/*

  * Rate control for video encoders
  *

  * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>

  *

  * This file is part of FFmpeg.
  *
  * FFmpeg is free software; you can redistribute it and/or

  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either

  * version 2.1 of the License, or (at your option) any later version.

  *

  * FFmpeg is distributed in the hope that it will be useful,

  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public

  * License along with FFmpeg; if not, write to the Free Software

  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

  */

 
 /**

  * @file

  * Rate control for video encoders.

  */

 #include "avcodec.h"

 #include "ratecontrol.h"

 #include "mpegvideo.h"

 #include "libavutil/eval.h"

 #undef NDEBUG // Always check asserts, the speed effect is far too small to disable them.

 #include <assert.h>

 #ifndef M_E
 #define M_E 2.718281828
 #endif
 

 static int init_pass2(MpegEncContext *s);

 static double get_qscale(MpegEncContext *s, RateControlEntry *rce,
                          double rate_factor, int frame_num);

 void ff_write_pass1_stats(MpegEncContext *s)
 {
     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",
              s->current_picture_ptr->f.display_picture_number,
              s->current_picture_ptr->f.coded_picture_number,
              s->pict_type,
              s->current_picture.f.quality,
              s->i_tex_bits,
              s->p_tex_bits,
              s->mv_bits,
              s->misc_bits,
              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);

 }
 

 static double get_fps(AVCodecContext *avctx)
 {

     return 1.0 / av_q2d(avctx->time_base) / FFMAX(avctx->ticks_per_frame, 1);
 }
 

 static inline double qp2bits(RateControlEntry *rce, double qp)
 {
     if (qp <= 0.0) {

         av_log(NULL, AV_LOG_ERROR, "qp<=0.0\n");
     }

     return rce->qscale * (double)(rce->i_tex_bits + rce->p_tex_bits + 1) / qp;

 }
 

 static inline double bits2qp(RateControlEntry *rce, double bits)
 {
     if (bits < 0.9) {

         av_log(NULL, AV_LOG_ERROR, "bits<0.9\n");
     }

     return rce->qscale * (double)(rce->i_tex_bits + rce->p_tex_bits + 1) / bits;

 }
 

 int ff_rate_control_init(MpegEncContext *s)
 {

     RateControlContext *rcc = &s->rc_context;

     int i, res;

     static const char * const const_names[] = {

         "PI",
         "E",
         "iTex",
         "pTex",
         "tex",
         "mv",
         "fCode",
         "iCount",
         "mcVar",
         "var",
         "isI",
         "isP",
         "isB",
         "avgQP",
         "qComp",

 #if 0
         "lastIQP",

         "lastPQP",
         "lastBQP",

         "nextNonBQP",
 #endif

         "avgIITex",
         "avgPITex",
         "avgPPTex",
         "avgBPTex",
         "avgTex",
         NULL
     };

     static double (* const func1[])(void *, double) = {

         (void *)bits2qp,
         (void *)qp2bits,
         NULL
     };

     static const char * const func1_names[] = {

         "bits2qp",
         "qp2bits",
         NULL
     };

     emms_c();
 

     if (!s->avctx->rc_max_available_vbv_use && s->avctx->rc_buffer_size) {
         if (s->avctx->rc_max_rate) {

             s->avctx->rc_max_available_vbv_use = av_clipf(s->avctx->rc_max_rate/(s->avctx->rc_buffer_size*get_fps(s->avctx)), 1.0/3, 1.0);

         } else
             s->avctx->rc_max_available_vbv_use = 1.0;
     }
 

     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);

     if (res < 0) {

         av_log(s->avctx, AV_LOG_ERROR, "Error parsing rc_eq \"%s\"\n", s->avctx->rc_eq);

         return res;

     }
 

     for (i = 0; i < 5; i++) {
         rcc->pred[i].coeff = FF_QP2LAMBDA * 7.0;
         rcc->pred[i].count = 1.0;
         rcc->pred[i].decay = 0.4;
 
         rcc->i_cplx_sum [i] =
         rcc->p_cplx_sum [i] =
         rcc->mv_bits_sum[i] =
         rcc->qscale_sum [i] =
         rcc->frame_count[i] = 1; // 1 is better because of 1/0 and such
 
         rcc->last_qscale_for[i] = FF_QP2LAMBDA * 5;

     }

     rcc->buffer_index = s->avctx->rc_initial_buffer_occupancy;

     if (!rcc->buffer_index)
         rcc->buffer_index = s->avctx->rc_buffer_size * 3 / 4;

     if (s->flags & CODEC_FLAG_PASS2) {

         int i;

         char *p;

         /* find number of pics */

         p = s->avctx->stats_in;
         for (i = -1; p; i++)
             p = strchr(p + 1, ';');
         i += s->max_b_frames;
         if (i <= 0 || i >= INT_MAX / sizeof(RateControlEntry))

             return -1;

         rcc->entry       = av_mallocz(i * sizeof(RateControlEntry));
         rcc->num_entries = i;
 
