Move libvpx from DEPS to src

third_party/libvpx/source/libvpx/vp9/encoder/vp9_ratectrl.c

Index: third_party/libvpx/source/libvpx/vp9/encoder/vp9_ratectrl.c
diff --git a/third_party/libvpx/source/libvpx/vp9/encoder/vp9_ratectrl.c b/third_party/libvpx/source/libvpx/vp9/encoder/vp9_ratectrl.c
new file mode 100644
index 0000000000000000000000000000000000000000..4c33ffd977b588d09c435097da67aa7c3da695cf
--- /dev/null
+++ b/third_party/libvpx/source/libvpx/vp9/encoder/vp9_ratectrl.c
@@ -0,0 +1,1708 @@
+/*
+ *  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.
+ */
+
+#include <assert.h>
+#include <limits.h>
+#include <math.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "vpx_mem/vpx_mem.h"
+
+#include "vp9/common/vp9_alloccommon.h"
+#include "vp9/encoder/vp9_aq_cyclicrefresh.h"
+#include "vp9/common/vp9_common.h"
+#include "vp9/common/vp9_entropymode.h"
+#include "vp9/common/vp9_quant_common.h"
+#include "vp9/common/vp9_seg_common.h"
+#include "vp9/common/vp9_systemdependent.h"
+
+#include "vp9/encoder/vp9_encodemv.h"
+#include "vp9/encoder/vp9_ratectrl.h"
+
+// Max rate target for 1080P and below encodes under normal circumstances
+// (1920 * 1080 / (16 * 16)) * MAX_MB_RATE bits per MB
+#define MAX_MB_RATE 250
+#define MAXRATE_1080P 2025000
+
+#define DEFAULT_KF_BOOST 2000
+#define DEFAULT_GF_BOOST 2000
+
+#define LIMIT_QRANGE_FOR_ALTREF_AND_KEY 1
+
+#define MIN_BPB_FACTOR 0.005
+#define MAX_BPB_FACTOR 50
+
+#define FRAME_OVERHEAD_BITS 200
+
+#if CONFIG_VP9_HIGHBITDEPTH
+#define ASSIGN_MINQ_TABLE(bit_depth, name) \
+  do { \
+    switch (bit_depth) { \
+      case VPX_BITS_8: \
+        name = name##_8; \
+        break; \
+      case VPX_BITS_10: \
+        name = name##_10; \
+        break; \
+      case VPX_BITS_12: \
+        name = name##_12; \
+        break; \
+      default: \
+        assert(0 && "bit_depth should be VPX_BITS_8, VPX_BITS_10" \
+                    " or VPX_BITS_12"); \
+        name = NULL; \
+    } \
+  } while (0)
+#else
+#define ASSIGN_MINQ_TABLE(bit_depth, name) \
+  do { \
+    (void) bit_depth; \
+    name = name##_8; \
+  } while (0)
+#endif
+
+// Tables relating active max Q to active min Q
+static int kf_low_motion_minq_8[QINDEX_RANGE];
+static int kf_high_motion_minq_8[QINDEX_RANGE];
+static int arfgf_low_motion_minq_8[QINDEX_RANGE];
+static int arfgf_high_motion_minq_8[QINDEX_RANGE];
+static int inter_minq_8[QINDEX_RANGE];
+static int rtc_minq_8[QINDEX_RANGE];
+
+#if CONFIG_VP9_HIGHBITDEPTH
+static int kf_low_motion_minq_10[QINDEX_RANGE];
+static int kf_high_motion_minq_10[QINDEX_RANGE];
+static int arfgf_low_motion_minq_10[QINDEX_RANGE];
+static int arfgf_high_motion_minq_10[QINDEX_RANGE];
+static int inter_minq_10[QINDEX_RANGE];
+static int rtc_minq_10[QINDEX_RANGE];
+static int kf_low_motion_minq_12[QINDEX_RANGE];
+static int kf_high_motion_minq_12[QINDEX_RANGE];
+static int arfgf_low_motion_minq_12[QINDEX_RANGE];
+static int arfgf_high_motion_minq_12[QINDEX_RANGE];
+static int inter_minq_12[QINDEX_RANGE];
+static int rtc_minq_12[QINDEX_RANGE];
+#endif
+
+static int gf_high = 2000;
+static int gf_low = 400;
+static int kf_high = 5000;
+static int kf_low = 400;
+
+// Functions to compute the active minq lookup table entries based on a
+// formulaic approach to facilitate easier adjustment of the Q tables.
+// The formulae were derived from computing a 3rd order polynomial best
+// fit to the original data (after plotting real maxq vs minq (not q index))
+static int get_minq_index(double maxq, double x3, double x2, double x1,
+                          vpx_bit_depth_t bit_depth) {
+  int i;
+  const double minqtarget = MIN(((x3 * maxq + x2) * maxq + x1) * maxq,
+                                maxq);
+
+  // Special case handling to deal with the step from q2.0
+  // down to lossless mode represented by q 1.0.
+  if (minqtarget <= 2.0)
+    return 0;
+
+  for (i = 0; i < QINDEX_RANGE; i++) {
+    if (minqtarget <= vp9_convert_qindex_to_q(i, bit_depth))
+      return i;
+  }
+
+  return QINDEX_RANGE - 1;
+}
+
+static void init_minq_luts(int *kf_low_m, int *kf_high_m,
+                           int *arfgf_low, int *arfgf_high,
+                           int *inter, int *rtc, vpx_bit_depth_t bit_depth) {
+  int i;
+  for (i = 0; i < QINDEX_RANGE; i++) {
+    const double maxq = vp9_convert_qindex_to_q(i, bit_depth);
+    kf_low_m[i] = get_minq_index(maxq, 0.000001, -0.0004, 0.150, bit_depth);
+    kf_high_m[i] = get_minq_index(maxq, 0.0000021, -0.00125, 0.55, bit_depth);
+    arfgf_low[i] = get_minq_index(maxq, 0.0000015, -0.0009, 0.30, bit_depth);
+    arfgf_high[i] = get_minq_index(maxq, 0.0000021, -0.00125, 0.55, bit_depth);
+    inter[i] = get_minq_index(maxq, 0.00000271, -0.00113, 0.90, bit_depth);
+    rtc[i] = get_minq_index(maxq, 0.00000271, -0.00113, 0.70, bit_depth);
+  }
+}
+
+void vp9_rc_init_minq_luts() {
+  init_minq_luts(kf_low_motion_minq_8, kf_high_motion_minq_8,
+                 arfgf_low_motion_minq_8, arfgf_high_motion_minq_8,
+                 inter_minq_8, rtc_minq_8, VPX_BITS_8);
+#if CONFIG_VP9_HIGHBITDEPTH
+  init_minq_luts(kf_low_motion_minq_10, kf_high_motion_minq_10,
+                 arfgf_low_motion_minq_10, arfgf_high_motion_minq_10,
+                 inter_minq_10, rtc_minq_10, VPX_BITS_10);
+  init_minq_luts(kf_low_motion_minq_12, kf_high_motion_minq_12,
+                 arfgf_low_motion_minq_12, arfgf_high_motion_minq_12,
+                 inter_minq_12, rtc_minq_12, VPX_BITS_12);
+#endif
+}
+
+// These functions use formulaic calculations to make playing with the
+// quantizer tables easier. If necessary they can be replaced by lookup
+// tables if and when things settle down in the experimental bitstream
+double vp9_convert_qindex_to_q(int qindex, vpx_bit_depth_t bit_depth) {
+  // Convert the index to a real Q value (scaled down to match old Q values)
+#if CONFIG_VP9_HIGHBITDEPTH
+  switch (bit_depth) {
+    case VPX_BITS_8:
+      return vp9_ac_quant(qindex, 0, bit_depth) / 4.0;
+    case VPX_BITS_10:
+      return vp9_ac_quant(qindex, 0, bit_depth) / 16.0;
+    case VPX_BITS_12:
+      return vp9_ac_quant(qindex, 0, bit_depth) / 64.0;
+    default:
+      assert(0 && "bit_depth should be VPX_BITS_8, VPX_BITS_10 or VPX_BITS_12");
+      return -1.0;
+  }
+#else
+  return vp9_ac_quant(qindex, 0, bit_depth) / 4.0;
+#endif
+}
+
+int vp9_rc_bits_per_mb(FRAME_TYPE frame_type, int qindex,
+                       double correction_factor,
+                       vpx_bit_depth_t bit_depth) {
+  const double q = vp9_convert_qindex_to_q(qindex, bit_depth);
+  int enumerator = frame_type == KEY_FRAME ? 2700000 : 1800000;
+
+  assert(correction_factor <= MAX_BPB_FACTOR &&
+         correction_factor >= MIN_BPB_FACTOR);
+
+  // q based adjustment to baseline enumerator
+  enumerator += (int)(enumerator * q) >> 12;
+  return (int)(enumerator * correction_factor / q);
+}
+
+int vp9_estimate_bits_at_q(FRAME_TYPE frame_type, int q, int mbs,
+                           double correction_factor,
+                           vpx_bit_depth_t bit_depth) {
+  const int bpm = (int)(vp9_rc_bits_per_mb(frame_type, q, correction_factor,
+                                           bit_depth));
+  return MAX(FRAME_OVERHEAD_BITS,
+             (int)((uint64_t)bpm * mbs) >> BPER_MB_NORMBITS);
+}
+
+int vp9_rc_clamp_pframe_target_size(const VP9_COMP *const cpi, int target) {
+  const RATE_CONTROL *rc = &cpi->rc;
+  const VP9EncoderConfig *oxcf = &cpi->oxcf;
+  const int min_frame_target = MAX(rc->min_frame_bandwidth,
+                                   rc->avg_frame_bandwidth >> 5);
+  if (target < min_frame_target)
+    target = min_frame_target;
+  if (cpi->refresh_golden_frame && rc->is_src_frame_alt_ref) {
+    // If there is an active ARF at this location use the minimum
+    // bits on this frame even if it is a constructed arf.
