libvpx: Pull from upstream

source/libvpx/vp9/encoder/vp9_firstpass.c

 /*
  *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 20 matching lines @@
 #include "vp9/encoder/vp9_extend.h"
 #include "vp9/encoder/vp9_firstpass.h"
 #include "vp9/encoder/vp9_mcomp.h"
 #include "vp9/encoder/vp9_quantize.h"
 #include "vp9/encoder/vp9_rd.h"
 #include "vp9/encoder/vp9_variance.h"
 
 #define OUTPUT_FPF          0
 #define ARF_STATS_OUTPUT    0
 
+#define BOOST_BREAKOUT      12.5
 #define BOOST_FACTOR        12.5
-#define ERR_DIVISOR         100.0
-#define FACTOR_PT_LOW       0.5
-#define FACTOR_PT_HIGH      0.9
+#define ERR_DIVISOR         128.0
+#define FACTOR_PT_LOW       0.70
+#define FACTOR_PT_HIGH      0.90
 #define FIRST_PASS_Q        10.0
 #define GF_MAX_BOOST        96.0
 #define INTRA_MODE_PENALTY  1024
 #define KF_MAX_BOOST        128.0
+#define MIN_ARF_GF_BOOST    240
 #define MIN_DECAY_FACTOR    0.01
 #define MIN_GF_INTERVAL     4
 #define MIN_KF_BOOST        300
 #define NEW_MV_MODE_PENALTY 32
 #define SVC_FACTOR_PT_LOW   0.45
 
 #define DOUBLE_DIVIDE_CHECK(x) ((x) < 0 ? (x) - 0.000001 : (x) + 0.000001)
 
 #if ARF_STATS_OUTPUT
 unsigned int arf_count = 0;
 #endif
 
 static void swap_yv12(YV12_BUFFER_CONFIG *a, YV12_BUFFER_CONFIG *b) {
   YV12_BUFFER_CONFIG temp = *a;
   *a = *b;
   *b = temp;
 }
 
-static int gfboost_qadjust(int qindex, vpx_bit_depth_t bit_depth) {
-  const double q = vp9_convert_qindex_to_q(qindex, bit_depth);
-  return (int)((0.00000828 * q * q * q) +
-               (-0.0055 * q * q) +
-               (1.32 * q) + 79.3);
-}
-
 // Resets the first pass file to the given position using a relative seek from
 // the current position.
 static void reset_fpf_position(TWO_PASS *p,
                                const FIRSTPASS_STATS *position) {
   p->stats_in = position;
 }
 
 // Read frame stats at an offset from the current position.
 static const FIRSTPASS_STATS *read_frame_stats(const TWO_PASS *p, int offset) {
   if ((offset >= 0 && p->stats_in + offset >= p->stats_in_end) ||
@@ skipping 190 matching lines @@
 
 static unsigned int get_prediction_error(BLOCK_SIZE bsize,
                                          const struct buf_2d *src,
                                          const struct buf_2d *ref) {
   unsigned int sse;
   const vp9_variance_fn_t fn = get_block_variance_fn(bsize);
   fn(src->buf, src->stride, ref->buf, ref->stride, &sse);
   return sse;
 }
 
+#if CONFIG_VP9_HIGHBITDEPTH
+static vp9_variance_fn_t highbd_get_block_variance_fn(BLOCK_SIZE bsize,
+                                                      int bd) {
+  switch (bd) {
+    default:
+      switch (bsize) {
+        case BLOCK_8X8:
+          return vp9_highbd_mse8x8;
+        case BLOCK_16X8:
+          return vp9_highbd_mse16x8;
+        case BLOCK_8X16:
+          return vp9_highbd_mse8x16;
+        default:
+          return vp9_highbd_mse16x16;
+      }
+      break;
+    case 10:
+      switch (bsize) {
+        case BLOCK_8X8:
+          return vp9_highbd_10_mse8x8;
+        case BLOCK_16X8:
+          return vp9_highbd_10_mse16x8;
+        case BLOCK_8X16:
+          return vp9_highbd_10_mse8x16;
+        default:
+          return vp9_highbd_10_mse16x16;
+      }
+      break;
+    case 12:
+      switch (bsize) {
+        case BLOCK_8X8:
+          return vp9_highbd_12_mse8x8;
+        case BLOCK_16X8:
+          return vp9_highbd_12_mse16x8;
+        case BLOCK_8X16:
+          return vp9_highbd_12_mse8x16;
+        default:
+          return vp9_highbd_12_mse16x16;
+      }
+      break;
+  }
+}
+
+static unsigned int highbd_get_prediction_error(BLOCK_SIZE bsize,
+                                                const struct buf_2d *src,
+                                                const struct buf_2d *ref,
+                                                int bd) {
+  unsigned int sse;
+  const vp9_variance_fn_t fn = highbd_get_block_variance_fn(bsize, bd);
+  fn(src->buf, src->stride, ref->buf, ref->stride, &sse);
+  return sse;
+}
+#endif  // CONFIG_VP9_HIGHBITDEPTH
+
 // Refine the motion search range according to the frame dimension
 // for first pass test.
 static int get_search_range(const VP9_COMMON *cm) {
   int sr = 0;
   const int dim = MIN(cm->width, cm->height);
 