         /* init all to skipped p frames
          * (with b frames we might have a not encoded frame at the end FIXME) */
         for (i = 0; i < rcc->num_entries; i++) {
             RateControlEntry *rce = &rcc->entry[i];
 
             rce->pict_type  = rce->new_pict_type = AV_PICTURE_TYPE_P;
             rce->qscale     = rce->new_qscale    = FF_QP2LAMBDA * 2;
             rce->misc_bits  = s->mb_num + 10;
             rce->mb_var_sum = s->mb_num * 100;

         }
 

         /* read stats */

         p = s->avctx->stats_in;
         for (i = 0; i < rcc->num_entries - s->max_b_frames; i++) {

             RateControlEntry *rce;
             int picture_number;
             int e;

             char *next;
 

             next = strchr(p, ';');
             if (next) {
                 (*next) = 0; // sscanf in unbelievably slow on looong strings // FIXME copy / do not write

                 next++;
             }

             e = sscanf(p, " in:%d ", &picture_number);

 
             assert(picture_number >= 0);
             assert(picture_number < rcc->num_entries);

             rce = &rcc->entry[picture_number];
 
             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",
                         &rce->pict_type, &rce->qscale, &rce->i_tex_bits, &rce->p_tex_bits,
                         &rce->mv_bits, &rce->misc_bits,
                         &rce->f_code, &rce->b_code,
                         &rce->mc_mb_var_sum, &rce->mb_var_sum,
                         &rce->i_count, &rce->skip_count, &rce->header_bits);
             if (e != 14) {
                 av_log(s->avctx, AV_LOG_ERROR,
                        "statistics are damaged at line %d, parser out=%d\n",
                        i, e);

                 return -1;
             }

             p = next;

         }

         if (init_pass2(s) < 0)
             return -1;

         // FIXME maybe move to end
         if ((s->flags & CODEC_FLAG_PASS2) && s->avctx->rc_strategy == FF_RC_STRATEGY_XVID) {

 #if CONFIG_LIBXVID

             return ff_xvid_rate_control_init(s);

 #else

             av_log(s->avctx, AV_LOG_ERROR,
                    "Xvid ratecontrol requires libavcodec compiled with Xvid support.\n");

             return -1;

 #endif

         }

     }

     if (!(s->flags & CODEC_FLAG_PASS2)) {
         rcc->short_term_qsum   = 0.001;
         rcc->short_term_qcount = 0.001;

         rcc->pass1_rc_eq_output_sum = 0.001;
         rcc->pass1_wanted_bits      = 0.001;

         if (s->avctx->qblur > 1.0) {

             av_log(s->avctx, AV_LOG_ERROR, "qblur too large\n");
             return -1;
         }

         /* init stuff with the user specified complexity */

         if (s->avctx->rc_initial_cplx) {
             for (i = 0; i < 60 * 30; i++) {
                 double bits = s->avctx->rc_initial_cplx * (i / 10000.0 + 1.0) * s->mb_num;

                 RateControlEntry rce;

                 if (i % ((s->gop_size + 3) / 4) == 0)
                     rce.pict_type = AV_PICTURE_TYPE_I;
                 else if (i % (s->max_b_frames + 1))
                     rce.pict_type = AV_PICTURE_TYPE_B;
                 else
                     rce.pict_type = AV_PICTURE_TYPE_P;
 
                 rce.new_pict_type = rce.pict_type;
                 rce.mc_mb_var_sum = bits * s->mb_num / 100000;
                 rce.mb_var_sum    = s->mb_num;
 
                 rce.qscale    = FF_QP2LAMBDA * 2;
                 rce.f_code    = 2;
                 rce.b_code    = 1;
                 rce.misc_bits = 1;
 
                 if (s->pict_type == AV_PICTURE_TYPE_I) {
                     rce.i_count    = s->mb_num;
                     rce.i_tex_bits = bits;
                     rce.p_tex_bits = 0;
                     rce.mv_bits    = 0;
                 } else {
                     rce.i_count    = 0; // FIXME we do know this approx
                     rce.i_tex_bits = 0;
                     rce.p_tex_bits = bits * 0.9;
                     rce.mv_bits    = bits * 0.1;

                 }

                 rcc->i_cplx_sum[rce.pict_type]  += rce.i_tex_bits * rce.qscale;
                 rcc->p_cplx_sum[rce.pict_type]  += rce.p_tex_bits * rce.qscale;

                 rcc->mv_bits_sum[rce.pict_type] += rce.mv_bits;

                 rcc->frame_count[rce.pict_type]++;
 
                 get_qscale(s, &rce, rcc->pass1_wanted_bits / rcc->pass1_rc_eq_output_sum, i);

                 // FIXME misbehaves a little for variable fps

                 rcc->pass1_wanted_bits += s->bit_rate / get_fps(s->avctx);

             }
         }
     }

     return 0;
 }
 
 void ff_rate_control_uninit(MpegEncContext *s)
 {

     RateControlContext *rcc = &s->rc_context;

     emms_c();
 

     av_expr_free(rcc->rc_eq_eval);

     av_freep(&rcc->entry);