+    // The active maximum quantizer insures that an appropriate
+    // number of bits will be spent if needed for constructed ARFs.
+    target = min_frame_target;
+  }
+  // Clip the frame target to the maximum allowed value.
+  if (target > rc->max_frame_bandwidth)
+    target = rc->max_frame_bandwidth;
+  if (oxcf->rc_max_inter_bitrate_pct) {
+    const int max_rate = rc->avg_frame_bandwidth *
+                         oxcf->rc_max_inter_bitrate_pct / 100;
+    target = MIN(target, max_rate);
+  }
+  return target;
+}
+
+int vp9_rc_clamp_iframe_target_size(const VP9_COMP *const cpi, int target) {
+  const RATE_CONTROL *rc = &cpi->rc;
+  const VP9EncoderConfig *oxcf = &cpi->oxcf;
+  if (oxcf->rc_max_intra_bitrate_pct) {
+    const int max_rate = rc->avg_frame_bandwidth *
+                             oxcf->rc_max_intra_bitrate_pct / 100;
+    target = MIN(target, max_rate);
+  }
+  if (target > rc->max_frame_bandwidth)
+    target = rc->max_frame_bandwidth;
+  return target;
+}
+
+// Update the buffer level for higher layers, given the encoded current layer.
+static void update_layer_buffer_level(SVC *svc, int encoded_frame_size) {
+  int temporal_layer = 0;
+  int current_temporal_layer = svc->temporal_layer_id;
+  for (temporal_layer = current_temporal_layer + 1;
+      temporal_layer < svc->number_temporal_layers; ++temporal_layer) {
+    LAYER_CONTEXT *lc = &svc->layer_context[temporal_layer];
+    RATE_CONTROL *lrc = &lc->rc;
+    int bits_off_for_this_layer = (int)(lc->target_bandwidth / lc->framerate -
+        encoded_frame_size);
+    lrc->bits_off_target += bits_off_for_this_layer;
+
+    // Clip buffer level to maximum buffer size for the layer.
+    lrc->bits_off_target = MIN(lrc->bits_off_target, lrc->maximum_buffer_size);
+    lrc->buffer_level = lrc->bits_off_target;
+  }
+}
+
+// Update the buffer level: leaky bucket model.
+static void update_buffer_level(VP9_COMP *cpi, int encoded_frame_size) {
+  const VP9_COMMON *const cm = &cpi->common;
+  RATE_CONTROL *const rc = &cpi->rc;
+
+  // Non-viewable frames are a special case and are treated as pure overhead.
+  if (!cm->show_frame) {
+    rc->bits_off_target -= encoded_frame_size;
+  } else {
+    rc->bits_off_target += rc->avg_frame_bandwidth - encoded_frame_size;
+  }
+
+  // Clip the buffer level to the maximum specified buffer size.
+  rc->bits_off_target = MIN(rc->bits_off_target, rc->maximum_buffer_size);
+  rc->buffer_level = rc->bits_off_target;
+
+  if (cpi->use_svc && cpi->oxcf.rc_mode == VPX_CBR) {
+    update_layer_buffer_level(&cpi->svc, encoded_frame_size);
+  }
+}
+
+void vp9_rc_init(const VP9EncoderConfig *oxcf, int pass, RATE_CONTROL *rc) {
+  int i;
+
+  if (pass == 0 && oxcf->rc_mode == VPX_CBR) {
+    rc->avg_frame_qindex[KEY_FRAME] = oxcf->worst_allowed_q;
+    rc->avg_frame_qindex[INTER_FRAME] = oxcf->worst_allowed_q;
+  } else {
+    rc->avg_frame_qindex[KEY_FRAME] = (oxcf->worst_allowed_q +
+                                           oxcf->best_allowed_q) / 2;
+    rc->avg_frame_qindex[INTER_FRAME] = (oxcf->worst_allowed_q +
+                                           oxcf->best_allowed_q) / 2;
+  }
+
+  rc->last_q[KEY_FRAME] = oxcf->best_allowed_q;
+  rc->last_q[INTER_FRAME] = oxcf->worst_allowed_q;
+
+  rc->buffer_level =    rc->starting_buffer_level;
+  rc->bits_off_target = rc->starting_buffer_level;
+
+  rc->rolling_target_bits      = rc->avg_frame_bandwidth;
+  rc->rolling_actual_bits      = rc->avg_frame_bandwidth;
+  rc->long_rolling_target_bits = rc->avg_frame_bandwidth;
+  rc->long_rolling_actual_bits = rc->avg_frame_bandwidth;
+
+  rc->total_actual_bits = 0;
+  rc->total_target_bits = 0;
+  rc->total_target_vs_actual = 0;
+
+  rc->baseline_gf_interval = DEFAULT_GF_INTERVAL;
+  rc->frames_since_key = 8;  // Sensible default for first frame.
+  rc->this_key_frame_forced = 0;
+  rc->next_key_frame_forced = 0;
+  rc->source_alt_ref_pending = 0;
+  rc->source_alt_ref_active = 0;
+
+  rc->frames_till_gf_update_due = 0;
+  rc->ni_av_qi = oxcf->worst_allowed_q;
+  rc->ni_tot_qi = 0;
+  rc->ni_frames = 0;
+
+  rc->tot_q = 0.0;
+  rc->avg_q = vp9_convert_qindex_to_q(oxcf->worst_allowed_q, oxcf->bit_depth);
+
+  for (i = 0; i < RATE_FACTOR_LEVELS; ++i) {
+    rc->rate_correction_factors[i] = 1.0;
+  }
+}
+
+int vp9_rc_drop_frame(VP9_COMP *cpi) {
+  const VP9EncoderConfig *oxcf = &cpi->oxcf;
+  RATE_CONTROL *const rc = &cpi->rc;
+
+  if (!oxcf->drop_frames_water_mark) {
+    return 0;
+  } else {
+    if (rc->buffer_level < 0) {
+      // Always drop if buffer is below 0.
+      return 1;
+    } else {
+      // If buffer is below drop_mark, for now just drop every other frame
+      // (starting with the next frame) until it increases back over drop_mark.
+      int drop_mark = (int)(oxcf->drop_frames_water_mark *
+          rc->optimal_buffer_level / 100);
+      if ((rc->buffer_level > drop_mark) &&
+          (rc->decimation_factor > 0)) {
+        --rc->decimation_factor;
+      } else if (rc->buffer_level <= drop_mark &&
+          rc->decimation_factor == 0) {
+        rc->decimation_factor = 1;
+      }
+      if (rc->decimation_factor > 0) {
+        if (rc->decimation_count > 0) {
+          --rc->decimation_count;
+          return 1;
+        } else {
+          rc->decimation_count = rc->decimation_factor;
+          return 0;
+        }
+      } else {
+        rc->decimation_count = 0;
+        return 0;
+      }
+    }
+  }
+}
+
+static double get_rate_correction_factor(const VP9_COMP *cpi) {
+  const RATE_CONTROL *const rc = &cpi->rc;
+  double rcf;
+
+  if (cpi->common.frame_type == KEY_FRAME) {
+    rcf = rc->rate_correction_factors[KF_STD];
+  } else if (cpi->oxcf.pass == 2) {
+    RATE_FACTOR_LEVEL rf_lvl =
+      cpi->twopass.gf_group.rf_level[cpi->twopass.gf_group.index];
+    rcf = rc->rate_correction_factors[rf_lvl];
+  } else {
+    if ((cpi->refresh_alt_ref_frame || cpi->refresh_golden_frame) &&
+        !rc->is_src_frame_alt_ref && !cpi->use_svc &&
+        (cpi->oxcf.rc_mode != VPX_CBR || cpi->oxcf.gf_cbr_boost_pct > 20))
+      rcf = rc->rate_correction_factors[GF_ARF_STD];
+    else
+      rcf = rc->rate_correction_factors[INTER_NORMAL];
+  }
+  rcf *= rcf_mult[rc->frame_size_selector];
+  return fclamp(rcf, MIN_BPB_FACTOR, MAX_BPB_FACTOR);
+}
+
+static void set_rate_correction_factor(VP9_COMP *cpi, double factor) {
+  RATE_CONTROL *const rc = &cpi->rc;
+
+  // Normalize RCF to account for the size-dependent scaling factor.
+  factor /= rcf_mult[cpi->rc.frame_size_selector];
+
+  factor = fclamp(factor, MIN_BPB_FACTOR, MAX_BPB_FACTOR);
+
+  if (cpi->common.frame_type == KEY_FRAME) {
+    rc->rate_correction_factors[KF_STD] = factor;
+  } else if (cpi->oxcf.pass == 2) {
+    RATE_FACTOR_LEVEL rf_lvl =
+      cpi->twopass.gf_group.rf_level[cpi->twopass.gf_group.index];
+    rc->rate_correction_factors[rf_lvl] = factor;
+  } else {
+    if ((cpi->refresh_alt_ref_frame || cpi->refresh_golden_frame) &&
+        !rc->is_src_frame_alt_ref && !cpi->use_svc &&
+        (cpi->oxcf.rc_mode != VPX_CBR || cpi->oxcf.gf_cbr_boost_pct > 20))
+      rc->rate_correction_factors[GF_ARF_STD] = factor;
+    else
+      rc->rate_correction_factors[INTER_NORMAL] = factor;
+  }
+}
+
+void vp9_rc_update_rate_correction_factors(VP9_COMP *cpi) {
+  const VP9_COMMON *const cm = &cpi->common;
+  int correction_factor = 100;
+  double rate_correction_factor = get_rate_correction_factor(cpi);
+  double adjustment_limit;
+
+  int projected_size_based_on_q = 0;
+
+  // Do not update the rate factors for arf overlay frames.
+  if (cpi->rc.is_src_frame_alt_ref)
+    return;
+
+  // Clear down mmx registers to allow floating point in what follows
+  vp9_clear_system_state();
+
+  // Work out how big we would have expected the frame to be at this Q given
+  // the current correction factor.