   while ((dim << sr) < MAX_FULL_PEL_VAL)
     ++sr;
   return sr;
 }
@@ skipping 10 matching lines @@
   const int new_mv_mode_penalty = NEW_MV_MODE_PENALTY;
 
   int step_param = 3;
   int further_steps = (MAX_MVSEARCH_STEPS - 1) - step_param;
   const int sr = get_search_range(&cpi->common);
   step_param += sr;
   further_steps -= sr;
 
   // Override the default variance function to use MSE.
   v_fn_ptr.vf = get_block_variance_fn(bsize);
+#if CONFIG_VP9_HIGHBITDEPTH
+  if (xd->cur_buf->flags & YV12_FLAG_HIGHBITDEPTH) {
+    v_fn_ptr.vf = highbd_get_block_variance_fn(bsize, xd->bd);
+  }
+#endif  // CONFIG_VP9_HIGHBITDEPTH
 
   // Center the initial step/diamond search on best mv.
   tmp_err = cpi->diamond_search_sad(x, &cpi->ss_cfg, &ref_mv_full, &tmp_mv,
                                     step_param,
                                     x->sadperbit16, &num00, &v_fn_ptr, ref_mv);
   if (tmp_err < INT_MAX)
     tmp_err = vp9_get_mvpred_var(x, &tmp_mv, ref_mv, &v_fn_ptr, 1);
   if (tmp_err < INT_MAX - new_mv_mode_penalty)
     tmp_err += new_mv_mode_penalty;
 
@@ skipping 231 matching lines @@
         error_weight = vp9_vaq_inv_q_ratio(energy);
       }
 
       // Do intra 16x16 prediction.
       x->skip_encode = 0;
       xd->mi[0].src_mi->mbmi.mode = DC_PRED;
       xd->mi[0].src_mi->mbmi.tx_size = use_dc_pred ?
          (bsize >= BLOCK_16X16 ? TX_16X16 : TX_8X8) : TX_4X4;
       vp9_encode_intra_block_plane(x, bsize, 0);
       this_error = vp9_get_mb_ss(x->plane[0].src_diff);
+#if CONFIG_VP9_HIGHBITDEPTH
+      if (cm->use_highbitdepth) {
+        switch (cm->bit_depth) {
+          case VPX_BITS_8:
+            break;
+          case VPX_BITS_10:
+            this_error >>= 4;
+            break;
+          case VPX_BITS_12:
+            this_error >>= 8;
+            break;
+          default:
+            assert(0 && "cm->bit_depth should be VPX_BITS_8, "
+                        "VPX_BITS_10 or VPX_BITS_12");
+            return;
+        }
+      }
+#endif  // CONFIG_VP9_HIGHBITDEPTH
 
       if (cpi->oxcf.aq_mode == VARIANCE_AQ) {
         vp9_clear_system_state();
         this_error = (int)(this_error * error_weight);
       }
 
       // Intrapenalty below deals with situations where the intra and inter
       // error scores are very low (e.g. a plain black frame).
       // We do not have special cases in first pass for 0,0 and nearest etc so
       // all inter modes carry an overhead cost estimate for the mv.
@@ skipping 19 matching lines @@
 
       // Other than for the first frame do a motion search.
       if ((lc == NULL && cm->current_video_frame > 0) ||
           (lc != NULL && lc->current_video_frame_in_layer > 0)) {
         int tmp_err, motion_error, raw_motion_error;
         // Assume 0,0 motion with no mv overhead.
         MV mv = {0, 0} , tmp_mv = {0, 0};
         struct buf_2d unscaled_last_source_buf_2d;
 
         xd->plane[0].pre[0].buf = first_ref_buf->y_buffer + recon_yoffset;
-        motion_error = get_prediction_error(bsize, &x->plane[0].src,
-                                            &xd->plane[0].pre[0]);
+#if CONFIG_VP9_HIGHBITDEPTH
+        if (xd->cur_buf->flags & YV12_FLAG_HIGHBITDEPTH) {
+          motion_error = highbd_get_prediction_error(
+              bsize, &x->plane[0].src, &xd->plane[0].pre[0], xd->bd);
+        } else {
+          motion_error = get_prediction_error(
+              bsize, &x->plane[0].src, &xd->plane[0].pre[0]);
+        }
+#else
+        motion_error = get_prediction_error(
+            bsize, &x->plane[0].src, &xd->plane[0].pre[0]);
+#endif  // CONFIG_VP9_HIGHBITDEPTH
 