 #if CONFIG_LIBXVID

     if ((s->flags & CODEC_FLAG_PASS2) && s->avctx->rc_strategy == FF_RC_STRATEGY_XVID)

         ff_xvid_rate_control_uninit(s);

 #endif

 }
 

 int ff_vbv_update(MpegEncContext *s, int frame_size)
 {
     RateControlContext *rcc = &s->rc_context;

     const double fps        = get_fps(s->avctx);

     const int buffer_size   = s->avctx->rc_buffer_size;
     const double min_rate   = s->avctx->rc_min_rate / fps;
     const double max_rate   = s->avctx->rc_max_rate / fps;

     av_dlog(s, "%d %f %d %f %f\n",
             buffer_size, rcc->buffer_index, frame_size, min_rate, max_rate);

 
     if (buffer_size) {

         int left;
 

         rcc->buffer_index -= frame_size;
         if (rcc->buffer_index < 0) {

             av_log(s->avctx, AV_LOG_ERROR, "rc buffer underflow\n");

             rcc->buffer_index = 0;

         }
 

         left = buffer_size - rcc->buffer_index - 1;

         rcc->buffer_index += av_clip(left, min_rate, max_rate);

         if (rcc->buffer_index > buffer_size) {
             int stuffing = ceil((rcc->buffer_index - buffer_size) / 8);

             if (stuffing < 4 && s->codec_id == AV_CODEC_ID_MPEG4)
                 stuffing = 4;
             rcc->buffer_index -= 8 * stuffing;

             if (s->avctx->debug & FF_DEBUG_RC)

                 av_log(s->avctx, AV_LOG_DEBUG, "stuffing %d bytes\n", stuffing);
 
             return stuffing;

         }

     }

     return 0;

 }
 
 /**

  * Modify the bitrate curve from pass1 for one frame.

  */

 static double get_qscale(MpegEncContext *s, RateControlEntry *rce,
                          double rate_factor, int frame_num)
 {
     RateControlContext *rcc = &s->rc_context;
     AVCodecContext *a       = s->avctx;
     const int pict_type     = rce->new_pict_type;
     const double mb_num     = s->mb_num;

     double q, bits;
     int i;
 

     double const_values[] = {

         M_PI,
         M_E,

         rce->i_tex_bits * rce->qscale,
         rce->p_tex_bits * rce->qscale,
         (rce->i_tex_bits + rce->p_tex_bits) * (double)rce->qscale,
         rce->mv_bits / mb_num,
         rce->pict_type == AV_PICTURE_TYPE_B ? (rce->f_code + rce->b_code) * 0.5 : rce->f_code,
         rce->i_count / mb_num,
         rce->mc_mb_var_sum / mb_num,
         rce->mb_var_sum / mb_num,

         rce->pict_type == AV_PICTURE_TYPE_I,
         rce->pict_type == AV_PICTURE_TYPE_P,
         rce->pict_type == AV_PICTURE_TYPE_B,

         rcc->qscale_sum[pict_type] / (double)rcc->frame_count[pict_type],

         a->qcompress,

 #if 0
         rcc->last_qscale_for[AV_PICTURE_TYPE_I],

         rcc->last_qscale_for[AV_PICTURE_TYPE_P],
         rcc->last_qscale_for[AV_PICTURE_TYPE_B],

         rcc->next_non_b_qscale,
 #endif

         rcc->i_cplx_sum[AV_PICTURE_TYPE_I] / (double)rcc->frame_count[AV_PICTURE_TYPE_I],
         rcc->i_cplx_sum[AV_PICTURE_TYPE_P] / (double)rcc->frame_count[AV_PICTURE_TYPE_P],
         rcc->p_cplx_sum[AV_PICTURE_TYPE_P] / (double)rcc->frame_count[AV_PICTURE_TYPE_P],
         rcc->p_cplx_sum[AV_PICTURE_TYPE_B] / (double)rcc->frame_count[AV_PICTURE_TYPE_B],

         (rcc->i_cplx_sum[pict_type] + rcc->p_cplx_sum[pict_type]) / (double)rcc->frame_count[pict_type],
         0
     };
 

     bits = av_expr_eval(rcc->rc_eq_eval, const_values, rce);

     if (isnan(bits)) {

         av_log(s->avctx, AV_LOG_ERROR, "Error evaluating rc_eq \"%s\"\n", s->avctx->rc_eq);

         return -1;
     }

     rcc->pass1_rc_eq_output_sum += bits;
     bits *= rate_factor;
     if (bits < 0.0)
         bits = 0.0;
     bits += 1.0; // avoid 1/0 issues

     /* user override */

     for (i = 0; i < s->avctx->rc_override_count; i++) {
         RcOverride *rco = s->avctx->rc_override;
         if (rco[i].start_frame > frame_num)
             continue;
         if (rco[i].end_frame < frame_num)
             continue;
 
         if (rco[i].qscale)
             bits = qp2bits(rce, rco[i].qscale);  // FIXME move at end to really force it?

         else

             bits *= rco[i].quality_factor;

     }
 

     q = bits2qp(rce, bits);