+  // Stay in double to avoid int overflow when values are large
+  if (cpi->oxcf.aq_mode == CYCLIC_REFRESH_AQ && cpi->common.seg.enabled) {
+    projected_size_based_on_q =
+        vp9_cyclic_refresh_estimate_bits_at_q(cpi, rate_correction_factor);
+  } else {
+    projected_size_based_on_q = vp9_estimate_bits_at_q(cpi->common.frame_type,
+                                                       cm->base_qindex,
+                                                       cm->MBs,
+                                                       rate_correction_factor,
+                                                       cm->bit_depth);
+  }
+  // Work out a size correction factor.
+  if (projected_size_based_on_q > FRAME_OVERHEAD_BITS)
+    correction_factor = (int)((100 * (int64_t)cpi->rc.projected_frame_size) /
+                        projected_size_based_on_q);
+
+  // More heavily damped adjustment used if we have been oscillating either side
+  // of target.
+  adjustment_limit = 0.25 +
+      0.5 * MIN(1, fabs(log10(0.01 * correction_factor)));
+
+  cpi->rc.q_2_frame = cpi->rc.q_1_frame;
+  cpi->rc.q_1_frame = cm->base_qindex;
+  cpi->rc.rc_2_frame = cpi->rc.rc_1_frame;
+  if (correction_factor > 110)
+    cpi->rc.rc_1_frame = -1;
+  else if (correction_factor < 90)
+    cpi->rc.rc_1_frame = 1;
+  else
+    cpi->rc.rc_1_frame = 0;
+
+  if (correction_factor > 102) {
+    // We are not already at the worst allowable quality
+    correction_factor = (int)(100 + ((correction_factor - 100) *
+                                  adjustment_limit));
+    rate_correction_factor = (rate_correction_factor * correction_factor) / 100;
+    // Keep rate_correction_factor within limits
+    if (rate_correction_factor > MAX_BPB_FACTOR)
+      rate_correction_factor = MAX_BPB_FACTOR;
+  } else if (correction_factor < 99) {
+    // We are not already at the best allowable quality
+    correction_factor = (int)(100 - ((100 - correction_factor) *
+                                  adjustment_limit));
+    rate_correction_factor = (rate_correction_factor * correction_factor) / 100;
+
+    // Keep rate_correction_factor within limits
+    if (rate_correction_factor < MIN_BPB_FACTOR)
+      rate_correction_factor = MIN_BPB_FACTOR;
+  }
+
+  set_rate_correction_factor(cpi, rate_correction_factor);
+}
+
+
+int vp9_rc_regulate_q(const VP9_COMP *cpi, int target_bits_per_frame,
+                      int active_best_quality, int active_worst_quality) {
+  const VP9_COMMON *const cm = &cpi->common;
+  int q = active_worst_quality;
+  int last_error = INT_MAX;
+  int i, target_bits_per_mb, bits_per_mb_at_this_q;
+  const double correction_factor = get_rate_correction_factor(cpi);
+
+  // Calculate required scaling factor based on target frame size and size of
+  // frame produced using previous Q.
+  target_bits_per_mb =
+      ((uint64_t)target_bits_per_frame << BPER_MB_NORMBITS) / cm->MBs;
+
+  i = active_best_quality;
+
+  do {
+    if (cpi->oxcf.aq_mode == CYCLIC_REFRESH_AQ && cm->seg.enabled) {
+      bits_per_mb_at_this_q =
+          (int)vp9_cyclic_refresh_rc_bits_per_mb(cpi, i, correction_factor);
+    } else {
+      bits_per_mb_at_this_q = (int)vp9_rc_bits_per_mb(cm->frame_type, i,
+                                                      correction_factor,
+                                                      cm->bit_depth);
+    }
+
+    if (bits_per_mb_at_this_q <= target_bits_per_mb) {
+      if ((target_bits_per_mb - bits_per_mb_at_this_q) <= last_error)
+        q = i;
+      else
+        q = i - 1;
+
+      break;
+    } else {
+      last_error = bits_per_mb_at_this_q - target_bits_per_mb;
+    }
+  } while (++i <= active_worst_quality);
+
+  // In CBR mode, this makes sure q is between oscillating Qs to prevent
+  // resonance.
+  if (cpi->oxcf.rc_mode == VPX_CBR &&
+      (cpi->rc.rc_1_frame * cpi->rc.rc_2_frame == -1) &&
+      cpi->rc.q_1_frame != cpi->rc.q_2_frame) {
+    q = clamp(q, MIN(cpi->rc.q_1_frame, cpi->rc.q_2_frame),
+              MAX(cpi->rc.q_1_frame, cpi->rc.q_2_frame));
+  }
+  return q;
+}
+
+static int get_active_quality(int q, int gfu_boost, int low, int high,
+                              int *low_motion_minq, int *high_motion_minq) {
+  if (gfu_boost > high) {
+    return low_motion_minq[q];
+  } else if (gfu_boost < low) {
+    return high_motion_minq[q];
+  } else {
+    const int gap = high - low;
+    const int offset = high - gfu_boost;
+    const int qdiff = high_motion_minq[q] - low_motion_minq[q];
+    const int adjustment = ((offset * qdiff) + (gap >> 1)) / gap;
+    return low_motion_minq[q] + adjustment;
+  }
+}
+
+static int get_kf_active_quality(const RATE_CONTROL *const rc, int q,
+                                 vpx_bit_depth_t bit_depth) {
+  int *kf_low_motion_minq;
+  int *kf_high_motion_minq;
+  ASSIGN_MINQ_TABLE(bit_depth, kf_low_motion_minq);
+  ASSIGN_MINQ_TABLE(bit_depth, kf_high_motion_minq);
+  return get_active_quality(q, rc->kf_boost, kf_low, kf_high,
+                            kf_low_motion_minq, kf_high_motion_minq);
+}
+
+static int get_gf_active_quality(const RATE_CONTROL *const rc, int q,
+                                 vpx_bit_depth_t bit_depth) {
+  int *arfgf_low_motion_minq;
+  int *arfgf_high_motion_minq;
+  ASSIGN_MINQ_TABLE(bit_depth, arfgf_low_motion_minq);
+  ASSIGN_MINQ_TABLE(bit_depth, arfgf_high_motion_minq);
+  return get_active_quality(q, rc->gfu_boost, gf_low, gf_high,
+                            arfgf_low_motion_minq, arfgf_high_motion_minq);
+}
+
+static int calc_active_worst_quality_one_pass_vbr(const VP9_COMP *cpi) {
+  const RATE_CONTROL *const rc = &cpi->rc;
+  const unsigned int curr_frame = cpi->common.current_video_frame;
+  int active_worst_quality;
+
+  if (cpi->common.frame_type == KEY_FRAME) {
+    active_worst_quality = curr_frame == 0 ? rc->worst_quality
+                                           : rc->last_q[KEY_FRAME] * 2;
+  } else {
+    if (!rc->is_src_frame_alt_ref &&
+        (cpi->refresh_golden_frame || cpi->refresh_alt_ref_frame)) {
+      active_worst_quality =  curr_frame == 1 ? rc->last_q[KEY_FRAME] * 5 / 4
+                                              : rc->last_q[INTER_FRAME];
+    } else {
+      active_worst_quality = curr_frame == 1 ? rc->last_q[KEY_FRAME] * 2
+                                             : rc->last_q[INTER_FRAME] * 2;
+    }
+  }
+  return MIN(active_worst_quality, rc->worst_quality);
+}
+
+// Adjust active_worst_quality level based on buffer level.
+static int calc_active_worst_quality_one_pass_cbr(const VP9_COMP *cpi) {
+  // Adjust active_worst_quality: If buffer is above the optimal/target level,
+  // bring active_worst_quality down depending on fullness of buffer.
+  // If buffer is below the optimal level, let the active_worst_quality go from
+  // ambient Q (at buffer = optimal level) to worst_quality level
+  // (at buffer = critical level).
+  const VP9_COMMON *const cm = &cpi->common;
+  const RATE_CONTROL *rc = &cpi->rc;
+  // Buffer level below which we push active_worst to worst_quality.
+  int64_t critical_level = rc->optimal_buffer_level >> 3;
+  int64_t buff_lvl_step = 0;
+  int adjustment = 0;
+  int active_worst_quality;
+  int ambient_qp;
+  if (cm->frame_type == KEY_FRAME)
+    return rc->worst_quality;
+  // For ambient_qp we use minimum of avg_frame_qindex[KEY_FRAME/INTER_FRAME]
+  // for the first few frames following key frame. These are both initialized
+  // to worst_quality and updated with (3/4, 1/4) average in postencode_update.
+  // So for first few frames following key, the qp of that key frame is weighted
+  // into the active_worst_quality setting.
+  ambient_qp = (cm->current_video_frame < 5) ?
+      MIN(rc->avg_frame_qindex[INTER_FRAME], rc->avg_frame_qindex[KEY_FRAME]) :
+      rc->avg_frame_qindex[INTER_FRAME];
+  active_worst_quality = MIN(rc->worst_quality,
+                             ambient_qp * 5 / 4);
+  if (rc->buffer_level > rc->optimal_buffer_level) {
+    // Adjust down.
+    // Maximum limit for down adjustment, ~30%.
+    int max_adjustment_down = active_worst_quality / 3;
+    if (max_adjustment_down) {
+      buff_lvl_step = ((rc->maximum_buffer_size -
+                        rc->optimal_buffer_level) / max_adjustment_down);
+      if (buff_lvl_step)
+        adjustment = (int)((rc->buffer_level - rc->optimal_buffer_level) /
+                            buff_lvl_step);
+      active_worst_quality -= adjustment;
+    }
+  } else if (rc->buffer_level > critical_level) {
+    // Adjust up from ambient Q.
