\"\n", s->avctx->rc_eq);
 116         return res;
 117     }
 118
 119     for(i=0; i<5; i++){
 120         rcc->pred[i].coeff= FF_QP2LAMBDA * 7.0;
 121         rcc->pred[i].count= 1.0;
 122
 123         rcc->pred[i].decay= 0.4;
 124         rcc->i_cplx_sum [i]=
 125         rcc->p_cplx_sum [i]=
 126         rcc->mv_bits_sum[i]=
 127         rcc->qscale_sum [i]=
 128         rcc->frame_count[i]= 1; // 1 is better because of 1/0 and such
 129         rcc->last_qscale_for[i]=FF_QP2LAMBDA * 5;
 130     }
 131     rcc->buffer_index= s->avctx->rc_initial_buffer_occupancy;
 132     if (!rcc->buffer_index)
 133         rcc->buffer_index = s->avctx->rc_buffer_size * 3 / 4;
 134
 135     if(s->flags&CODEC_FLAG_PASS2){
 136         int i;
 137         char *p;
 138
 139         /* find number of pics */
 140         p= s->avctx->stats_in;
 141         for(i=-1; p; i++){
 142             p= strchr(p+1, ';');
 143         }
 144         i+= s->max_b_frames;
 145         if(i<=0 || i>=INT_MAX / sizeof(RateControlEntry))
 146             return -1;
 147         rcc->entry = av_mallocz(i*sizeof(RateControlEntry));
 148         rcc->num_entries= i;
 149
 150         /* init all to skipped p frames (with b frames we might have a not encoded frame at the end FIXME) */
 151         for(i=0; i<rcc->num_entries; i++){
 152             RateControlEntry *rce= &rcc->entry[i];
 153             rce->pict_type= rce->new_pict_type=AV_PICTURE_TYPE_P;
 154             rce->qscale= rce->new_qscale=FF_QP2LAMBDA * 2;
 155             rce->misc_bits= s->mb_num + 10;
 156             rce->mb_var_sum= s->mb_num*100;
 157         }
 158
 159         /* read stats */
 160         p= s->avctx->stats_in;
 161         for(i=0; i<rcc->num_entries - s->max_b_frames; i++){
 162             RateControlEntry *rce;
 163             int picture_number;
 164             int e;
 165             char *next;
 166
 167             next= strchr(p, ';');
 168             if(next){
 169                 (*next)=0; //sscanf in unbelievably slow on looong strings //FIXME copy / do not write
 170                 next++;
 171             }
 172             e= sscanf(p, " in:%d ", &picture_number);
 173
 174             assert(picture_number >= 0);
 175             assert(picture_number < rcc->num_entries);
 176             rce= &rcc->entry[picture_number];
 177
 178             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",
 179                    &rce->pict_type, &rce->qscale, &rce->i_tex_bits, &rce->p_tex_bits, &rce->mv_bits, &rce->misc_bits,
 180                    &rce->f_code, &rce->b_code, &rce->mc_mb_var_sum, &rce->mb_var_sum, &rce->i_count, &rce->skip_count, &rce->header_bits);
 181             if(e!=14){
 182                 av_log(s->avctx, AV_LOG_ERROR, "statistics are damaged at line %d, parser out=%d\n", i, e);
 183                 return -1;
 184             }
 185
 186             p= next;
 187         }
 188
 189         if(init_pass2(s) < 0) return -1;
 190
 191         //FIXME maybe move to end
 192         if((s->flags&CODEC_FLAG_PASS2) && s->avctx->rc_strategy == FF_RC_STRATEGY_XVID) {
 193 #if CONFIG_LIBXVID
 194             return ff_xvid_rate_control_init(s);
 195 #else
 196             av_log(s->avctx, AV_LOG_ERROR, "Xvid ratecontrol requires libavcodec compiled with Xvid support.\n");
 197             return -1;
 198 #endif
 199         }
 200     }
 201
 202     if(!(s->flags&CODEC_FLAG_PASS2)){
 203
 204         rcc->short_term_qsum=0.001;
 205         rcc->short_term_qcount=0.001;
 206
 207         rcc->pass1_rc_eq_output_sum= 0.001;
 208         rcc->pass1_wanted_bits=0.001;
 209
 210         if(s->avctx->qblur > 1.0){
 211             av_log(s->avctx, AV_LOG_ERROR, "qblur too large\n");
 212             return -1;
 213         }