     /* I/B difference */

     if (pict_type == AV_PICTURE_TYPE_I && s->avctx->i_quant_factor < 0.0)
         q = -q * s->avctx->i_quant_factor + s->avctx->i_quant_offset;
     else if (pict_type == AV_PICTURE_TYPE_B && s->avctx->b_quant_factor < 0.0)
         q = -q * s->avctx->b_quant_factor + s->avctx->b_quant_offset;
     if (q < 1)
         q = 1;

     return q;
 }
 

 static double get_diff_limited_q(MpegEncContext *s, RateControlEntry *rce, double q)
 {
     RateControlContext *rcc   = &s->rc_context;
     AVCodecContext *a         = s->avctx;
     const int pict_type       = rce->new_pict_type;
     const double last_p_q     = rcc->last_qscale_for[AV_PICTURE_TYPE_P];
     const double last_non_b_q = rcc->last_qscale_for[rcc->last_non_b_pict_type];
 
     if (pict_type == AV_PICTURE_TYPE_I &&
         (a->i_quant_factor > 0.0 || rcc->last_non_b_pict_type == AV_PICTURE_TYPE_P))
         q = last_p_q * FFABS(a->i_quant_factor) + a->i_quant_offset;
     else if (pict_type == AV_PICTURE_TYPE_B &&
              a->b_quant_factor > 0.0)
         q = last_non_b_q * a->b_quant_factor + a->b_quant_offset;
     if (q < 1)
         q = 1;

     /* last qscale / qdiff stuff */

     if (rcc->last_non_b_pict_type == pict_type || pict_type != AV_PICTURE_TYPE_I) {
         double last_q     = rcc->last_qscale_for[pict_type];
         const int maxdiff = FF_QP2LAMBDA * a->max_qdiff;
 
         if (q > last_q + maxdiff)
             q = last_q + maxdiff;
         else if (q < last_q - maxdiff)
             q = last_q - maxdiff;

     }

     rcc->last_qscale_for[pict_type] = q; // Note we cannot do that after blurring

     if (pict_type != AV_PICTURE_TYPE_B)
         rcc->last_non_b_pict_type = pict_type;

     return q;
 }
 
 /**

  * Get the qmin & qmax for pict_type.

  */

 static void get_qminmax(int *qmin_ret, int *qmax_ret, MpegEncContext *s, int pict_type)
 {
     int qmin = s->avctx->lmin;
     int qmax = s->avctx->lmax;

     assert(qmin <= qmax);

     switch (pict_type) {
     case AV_PICTURE_TYPE_B:
         qmin = (int)(qmin * FFABS(s->avctx->b_quant_factor) + s->avctx->b_quant_offset + 0.5);
         qmax = (int)(qmax * FFABS(s->avctx->b_quant_factor) + s->avctx->b_quant_offset + 0.5);
         break;
     case AV_PICTURE_TYPE_I:
         qmin = (int)(qmin * FFABS(s->avctx->i_quant_factor) + s->avctx->i_quant_offset + 0.5);
         qmax = (int)(qmax * FFABS(s->avctx->i_quant_factor) + s->avctx->i_quant_offset + 0.5);
         break;

     }
 

     qmin = av_clip(qmin, 1, FF_LAMBDA_MAX);
     qmax = av_clip(qmax, 1, FF_LAMBDA_MAX);

     if (qmax < qmin)
         qmax = qmin;

     *qmin_ret = qmin;
     *qmax_ret = qmax;

 }
 

 static double modify_qscale(MpegEncContext *s, RateControlEntry *rce,
                             double q, int frame_num)
 {
     RateControlContext *rcc  = &s->rc_context;
     const double buffer_size = s->avctx->rc_buffer_size;

     const double fps         = get_fps(s->avctx);

     const double min_rate    = s->avctx->rc_min_rate / fps;
     const double max_rate    = s->avctx->rc_max_rate / fps;
     const int pict_type      = rce->new_pict_type;

     int qmin, qmax;

     get_qminmax(&qmin, &qmax, s, pict_type);
 
     /* modulation */

     if (s->avctx->rc_qmod_freq &&
         frame_num % s->avctx->rc_qmod_freq == 0 &&
         pict_type == AV_PICTURE_TYPE_P)
         q *= s->avctx->rc_qmod_amp;

 
     /* buffer overflow/underflow protection */

     if (buffer_size) {
         double expected_size = rcc->buffer_index;

         double q_limit;

         if (min_rate) {
             double d = 2 * (buffer_size - expected_size) / buffer_size;
             if (d > 1.0)
                 d = 1.0;
             else if (d < 0.0001)
                 d = 0.0001;
             q *= pow(d, 1.0 / s->avctx->rc_buffer_aggressivity);
 
             q_limit = bits2qp(rce,
                               FFMAX((min_rate - buffer_size + rcc->buffer_index) *
                                     s->avctx->rc_min_vbv_overflow_use, 1));
 
             if (q > q_limit) {
                 if (s->avctx->debug & FF_DEBUG_RC)
                     av_log(s->avctx, AV_LOG_DEBUG,
                            "limiting QP %f -> %f\n", q, q_limit);
                 q = q_limit;