+    if (critical_level) {
+      buff_lvl_step = (rc->optimal_buffer_level - critical_level);
+      if (buff_lvl_step) {
+        adjustment = (int)((rc->worst_quality - ambient_qp) *
+                           (rc->optimal_buffer_level - rc->buffer_level) /
+                           buff_lvl_step);
+      }
+      active_worst_quality = ambient_qp + adjustment;
+    }
+  } else {
+    // Set to worst_quality if buffer is below critical level.
+    active_worst_quality = rc->worst_quality;
+  }
+  return active_worst_quality;
+}
+
+static int rc_pick_q_and_bounds_one_pass_cbr(const VP9_COMP *cpi,
+                                             int *bottom_index,
+                                             int *top_index) {
+  const VP9_COMMON *const cm = &cpi->common;
+  const RATE_CONTROL *const rc = &cpi->rc;
+  int active_best_quality;
+  int active_worst_quality = calc_active_worst_quality_one_pass_cbr(cpi);
+  int q;
+  int *rtc_minq;
+  ASSIGN_MINQ_TABLE(cm->bit_depth, rtc_minq);
+
+  if (frame_is_intra_only(cm)) {
+    active_best_quality = rc->best_quality;
+    // Handle the special case for key frames forced when we have reached
+    // the maximum key frame interval. Here force the Q to a range
+    // based on the ambient Q to reduce the risk of popping.
+    if (rc->this_key_frame_forced) {
+      int qindex = rc->last_boosted_qindex;
+      double last_boosted_q = vp9_convert_qindex_to_q(qindex, cm->bit_depth);
+      int delta_qindex = vp9_compute_qdelta(rc, last_boosted_q,
+                                            (last_boosted_q * 0.75),
+                                            cm->bit_depth);
+      active_best_quality = MAX(qindex + delta_qindex, rc->best_quality);
+    } else if (cm->current_video_frame > 0) {
+      // not first frame of one pass and kf_boost is set
+      double q_adj_factor = 1.0;
+      double q_val;
+
+      active_best_quality =
+          get_kf_active_quality(rc, rc->avg_frame_qindex[KEY_FRAME],
+                                cm->bit_depth);
+
+      // Allow somewhat lower kf minq with small image formats.
+      if ((cm->width * cm->height) <= (352 * 288)) {
+        q_adj_factor -= 0.25;
+      }
+
+      // Convert the adjustment factor to a qindex delta
+      // on active_best_quality.
+      q_val = vp9_convert_qindex_to_q(active_best_quality, cm->bit_depth);
+      active_best_quality += vp9_compute_qdelta(rc, q_val,
+                                                q_val * q_adj_factor,
+                                                cm->bit_depth);
+    }
+  } else if (!rc->is_src_frame_alt_ref &&
+             !cpi->use_svc &&
+             (cpi->refresh_golden_frame || cpi->refresh_alt_ref_frame)) {
+    // Use the lower of active_worst_quality and recent
+    // average Q as basis for GF/ARF best Q limit unless last frame was
+    // a key frame.
+    if (rc->frames_since_key > 1 &&
+        rc->avg_frame_qindex[INTER_FRAME] < active_worst_quality) {
+      q = rc->avg_frame_qindex[INTER_FRAME];
+    } else {
+      q = active_worst_quality;
+    }
+    active_best_quality = get_gf_active_quality(rc, q, cm->bit_depth);
+  } else {
+    // Use the lower of active_worst_quality and recent/average Q.
+    if (cm->current_video_frame > 1) {
+      if (rc->avg_frame_qindex[INTER_FRAME] < active_worst_quality)
+        active_best_quality = rtc_minq[rc->avg_frame_qindex[INTER_FRAME]];
+      else
+        active_best_quality = rtc_minq[active_worst_quality];
+    } else {
+      if (rc->avg_frame_qindex[KEY_FRAME] < active_worst_quality)
+        active_best_quality = rtc_minq[rc->avg_frame_qindex[KEY_FRAME]];
+      else
+        active_best_quality = rtc_minq[active_worst_quality];
+    }
+  }
+
+  // Clip the active best and worst quality values to limits
+  active_best_quality = clamp(active_best_quality,
+                              rc->best_quality, rc->worst_quality);
+  active_worst_quality = clamp(active_worst_quality,
+                               active_best_quality, rc->worst_quality);
+
+  *top_index = active_worst_quality;
+  *bottom_index = active_best_quality;
+
+#if LIMIT_QRANGE_FOR_ALTREF_AND_KEY
+  // Limit Q range for the adaptive loop.
+  if (cm->frame_type == KEY_FRAME &&
+      !rc->this_key_frame_forced  &&
+      !(cm->current_video_frame == 0)) {
+    int qdelta = 0;
+    vp9_clear_system_state();
+    qdelta = vp9_compute_qdelta_by_rate(&cpi->rc, cm->frame_type,
+                                        active_worst_quality, 2.0,
+                                        cm->bit_depth);
+    *top_index = active_worst_quality + qdelta;
+    *top_index = (*top_index > *bottom_index) ? *top_index : *bottom_index;
+  }
+#endif
+
+  // Special case code to try and match quality with forced key frames
+  if (cm->frame_type == KEY_FRAME && rc->this_key_frame_forced) {
+    q = rc->last_boosted_qindex;
+  } else {
+    q = vp9_rc_regulate_q(cpi, rc->this_frame_target,
+                          active_best_quality, active_worst_quality);
+    if (q > *top_index) {
+      // Special case when we are targeting the max allowed rate
+      if (rc->this_frame_target >= rc->max_frame_bandwidth)
+        *top_index = q;
+      else
+        q = *top_index;
+    }
+  }
+  assert(*top_index <= rc->worst_quality &&
+         *top_index >= rc->best_quality);
+  assert(*bottom_index <= rc->worst_quality &&
+         *bottom_index >= rc->best_quality);
+  assert(q <= rc->worst_quality && q >= rc->best_quality);
+  return q;
+}
+
+static int get_active_cq_level(const RATE_CONTROL *rc,
+                               const VP9EncoderConfig *const oxcf) {
+  static const double cq_adjust_threshold = 0.1;
+  int active_cq_level = oxcf->cq_level;
+  if (oxcf->rc_mode == VPX_CQ &&
+      rc->total_target_bits > 0) {
+    const double x = (double)rc->total_actual_bits / rc->total_target_bits;
+    if (x < cq_adjust_threshold) {
+      active_cq_level = (int)(active_cq_level * x / cq_adjust_threshold);
+    }
+  }
+  return active_cq_level;
+}
+
+static int rc_pick_q_and_bounds_one_pass_vbr(const VP9_COMP *cpi,
+                                             int *bottom_index,
+                                             int *top_index) {
+  const VP9_COMMON *const cm = &cpi->common;
+  const RATE_CONTROL *const rc = &cpi->rc;
+  const VP9EncoderConfig *const oxcf = &cpi->oxcf;
+  const int cq_level = get_active_cq_level(rc, oxcf);
+  int active_best_quality;
+  int active_worst_quality = calc_active_worst_quality_one_pass_vbr(cpi);
+  int q;
+  int *inter_minq;
+  ASSIGN_MINQ_TABLE(cm->bit_depth, inter_minq);
+
+  if (frame_is_intra_only(cm)) {
+
+    // Handle the special case for key frames forced when we have reached
+    // the maximum key frame interval. Here force the Q to a range
+    // based on the ambient Q to reduce the risk of popping.
+    if (rc->this_key_frame_forced) {
+      int qindex = rc->last_boosted_qindex;
+      double last_boosted_q = vp9_convert_qindex_to_q(qindex, cm->bit_depth);
+      int delta_qindex = vp9_compute_qdelta(rc, last_boosted_q,
+                                            last_boosted_q * 0.75,
+                                            cm->bit_depth);
+      active_best_quality = MAX(qindex + delta_qindex, rc->best_quality);
+    } else {
+      // not first frame of one pass and kf_boost is set
+      double q_adj_factor = 1.0;
+      double q_val;
+
+      active_best_quality =
+          get_kf_active_quality(rc, rc->avg_frame_qindex[KEY_FRAME],
+                                cm->bit_depth);
+
+      // Allow somewhat lower kf minq with small image formats.
+      if ((cm->width * cm->height) <= (352 * 288)) {
+        q_adj_factor -= 0.25;
+      }
+
+      // Convert the adjustment factor to a qindex delta
+      // on active_best_quality.
+      q_val = vp9_convert_qindex_to_q(active_best_quality, cm->bit_depth);
+      active_best_quality += vp9_compute_qdelta(rc, q_val,
+                                                q_val * q_adj_factor,
+                                                cm->bit_depth);
+    }
+  } else if (!rc->is_src_frame_alt_ref &&
+             (cpi->refresh_golden_frame || cpi->refresh_alt_ref_frame)) {
+    // Use the lower of active_worst_quality and recent
+    // average Q as basis for GF/ARF best Q limit unless last frame was
+    // a key frame.
+    if (rc->frames_since_key > 1 &&
+        rc->avg_frame_qindex[INTER_FRAME] < active_worst_quality) {
+      q = rc->avg_frame_qindex[INTER_FRAME];
+    } else {
+      q = rc->avg_frame_qindex[KEY_FRAME];
+    }
+    // For constrained quality dont allow Q less than the cq level
+    if (oxcf->rc_mode == VPX_CQ) {
+      if (q < cq_level)
+        q = cq_level;
+
+      active_best_quality = get_gf_active_quality(rc, q, cm->bit_depth);
+
+      // Constrained quality use slightly lower active best.
+      active_best_quality = active_best_quality * 15 / 16;
+
+    } else if (oxcf->rc_mode == VPX_Q) {
+      if (!cpi->refresh_alt_ref_frame) {
+        active_best_quality = cq_level;
+      } else {
+        active_best_quality = get_gf_active_quality(rc, q, cm->bit_depth);
+      }
+    } else {
+      active_best_quality = get_gf_active_quality(rc, q, cm->bit_depth);
+    }
+  } else {
+    if (oxcf->rc_mode == VPX_Q) {
+      active_best_quality = cq_level;
+    } else {
+      // Use the lower of active_worst_quality and recent/average Q.