 214         /* init stuff with the user specified complexity */
 215         if(s->avctx->rc_initial_cplx){
 216             for(i=0; i<60*30; i++){
 217                 double bits= s->avctx->rc_initial_cplx * (i/10000.0 + 1.0)*s->mb_num;
 218                 RateControlEntry rce;
 219
 220                 if     (i%((s->gop_size+3)/4)==0) rce.pict_type= AV_PICTURE_TYPE_I;
 221                 else if(i%(s->max_b_frames+1))    rce.pict_type= AV_PICTURE_TYPE_B;
 222                 else                              rce.pict_type= AV_PICTURE_TYPE_P;
 223
 224                 rce.new_pict_type= rce.pict_type;
 225                 rce.mc_mb_var_sum= bits*s->mb_num/100000;
 226                 rce.mb_var_sum   = s->mb_num;
 227                 rce.qscale   = FF_QP2LAMBDA * 2;
 228                 rce.f_code   = 2;
 229                 rce.b_code   = 1;
 230                 rce.misc_bits= 1;
 231
 232                 if(s->pict_type== AV_PICTURE_TYPE_I){
 233                     rce.i_count   = s->mb_num;
 234                     rce.i_tex_bits= bits;
 235                     rce.p_tex_bits= 0;
 236                     rce.mv_bits= 0;
 237                 }else{
 238                     rce.i_count   = 0; //FIXME we do know this approx
 239                     rce.i_tex_bits= 0;
 240                     rce.p_tex_bits= bits*0.9;
 241                     rce.mv_bits= bits*0.1;
 242                 }
 243                 rcc->i_cplx_sum [rce.pict_type] += rce.i_tex_bits*rce.qscale;
 244                 rcc->p_cplx_sum [rce.pict_type] += rce.p_tex_bits*rce.qscale;
 245                 rcc->mv_bits_sum[rce.pict_type] += rce.mv_bits;
 246                 rcc->frame_count[rce.pict_type] ++;
 247
 248                 get_qscale(s, &rce, rcc->pass1_wanted_bits/rcc->pass1_rc_eq_output_sum, i);
 249                 rcc->pass1_wanted_bits+= s->bit_rate/get_fps(s); //FIXME misbehaves a little for variable fps
 250             }
 251         }
 252
 253     }
 254
 255     return 0;
 256 }
 257
 258 void ff_rate_control_uninit(MpegEncContext *s)
 259 {
 260     RateControlContext *rcc= &s->rc_context;
 261     emms_c();
 262
 263     av_expr_free(rcc->rc_eq_eval);
 264     av_freep(&rcc->entry);
 265
 266 #if CONFIG_LIBXVID
 267     if((s->flags&CODEC_FLAG_PASS2) && s->avctx->rc_strategy == FF_RC_STRATEGY_XVID)
 268         ff_xvid_rate_control_uninit(s);
 269 #endif
 270 }
 271
 272 int ff_vbv_update(MpegEncContext *s, int frame_size){
 273     RateControlContext *rcc= &s->rc_context;
 274     const double fps= get_fps(s->avctx);
 275     const int buffer_size= s->avctx->rc_buffer_size;
 276     const double min_rate= s->avctx->rc_min_rate/fps;
 277     const double max_rate= s->avctx->rc_max_rate/fps;
 278
 279 //printf("%d %f %d %f %f\n", buffer_size, rcc->buffer_index, frame_size, min_rate, max_rate);
 280     if(buffer_size){
 281         int left;
 282
 283         rcc->buffer_index-= frame_size;
 284         if(rcc->buffer_index < 0){
 285             av_log(s->avctx, AV_LOG_ERROR, "rc buffer underflow\n");
 286             rcc->buffer_index= 0;
 287         }
 288
 289         left= buffer_size - rcc->buffer_index - 1;
 290         rcc->buffer_index += av_clip(left, min_rate, max_rate);
 291
 292         if(rcc->buffer_index > buffer_size){
 293             int stuffing= ceil((rcc->buffer_index - buffer_size)/8);
 294
 295             if(stuffing < 4 && s->codec_id == CODEC_ID_MPEG4)
 296                 stuffing=4;
 297             rcc->buffer_index -= 8*stuffing;
 298
 299             if(s->avctx->debug & FF_DEBUG_RC)
 300                 av_log(s->avctx, AV_LOG_DEBUG, "stuffing %d bytes\n", stuffing);
 301
 302             return stuffing;
 303         }
 304     }
 305     return 0;
 306 }
 307
 308 /**
 309  * Modify the bitrate curve from pass1 for one frame.
