From 40e63d4b5107246e198b255d0ea46f4a15030bbf Mon Sep 17 00:00:00 2001
From: Deb Mukherjee <debargha@google.com>
Date: Tue, 4 Feb 2014 11:42:50 -0800
Subject: [PATCH] One-pass rate control cleanups/fixes/refactoring

Inlcudes a number cleanups:
1. Moves the one-pass pre-encode parameter setting functions
to vp9_ratectrl.c
2. Deprecates per_frame_bandwidth in RATE_CONTROL structure
3. Removes target_bandwidth in cpi structure since it is not used.
4. Various renaming of functions

There is no bit-stream change in 2-pass, one-pass cbr and one-pass
vbr modes.

Change-Id: Ifd9916bf4d485b7d04c5f52044ffe6703254ccbd
---
 vp9/encoder/vp9_firstpass.c | 227 ++++----------------------
 vp9/encoder/vp9_firstpass.h |  11 +-
 vp9/encoder/vp9_onyx_if.c   |  26 +--
 vp9/encoder/vp9_onyx_int.h  |   3 +-
 vp9/encoder/vp9_ratectrl.c  | 316 ++++++++++++++++++++++++++----------
 vp9/encoder/vp9_ratectrl.h  |  76 ++++++---
 6 files changed, 326 insertions(+), 333 deletions(-)

diff --git a/vp9/encoder/vp9_firstpass.c b/vp9/encoder/vp9_firstpass.c
index a343c7680..dcebefb10 100644
--- a/vp9/encoder/vp9_firstpass.c
+++ b/vp9/encoder/vp9_firstpass.c
@@ -49,8 +49,9 @@
 
 #define DOUBLE_DIVIDE_CHECK(x) ((x) < 0 ? (x) - 0.000001 : (x) + 0.000001)
 
-#define MIN_BOOST        300
-#define KEY_FRAME_BOOST 2000
+#define MIN_KF_BOOST        300
+
+#define DISABLE_RC_LONG_TERM_MEM 0
 
 static void swap_yv12(YV12_BUFFER_CONFIG *a, YV12_BUFFER_CONFIG *b) {
   YV12_BUFFER_CONFIG temp = *a;
@@ -1725,7 +1726,7 @@ static void define_gf_group(VP9_COMP *cpi, FIRSTPASS_STATS *this_frame) {
         (!rc->source_alt_ref_pending &&
          (cpi->common.frame_type != KEY_FRAME))) {
       // Per frame bit target for this frame
-      rc->per_frame_bandwidth = gf_bits;
+      vp9_rc_set_frame_target(cpi, gf_bits);
     }
   }
 
@@ -1827,12 +1828,7 @@ static void assign_std_frame_bits(VP9_COMP *cpi, FIRSTPASS_STATS *this_frame) {
     cpi->twopass.gf_group_bits = 0;
 
   // Per frame bit target for this frame.
-  cpi->rc.per_frame_bandwidth = target_frame_size;
-}
-
-static int test_for_kf_one_pass(VP9_COMP *cpi) {
-  // Placeholder function for auto key frame
-  return 0;
+  vp9_rc_set_frame_target(cpi, target_frame_size);
 }
 
 static int test_candidate_kf(VP9_COMP *cpi,
@@ -2170,8 +2166,8 @@ static void find_next_key_frame(VP9_COMP *cpi, FIRSTPASS_STATS *this_frame) {
     if (kf_boost < (rc->frames_to_key * 3))
       kf_boost = (rc->frames_to_key * 3);
 
-    if (kf_boost < MIN_BOOST)
-      kf_boost = MIN_BOOST;
+    if (kf_boost < MIN_KF_BOOST)
+      kf_boost = MIN_KF_BOOST;
 
     // Make a note of baseline boost and the zero motion
     // accumulator value for use elsewhere.
@@ -2235,13 +2231,9 @@ static void find_next_key_frame(VP9_COMP *cpi, FIRSTPASS_STATS *this_frame) {
         twopass->kf_bits = alt_kf_bits;
       }
     }
-
     twopass->kf_group_bits -= twopass->kf_bits;
-
-    // Peer frame bit target for this frame
-    rc->per_frame_bandwidth = twopass->kf_bits;
-    // Convert to a per second bitrate
-    cpi->target_bandwidth = (int)(twopass->kf_bits * cpi->output_framerate);
+    // Per frame bit target for this frame.
+    vp9_rc_set_frame_target(cpi, twopass->kf_bits);
   }
 