+      if (cm->current_video_frame > 1)
+        active_best_quality = inter_minq[rc->avg_frame_qindex[INTER_FRAME]];
+      else
+        active_best_quality = inter_minq[rc->avg_frame_qindex[KEY_FRAME]];
+      // For the constrained quality mode we don't want
+      // q to fall below the cq level.
+      if ((oxcf->rc_mode == VPX_CQ) &&
+          (active_best_quality < cq_level)) {
+        active_best_quality = cq_level;
+      }
+    }
+  }
+
+  // Clip the active best and worst quality values to limits
+  active_best_quality = clamp(active_best_quality,
+                              rc->best_quality, rc->worst_quality);
+  active_worst_quality = clamp(active_worst_quality,
+                               active_best_quality, rc->worst_quality);
+
+  *top_index = active_worst_quality;
+  *bottom_index = active_best_quality;
+
+#if LIMIT_QRANGE_FOR_ALTREF_AND_KEY
+  {
+    int qdelta = 0;
+    vp9_clear_system_state();
+
+    // Limit Q range for the adaptive loop.
+    if (cm->frame_type == KEY_FRAME &&
+        !rc->this_key_frame_forced &&
+        !(cm->current_video_frame == 0)) {
+      qdelta = vp9_compute_qdelta_by_rate(&cpi->rc, cm->frame_type,
+                                          active_worst_quality, 2.0,
+                                          cm->bit_depth);
+    } else if (!rc->is_src_frame_alt_ref &&
+               (cpi->refresh_golden_frame || cpi->refresh_alt_ref_frame)) {
+      qdelta = vp9_compute_qdelta_by_rate(&cpi->rc, cm->frame_type,
+                                          active_worst_quality, 1.75,
+                                          cm->bit_depth);
+    }
+    *top_index = active_worst_quality + qdelta;
+    *top_index = (*top_index > *bottom_index) ? *top_index : *bottom_index;
+  }
+#endif
+
+  if (oxcf->rc_mode == VPX_Q) {
+    q = active_best_quality;
+  // Special case code to try and match quality with forced key frames
+  } else if ((cm->frame_type == KEY_FRAME) && rc->this_key_frame_forced) {
+    q = rc->last_boosted_qindex;
+  } else {
+    q = vp9_rc_regulate_q(cpi, rc->this_frame_target,
+                          active_best_quality, active_worst_quality);
+    if (q > *top_index) {
+      // Special case when we are targeting the max allowed rate
+      if (rc->this_frame_target >= rc->max_frame_bandwidth)
+        *top_index = q;
+      else
+        q = *top_index;
+    }
+  }
+
+  assert(*top_index <= rc->worst_quality &&
+         *top_index >= rc->best_quality);
+  assert(*bottom_index <= rc->worst_quality &&
+         *bottom_index >= rc->best_quality);
+  assert(q <= rc->worst_quality && q >= rc->best_quality);
+  return q;
+}
+
+int vp9_frame_type_qdelta(const VP9_COMP *cpi, int rf_level, int q) {
+  static const double rate_factor_deltas[RATE_FACTOR_LEVELS] = {
+    1.00,  // INTER_NORMAL
+    1.00,  // INTER_HIGH
+    1.50,  // GF_ARF_LOW
+    1.75,  // GF_ARF_STD
+    2.00,  // KF_STD
+  };
+  static const FRAME_TYPE frame_type[RATE_FACTOR_LEVELS] =
+      {INTER_FRAME, INTER_FRAME, INTER_FRAME, INTER_FRAME, KEY_FRAME};
+  const VP9_COMMON *const cm = &cpi->common;
+  int qdelta = vp9_compute_qdelta_by_rate(&cpi->rc, frame_type[rf_level],
+                                          q, rate_factor_deltas[rf_level],
+                                          cm->bit_depth);
+  return qdelta;
+}
+
+#define STATIC_MOTION_THRESH 95
+static int rc_pick_q_and_bounds_two_pass(const VP9_COMP *cpi,
+                                         int *bottom_index,
+                                         int *top_index) {
+  const VP9_COMMON *const cm = &cpi->common;
+  const RATE_CONTROL *const rc = &cpi->rc;
+  const VP9EncoderConfig *const oxcf = &cpi->oxcf;
+  const GF_GROUP *gf_group = &cpi->twopass.gf_group;
+  const int cq_level = get_active_cq_level(rc, oxcf);
+  int active_best_quality;
+  int active_worst_quality = cpi->twopass.active_worst_quality;
+  int q;
+  int *inter_minq;
+  ASSIGN_MINQ_TABLE(cm->bit_depth, inter_minq);
+
+  if (frame_is_intra_only(cm) || vp9_is_upper_layer_key_frame(cpi)) {
+    // Handle the special case for key frames forced when we have reached
+    // the maximum key frame interval. Here force the Q to a range
+    // based on the ambient Q to reduce the risk of popping.
+    if (rc->this_key_frame_forced) {
+      double last_boosted_q;
+      int delta_qindex;
+      int qindex;
+
+      if (cpi->twopass.last_kfgroup_zeromotion_pct >= STATIC_MOTION_THRESH) {
+        qindex = MIN(rc->last_kf_qindex, rc->last_boosted_qindex);
+        active_best_quality = qindex;
+        last_boosted_q = vp9_convert_qindex_to_q(qindex, cm->bit_depth);
+        delta_qindex = vp9_compute_qdelta(rc, last_boosted_q,
+                                              last_boosted_q * 1.25,
+                                              cm->bit_depth);
+        active_worst_quality = MIN(qindex + delta_qindex, active_worst_quality);
+
+      } else {
+        qindex = rc->last_boosted_qindex;
+        last_boosted_q = vp9_convert_qindex_to_q(qindex, cm->bit_depth);
+        delta_qindex = vp9_compute_qdelta(rc, last_boosted_q,
+                                              last_boosted_q * 0.75,
+                                              cm->bit_depth);
+        active_best_quality = MAX(qindex + delta_qindex, rc->best_quality);
+      }
+    } else {
+      // Not forced keyframe.
+      double q_adj_factor = 1.0;
+      double q_val;
+      // Baseline value derived from cpi->active_worst_quality and kf boost.
+      active_best_quality = get_kf_active_quality(rc, active_worst_quality,
+                                                  cm->bit_depth);
+
+      // Allow somewhat lower kf minq with small image formats.
+      if ((cm->width * cm->height) <= (352 * 288)) {
+        q_adj_factor -= 0.25;
+      }
+
+      // Make a further adjustment based on the kf zero motion measure.
+      q_adj_factor += 0.05 - (0.001 * (double)cpi->twopass.kf_zeromotion_pct);
+
+      // Convert the adjustment factor to a qindex delta
+      // on active_best_quality.
+      q_val = vp9_convert_qindex_to_q(active_best_quality, cm->bit_depth);
+      active_best_quality += vp9_compute_qdelta(rc, q_val,
+                                                q_val * q_adj_factor,
+                                                cm->bit_depth);
+    }
+  } else if (!rc->is_src_frame_alt_ref &&
+             (cpi->refresh_golden_frame || cpi->refresh_alt_ref_frame)) {
+    // Use the lower of active_worst_quality and recent
+    // average Q as basis for GF/ARF best Q limit unless last frame was
+    // a key frame.
+    if (rc->frames_since_key > 1 &&
+        rc->avg_frame_qindex[INTER_FRAME] < active_worst_quality) {
+      q = rc->avg_frame_qindex[INTER_FRAME];
+    } else {
+      q = active_worst_quality;
+    }
+    // For constrained quality dont allow Q less than the cq level
+    if (oxcf->rc_mode == VPX_CQ) {
+      if (q < cq_level)
+        q = cq_level;
+
+      active_best_quality = get_gf_active_quality(rc, q, cm->bit_depth);
+
+      // Constrained quality use slightly lower active best.
+      active_best_quality = active_best_quality * 15 / 16;
+
+    } else if (oxcf->rc_mode == VPX_Q) {
+      if (!cpi->refresh_alt_ref_frame) {
+        active_best_quality = cq_level;
+      } else {
+       active_best_quality = get_gf_active_quality(rc, q, cm->bit_depth);
+
+        // Modify best quality for second level arfs. For mode VPX_Q this
+        // becomes the baseline frame q.
+        if (gf_group->rf_level[gf_group->index] == GF_ARF_LOW)
+          active_best_quality = (active_best_quality + cq_level + 1) / 2;
+      }
+    } else {
+      active_best_quality = get_gf_active_quality(rc, q, cm->bit_depth);
+    }
+  } else {
+    if (oxcf->rc_mode == VPX_Q) {
+      active_best_quality = cq_level;
+    } else {
+      active_best_quality = inter_minq[active_worst_quality];
+
+      // For the constrained quality mode we don't want
+      // q to fall below the cq level.
+      if ((oxcf->rc_mode == VPX_CQ) &&
+          (active_best_quality < cq_level)) {
+        active_best_quality = cq_level;
+      }
+    }
+  }
+
+  // Extension to max or min Q if undershoot or overshoot is outside
+  // the permitted range.
+  if ((cpi->oxcf.rc_mode != VPX_Q) &&
+      (cpi->twopass.gf_zeromotion_pct < VLOW_MOTION_THRESHOLD)) {
+    if (frame_is_intra_only(cm) ||
+        (!rc->is_src_frame_alt_ref &&
+         (cpi->refresh_golden_frame || cpi->refresh_alt_ref_frame))) {
+      active_best_quality -= cpi->twopass.extend_minq;
+      active_worst_quality += (cpi->twopass.extend_maxq / 2);
+    } else {
+      active_best_quality -= cpi->twopass.extend_minq / 2;
+      active_worst_quality += cpi->twopass.extend_maxq;
+    }
+  }
+
+#if LIMIT_QRANGE_FOR_ALTREF_AND_KEY
+  vp9_clear_system_state();
+  // Static forced key frames Q restrictions dealt with elsewhere.