 310  */
 311 static double get_qscale(MpegEncContext *s, RateControlEntry *rce, double rate_factor, int frame_num){
 312     RateControlContext *rcc= &s->rc_context;
 313     AVCodecContext *a= s->avctx;
 314     double q, bits;
 315     const int pict_type= rce->new_pict_type;
 316     const double mb_num= s->mb_num;
 317     int i;
 318
 319     double const_values[]={
 320         M_PI,
 321         M_E,
 322         rce->i_tex_bits*rce->qscale,
 323         rce->p_tex_bits*rce->qscale,
 324         (rce->i_tex_bits + rce->p_tex_bits)*(double)rce->qscale,
 325         rce->mv_bits/mb_num,
 326         rce->pict_type == AV_PICTURE_TYPE_B ? (rce->f_code + rce->b_code)*0.5 : rce->f_code,
 327         rce->i_count/mb_num,
 328         rce->mc_mb_var_sum/mb_num,
 329         rce->mb_var_sum/mb_num,
 330         rce->pict_type == AV_PICTURE_TYPE_I,
 331         rce->pict_type == AV_PICTURE_TYPE_P,
 332         rce->pict_type == AV_PICTURE_TYPE_B,
 333         rcc->qscale_sum[pict_type] / (double)rcc->frame_count[pict_type],
 334         a->qcompress,
 335 /*        rcc->last_qscale_for[AV_PICTURE_TYPE_I],
 336         rcc->last_qscale_for[AV_PICTURE_TYPE_P],
 337         rcc->last_qscale_for[AV_PICTURE_TYPE_B],
 338         rcc->next_non_b_qscale,*/
 339         rcc->i_cplx_sum[AV_PICTURE_TYPE_I] / (double)rcc->frame_count[AV_PICTURE_TYPE_I],
 340         rcc->i_cplx_sum[AV_PICTURE_TYPE_P] / (double)rcc->frame_count[AV_PICTURE_TYPE_P],
 341         rcc->p_cplx_sum[AV_PICTURE_TYPE_P] / (double)rcc->frame_count[AV_PICTURE_TYPE_P],
 342         rcc->p_cplx_sum[AV_PICTURE_TYPE_B] / (double)rcc->frame_count[AV_PICTURE_TYPE_B],
 343         (rcc->i_cplx_sum[pict_type] + rcc->p_cplx_sum[pict_type]) / (double)rcc->frame_count[pict_type],
 344         0
 345     };
 346
 347     bits = av_expr_eval(rcc->rc_eq_eval, const_values, rce);
 348     if (isnan(bits)) {
 349         av_log(s->avctx, AV_LOG_ERROR, "Error evaluating rc_eq \"%s\"\n", s->avctx->rc_eq);
 350         return -1;
 351     }
 352
 353     rcc->pass1_rc_eq_output_sum+= bits;
 354     bits*=rate_factor;
 355     if(bits<0.0) bits=0.0;
 356     bits+= 1.0; //avoid 1/0 issues
 357
 358     /* user override */
 359     for(i=0; i<s->avctx->rc_override_count; i++){
 360         RcOverride *rco= s->avctx->rc_override;
 361         if(rco[i].start_frame > frame_num) continue;
 362         if(rco[i].end_frame   < frame_num) continue;
 363
 364         if(rco[i].qscale)
 365             bits= qp2bits(rce, rco[i].qscale); //FIXME move at end to really force it?
 366         else
 367             bits*= rco[i].quality_factor;
 368     }
 369
 370     q= bits2qp(rce, bits);
 371
 372     /* I/B difference */
 373     if     (pict_type==AV_PICTURE_TYPE_I && s->avctx->i_quant_factor<0.0)
 374         q= -q*s->avctx->i_quant_factor + s->avctx->i_quant_offset;
 375     else if(pict_type==AV_PICTURE_TYPE_B && s->avctx->b_quant_factor<0.0)
 376         q= -q*s->avctx->b_quant_factor + s->avctx->b_quant_offset;
 377     if(q<1) q=1;
 378
 379     return q;
 380 }
 381
 382 static double get_diff_limited_q(MpegEncContext *s, RateControlEntry *rce, double q){
 383     RateControlContext *rcc= &s->rc_context;
 384     AVCodecContext *a= s->avctx;
 385     const int pict_type= rce->new_pict_type;
 386     const double last_p_q    = rcc->last_qscale_for[AV_PICTURE_TYPE_P];
 387     const double last_non_b_q= rcc->last_qscale_for[rcc->last_non_b_pict_type];
 388
 389     if     (pict_type==AV_PICTURE_TYPE_I && (a->i_quant_factor>0.0 || rcc->last_non_b_pict_type==AV_PICTURE_TYPE_P))
 390         q= last_p_q    *FFABS(a->i_quant_factor) + a->i_quant_offset;
 391     else if(pict_type==AV_PICTURE_TYPE_B && a->b_quant_factor>0.0)
 392         q= last_non_b_q*    a->b_quant_factor  + a->b_quant_offset;
 393     if(q<1) q=1;
 394
 395     /* last qscale / qdiff stuff */
 396     if(rcc->last_non_b_pict_type==pict_type || pict_type!=AV_PICTURE_TYPE_I){
 397         double last_q= rcc->last_qscale_for[pict_type];
 398         const int maxdiff= FF_QP2LAMBDA * a->max_qdiff;
 399
 400         if     (q > last_q + maxdiff) q= last_q + maxdiff;
 401         else if(q < last_q - maxdiff) q= last_q - maxdiff;
 402     }
 403
 404     rcc->last_qscale_for[pict_type]= q; //Note we cannot do that after blurring
 405
 406     if(pict_type!=AV_PICTURE_TYPE_B)
 407         rcc->last_non_b_pict_type= pict_type;
 408
 409     return q;
 410 }
 411
 412 /**
 413  * Get the qmin & qmax for pict_type.