         // Compute the motion error of the 0,0 motion using the last source
         // frame as the reference. Skip the further motion search on
         // reconstructed frame if this error is small.
         unscaled_last_source_buf_2d.buf =
             cpi->unscaled_last_source->y_buffer + recon_yoffset;
         unscaled_last_source_buf_2d.stride =
             cpi->unscaled_last_source->y_stride;
-        raw_motion_error = get_prediction_error(bsize, &x->plane[0].src,
-                                                &unscaled_last_source_buf_2d);
+#if CONFIG_VP9_HIGHBITDEPTH
+        if (xd->cur_buf->flags & YV12_FLAG_HIGHBITDEPTH) {
+          raw_motion_error = highbd_get_prediction_error(
+              bsize, &x->plane[0].src, &unscaled_last_source_buf_2d, xd->bd);
+        } else {
+          raw_motion_error = get_prediction_error(
+              bsize, &x->plane[0].src, &unscaled_last_source_buf_2d);
+        }
+#else
+        raw_motion_error = get_prediction_error(
+            bsize, &x->plane[0].src, &unscaled_last_source_buf_2d);
+#endif  // CONFIG_VP9_HIGHBITDEPTH
 
         // TODO(pengchong): Replace the hard-coded threshold
         if (raw_motion_error > 25 || lc != NULL) {
           // Test last reference frame using the previous best mv as the
           // starting point (best reference) for the search.
           first_pass_motion_search(cpi, x, &best_ref_mv, &mv, &motion_error);
           if (cpi->oxcf.aq_mode == VARIANCE_AQ) {
             vp9_clear_system_state();
             motion_error = (int)(motion_error * error_weight);
           }
@@ skipping 15 matching lines @@
           }
 
           // Search in an older reference frame.
           if (((lc == NULL && cm->current_video_frame > 1) ||
                (lc != NULL && lc->current_video_frame_in_layer > 1))
               && gld_yv12 != NULL) {
             // Assume 0,0 motion with no mv overhead.
             int gf_motion_error;
 
             xd->plane[0].pre[0].buf = gld_yv12->y_buffer + recon_yoffset;
-            gf_motion_error = get_prediction_error(bsize, &x->plane[0].src,
-                                                   &xd->plane[0].pre[0]);
+#if CONFIG_VP9_HIGHBITDEPTH
+            if (xd->cur_buf->flags & YV12_FLAG_HIGHBITDEPTH) {
+              gf_motion_error = highbd_get_prediction_error(
+                  bsize, &x->plane[0].src, &xd->plane[0].pre[0], xd->bd);
+            } else {
+              gf_motion_error = get_prediction_error(
+                  bsize, &x->plane[0].src, &xd->plane[0].pre[0]);
+            }
+#else
+            gf_motion_error = get_prediction_error(
+                bsize, &x->plane[0].src, &xd->plane[0].pre[0]);
+#endif  // CONFIG_VP9_HIGHBITDEPTH
 
             first_pass_motion_search(cpi, x, &zero_mv, &tmp_mv,
                                      &gf_motion_error);
             if (cpi->oxcf.aq_mode == VARIANCE_AQ) {
               vp9_clear_system_state();
               gf_motion_error = (int)(gf_motion_error * error_weight);
             }
 
             if (gf_motion_error < motion_error && gf_motion_error < this_error)
               ++second_ref_count;
@@ skipping 279 matching lines @@
 static double calc_correction_factor(double err_per_mb,
                                      double err_divisor,
                                      double pt_low,
                                      double pt_high,
                                      int q,
                                      vpx_bit_depth_t bit_depth) {
   const double error_term = err_per_mb / err_divisor;
 
   // Adjustment based on actual quantizer to power term.
   const double power_term =
-      MIN(vp9_convert_qindex_to_q(q, bit_depth) * 0.0125 + pt_low, pt_high);
+      MIN(vp9_convert_qindex_to_q(q, bit_depth) * 0.01 + pt_low, pt_high);
 