             }

         }
 

         if (max_rate) {
             double d = 2 * expected_size / buffer_size;
             if (d > 1.0)
                 d = 1.0;
             else if (d < 0.0001)
                 d = 0.0001;
             q /= pow(d, 1.0 / s->avctx->rc_buffer_aggressivity);
 
             q_limit = bits2qp(rce,
                               FFMAX(rcc->buffer_index *
                                     s->avctx->rc_max_available_vbv_use,
                                     1));
             if (q < q_limit) {
                 if (s->avctx->debug & FF_DEBUG_RC)
                     av_log(s->avctx, AV_LOG_DEBUG,
                            "limiting QP %f -> %f\n", q, q_limit);
                 q = q_limit;

             }

         }
     }

     av_dlog(s, "q:%f max:%f min:%f size:%f index:%f agr:%f\n",
             q, max_rate, min_rate, buffer_size, rcc->buffer_index,
             s->avctx->rc_buffer_aggressivity);

     if (s->avctx->rc_qsquish == 0.0 || qmin == qmax) {
         if (q < qmin)
             q = qmin;
         else if (q > qmax)
             q = qmax;
     } else {
         double min2 = log(qmin);
         double max2 = log(qmax);
 
         q  = log(q);
         q  = (q - min2) / (max2 - min2) - 0.5;
         q *= -4.0;
         q  = 1.0 / (1.0 + exp(q));
         q  = q * (max2 - min2) + min2;
 
         q = exp(q);

     }

     return q;
 }
 

 // ----------------------------------

 // 1 Pass Code
 

 static double predict_size(Predictor *p, double q, double var)

 {

     return p->coeff * var / (q * p->count);

 }
 
 static void update_predictor(Predictor *p, double q, double var, double size)
 {

     double new_coeff = size * q / (var + 1);
     if (var < 10)
         return;

     p->count *= p->decay;
     p->coeff *= p->decay;

     p->count++;

     p->coeff += new_coeff;

 }
 

 static void adaptive_quantization(MpegEncContext *s, double q)
 {

     int i;

     const float lumi_masking         = s->avctx->lumi_masking / (128.0 * 128.0);
     const float dark_masking         = s->avctx->dark_masking / (128.0 * 128.0);
     const float temp_cplx_masking    = s->avctx->temporal_cplx_masking;

     const float spatial_cplx_masking = s->avctx->spatial_cplx_masking;

     const float p_masking            = s->avctx->p_masking;
     const float border_masking       = s->avctx->border_masking;
     float bits_sum                   = 0.0;
     float cplx_sum                   = 0.0;
     float *cplx_tab                  = s->cplx_tab;
     float *bits_tab                  = s->bits_tab;
     const int qmin                   = s->avctx->mb_lmin;
     const int qmax                   = s->avctx->mb_lmax;
     Picture *const pic               = &s->current_picture;
     const int mb_width               = s->mb_width;
     const int mb_height              = s->mb_height;
 
     for (i = 0; i < s->mb_num; i++) {
         const int mb_xy = s->mb_index2xy[i];
         float temp_cplx = sqrt(pic->mc_mb_var[mb_xy]); // FIXME merge in pow()
         float spat_cplx = sqrt(pic->mb_var[mb_xy]);
         const int lumi  = pic->mb_mean[mb_xy];

         float bits, cplx, factor;

         int mb_x = mb_xy % s->mb_stride;
         int mb_y = mb_xy / s->mb_stride;
         int mb_distance;
         float mb_factor = 0.0;

         if (spat_cplx < 4)
             spat_cplx = 4;              // FIXME finetune
         if (temp_cplx < 4)
             temp_cplx = 4;              // FIXME finetune
 
         if ((s->mb_type[mb_xy] & CANDIDATE_MB_TYPE_INTRA)) { // FIXME hq mode
             cplx   = spat_cplx;
             factor = 1.0 + p_masking;
         } else {
             cplx   = temp_cplx;
             factor = pow(temp_cplx, -temp_cplx_masking);

         }

         factor *= pow(spat_cplx, -spatial_cplx_masking);

         if (lumi > 127)
             factor *= (1.0 - (lumi - 128) * (lumi - 128) * lumi_masking);

         else

             factor *= (1.0 - (lumi - 128) * (lumi - 128) * dark_masking);
 
         if (mb_x < mb_width / 5) {
             mb_distance = mb_width / 5 - mb_x;
             mb_factor   = (float)mb_distance / (float)(mb_width / 5);
         } else if (mb_x > 4 * mb_width / 5) {
             mb_distance = mb_x - 4 * mb_width / 5;
             mb_factor   = (float)mb_distance / (float)(mb_width / 5);

         }

         if (mb_y < mb_height / 5) {
             mb_distance = mb_height / 5 - mb_y;
             mb_factor   = FFMAX(mb_factor,
                                 (float)mb_distance / (float)(mb_height / 5));
         } else if (mb_y > 4 * mb_height / 5) {
             mb_distance = mb_y - 4 * mb_height / 5;
             mb_factor   = FFMAX(mb_factor,
                                 (float)mb_distance / (float)(mb_height / 5));