 414  */
 415 static void get_qminmax(int *qmin_ret, int *qmax_ret, MpegEncContext *s, int pict_type){
 416     int qmin= s->avctx->lmin;
 417     int qmax= s->avctx->lmax;
 418
 419     assert(qmin <= qmax);
 420
 421     if(pict_type==AV_PICTURE_TYPE_B){
 422         qmin= (int)(qmin*FFABS(s->avctx->b_quant_factor)+s->avctx->b_quant_offset + 0.5);
 423         qmax= (int)(qmax*FFABS(s->avctx->b_quant_factor)+s->avctx->b_quant_offset + 0.5);
 424     }else if(pict_type==AV_PICTURE_TYPE_I){
 425         qmin= (int)(qmin*FFABS(s->avctx->i_quant_factor)+s->avctx->i_quant_offset + 0.5);
 426         qmax= (int)(qmax*FFABS(s->avctx->i_quant_factor)+s->avctx->i_quant_offset + 0.5);
 427     }
 428
 429     qmin= av_clip(qmin, 1, FF_LAMBDA_MAX);
 430     qmax= av_clip(qmax, 1, FF_LAMBDA_MAX);
 431
 432     if(qmax<qmin) qmax= qmin;
 433
 434     *qmin_ret= qmin;
 435     *qmax_ret= qmax;
 436 }
 437
 438 static double modify_qscale(MpegEncContext *s, RateControlEntry *rce, double q, int frame_num){
 439     RateControlContext *rcc= &s->rc_context;
 440     int qmin, qmax;
 441     const int pict_type= rce->new_pict_type;
 442     const double buffer_size= s->avctx->rc_buffer_size;
 443     const double fps= get_fps(s->avctx);
 444     const double min_rate= s->avctx->rc_min_rate / fps;
 445     const double max_rate= s->avctx->rc_max_rate / fps;
 446
 447     get_qminmax(&qmin, &qmax, s, pict_type);
 448
 449     /* modulation */
 450     if(s->avctx->rc_qmod_freq && frame_num%s->avctx->rc_qmod_freq==0 && pict_type==AV_PICTURE_TYPE_P)
 451         q*= s->avctx->rc_qmod_amp;
 452
 453 //printf("q:%f\n", q);
 454     /* buffer overflow/underflow protection */
 455     if(buffer_size){
 456         double expected_size= rcc->buffer_index;
 457         double q_limit;
 458
 459         if(min_rate){
 460             double d= 2*(buffer_size - expected_size)/buffer_size;
 461             if(d>1.0) d=1.0;
 462             else if(d<0.0001) d=0.0001;
 463             q*= pow(d, 1.0/s->avctx->rc_buffer_aggressivity);
 464
 465             q_limit= bits2qp(rce, FFMAX((min_rate - buffer_size + rcc->buffer_index) * s->avctx->rc_min_vbv_overflow_use, 1));
 466             if(q > q_limit){
 467                 if(s->avctx->debug&FF_DEBUG_RC){
 468                     av_log(s->avctx, AV_LOG_DEBUG, "limiting QP %f -> %f\n", q, q_limit);
 469                 }
 470                 q= q_limit;
 471             }
 472         }
 473
 474         if(max_rate){
 475             double d= 2*expected_size/buffer_size;
 476             if(d>1.0) d=1.0;
 477             else if(d<0.0001) d=0.0001;
 478             q/= pow(d, 1.0/s->avctx->rc_buffer_aggressivity);
 479
 480             q_limit= bits2qp(rce, FFMAX(rcc->buffer_index * s->avctx->rc_max_available_vbv_use, 1));
 481             if(q < q_limit){
 482                 if(s->avctx->debug&FF_DEBUG_RC){
 483                     av_log(s->avctx, AV_LOG_DEBUG, "limiting QP %f -> %f\n", q, q_limit);
 484                 }
 485                 q= q_limit;
 486             }
 487         }
 488     }
 489 //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);
 490     if(s->avctx->rc_qsquish==0.0 || qmin==qmax){
 491         if     (q<qmin) q=qmin;
 492         else if(q>qmax) q=qmax;
 493     }else{
 494         double min2= log(qmin);
 495         double max2= log(qmax);
 496
 497         q= log(q);
 498         q= (q - min2)/(max2-min2) - 0.5;
 499         q*= -4.0;
 500         q= 1.0/(1.0 + exp(q));
 501         q= q*(max2-min2) + min2;
 502
 503         q= exp(q);
 504     }
 505
 506     return q;
 507 }
 508
 509 //----------------------------------
 510 // 1 Pass Code
 511
 512 static double predict_size(Predictor *p, double q, double var)
 513 {
 514      return p->coeff*var / (q*p->count);
 515 }
 516
 517 /*
 518 static double predict_qp(Predictor *p, double size, double var)
 519 {
 520 //printf("coeff:%f, count:%f, var:%f, size:%f//\n", p->coeff, p->count, var, size);