   // Calculate correction factor.
   if (power_term < 1.0)
     assert(error_term >= 0.0);
 
   return fclamp(pow(error_term, power_term), 0.05, 5.0);
 }
 
+// Larger image formats are expected to be a little harder to code relatively
+// given the same prediction error score. This in part at least relates to the
+// increased size and hence coding cost of motion vectors.
+#define EDIV_SIZE_FACTOR 800
+
 static int get_twopass_worst_quality(const VP9_COMP *cpi,
                                      const FIRSTPASS_STATS *stats,
                                      int section_target_bandwidth) {
   const RATE_CONTROL *const rc = &cpi->rc;
   const VP9EncoderConfig *const oxcf = &cpi->oxcf;
 
   if (section_target_bandwidth <= 0) {
     return rc->worst_quality;  // Highest value allowed
   } else {
     const int num_mbs = cpi->common.MBs;
     const double section_err = stats->coded_error / stats->count;
     const double err_per_mb = section_err / num_mbs;
     const double speed_term = 1.0 + 0.04 * oxcf->speed;
+    const double ediv_size_correction = num_mbs / EDIV_SIZE_FACTOR;
     const int target_norm_bits_per_mb = ((uint64_t)section_target_bandwidth <<
                                          BPER_MB_NORMBITS) / num_mbs;
+
     int q;
     int is_svc_upper_layer = 0;
     if (is_two_pass_svc(cpi) && cpi->svc.spatial_layer_id > 0)
       is_svc_upper_layer = 1;
 
     // Try and pick a max Q that will be high enough to encode the
     // content at the given rate.
     for (q = rc->best_quality; q < rc->worst_quality; ++q) {
       const double factor =
-          calc_correction_factor(err_per_mb, ERR_DIVISOR,
+          calc_correction_factor(err_per_mb, ERR_DIVISOR - ediv_size_correction,
                                  is_svc_upper_layer ? SVC_FACTOR_PT_LOW :
                                  FACTOR_PT_LOW, FACTOR_PT_HIGH, q,
                                  cpi->common.bit_depth);
       const int bits_per_mb = vp9_rc_bits_per_mb(INTER_FRAME, q,
                                                  factor * speed_term,
                                                  cpi->common.bit_depth);
       if (bits_per_mb <= target_norm_bits_per_mb)
         break;
     }
 
@@ skipping 62 matching lines @@
     while (s < twopass->stats_in_end) {
       modified_error_total += calculate_modified_err(twopass, oxcf, s);
       ++s;
     }
     twopass->modified_error_left = modified_error_total;
   }
 
   // Reset the vbr bits off target counter
   cpi->rc.vbr_bits_off_target = 0;
 
+  cpi->rc.rate_error_estimate = 0;
+
   // Static sequence monitor variables.
   twopass->kf_zeromotion_pct = 100;
   twopass->last_kfgroup_zeromotion_pct = 100;
 }
 
 #define SR_DIFF_PART 0.0015
 #define MOTION_AMP_PART 0.003
 #define INTRA_PART 0.005
 #define DEFAULT_DECAY_LIMIT 0.75
 #define LOW_SR_DIFF_TRHESH 0.1
@@ skipping 114 matching lines @@
                                        mvc_ratio : stats->mvc_abs);
   }
 }
 
 #define BASELINE_ERR_PER_MB 1000.0
 static double calc_frame_boost(VP9_COMP *cpi,
                                const FIRSTPASS_STATS *this_frame,
                                double this_frame_mv_in_out,
                                double max_boost) {
   double frame_boost;
+  const double lq =
+    vp9_convert_qindex_to_q(cpi->rc.avg_frame_qindex[INTER_FRAME],
+                            cpi->common.bit_depth);
+  const double boost_correction = MIN((0.5 + (lq * 0.015)), 1.5);
 
   // Underlying boost factor is based on inter error ratio.
   frame_boost = (BASELINE_ERR_PER_MB * cpi->common.MBs) /
                 DOUBLE_DIVIDE_CHECK(this_frame->coded_error);
-  frame_boost = frame_boost * BOOST_FACTOR;
+  frame_boost = frame_boost * BOOST_FACTOR * boost_correction;
 
   // Increase boost for frames where new data coming into frame (e.g. zoom out).
   // Slightly reduce boost if there is a net balance of motion out of the frame
   // (zoom in). The range for this_frame_mv_in_out is -1.0 to +1.0.
   if (this_frame_mv_in_out > 0.0)
     frame_boost += frame_boost * (this_frame_mv_in_out * 2.0);
   // In the extreme case the boost is halved.
   else
     frame_boost += frame_boost * (this_frame_mv_in_out / 2.0);
 