+  if (!((frame_is_intra_only(cm) || vp9_is_upper_layer_key_frame(cpi))) ||
+      !rc->this_key_frame_forced ||
+      (cpi->twopass.last_kfgroup_zeromotion_pct < STATIC_MOTION_THRESH)) {
+    int qdelta = vp9_frame_type_qdelta(cpi, gf_group->rf_level[gf_group->index],
+                                       active_worst_quality);
+    active_worst_quality = MAX(active_worst_quality + qdelta,
+                               active_best_quality);
+  }
+#endif
+
+  // Modify active_best_quality for downscaled normal frames.
+  if (rc->frame_size_selector != UNSCALED && !frame_is_kf_gf_arf(cpi)) {
+    int qdelta = vp9_compute_qdelta_by_rate(rc, cm->frame_type,
+                                            active_best_quality, 2.0,
+                                            cm->bit_depth);
+    active_best_quality = MAX(active_best_quality + qdelta, rc->best_quality);
+  }
+
+  active_best_quality = clamp(active_best_quality,
+                              rc->best_quality, rc->worst_quality);
+  active_worst_quality = clamp(active_worst_quality,
+                               active_best_quality, rc->worst_quality);
+
+  if (oxcf->rc_mode == VPX_Q) {
+    q = active_best_quality;
+  // Special case code to try and match quality with forced key frames.
+  } else if ((frame_is_intra_only(cm) || vp9_is_upper_layer_key_frame(cpi)) &&
+             rc->this_key_frame_forced) {
+    // If static since last kf use better of last boosted and last kf q.
+    if (cpi->twopass.last_kfgroup_zeromotion_pct >= STATIC_MOTION_THRESH) {
+      q = MIN(rc->last_kf_qindex, rc->last_boosted_qindex);
+    } else {
+      q = rc->last_boosted_qindex;
+    }
+  } else {
+    q = vp9_rc_regulate_q(cpi, rc->this_frame_target,
+                          active_best_quality, active_worst_quality);
+    if (q > active_worst_quality) {
+      // Special case when we are targeting the max allowed rate.
+      if (rc->this_frame_target >= rc->max_frame_bandwidth)
+        active_worst_quality = q;
+      else
+        q = active_worst_quality;
+    }
+  }
+  clamp(q, active_best_quality, active_worst_quality);
+
+  *top_index = active_worst_quality;
+  *bottom_index = active_best_quality;
+
+  assert(*top_index <= rc->worst_quality &&
+         *top_index >= rc->best_quality);
+  assert(*bottom_index <= rc->worst_quality &&
+         *bottom_index >= rc->best_quality);
+  assert(q <= rc->worst_quality && q >= rc->best_quality);
+  return q;
+}
+
+int vp9_rc_pick_q_and_bounds(const VP9_COMP *cpi,
+                             int *bottom_index, int *top_index) {
+  int q;
+  if (cpi->oxcf.pass == 0) {
+    if (cpi->oxcf.rc_mode == VPX_CBR)
+      q = rc_pick_q_and_bounds_one_pass_cbr(cpi, bottom_index, top_index);
+    else
+      q = rc_pick_q_and_bounds_one_pass_vbr(cpi, bottom_index, top_index);
+  } else {
+    q = rc_pick_q_and_bounds_two_pass(cpi, bottom_index, top_index);
+  }
+  if (cpi->sf.use_nonrd_pick_mode) {
+    if (cpi->sf.force_frame_boost == 1)
+      q -= cpi->sf.max_delta_qindex;
+
+    if (q < *bottom_index)
+      *bottom_index = q;
+    else if (q > *top_index)
+      *top_index = q;
+  }
+  return q;
+}
+
+void vp9_rc_compute_frame_size_bounds(const VP9_COMP *cpi,
+                                      int frame_target,
+                                      int *frame_under_shoot_limit,
+                                      int *frame_over_shoot_limit) {
+  if (cpi->oxcf.rc_mode == VPX_Q) {
+    *frame_under_shoot_limit = 0;
+    *frame_over_shoot_limit  = INT_MAX;
+  } else {
+    // For very small rate targets where the fractional adjustment
+    // may be tiny make sure there is at least a minimum range.
+    const int tolerance = (cpi->sf.recode_tolerance * frame_target) / 100;
+    *frame_under_shoot_limit = MAX(frame_target - tolerance - 200, 0);
+    *frame_over_shoot_limit = MIN(frame_target + tolerance + 200,
+                                  cpi->rc.max_frame_bandwidth);
+  }
+}
+
+void vp9_rc_set_frame_target(VP9_COMP *cpi, int target) {
+  const VP9_COMMON *const cm = &cpi->common;
+  RATE_CONTROL *const rc = &cpi->rc;
+
+  rc->this_frame_target = target;
+
+  // Modify frame size target when down-scaling.
+  if (cpi->oxcf.resize_mode == RESIZE_DYNAMIC &&
+      rc->frame_size_selector != UNSCALED)
+    rc->this_frame_target = (int)(rc->this_frame_target
+        * rate_thresh_mult[rc->frame_size_selector]);
+
+  // Target rate per SB64 (including partial SB64s.
+  rc->sb64_target_rate = ((int64_t)rc->this_frame_target * 64 * 64) /
+                             (cm->width * cm->height);
+}
+
+static void update_alt_ref_frame_stats(VP9_COMP *cpi) {
+  // this frame refreshes means next frames don't unless specified by user
+  RATE_CONTROL *const rc = &cpi->rc;
+  rc->frames_since_golden = 0;
+
+  // Mark the alt ref as done (setting to 0 means no further alt refs pending).
+  rc->source_alt_ref_pending = 0;
+
+  // Set the alternate reference frame active flag
+  rc->source_alt_ref_active = 1;
+}
+
+static void update_golden_frame_stats(VP9_COMP *cpi) {
+  RATE_CONTROL *const rc = &cpi->rc;
+
+  // Update the Golden frame usage counts.
+  if (cpi->refresh_golden_frame) {
+    // this frame refreshes means next frames don't unless specified by user
+    rc->frames_since_golden = 0;
+
+    if (cpi->oxcf.pass == 2) {
+      if (!rc->source_alt_ref_pending &&
+          cpi->twopass.gf_group.rf_level[0] == GF_ARF_STD)
+      rc->source_alt_ref_active = 0;
+    } else if (!rc->source_alt_ref_pending) {
+      rc->source_alt_ref_active = 0;
+    }
+
+    // Decrement count down till next gf
+    if (rc->frames_till_gf_update_due > 0)
+      rc->frames_till_gf_update_due--;
+
+  } else if (!cpi->refresh_alt_ref_frame) {
+    // Decrement count down till next gf
+    if (rc->frames_till_gf_update_due > 0)
+      rc->frames_till_gf_update_due--;
+
+    rc->frames_since_golden++;
+  }
+}
+
+void vp9_rc_postencode_update(VP9_COMP *cpi, uint64_t bytes_used) {
+  const VP9_COMMON *const cm = &cpi->common;
+  const VP9EncoderConfig *const oxcf = &cpi->oxcf;
+  RATE_CONTROL *const rc = &cpi->rc;
+  const int qindex = cm->base_qindex;
+
+  if (cpi->oxcf.aq_mode == CYCLIC_REFRESH_AQ && cm->seg.enabled) {
+    vp9_cyclic_refresh_postencode(cpi);
+  }
+
+  // Update rate control heuristics
+  rc->projected_frame_size = (int)(bytes_used << 3);
+
+  // Post encode loop adjustment of Q prediction.
+  vp9_rc_update_rate_correction_factors(cpi);
+
+  // Keep a record of last Q and ambient average Q.
+  if (cm->frame_type == KEY_FRAME) {
+    rc->last_q[KEY_FRAME] = qindex;
+    rc->avg_frame_qindex[KEY_FRAME] =
+        ROUND_POWER_OF_TWO(3 * rc->avg_frame_qindex[KEY_FRAME] + qindex, 2);
+  } else {
+    if (rc->is_src_frame_alt_ref ||
+        !(cpi->refresh_golden_frame || cpi->refresh_alt_ref_frame) ||
+        (cpi->use_svc && oxcf->rc_mode == VPX_CBR)) {
+      rc->last_q[INTER_FRAME] = qindex;
+      rc->avg_frame_qindex[INTER_FRAME] =
+        ROUND_POWER_OF_TWO(3 * rc->avg_frame_qindex[INTER_FRAME] + qindex, 2);
+      rc->ni_frames++;
+      rc->tot_q += vp9_convert_qindex_to_q(qindex, cm->bit_depth);
+      rc->avg_q = rc->tot_q / rc->ni_frames;
+      // Calculate the average Q for normal inter frames (not key or GFU
+      // frames).
+      rc->ni_tot_qi += qindex;
+      rc->ni_av_qi = rc->ni_tot_qi / rc->ni_frames;
+    }
+  }
+
+  // Keep record of last boosted (KF/KF/ARF) Q value.
+  // If the current frame is coded at a lower Q then we also update it.
+  // If all mbs in this group are skipped only update if the Q value is
+  // better than that already stored.
+  // This is used to help set quality in forced key frames to reduce popping
+  if ((qindex < rc->last_boosted_qindex) ||
+      (cm->frame_type == KEY_FRAME) ||
+      (!rc->constrained_gf_group &&
+       (cpi->refresh_alt_ref_frame ||
+        (cpi->refresh_golden_frame && !rc->is_src_frame_alt_ref)))) {
+    rc->last_boosted_qindex = qindex;
+  }
+  if (cm->frame_type == KEY_FRAME)
+    rc->last_kf_qindex = qindex;
+
+  update_buffer_level(cpi, rc->projected_frame_size);
+
+  // Rolling monitors of whether we are over or underspending used to help
+  // regulate min and Max Q in two pass.