 521      return p->coeff*var / (size*p->count);
 522 }
 523 */
 524
 525 static void update_predictor(Predictor *p, double q, double var, double size)
 526 {
 527     double new_coeff= size*q / (var + 1);
 528     if(var<10) return;
 529
 530     p->count*= p->decay;
 531     p->coeff*= p->decay;
 532     p->count++;
 533     p->coeff+= new_coeff;
 534 }
 535
 536 static void adaptive_quantization(MpegEncContext *s, double q){
 537     int i;
 538     const float lumi_masking= s->avctx->lumi_masking / (128.0*128.0);
 539     const float dark_masking= s->avctx->dark_masking / (128.0*128.0);
 540     const float temp_cplx_masking= s->avctx->temporal_cplx_masking;
 541     const float spatial_cplx_masking = s->avctx->spatial_cplx_masking;
 542     const float p_masking = s->avctx->p_masking;
 543     const float border_masking = s->avctx->border_masking;
 544     float bits_sum= 0.0;
 545     float cplx_sum= 0.0;
 546     float *cplx_tab = av_malloc(s->mb_num * sizeof(*cplx_tab));
 547     float *bits_tab = av_malloc(s->mb_num * sizeof(*bits_tab));
 548     const int qmin= s->avctx->mb_lmin;
 549     const int qmax= s->avctx->mb_lmax;
 550     Picture * const pic= &s->current_picture;
 551     const int mb_width = s->mb_width;
 552     const int mb_height = s->mb_height;
 553
 554     for(i=0; i<s->mb_num; i++){
 555         const int mb_xy= s->mb_index2xy[i];
 556         float temp_cplx= sqrt(pic->mc_mb_var[mb_xy]); //FIXME merge in pow()
 557         float spat_cplx= sqrt(pic->mb_var[mb_xy]);
 558         const int lumi= pic->mb_mean[mb_xy];
 559         float bits, cplx, factor;
 560         int mb_x = mb_xy % s->mb_stride;
 561         int mb_y = mb_xy / s->mb_stride;
 562         int mb_distance;
 563         float mb_factor = 0.0;
 564 #if 0
 565         if(spat_cplx < q/3) spat_cplx= q/3; //FIXME finetune
 566         if(temp_cplx < q/3) temp_cplx= q/3; //FIXME finetune
 567 #endif
 568         if(spat_cplx < 4) spat_cplx= 4; //FIXME finetune
 569         if(temp_cplx < 4) temp_cplx= 4; //FIXME finetune
 570
 571         if((s->mb_type[mb_xy]&CANDIDATE_MB_TYPE_INTRA)){//FIXME hq mode
 572             cplx= spat_cplx;
 573             factor= 1.0 + p_masking;
 574         }else{
 575             cplx= temp_cplx;
 576             factor= pow(temp_cplx, - temp_cplx_masking);
 577         }
 578         factor*=pow(spat_cplx, - spatial_cplx_masking);
 579
 580         if(lumi>127)
 581             factor*= (1.0 - (lumi-128)*(lumi-128)*lumi_masking);
 582         else
 583             factor*= (1.0 - (lumi-128)*(lumi-128)*dark_masking);
 584
 585         if(mb_x < mb_width/5){
 586             mb_distance = mb_width/5 - mb_x;
 587             mb_factor = (float)mb_distance / (float)(mb_width/5);
 588         }else if(mb_x > 4*mb_width/5){
 589             mb_distance = mb_x - 4*mb_width/5;
 590             mb_factor = (float)mb_distance / (float)(mb_width/5);
 591         }
 592         if(mb_y < mb_height/5){
 593             mb_distance = mb_height/5 - mb_y;
 594             mb_factor = FFMAX(mb_factor, (float)mb_distance / (float)(mb_height/5));
 595         }else if(mb_y > 4*mb_height/5){
 596             mb_distance = mb_y - 4*mb_height/5;
 597             mb_factor = FFMAX(mb_factor, (float)mb_distance / (float)(mb_height/5));
 598         }
 599
 600         factor*= 1.0 - border_masking*mb_factor;
 601
 602         if(factor<0.00001) factor= 0.00001;
 603
 604         bits= cplx*factor;
 605         cplx_sum+= cplx;
 606         bits_sum+= bits;
 607         cplx_tab[i]= cplx;
 608         bits_tab[i]= bits;
 609     }
 610
 611     /* handle qmin/qmax clipping */
 612     if(s->flags&CODEC_FLAG_NORMALIZE_AQP){
 613         float factor= bits_sum/cplx_sum;
 614         for(i=0; i<s->mb_num; i++){
 615             float newq= q*cplx_tab[i]/bits_tab[i];
 616             newq*= factor;
 617
 618             if     (newq > qmax){