         }
 

         factor *= 1.0 - border_masking * mb_factor;

         if (factor < 0.00001)
             factor = 0.00001;

         bits        = cplx * factor;
         cplx_sum   += cplx;
         bits_sum   += bits;
         cplx_tab[i] = cplx;
         bits_tab[i] = bits;

     }
 

     /* handle qmin/qmax clipping */

     if (s->flags & CODEC_FLAG_NORMALIZE_AQP) {
         float factor = bits_sum / cplx_sum;
         for (i = 0; i < s->mb_num; i++) {
             float newq = q * cplx_tab[i] / bits_tab[i];
             newq *= factor;

             if (newq > qmax) {

                 bits_sum -= bits_tab[i];

                 cplx_sum -= cplx_tab[i] * q / qmax;
             } else if (newq < qmin) {

                 bits_sum -= bits_tab[i];

                 cplx_sum -= cplx_tab[i] * q / qmin;

             }
         }

         if (bits_sum < 0.001)
             bits_sum = 0.001;
         if (cplx_sum < 0.001)
             cplx_sum = 0.001;

     }

     for (i = 0; i < s->mb_num; i++) {
         const int mb_xy = s->mb_index2xy[i];
         float newq      = q * cplx_tab[i] / bits_tab[i];

         int intq;
 

         if (s->flags & CODEC_FLAG_NORMALIZE_AQP) {
             newq *= bits_sum / cplx_sum;

         }
 

         intq = (int)(newq + 0.5);

         if (intq > qmax)
             intq = qmax;
         else if (intq < qmin)
             intq = qmin;
         s->lambda_table[mb_xy] = intq;

     }
 }

 void ff_get_2pass_fcode(MpegEncContext *s)
 {
     RateControlContext *rcc = &s->rc_context;
     RateControlEntry *rce   = &rcc->entry[s->picture_number];

     s->f_code = rce->f_code;
     s->b_code = rce->b_code;

 }
 

 // FIXME rd or at least approx for dquant

 float ff_rate_estimate_qscale(MpegEncContext *s, int dry_run)

 {
     float q;

     int qmin, qmax;

     float br_compensation;
     double diff;
     double short_term_q;
     double fps;

     int picture_number = s->picture_number;

     int64_t wanted_bits;

     RateControlContext *rcc = &s->rc_context;
     AVCodecContext *a       = s->avctx;

     RateControlEntry local_rce, *rce;
     double bits;
     double rate_factor;
     int var;

     const int pict_type = s->pict_type;
     Picture * const pic = &s->current_picture;

     emms_c();
 

 #if CONFIG_LIBXVID

     if ((s->flags & CODEC_FLAG_PASS2) &&
         s->avctx->rc_strategy == FF_RC_STRATEGY_XVID)

         return ff_xvid_rate_estimate_qscale(s, dry_run);

 #endif

     get_qminmax(&qmin, &qmax, s, pict_type);

     fps = get_fps(s->avctx);

     /* update predictors */
     if (picture_number > 2 && !dry_run) {
         const int last_var = s->last_pict_type == AV_PICTURE_TYPE_I ? rcc->last_mb_var_sum
                                                                     : rcc->last_mc_mb_var_sum;

         av_assert1(s->frame_bits >= s->stuffing_bits);

         update_predictor(&rcc->pred[s->last_pict_type],
                          rcc->last_qscale,

                          sqrt(last_var),
                          s->frame_bits - s->stuffing_bits);

     }
 

     if (s->flags & CODEC_FLAG_PASS2) {
         assert(picture_number >= 0);

         if (picture_number >= rcc->num_entries) {

             av_log(s, AV_LOG_ERROR, "Input is longer than 2-pass log file\n");
             return -1;
         }

         rce         = &rcc->entry[picture_number];
         wanted_bits = rce->expected_bits;
     } else {

         Picture *dts_pic;

         rce = &local_rce;

         /* FIXME add a dts field to AVFrame and ensure it is set and use it
          * here instead of reordering but the reordering is simpler for now
          * until H.264 B-pyramid must be handled. */
         if (s->pict_type == AV_PICTURE_TYPE_B || s->low_delay)
             dts_pic = s->current_picture_ptr;

         else

             dts_pic = s->last_picture_ptr;

         if (!dts_pic || dts_pic->f.pts == AV_NOPTS_VALUE)

             wanted_bits = (uint64_t)(s->bit_rate * (double)picture_number / fps);

         else

             wanted_bits = (uint64_t)(s->bit_rate * (double)dts_pic->f.pts / fps);

     }

     diff = s->total_bits - wanted_bits;
     br_compensation = (a->bit_rate_tolerance - diff) / a->bit_rate_tolerance;
     if (br_compensation <= 0.0)
         br_compensation = 0.001;

     var = pict_type == AV_PICTURE_TYPE_I ? pic->mb_var_sum : pic->mc_mb_var_sum;

     short_term_q = 0; /* avoid warning */

     if (s->flags & CODEC_FLAG_PASS2) {
         if (pict_type != AV_PICTURE_TYPE_I)

             assert(pict_type == rce->new_pict_type);
 

         q = rce->new_qscale / br_compensation;

         av_dlog(s, "%f %f %f last:%d var:%d type:%d//\n", q, rce->new_qscale,
                 br_compensation, s->frame_bits, var, pict_type);