-  return MIN(frame_boost, max_boost);
+  return MIN(frame_boost, max_boost * boost_correction);
 }
 
 static int calc_arf_boost(VP9_COMP *cpi, int offset,
                           int f_frames, int b_frames,
                           int *f_boost, int *b_boost) {
   TWO_PASS *const twopass = &cpi->twopass;
   int i;
   double boost_score = 0.0;
   double mv_ratio_accumulator = 0.0;
   double decay_accumulator = 1.0;
@@ skipping 68 matching lines @@
 
     boost_score += decay_accumulator * calc_frame_boost(cpi, this_frame,
                                                         this_frame_mv_in_out,
                                                         GF_MAX_BOOST);
   }
   *b_boost = (int)boost_score;
 
   arf_boost = (*f_boost + *b_boost);
   if (arf_boost < ((b_frames + f_frames) * 20))
     arf_boost = ((b_frames + f_frames) * 20);
+  arf_boost = MAX(arf_boost, MIN_ARF_GF_BOOST);
 
   return arf_boost;
 }
 
 // Calculate a section intra ratio used in setting max loop filter.
 static int calculate_section_intra_ratio(const FIRSTPASS_STATS *begin,
                                          const FIRSTPASS_STATS *end,
                                          int section_length) {
   const FIRSTPASS_STATS *s = begin;
   double intra_error = 0.0;
@@ skipping 257 matching lines @@
   double this_frame_mv_in_out = 0.0;
   double mv_in_out_accumulator = 0.0;
   double abs_mv_in_out_accumulator = 0.0;
   double mv_ratio_accumulator_thresh;
   unsigned int allow_alt_ref = is_altref_enabled(cpi);
 
   int f_boost = 0;
   int b_boost = 0;
   int flash_detected;
   int active_max_gf_interval;
+  int active_min_gf_interval;
   int64_t gf_group_bits;
   double gf_group_error_left;
   int gf_arf_bits;
 
   // Reset the GF group data structures unless this is a key
   // frame in which case it will already have been done.
   if (cpi->common.frame_type != KEY_FRAME) {
     vp9_zero(twopass->gf_group);
   }
 
   vp9_clear_system_state();
   vp9_zero(next_frame);
 
   // Load stats for the current frame.
   mod_frame_err = calculate_modified_err(twopass, oxcf, this_frame);
 
   // Note the error of the frame at the start of the group. This will be
   // the GF frame error if we code a normal gf.
   gf_first_frame_err = mod_frame_err;
 
   // If this is a key frame or the overlay from a previous arf then
   // the error score / cost of this frame has already been accounted for.
   if (cpi->common.frame_type == KEY_FRAME || rc->source_alt_ref_active)
     gf_group_err -= gf_first_frame_err;
 
   // Motion breakout threshold for loop below depends on image size.
   mv_ratio_accumulator_thresh = (cpi->common.width + cpi->common.height) / 4.0;
 
-  // Work out a maximum interval for the GF group.
+  // Set a maximum and minimum interval for the GF group.
   // If the image appears almost completely static we can extend beyond this.
-  if (cpi->multi_arf_allowed) {
-    active_max_gf_interval = rc->max_gf_interval;
-  } else {
-   // The value chosen depends on the active Q range. At low Q we have
-   // bits to spare and are better with a smaller interval and smaller boost.
-   // At high Q when there are few bits to spare we are better with a longer
-   // interval to spread the cost of the GF.
-   active_max_gf_interval =
-     12 + ((int)vp9_convert_qindex_to_q(rc->last_q[INTER_FRAME],
-                                        cpi->common.bit_depth) >> 5);
+  {
+    int int_max_q =
+      (int)(vp9_convert_qindex_to_q(twopass->active_worst_quality,
+                                   cpi->common.bit_depth));
+    int int_lbq =
+      (int)(vp9_convert_qindex_to_q(rc->last_boosted_qindex,
+                                   cpi->common.bit_depth));
+    active_min_gf_interval = MIN_GF_INTERVAL + MIN(2, int_max_q / 200);
+    if (active_min_gf_interval > rc->max_gf_interval)
+      active_min_gf_interval = rc->max_gf_interval;
 
-   if (active_max_gf_interval > rc->max_gf_interval)
-     active_max_gf_interval = rc->max_gf_interval;
+    if (cpi->multi_arf_allowed) {
+      active_max_gf_interval = rc->max_gf_interval;
+    } else {
+      // The value chosen depends on the active Q range. At low Q we have
+      // bits to spare and are better with a smaller interval and smaller boost.
+      // At high Q when there are few bits to spare we are better with a longer
+      // interval to spread the cost of the GF.
+      active_max_gf_interval = 12 + MIN(4, (int_lbq / 6));
+      if (active_max_gf_interval > rc->max_gf_interval)
+        active_max_gf_interval = rc->max_gf_interval;
+    }
   }
 
   i = 0;
   while (i < rc->static_scene_max_gf_interval && i < rc->frames_to_key) {
     ++i;
 
     // Accumulate error score of frames in this gf group.
     mod_frame_err = calculate_modified_err(twopass, oxcf, this_frame);
     gf_group_err += mod_frame_err;
 
@@ skipping 35 matching lines @@
     boost_score += decay_accumulator * calc_frame_boost(cpi, &next_frame,
                                                         this_frame_mv_in_out,
                                                         GF_MAX_BOOST);
 