 619                 bits_sum -= bits_tab[i];
 620                 cplx_sum -= cplx_tab[i]*q/qmax;
 621             }
 622             else if(newq < qmin){
 623                 bits_sum -= bits_tab[i];
 624                 cplx_sum -= cplx_tab[i]*q/qmin;
 625             }
 626         }
 627         if(bits_sum < 0.001) bits_sum= 0.001;
 628         if(cplx_sum < 0.001) cplx_sum= 0.001;
 629     }
 630
 631     for(i=0; i<s->mb_num; i++){
 632         const int mb_xy= s->mb_index2xy[i];
 633         float newq= q*cplx_tab[i]/bits_tab[i];
 634         int intq;
 635
 636         if(s->flags&CODEC_FLAG_NORMALIZE_AQP){
 637             newq*= bits_sum/cplx_sum;
 638         }
 639
 640         intq= (int)(newq + 0.5);
 641
 642         if     (intq > qmax) intq= qmax;
 643         else if(intq < qmin) intq= qmin;
 644 //if(i%s->mb_width==0) printf("\n");
 645 //printf("%2d%3d ", intq, ff_sqrt(s->mc_mb_var[i]));
 646         s->lambda_table[mb_xy]= intq;
 647     }
 648
 649     av_free(cplx_tab);
 650     av_free(bits_tab);
 651 }
 652
 653 void ff_get_2pass_fcode(MpegEncContext *s){
 654     RateControlContext *rcc= &s->rc_context;
 655     int picture_number= s->picture_number;
 656     RateControlEntry *rce;
 657
 658     rce= &rcc->entry[picture_number];
 659     s->f_code= rce->f_code;
 660     s->b_code= rce->b_code;
 661 }
 662
 663 //FIXME rd or at least approx for dquant
 664
 665 float ff_rate_estimate_qscale(MpegEncContext *s, int dry_run)
 666 {
 667     float q;
 668     int qmin, qmax;
 669     float br_compensation;
 670     double diff;
 671     double short_term_q;
 672     double fps;
 673     int picture_number= s->picture_number;
 674     int64_t wanted_bits;
 675     RateControlContext *rcc= &s->rc_context;
 676     AVCodecContext *a= s->avctx;
 677     RateControlEntry local_rce, *rce;
 678     double bits;
 679     double rate_factor;
 680     int var;
 681     const int pict_type= s->pict_type;
 682     Picture * const pic= &s->current_picture;
 683     emms_c();
 684
 685 #if CONFIG_LIBXVID
 686     if((s->flags&CODEC_FLAG_PASS2) && s->avctx->rc_strategy == FF_RC_STRATEGY_XVID)
 687         return ff_xvid_rate_estimate_qscale(s, dry_run);
 688 #endif
 689
 690     get_qminmax(&qmin, &qmax, s, pict_type);
 691
 692     fps= get_fps(s->avctx);
 693 //printf("input_pic_num:%d pic_num:%d frame_rate:%d\n", s->input_picture_number, s->picture_number, s->frame_rate);
 694         /* update predictors */
 695     if(picture_number>2 && !dry_run){
 696         const int last_var= s->last_pict_type == AV_PICTURE_TYPE_I ? rcc->last_mb_var_sum : rcc->last_mc_mb_var_sum;
 697         update_predictor(&rcc->pred[s->last_pict_type], rcc->last_qscale, sqrt(last_var), s->frame_bits);
 698     }
 699
 700     if(s->flags&CODEC_FLAG_PASS2){
 701         assert(picture_number>=0);
 702         assert(picture_number<rcc->num_entries);
 703         rce= &rcc->entry[picture_number];
 704         wanted_bits= rce->expected_bits;
 705     }else{
 706         Picture *dts_pic;
 707         rce= &local_rce;
 708
 709         //FIXME add a dts field to AVFrame and ensure its set and use it here instead of reordering
 710         //but the reordering is simpler for now until h.264 b pyramid must be handeld
 711         if(s->pict_type == AV_PICTURE_TYPE_B || s->low_delay)
 712             dts_pic= s->current_picture_ptr;
 713         else
 714             dts_pic= s->last_picture_ptr;
 715
 716 //if(dts_pic)
 717 //            av_log(NULL, AV_LOG_ERROR, "%"PRId64" %"PRId64" %"PRId64" %d\n", s->current_picture_ptr->pts, s->user_specified_pts, dts_pic->pts, picture_number);
 718
 719         if (!dts_pic || dts_pic->f.pts == AV_NOPTS_VALUE)
 720             wanted_bits= (uint64_t)(s->bit_rate*(double)picture_number/fps);
 721         else
 722             wanted_bits = (uint64_t)(s->bit_rate*(double)dts_pic->f.pts / fps);
 723     }
 724
 725     diff= s->total_bits - wanted_bits;