     } else {
         rce->pict_type     =
         rce->new_pict_type = pict_type;
         rce->mc_mb_var_sum = pic->mc_mb_var_sum;
         rce->mb_var_sum    = pic->mb_var_sum;
         rce->qscale        = FF_QP2LAMBDA * 2;
         rce->f_code        = s->f_code;
         rce->b_code        = s->b_code;
         rce->misc_bits     = 1;
 
         bits = predict_size(&rcc->pred[pict_type], rce->qscale, sqrt(var));
         if (pict_type == AV_PICTURE_TYPE_I) {
             rce->i_count    = s->mb_num;
             rce->i_tex_bits = bits;
             rce->p_tex_bits = 0;
             rce->mv_bits    = 0;
         } else {
             rce->i_count    = 0;    // FIXME we do know this approx
             rce->i_tex_bits = 0;
             rce->p_tex_bits = bits * 0.9;
             rce->mv_bits    = bits * 0.1;

         }

         rcc->i_cplx_sum[pict_type]  += rce->i_tex_bits * rce->qscale;
         rcc->p_cplx_sum[pict_type]  += rce->p_tex_bits * rce->qscale;

         rcc->mv_bits_sum[pict_type] += rce->mv_bits;

         rcc->frame_count[pict_type]++;

         bits        = rce->i_tex_bits + rce->p_tex_bits;
         rate_factor = rcc->pass1_wanted_bits /
                       rcc->pass1_rc_eq_output_sum * br_compensation;

         q = get_qscale(s, rce, rate_factor, picture_number);

         if (q < 0)
             return -1;

         assert(q > 0.0);
         q = get_diff_limited_q(s, rce, q);
         assert(q > 0.0);

         // FIXME type dependent blur like in 2-pass
         if (pict_type == AV_PICTURE_TYPE_P || s->intra_only) {
             rcc->short_term_qsum   *= a->qblur;
             rcc->short_term_qcount *= a->qblur;

             rcc->short_term_qsum += q;

             rcc->short_term_qcount++;

             q = short_term_q = rcc->short_term_qsum / rcc->short_term_qcount;

         }

         assert(q > 0.0);

         q = modify_qscale(s, rce, q, picture_number);

         rcc->pass1_wanted_bits += s->bit_rate / fps;

         assert(q > 0.0);

     }

     if (s->avctx->debug & FF_DEBUG_RC) {
         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",
                av_get_picture_type_char(pict_type),
                qmin, q, qmax, picture_number,
                (int)wanted_bits / 1000, (int)s->total_bits / 1000,
                br_compensation, short_term_q, s->frame_bits,
                pic->mb_var_sum, pic->mc_mb_var_sum,
                s->bit_rate / 1000, (int)fps);

     }

     if (q < qmin)
         q = qmin;
     else if (q > qmax)
         q = qmax;

     if (s->adaptive_quant)

         adaptive_quantization(s, q);
     else

         q = (int)(q + 0.5);

     if (!dry_run) {
         rcc->last_qscale        = q;
         rcc->last_mc_mb_var_sum = pic->mc_mb_var_sum;
         rcc->last_mb_var_sum    = pic->mb_var_sum;

     }

     return q;

 }
 

 // ----------------------------------------------

 // 2-Pass code
 
 static int init_pass2(MpegEncContext *s)
 {

     RateControlContext *rcc = &s->rc_context;
     AVCodecContext *a       = s->avctx;

     int i, toobig;

     double fps             = get_fps(s->avctx);

     double complexity[5]   = { 0 }; // approximate bits at quant=1
     uint64_t const_bits[5] = { 0 }; // quantizer independent bits

     uint64_t all_const_bits;

     uint64_t all_available_bits = (uint64_t)(s->bit_rate *
                                              (double)rcc->num_entries / fps);
     double rate_factor          = 0;

     double step;

     const int filter_size = (int)(a->qblur * 4) | 1;

     double expected_bits;

     double *qscale, *blurred_qscale, qscale_sum;

 
     /* find complexity & const_bits & decide the pict_types */

     for (i = 0; i < rcc->num_entries; i++) {
         RateControlEntry *rce = &rcc->entry[i];

         rce->new_pict_type                = rce->pict_type;
         rcc->i_cplx_sum[rce->pict_type]  += rce->i_tex_bits * rce->qscale;
         rcc->p_cplx_sum[rce->pict_type]  += rce->p_tex_bits * rce->qscale;

         rcc->mv_bits_sum[rce->pict_type] += rce->mv_bits;

         rcc->frame_count[rce->pict_type]++;

         complexity[rce->new_pict_type] += (rce->i_tex_bits + rce->p_tex_bits) *
                                           (double)rce->qscale;
         const_bits[rce->new_pict_type] += rce->mv_bits + rce->misc_bits;