+  if (cm->frame_type != KEY_FRAME) {
+    rc->rolling_target_bits = ROUND_POWER_OF_TWO(
+        rc->rolling_target_bits * 3 + rc->this_frame_target, 2);
+    rc->rolling_actual_bits = ROUND_POWER_OF_TWO(
+        rc->rolling_actual_bits * 3 + rc->projected_frame_size, 2);
+    rc->long_rolling_target_bits = ROUND_POWER_OF_TWO(
+        rc->long_rolling_target_bits * 31 + rc->this_frame_target, 5);
+    rc->long_rolling_actual_bits = ROUND_POWER_OF_TWO(
+        rc->long_rolling_actual_bits * 31 + rc->projected_frame_size, 5);
+  }
+
+  // Actual bits spent
+  rc->total_actual_bits += rc->projected_frame_size;
+  rc->total_target_bits += cm->show_frame ? rc->avg_frame_bandwidth : 0;
+
+  rc->total_target_vs_actual = rc->total_actual_bits - rc->total_target_bits;
+
+  if (is_altref_enabled(cpi) && cpi->refresh_alt_ref_frame &&
+      (cm->frame_type != KEY_FRAME))
+    // Update the alternate reference frame stats as appropriate.
+    update_alt_ref_frame_stats(cpi);
+  else
+    // Update the Golden frame stats as appropriate.
+    update_golden_frame_stats(cpi);
+
+  if (cm->frame_type == KEY_FRAME)
+    rc->frames_since_key = 0;
+  if (cm->show_frame) {
+    rc->frames_since_key++;
+    rc->frames_to_key--;
+  }
+
+  // Trigger the resizing of the next frame if it is scaled.
+  cpi->resize_pending =
+      rc->next_frame_size_selector != rc->frame_size_selector;
+  rc->frame_size_selector = rc->next_frame_size_selector;
+}
+
+void vp9_rc_postencode_update_drop_frame(VP9_COMP *cpi) {
+  // Update buffer level with zero size, update frame counters, and return.
+  update_buffer_level(cpi, 0);
+  cpi->rc.frames_since_key++;
+  cpi->rc.frames_to_key--;
+  cpi->rc.rc_2_frame = 0;
+  cpi->rc.rc_1_frame = 0;
+}
+
+// Use this macro to turn on/off use of alt-refs in one-pass mode.
+#define USE_ALTREF_FOR_ONE_PASS   1
+
+static int calc_pframe_target_size_one_pass_vbr(const VP9_COMP *const cpi) {
+  static const int af_ratio = 10;
+  const RATE_CONTROL *const rc = &cpi->rc;
+  int target;
+#if USE_ALTREF_FOR_ONE_PASS
+  target = (!rc->is_src_frame_alt_ref &&
+            (cpi->refresh_golden_frame || cpi->refresh_alt_ref_frame)) ?
+      (rc->avg_frame_bandwidth * rc->baseline_gf_interval * af_ratio) /
+      (rc->baseline_gf_interval + af_ratio - 1) :
+      (rc->avg_frame_bandwidth * rc->baseline_gf_interval) /
+      (rc->baseline_gf_interval + af_ratio - 1);
+#else
+  target = rc->avg_frame_bandwidth;
+#endif
+  return vp9_rc_clamp_pframe_target_size(cpi, target);
+}
+
+static int calc_iframe_target_size_one_pass_vbr(const VP9_COMP *const cpi) {
+  static const int kf_ratio = 25;
+  const RATE_CONTROL *rc = &cpi->rc;
+  const int target = rc->avg_frame_bandwidth * kf_ratio;
+  return vp9_rc_clamp_iframe_target_size(cpi, target);
+}
+
+void vp9_rc_get_one_pass_vbr_params(VP9_COMP *cpi) {
+  VP9_COMMON *const cm = &cpi->common;
+  RATE_CONTROL *const rc = &cpi->rc;
+  int target;
+  // TODO(yaowu): replace the "auto_key && 0" below with proper decision logic.
+  if (!cpi->refresh_alt_ref_frame &&
+      (cm->current_video_frame == 0 ||
+       (cpi->frame_flags & FRAMEFLAGS_KEY) ||
+       rc->frames_to_key == 0 ||
+       (cpi->oxcf.auto_key && 0))) {
+    cm->frame_type = KEY_FRAME;
+    rc->this_key_frame_forced = cm->current_video_frame != 0 &&
+                                rc->frames_to_key == 0;
+    rc->frames_to_key = cpi->oxcf.key_freq;
+    rc->kf_boost = DEFAULT_KF_BOOST;
+    rc->source_alt_ref_active = 0;
+  } else {
+    cm->frame_type = INTER_FRAME;
+  }
+  if (rc->frames_till_gf_update_due == 0) {
+    rc->baseline_gf_interval = DEFAULT_GF_INTERVAL;
+    rc->frames_till_gf_update_due = rc->baseline_gf_interval;
+    // NOTE: frames_till_gf_update_due must be <= frames_to_key.
+    if (rc->frames_till_gf_update_due > rc->frames_to_key) {
+      rc->frames_till_gf_update_due = rc->frames_to_key;
+      rc->constrained_gf_group = 1;
+    } else {
+      rc->constrained_gf_group = 0;
+    }
+    cpi->refresh_golden_frame = 1;
+    rc->source_alt_ref_pending = USE_ALTREF_FOR_ONE_PASS;
+    rc->gfu_boost = DEFAULT_GF_BOOST;
+  }
+  if (cm->frame_type == KEY_FRAME)
+    target = calc_iframe_target_size_one_pass_vbr(cpi);
+  else
+    target = calc_pframe_target_size_one_pass_vbr(cpi);
+  vp9_rc_set_frame_target(cpi, target);
+}
+
+static int calc_pframe_target_size_one_pass_cbr(const VP9_COMP *cpi) {
+  const VP9EncoderConfig *oxcf = &cpi->oxcf;
+  const RATE_CONTROL *rc = &cpi->rc;
+  const SVC *const svc = &cpi->svc;
+  const int64_t diff = rc->optimal_buffer_level - rc->buffer_level;
+  const int64_t one_pct_bits = 1 + rc->optimal_buffer_level / 100;
+  int min_frame_target = MAX(rc->avg_frame_bandwidth >> 4, FRAME_OVERHEAD_BITS);
+  int target;
+
+  if (oxcf->gf_cbr_boost_pct) {
+    const int af_ratio_pct = oxcf->gf_cbr_boost_pct + 100;
+    target =  cpi->refresh_golden_frame ?
+      (rc->avg_frame_bandwidth * rc->baseline_gf_interval * af_ratio_pct) /
+      (rc->baseline_gf_interval * 100 + af_ratio_pct - 100) :
+      (rc->avg_frame_bandwidth * rc->baseline_gf_interval * 100) /
+      (rc->baseline_gf_interval * 100 + af_ratio_pct - 100);
+  } else {
+    target = rc->avg_frame_bandwidth;
+  }
+  if (svc->number_temporal_layers > 1 &&
+      oxcf->rc_mode == VPX_CBR) {
+    // Note that for layers, avg_frame_bandwidth is the cumulative
+    // per-frame-bandwidth. For the target size of this frame, use the
+    // layer average frame size (i.e., non-cumulative per-frame-bw).
+    int current_temporal_layer = svc->temporal_layer_id;
+    const LAYER_CONTEXT *lc = &svc->layer_context[current_temporal_layer];
+    target = lc->avg_frame_size;
+    min_frame_target = MAX(lc->avg_frame_size >> 4, FRAME_OVERHEAD_BITS);
+  }
+  if (diff > 0) {
+    // Lower the target bandwidth for this frame.
+    const int pct_low = (int)MIN(diff / one_pct_bits, oxcf->under_shoot_pct);
+    target -= (target * pct_low) / 200;
+  } else if (diff < 0) {
+    // Increase the target bandwidth for this frame.
+    const int pct_high = (int)MIN(-diff / one_pct_bits, oxcf->over_shoot_pct);
+    target += (target * pct_high) / 200;
+  }
+  if (oxcf->rc_max_inter_bitrate_pct) {
+    const int max_rate = rc->avg_frame_bandwidth *
+                         oxcf->rc_max_inter_bitrate_pct / 100;
+    target = MIN(target, max_rate);
+  }
+  return MAX(min_frame_target, target);
+}
+
+static int calc_iframe_target_size_one_pass_cbr(const VP9_COMP *cpi) {
+  const RATE_CONTROL *rc = &cpi->rc;
+  const VP9EncoderConfig *oxcf = &cpi->oxcf;
+  const SVC *const svc = &cpi->svc;
+  int target;
+  if (cpi->common.current_video_frame == 0) {
+    target = ((rc->starting_buffer_level / 2) > INT_MAX)
+      ? INT_MAX : (int)(rc->starting_buffer_level / 2);
+  } else {
+    int kf_boost = 32;
+    double framerate = cpi->framerate;
+    if (svc->number_temporal_layers > 1 &&
+        oxcf->rc_mode == VPX_CBR) {
+      // Use the layer framerate for temporal layers CBR mode.