 726     br_compensation= (a->bit_rate_tolerance - diff)/a->bit_rate_tolerance;
 727     if(br_compensation<=0.0) br_compensation=0.001;
 728
 729     var= pict_type == AV_PICTURE_TYPE_I ? pic->mb_var_sum : pic->mc_mb_var_sum;
 730
 731     short_term_q = 0; /* avoid warning */
 732     if(s->flags&CODEC_FLAG_PASS2){
 733         if(pict_type!=AV_PICTURE_TYPE_I)
 734             assert(pict_type == rce->new_pict_type);
 735
 736         q= rce->new_qscale / br_compensation;
 737 //printf("%f %f %f last:%d var:%d type:%d//\n", q, rce->new_qscale, br_compensation, s->frame_bits, var, pict_type);
 738     }else{
 739         rce->pict_type=
 740         rce->new_pict_type= pict_type;
 741         rce->mc_mb_var_sum= pic->mc_mb_var_sum;
 742         rce->mb_var_sum   = pic->   mb_var_sum;
 743         rce->qscale   = FF_QP2LAMBDA * 2;
 744         rce->f_code   = s->f_code;
 745         rce->b_code   = s->b_code;
 746         rce->misc_bits= 1;
 747
 748         bits= predict_size(&rcc->pred[pict_type], rce->qscale, sqrt(var));
 749         if(pict_type== AV_PICTURE_TYPE_I){
 750             rce->i_count   = s->mb_num;
 751             rce->i_tex_bits= bits;
 752             rce->p_tex_bits= 0;
 753             rce->mv_bits= 0;
 754         }else{
 755             rce->i_count   = 0; //FIXME we do know this approx
 756             rce->i_tex_bits= 0;
 757             rce->p_tex_bits= bits*0.9;
 758
 759             rce->mv_bits= bits*0.1;
 760         }
 761         rcc->i_cplx_sum [pict_type] += rce->i_tex_bits*rce->qscale;
 762         rcc->p_cplx_sum [pict_type] += rce->p_tex_bits*rce->qscale;
 763         rcc->mv_bits_sum[pict_type] += rce->mv_bits;
 764         rcc->frame_count[pict_type] ++;
 765
 766         bits= rce->i_tex_bits + rce->p_tex_bits;
 767         rate_factor= rcc->pass1_wanted_bits/rcc->pass1_rc_eq_output_sum * br_compensation;
 768
 769         q= get_qscale(s, rce, rate_factor, picture_number);
 770         if (q < 0)
 771             return -1;
 772
 773         assert(q>0.0);
 774 //printf("%f ", q);
 775         q= get_diff_limited_q(s, rce, q);
 776 //printf("%f ", q);
 777         assert(q>0.0);
 778
 779         if(pict_type==AV_PICTURE_TYPE_P || s->intra_only){ //FIXME type dependent blur like in 2-pass
 780             rcc->short_term_qsum*=a->qblur;
 781             rcc->short_term_qcount*=a->qblur;
 782
 783             rcc->short_term_qsum+= q;
 784             rcc->short_term_qcount++;
 785 //printf("%f ", q);
 786             q= short_term_q= rcc->short_term_qsum/rcc->short_term_qcount;
 787 //printf("%f ", q);
 788         }
 789         assert(q>0.0);
 790
 791         q= modify_qscale(s, rce, q, picture_number);
 792
 793         rcc->pass1_wanted_bits+= s->bit_rate/fps;
 794
 795         assert(q>0.0);
 796     }
 797
 798     if(s->avctx->debug&FF_DEBUG_RC){
 799         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",
 800         av_get_picture_type_char(pict_type), qmin, q, qmax, picture_number, (int)wanted_bits/1000, (int)s->total_bits/1000,
 801         br_compensation, short_term_q, s->frame_bits, pic->mb_var_sum, pic->mc_mb_var_sum, s->bit_rate/1000, (int)fps
 802         );
 803     }
 804
 805     if     (q<qmin) q=qmin;
 806     else if(q>qmax) q=qmax;
 807
 808     if(s->adaptive_quant)
 809         adaptive_quantization(s, q);
 810     else
 811         q= (int)(q + 0.5);
 812
 813     if(!dry_run){
 814         rcc->last_qscale= q;
 815         rcc->last_mc_mb_var_sum= pic->mc_mb_var_sum;
 816         rcc->last_mb_var_sum= pic->mb_var_sum;
 817     }
 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= get_fps(s->avctx);
 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[AV_PICTURE_TYPE_I] + const_bits[AV_PICTURE_TYPE_P] + const_bits[AV_PICTURE_TYPE_B];
 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             RateControlEntry *rce= &rcc->entry[i];
 874             qscale[i]= get_qscale(s, &rcc->entry[i], rate_factor, i);