     // Break out conditions.
     if (
       // Break at active_max_gf_interval unless almost totally static.
       (i >= active_max_gf_interval && (zero_motion_accumulator < 0.995)) ||
       (
         // Don't break out with a very short interval.
-        (i > MIN_GF_INTERVAL) &&
+        (i > active_min_gf_interval) &&
         (!flash_detected) &&
         ((mv_ratio_accumulator > mv_ratio_accumulator_thresh) ||
          (abs_mv_in_out_accumulator > 3.0) ||
          (mv_in_out_accumulator < -2.0) ||
-         ((boost_score - old_boost_score) < BOOST_FACTOR)))) {
+         ((boost_score - old_boost_score) < BOOST_BREAKOUT)))) {
       boost_score = old_boost_score;
       break;
     }
 
     *this_frame = next_frame;
     old_boost_score = boost_score;
   }
 
   twopass->gf_zeromotion_pct = (int)(zero_motion_accumulator * 1000.0);
 
@@ skipping 27 matching lines @@
     // Calculate the boost for alt ref.
     rc->gfu_boost = calc_arf_boost(cpi, 0, (i - 1), (i - 1), &f_boost,
                                    &b_boost);
     rc->source_alt_ref_pending = 1;
 
     // Test to see if multi arf is appropriate.
     cpi->multi_arf_enabled =
       (cpi->multi_arf_allowed && (rc->baseline_gf_interval >= 6) &&
       (zero_motion_accumulator < 0.995)) ? 1 : 0;
   } else {
-    rc->gfu_boost = MAX((int)boost_score, 125);
+    rc->gfu_boost = MAX((int)boost_score, MIN_ARF_GF_BOOST);
     rc->source_alt_ref_pending = 0;
   }
 
   // Reset the file position.
   reset_fpf_position(twopass, start_pos);
 
   // Calculate the bits to be allocated to the gf/arf group as a whole
   gf_group_bits = calculate_total_gf_group_bits(cpi, gf_group_err);
 
   // Calculate the extra bits to be used for boosted frame(s)
-  {
-    int q = rc->last_q[INTER_FRAME];
-    int boost =
-        (rc->gfu_boost * gfboost_qadjust(q, cpi->common.bit_depth)) / 100;
-
-    // Set max and minimum boost and hence minimum allocation.
-    boost = clamp(boost, 125, (rc->baseline_gf_interval + 1) * 200);
-
-    // Calculate the extra bits to be used for boosted frame(s)
-    gf_arf_bits = calculate_boost_bits(rc->baseline_gf_interval,
-                                       boost, gf_group_bits);
-  }
+  gf_arf_bits = calculate_boost_bits(rc->baseline_gf_interval,
+                                     rc->gfu_boost, gf_group_bits);
 
   // Adjust KF group bits and error remaining.
   twopass->kf_group_error_left -= (int64_t)gf_group_err;
 
   // If this is an arf update we want to remove the score for the overlay
   // frame at the end which will usually be very cheap to code.
   // The overlay frame has already, in effect, been coded so we want to spread
   // the remaining bits among the other frames.
   // For normal GFs remove the score for the GF itself unless this is
   // also a key frame in which case it has already been accounted for.
@@ skipping 327 matching lines @@
 
   // Note the total error score of the kf group minus the key frame itself.
   twopass->kf_group_error_left = (int)(kf_group_err - kf_mod_err);
 
   // Adjust the count of total modified error left.
   // The count of bits left is adjusted elsewhere based on real coded frame
   // sizes.
   twopass->modified_error_left -= kf_group_err;
 }
 
+#define VBR_PCT_ADJUSTMENT_LIMIT 50
 // For VBR...adjustment to the frame target based on error from previous frames
-void vbr_rate_correction(int * this_frame_target,
+void vbr_rate_correction(VP9_COMP *cpi,
+                         int * this_frame_target,
                          const int64_t vbr_bits_off_target) {
-  int max_delta = (*this_frame_target * 15) / 100;
+  int max_delta;
+  double position_factor = 1.0;
+
+  // How far through the clip are we.
+  // This number is used to damp the per frame rate correction.
+  // Range 0 - 1.0
+  if (cpi->twopass.total_stats.count) {
+    position_factor = sqrt((double)cpi->common.current_video_frame /
+                           cpi->twopass.total_stats.count);
+  }
+  max_delta = (int)(position_factor *
+                    ((*this_frame_target * VBR_PCT_ADJUSTMENT_LIMIT) / 100));
 