+      const LAYER_CONTEXT *lc = &svc->layer_context[svc->temporal_layer_id];
+      framerate = lc->framerate;
+    }
+    kf_boost = MAX(kf_boost, (int)(2 * framerate - 16));
+    if (rc->frames_since_key <  framerate / 2) {
+      kf_boost = (int)(kf_boost * rc->frames_since_key /
+                       (framerate / 2));
+    }
+    target = ((16 + kf_boost) * rc->avg_frame_bandwidth) >> 4;
+  }
+  return vp9_rc_clamp_iframe_target_size(cpi, target);
+}
+
+void vp9_rc_get_svc_params(VP9_COMP *cpi) {
+  VP9_COMMON *const cm = &cpi->common;
+  RATE_CONTROL *const rc = &cpi->rc;
+  int target = rc->avg_frame_bandwidth;
+  if ((cm->current_video_frame == 0) ||
+      (cpi->frame_flags & FRAMEFLAGS_KEY) ||
+      (cpi->oxcf.auto_key && (rc->frames_since_key %
+          cpi->oxcf.key_freq == 0))) {
+    cm->frame_type = KEY_FRAME;
+    rc->source_alt_ref_active = 0;
+
+    if (is_two_pass_svc(cpi)) {
+      cpi->svc.layer_context[cpi->svc.spatial_layer_id].is_key_frame = 1;
+      cpi->ref_frame_flags &=
+          (~VP9_LAST_FLAG & ~VP9_GOLD_FLAG & ~VP9_ALT_FLAG);
+    }
+
+    if (cpi->oxcf.pass == 0 && cpi->oxcf.rc_mode == VPX_CBR) {
+      target = calc_iframe_target_size_one_pass_cbr(cpi);
+    }
+  } else {
+    cm->frame_type = INTER_FRAME;
+
+    if (is_two_pass_svc(cpi)) {
+      LAYER_CONTEXT *lc = &cpi->svc.layer_context[cpi->svc.spatial_layer_id];
+      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;
+        if (lc->is_key_frame)
+          cpi->ref_frame_flags &= (~VP9_LAST_FLAG);
+      }
+      cpi->ref_frame_flags &= (~VP9_ALT_FLAG);
+    }
+
+    if (cpi->oxcf.pass == 0 && cpi->oxcf.rc_mode == VPX_CBR) {
+      target = calc_pframe_target_size_one_pass_cbr(cpi);
+    }
+  }
+
+  // Any update/change of global cyclic refresh parameters (amount/delta-qp)
+  // should be done here, before the frame qp is selected.
+  if (cpi->oxcf.aq_mode == CYCLIC_REFRESH_AQ)
+    vp9_cyclic_refresh_update_parameters(cpi);
+
+  vp9_rc_set_frame_target(cpi, target);
+  rc->frames_till_gf_update_due = INT_MAX;
+  rc->baseline_gf_interval = INT_MAX;
+}
+
+void vp9_rc_get_one_pass_cbr_params(VP9_COMP *cpi) {
+  VP9_COMMON *const cm = &cpi->common;
+  RATE_CONTROL *const rc = &cpi->rc;
+  int target;
+  // TODO(yaowu): replace the "auto_key && 0" below with proper decision logic.
+  if ((cm->current_video_frame == 0 ||
+      (cpi->frame_flags & FRAMEFLAGS_KEY) ||
+      rc->frames_to_key == 0 ||
+      (cpi->oxcf.auto_key && 0))) {
+    cm->frame_type = KEY_FRAME;
+    rc->this_key_frame_forced = cm->current_video_frame != 0 &&
+                                rc->frames_to_key == 0;
+    rc->frames_to_key = cpi->oxcf.key_freq;
+    rc->kf_boost = DEFAULT_KF_BOOST;
+    rc->source_alt_ref_active = 0;
+  } else {
+    cm->frame_type = INTER_FRAME;
+  }
+  if (rc->frames_till_gf_update_due == 0) {
+    if (cpi->oxcf.aq_mode == CYCLIC_REFRESH_AQ)
+      vp9_cyclic_refresh_set_golden_update(cpi);
+    else
+      rc->baseline_gf_interval = DEFAULT_GF_INTERVAL;
+    rc->frames_till_gf_update_due = rc->baseline_gf_interval;
+    // NOTE: frames_till_gf_update_due must be <= frames_to_key.
+    if (rc->frames_till_gf_update_due > rc->frames_to_key)
+      rc->frames_till_gf_update_due = rc->frames_to_key;
+    cpi->refresh_golden_frame = 1;
+    rc->gfu_boost = DEFAULT_GF_BOOST;
+  }
+
+  // Any update/change of global cyclic refresh parameters (amount/delta-qp)
+  // should be done here, before the frame qp is selected.
+  if (cpi->oxcf.aq_mode == CYCLIC_REFRESH_AQ)
+    vp9_cyclic_refresh_update_parameters(cpi);
+
+  if (cm->frame_type == KEY_FRAME)
+    target = calc_iframe_target_size_one_pass_cbr(cpi);
+  else
+    target = calc_pframe_target_size_one_pass_cbr(cpi);
+
+  vp9_rc_set_frame_target(cpi, target);
+}
+
+int vp9_compute_qdelta(const RATE_CONTROL *rc, double qstart, double qtarget,
+                       vpx_bit_depth_t bit_depth) {
+  int start_index = rc->worst_quality;
+  int target_index = rc->worst_quality;
+  int i;
+
+  // Convert the average q value to an index.
+  for (i = rc->best_quality; i < rc->worst_quality; ++i) {
+    start_index = i;
+    if (vp9_convert_qindex_to_q(i, bit_depth) >= qstart)
+      break;
+  }
+
+  // Convert the q target to an index
+  for (i = rc->best_quality; i < rc->worst_quality; ++i) {
+    target_index = i;
+    if (vp9_convert_qindex_to_q(i, bit_depth) >= qtarget)
+      break;
+  }
+
+  return target_index - start_index;
+}
+
+int vp9_compute_qdelta_by_rate(const RATE_CONTROL *rc, FRAME_TYPE frame_type,
+                               int qindex, double rate_target_ratio,
+                               vpx_bit_depth_t bit_depth) {
+  int target_index = rc->worst_quality;
+  int i;
+
+  // Look up the current projected bits per block for the base index
+  const int base_bits_per_mb = vp9_rc_bits_per_mb(frame_type, qindex, 1.0,
+                                                  bit_depth);
+
+  // Find the target bits per mb based on the base value and given ratio.
+  const int target_bits_per_mb = (int)(rate_target_ratio * base_bits_per_mb);
+
+  // Convert the q target to an index
+  for (i = rc->best_quality; i < rc->worst_quality; ++i) {
+    if (vp9_rc_bits_per_mb(frame_type, i, 1.0, bit_depth) <=
+        target_bits_per_mb) {
+      target_index = i;
+      break;
+    }
+  }
+  return target_index - qindex;
+}
+
+#define MIN_GF_INTERVAL     4
+#define MAX_GF_INTERVAL     16
+void vp9_rc_set_gf_interval_range(const VP9_COMP *const cpi,
+                                  RATE_CONTROL *const rc) {
+  const VP9EncoderConfig *const oxcf = &cpi->oxcf;
+
+  // Set a minimum interval.
+  rc->min_gf_interval =
+    MIN(MAX_GF_INTERVAL, MAX(MIN_GF_INTERVAL, (int)(cpi->framerate * 0.125)));
+
+  // Set Maximum gf/arf interval.
+  rc->max_gf_interval =
+    MIN(MAX_GF_INTERVAL, (int)(cpi->framerate * 0.75));
+  // Round up to next even number if odd.
+  rc->max_gf_interval += (rc->max_gf_interval & 0x01);
+
+  // Extended interval for genuinely static scenes
+  rc->static_scene_max_gf_interval = MAX_LAG_BUFFERS * 2;
+
+  if (is_altref_enabled(cpi)) {
+    if (rc->static_scene_max_gf_interval > oxcf->lag_in_frames - 1)
+      rc->static_scene_max_gf_interval = oxcf->lag_in_frames - 1;
+  }
+
+  if (rc->max_gf_interval > rc->static_scene_max_gf_interval)
+    rc->max_gf_interval = rc->static_scene_max_gf_interval;
+
+  // Clamp min to max
+  rc->min_gf_interval = MIN(rc->min_gf_interval, rc->max_gf_interval);
+}
+
+void vp9_rc_update_framerate(VP9_COMP *cpi) {
+  const VP9_COMMON *const cm = &cpi->common;
+  const VP9EncoderConfig *const oxcf = &cpi->oxcf;
+  RATE_CONTROL *const rc = &cpi->rc;
+  int vbr_max_bits;
+
+  rc->avg_frame_bandwidth = (int)(oxcf->target_bandwidth / cpi->framerate);
+  rc->min_frame_bandwidth = (int)(rc->avg_frame_bandwidth *
+                                oxcf->two_pass_vbrmin_section / 100);
+
+  rc->min_frame_bandwidth = MAX(rc->min_frame_bandwidth, FRAME_OVERHEAD_BITS);
+
+  // A maximum bitrate for a frame is defined.
+  // The baseline for this aligns with HW implementations that
+  // can support decode of 1080P content up to a bitrate of MAX_MB_RATE bits
+  // per 16x16 MB (averaged over a frame). However this limit is extended if
+  // a very high rate is given on the command line or the the rate cannnot
+  // be acheived because of a user specificed max q (e.g. when the user
+  // specifies lossless encode.
+  vbr_max_bits = (int)(((int64_t)rc->avg_frame_bandwidth *
+                     oxcf->two_pass_vbrmax_section) / 100);
+  rc->max_frame_bandwidth = MAX(MAX((cm->MBs * MAX_MB_RATE), MAXRATE_1080P),
+                                    vbr_max_bits);
+
+  vp9_rc_set_gf_interval_range(cpi, rc);
+}
+
+#define VBR_PCT_ADJUSTMENT_LIMIT 50
+// For VBR...adjustment to the frame target based on error from previous frames
+static void vbr_rate_correction(VP9_COMP *cpi,
+                                int *this_frame_target,
+                                int64_t vbr_bits_off_target) {
+  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;
+  }
+}
+
+void vp9_set_target_rate(VP9_COMP *cpi) {
+  RATE_CONTROL *const rc = &cpi->rc;
+  int target_rate = rc->base_frame_target;
+
+  // Correction to rate target based on prior over or under shoot.
+  if (cpi->oxcf.rc_mode == VPX_VBR || cpi->oxcf.rc_mode == VPX_CQ)
+    vbr_rate_correction(cpi, &target_rate, rc->vbr_bits_off_target);
+  vp9_rc_set_frame_target(cpi, target_rate);
+}