     }

     all_const_bits = const_bits[AV_PICTURE_TYPE_I] +
                      const_bits[AV_PICTURE_TYPE_P] +
                      const_bits[AV_PICTURE_TYPE_B];
 
     if (all_available_bits < all_const_bits) {

         av_log(s->avctx, AV_LOG_ERROR, "requested bitrate is too low\n");

         return -1;
     }

     qscale         = av_malloc(sizeof(double) * rcc->num_entries);
     blurred_qscale = av_malloc(sizeof(double) * rcc->num_entries);

     toobig = 0;

     for (step = 256 * 256; step > 0.0000001; step *= 0.5) {
         expected_bits = 0;
         rate_factor  += step;

         rcc->buffer_index = s->avctx->rc_buffer_size / 2;

         /* find qscale */

         for (i = 0; i < rcc->num_entries; i++) {
             RateControlEntry *rce = &rcc->entry[i];
 
             qscale[i] = get_qscale(s, &rcc->entry[i], rate_factor, i);

             rcc->last_qscale_for[rce->pict_type] = qscale[i];

         }

         assert(filter_size % 2 == 1);

 
         /* fixed I/B QP relative to P mode */

         for (i = FFMAX(0, rcc->num_entries - 300); i < rcc->num_entries; i++) {
             RateControlEntry *rce = &rcc->entry[i];

             qscale[i] = get_diff_limited_q(s, rce, qscale[i]);

         }
 

         for (i = rcc->num_entries - 1; i >= 0; i--) {
             RateControlEntry *rce = &rcc->entry[i];

             qscale[i] = get_diff_limited_q(s, rce, qscale[i]);

         }

         /* smooth curve */

         for (i = 0; i < rcc->num_entries; i++) {
             RateControlEntry *rce = &rcc->entry[i];
             const int pict_type   = rce->new_pict_type;

             int j;

             double q = 0.0, sum = 0.0;
 
             for (j = 0; j < filter_size; j++) {
                 int index    = i + j - filter_size / 2;
                 double d     = index - i;
                 double coeff = a->qblur == 0 ? 1.0 : exp(-d * d / (a->qblur * a->qblur));
 
                 if (index < 0 || index >= rcc->num_entries)
                     continue;
                 if (pict_type != rcc->entry[index].new_pict_type)
                     continue;
                 q   += qscale[index] * coeff;
                 sum += coeff;

             }

             blurred_qscale[i] = q / sum;

         }

         /* find expected bits */

         for (i = 0; i < rcc->num_entries; i++) {
             RateControlEntry *rce = &rcc->entry[i];

             double bits;
 

             rce->new_qscale = modify_qscale(s, rce, blurred_qscale[i], i);
 
             bits  = qp2bits(rce, rce->new_qscale) + rce->mv_bits + rce->misc_bits;
             bits += 8 * ff_vbv_update(s, bits);
 
             rce->expected_bits = expected_bits;
             expected_bits     += bits;

         }
 

         av_dlog(s->avctx,
                 "expected_bits: %f all_available_bits: %d rate_factor: %f\n",
                 expected_bits, (int)all_available_bits, rate_factor);

         if (expected_bits > all_available_bits) {
             rate_factor -= step;

             ++toobig;
         }

     }

     av_free(qscale);

     av_free(blurred_qscale);

     /* check bitrate calculations and print info */
     qscale_sum = 0.0;

     for (i = 0; i < rcc->num_entries; i++) {

         av_dlog(s, "[lavc rc] entry[%d].new_qscale = %.3f  qp = %.3f\n",
                 i,
                 rcc->entry[i].new_qscale,
                 rcc->entry[i].new_qscale / FF_QP2LAMBDA);

         qscale_sum += av_clip(rcc->entry[i].new_qscale / FF_QP2LAMBDA,
                               s->avctx->qmin, s->avctx->qmax);

     }
     assert(toobig <= 40);
     av_log(s->avctx, AV_LOG_DEBUG,

            "[lavc rc] requested bitrate: %d bps  expected bitrate: %d bps\n",
            s->bit_rate,
            (int)(expected_bits / ((double)all_available_bits / s->bit_rate)));

     av_log(s->avctx, AV_LOG_DEBUG,

            "[lavc rc] estimated target average qp: %.3f\n",
            (float)qscale_sum / rcc->num_entries);

     if (toobig == 0) {
         av_log(s->avctx, AV_LOG_INFO,

                "[lavc rc] Using all of requested bitrate is not "
                "necessary for this video with these parameters.\n");

     } else if (toobig == 40) {
         av_log(s->avctx, AV_LOG_ERROR,

                "[lavc rc] Error: bitrate too low for this video "
                "with these parameters.\n");

         return -1;

     } else if (fabs(expected_bits / all_available_bits - 1.0) > 0.01) {

         av_log(s->avctx, AV_LOG_ERROR,

                "[lavc rc] Error: 2pass curve failed to converge\n");

         return -1;

     }
 

     return 0;

 }