   // vbr_bits_off_target > 0 means we have extra bits to spend
   if (vbr_bits_off_target > 0) {
     *this_frame_target +=
       (vbr_bits_off_target > max_delta) ? max_delta
                                         : (int)vbr_bits_off_target;
   } else {
     *this_frame_target -=
       (vbr_bits_off_target < -max_delta) ? max_delta
                                          : (int)-vbr_bits_off_target;
@@ skipping 77 matching lines @@
   // advance the input pointer as we already have what we need.
   if (gf_group->update_type[gf_group->index] == ARF_UPDATE) {
     int target_rate;
     configure_buffer_updates(cpi);
     target_rate = gf_group->bit_allocation[gf_group->index];
     target_rate = vp9_rc_clamp_pframe_target_size(cpi, target_rate);
     rc->base_frame_target = target_rate;
 
     // Correction to rate target based on prior over or under shoot.
     if (cpi->oxcf.rc_mode == VPX_VBR)
-      vbr_rate_correction(&target_rate, rc->vbr_bits_off_target);
+      vbr_rate_correction(cpi, &target_rate, rc->vbr_bits_off_target);
 
     vp9_rc_set_frame_target(cpi, target_rate);
     cm->frame_type = INTER_FRAME;
 
     if (lc != NULL) {
       if (cpi->svc.spatial_layer_id == 0) {
         lc->is_key_frame = 0;
       } else {
         lc->is_key_frame = cpi->svc.layer_context[0].is_key_frame;
 
@@ skipping 11 matching lines @@
     twopass->active_worst_quality = cpi->oxcf.cq_level;
   } else if (cm->current_video_frame == 0 ||
              (lc != NULL && lc->current_video_frame_in_layer == 0)) {
     // Special case code for first frame.
     const int section_target_bandwidth = (int)(twopass->bits_left /
                                                frames_left);
     const int tmp_q = get_twopass_worst_quality(cpi, &twopass->total_left_stats,
                                                 section_target_bandwidth);
     twopass->active_worst_quality = tmp_q;
     rc->ni_av_qi = tmp_q;
+    rc->last_q[INTER_FRAME] = tmp_q;
     rc->avg_q = vp9_convert_qindex_to_q(tmp_q, cm->bit_depth);
+    rc->avg_frame_qindex[INTER_FRAME] = tmp_q;
+    rc->last_q[KEY_FRAME] = (tmp_q + cpi->oxcf.best_allowed_q) / 2;
+    rc->avg_frame_qindex[KEY_FRAME] = rc->last_q[KEY_FRAME];
   }
   vp9_zero(this_frame);
   if (EOF == input_stats(twopass, &this_frame))
     return;
 
   // Local copy of the current frame's first pass stats.
   this_frame_copy = this_frame;
 
   // Keyframe and section processing.
   if (rc->frames_to_key == 0 ||
       (cpi->frame_flags & FRAMEFLAGS_KEY)) {
     // Define next KF group and assign bits to it.
     find_next_key_frame(cpi, &this_frame_copy);
   } else {
     cm->frame_type = INTER_FRAME;
   }
 
   if (lc != NULL) {
     if (cpi->svc.spatial_layer_id == 0) {
       lc->is_key_frame = (cm->frame_type == KEY_FRAME);
       if (lc->is_key_frame) {
         cpi->ref_frame_flags &=
             (~VP9_LAST_FLAG & ~VP9_GOLD_FLAG & ~VP9_ALT_FLAG);
         lc->frames_from_key_frame = 0;
+        // Reset the empty frame resolution since we have a key frame.
+        cpi->svc.empty_frame_width = cm->width;
+        cpi->svc.empty_frame_height = cm->height;
       }
     } else {
       cm->frame_type = INTER_FRAME;
       lc->is_key_frame = cpi->svc.layer_context[0].is_key_frame;
 
       if (lc->is_key_frame) {
         cpi->ref_frame_flags &= (~VP9_LAST_FLAG);
         lc->frames_from_key_frame = 0;
       }
     }
   }
 
   // Define a new GF/ARF group. (Should always enter here for key frames).
   if (rc->frames_till_gf_update_due == 0) {
     define_gf_group(cpi, &this_frame_copy);
 
-    if (twopass->gf_zeromotion_pct > 995) {
-      // As long as max_thresh for encode breakout is small enough, it is ok
-      // to enable it for show frame, i.e. set allow_encode_breakout to
-      // ENCODE_BREAKOUT_LIMITED.
-      if (!cm->show_frame)
-        cpi->allow_encode_breakout = ENCODE_BREAKOUT_DISABLED;
-      else
-        cpi->allow_encode_breakout = ENCODE_BREAKOUT_LIMITED;
-    }
-
     rc->frames_till_gf_update_due = rc->baseline_gf_interval;
     if (lc != NULL)
       cpi->refresh_golden_frame = 1;
 