 875             rcc->last_qscale_for[rce->pict_type] = qscale[i];
 876         }
 877         assert(filter_size%2==1);
 878
 879         /* fixed I/B QP relative to P mode */
 880         for(i=FFMAX(0, rcc->num_entries-300); i<rcc->num_entries; i++){
 881             RateControlEntry *rce= &rcc->entry[i];
 882
 883             qscale[i]= get_diff_limited_q(s, rce, qscale[i]);
 884         }
 885
 886         for(i=rcc->num_entries-1; i>=0; i--){
 887             RateControlEntry *rce= &rcc->entry[i];
 888
 889             qscale[i]= get_diff_limited_q(s, rce, qscale[i]);
 890         }
 891
 892         /* smooth curve */
 893         for(i=0; i<rcc->num_entries; i++){
 894             RateControlEntry *rce= &rcc->entry[i];
 895             const int pict_type= rce->new_pict_type;
 896             int j;
 897             double q=0.0, sum=0.0;
 898
 899             for(j=0; j<filter_size; j++){
 900                 int index= i+j-filter_size/2;
 901                 double d= index-i;
 902                 double coeff= a->qblur==0 ? 1.0 : exp(-d*d/(a->qblur * a->qblur));
 903
 904                 if(index < 0 || index >= rcc->num_entries) continue;
 905                 if(pict_type != rcc->entry[index].new_pict_type) continue;
 906                 q+= qscale[index] * coeff;
 907                 sum+= coeff;
 908             }
 909             blurred_qscale[i]= q/sum;
 910         }
 911
 912         /* find expected bits */
 913         for(i=0; i<rcc->num_entries; i++){
 914             RateControlEntry *rce= &rcc->entry[i];
 915             double bits;
 916             rce->new_qscale= modify_qscale(s, rce, blurred_qscale[i], i);
 917             bits= qp2bits(rce, rce->new_qscale) + rce->mv_bits + rce->misc_bits;
 918 //printf("%d %f\n", rce->new_bits, blurred_qscale[i]);
 919             bits += 8*ff_vbv_update(s, bits);
 920
 921             rce->expected_bits= expected_bits;
 922             expected_bits += bits;
 923         }
 924
 925         /*
 926         av_log(s->avctx, AV_LOG_INFO,
 927             "expected_bits: %f all_available_bits: %d rate_factor: %f\n",
 928             expected_bits, (int)all_available_bits, rate_factor);
 929         */
 930         if(expected_bits > all_available_bits) {
 931             rate_factor-= step;
 932             ++toobig;
 933         }
 934     }
 935     av_free(qscale);
 936     av_free(blurred_qscale);
 937
 938     /* check bitrate calculations and print info */
 939     qscale_sum = 0.0;
 940     for(i=0; i<rcc->num_entries; i++){
 941         /* av_log(s->avctx, AV_LOG_DEBUG, "[lavc rc] entry[%d].new_qscale = %.3f  qp = %.3f\n",
 942             i, rcc->entry[i].new_qscale, rcc->entry[i].new_qscale / FF_QP2LAMBDA); */
 943         qscale_sum += av_clip(rcc->entry[i].new_qscale / FF_QP2LAMBDA, s->avctx->qmin, s->avctx->qmax);
 944     }
 945     assert(toobig <= 40);
 946     av_log(s->avctx, AV_LOG_DEBUG,
 947         "[lavc rc] requested bitrate: %d bps  expected bitrate: %d bps\n",
 948         s->bit_rate,
 949         (int)(expected_bits / ((double)all_available_bits/s->bit_rate)));
 950     av_log(s->avctx, AV_LOG_DEBUG,
 951         "[lavc rc] estimated target average qp: %.3f\n",
 952         (float)qscale_sum / rcc->num_entries);
 953     if (toobig == 0) {
 954         av_log(s->avctx, AV_LOG_INFO,
 955             "[lavc rc] Using all of requested bitrate is not "
 956             "necessary for this video with these parameters.\n");
 957     } else if (toobig == 40) {
 958         av_log(s->avctx, AV_LOG_ERROR,
 959             "[lavc rc] Error: bitrate too low for this video "
 960             "with these parameters.\n");
 961         return -1;
 962     } else if (fabs(expected_bits/all_available_bits - 1.0) > 0.01) {
 963         av_log(s->avctx, AV_LOG_ERROR,
 964             "[lavc rc] Error: 2pass curve failed to converge\n");
 965         return -1;
 966     }
 967
 968     return 0;
 969 }