 #if ARF_STATS_OUTPUT
     {
       FILE *fpfile;
       fpfile = fopen("arf.stt", "a");
       ++arf_count;
-      fprintf(fpfile, "%10d %10d %10d %10ld\n",
-              cm->current_video_frame, rc->kf_boost, arf_count, rc->gfu_boost);
+      fprintf(fpfile, "%10d %10ld %10d %10d %10ld\n",
+              cm->current_video_frame, rc->frames_till_gf_update_due,
+              rc->kf_boost, arf_count, rc->gfu_boost);
 
       fclose(fpfile);
     }
 #endif
   }
 
   configure_buffer_updates(cpi);
 
   target_rate = gf_group->bit_allocation[gf_group->index];
   if (cpi->common.frame_type == KEY_FRAME)
     target_rate = vp9_rc_clamp_iframe_target_size(cpi, target_rate);
   else
     target_rate = vp9_rc_clamp_pframe_target_size(cpi, target_rate);
 
   rc->base_frame_target = target_rate;
 
   // Correction to rate target based on prior over or under shoot.
   if (cpi->oxcf.rc_mode == VPX_VBR)
-    vbr_rate_correction(&target_rate, rc->vbr_bits_off_target);
+    vbr_rate_correction(cpi, &target_rate, rc->vbr_bits_off_target);
 
   vp9_rc_set_frame_target(cpi, target_rate);
 
   // Update the total stats remaining structure.
   subtract_stats(&twopass->total_left_stats, &this_frame);
 }
 
+#define MINQ_ADJ_LIMIT 32
+#define Q_LIMIT_STEP 1
 void vp9_twopass_postencode_update(VP9_COMP *cpi) {
   TWO_PASS *const twopass = &cpi->twopass;
   RATE_CONTROL *const rc = &cpi->rc;
+  const int bits_used = rc->base_frame_target;
 
   // VBR correction is done through rc->vbr_bits_off_target. Based on the
   // sign of this value, a limited % adjustment is made to the target rate
   // of subsequent frames, to try and push it back towards 0. This method
   // is designed to prevent extreme behaviour at the end of a clip
   // or group of frames.
-  const int bits_used = rc->base_frame_target;
   rc->vbr_bits_off_target += rc->base_frame_target - rc->projected_frame_size;
+  twopass->bits_left = MAX(twopass->bits_left - bits_used, 0);
 
-  twopass->bits_left = MAX(twopass->bits_left - bits_used, 0);
+  // Calculate the pct rc error.
+  if (rc->total_actual_bits) {
+    rc->rate_error_estimate =
+      (int)((rc->vbr_bits_off_target * 100) / rc->total_actual_bits);
+    rc->rate_error_estimate = clamp(rc->rate_error_estimate, -100, 100);
+  } else {
+    rc->rate_error_estimate = 0;
+  }
 
   if (cpi->common.frame_type != KEY_FRAME &&
       !vp9_is_upper_layer_key_frame(cpi)) {
     twopass->kf_group_bits -= bits_used;
     twopass->last_kfgroup_zeromotion_pct = twopass->kf_zeromotion_pct;
   }
   twopass->kf_group_bits = MAX(twopass->kf_group_bits, 0);
 
   // Increment the gf group index ready for the next frame.
   ++twopass->gf_group.index;
+
+  // If the rate control is drifting consider adjustment ot min or maxq.
+  // Only make adjustments on gf/arf
+  if ((cpi->oxcf.rc_mode == VPX_VBR) &&
+      (cpi->twopass.gf_zeromotion_pct < VLOW_MOTION_THRESHOLD) &&
+      !cpi->rc.is_src_frame_alt_ref) {
+    const int maxq_adj_limit =
+      rc->worst_quality - twopass->active_worst_quality;
+
+    // Undershoot.
+    if (rc->rate_error_estimate > cpi->oxcf.under_shoot_pct) {
+      --twopass->extend_maxq;
+      if (rc->rolling_target_bits >= rc->rolling_actual_bits)
+        twopass->extend_minq += Q_LIMIT_STEP;
+    // Overshoot.
+    } else if (rc->rate_error_estimate < -cpi->oxcf.over_shoot_pct) {
+      --twopass->extend_minq;
+      if (rc->rolling_target_bits < rc->rolling_actual_bits)
+        twopass->extend_maxq += Q_LIMIT_STEP;
+    } else {
+      if (rc->rolling_target_bits < rc->rolling_actual_bits)
+        --twopass->extend_minq;
+      if (rc->rolling_target_bits > rc->rolling_actual_bits)
+        --twopass->extend_maxq;
+    }
+    twopass->extend_minq = clamp(twopass->extend_minq, 0, MINQ_ADJ_LIMIT);
+    twopass->extend_maxq = clamp(twopass->extend_maxq, 0, maxq_adj_limit);
+  }
 }