   // Note the total error score of the kf group minus the key frame itself
@@ -2253,176 +2245,7 @@ static void find_next_key_frame(VP9_COMP *cpi, FIRSTPASS_STATS *this_frame) {
   twopass->modified_error_left -= kf_group_err;
 }
 
-void vp9_get_svc_params(VP9_COMP *cpi) {
-  VP9_COMMON *const cm = &cpi->common;
-  if ((cm->current_video_frame == 0) ||
-      (cm->frame_flags & FRAMEFLAGS_KEY) ||
-      (cpi->oxcf.auto_key && (cpi->rc.frames_since_key %
-                              cpi->key_frame_frequency == 0))) {
-    cm->frame_type = KEY_FRAME;
-    cpi->rc.source_alt_ref_active = 0;
-  } else {
-    cm->frame_type = INTER_FRAME;
-  }
-  cpi->rc.frames_till_gf_update_due = INT_MAX;
-  cpi->rc.baseline_gf_interval = INT_MAX;
-}
-
-// Use this macro to turn on/off use of alt-refs in one-pass mode.
-#define USE_ALTREF_FOR_ONE_PASS   1
-
-void vp9_get_one_pass_params(VP9_COMP *cpi) {
-  VP9_COMMON *const cm = &cpi->common;
-  if (!cpi->refresh_alt_ref_frame &&
-      (cm->current_video_frame == 0 ||
-       cm->frame_flags & FRAMEFLAGS_KEY ||
-       cpi->rc.frames_to_key == 0 ||
-       (cpi->oxcf.auto_key && test_for_kf_one_pass(cpi)))) {
-    cm->frame_type = KEY_FRAME;
-    cpi->rc.this_key_frame_forced = cm->current_video_frame != 0 &&
-                                    cpi->rc.frames_to_key == 0;
-    cpi->rc.frames_to_key = cpi->key_frame_frequency;
-    cpi->rc.kf_boost = KEY_FRAME_BOOST;
-    cpi->rc.source_alt_ref_active = 0;
-    cpi->rc.per_frame_bandwidth = cpi->rc.av_per_frame_bandwidth * 8;
-    if (cm->current_video_frame == 0) {
-      cpi->rc.active_worst_quality = cpi->rc.worst_quality;
-    } else {
-      // Choose active worst quality twice as large as the last q.
-      cpi->rc.active_worst_quality = cpi->rc.last_q[KEY_FRAME] * 2;
-      if (cpi->rc.active_worst_quality > cpi->rc.worst_quality)
-        cpi->rc.active_worst_quality = cpi->rc.worst_quality;
-    }
-  } else {
-    cm->frame_type = INTER_FRAME;
-    cpi->rc.per_frame_bandwidth = cpi->rc.av_per_frame_bandwidth;
-    if (cm->current_video_frame == 1) {
-      cpi->rc.active_worst_quality = cpi->rc.worst_quality;
-    } else {
-      // Choose active worst quality twice as large as the last q.
-      cpi->rc.active_worst_quality = cpi->rc.last_q[INTER_FRAME] * 2;
-      if (cpi->rc.active_worst_quality > cpi->rc.worst_quality)
-        cpi->rc.active_worst_quality = cpi->rc.worst_quality;
-    }
-  }
-  if (cpi->rc.frames_till_gf_update_due == 0) {
-    cpi->rc.baseline_gf_interval = DEFAULT_GF_INTERVAL;
-    cpi->rc.frames_till_gf_update_due = cpi->rc.baseline_gf_interval;
-    // NOTE: frames_till_gf_update_due must be <= frames_to_key.
-    if (cpi->rc.frames_till_gf_update_due > cpi->rc.frames_to_key)
-      cpi->rc.frames_till_gf_update_due = cpi->rc.frames_to_key;
-    cpi->refresh_golden_frame = 1;
-    cpi->rc.source_alt_ref_pending = USE_ALTREF_FOR_ONE_PASS;
-    cpi->rc.gfu_boost = 2000;
-  }
-}
-
-// Adjust active_worst_quality level based on buffer level.
-static int calc_active_worst_quality_from_buffer_level(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_CONFIG *oxcf = &cpi->oxcf;
-  const RATE_CONTROL *rc = &cpi->rc;
-  int active_worst_quality = rc->active_worst_quality;
-  // Maximum limit for down adjustment, ~20%.
-  int max_adjustment_down = active_worst_quality / 5;
-  // Buffer level below which we push active_worst to worst_quality.
-  int critical_level = oxcf->optimal_buffer_level >> 2;
-  int adjustment = 0;
-  int buff_lvl_step = 0;
-  if (rc->buffer_level > oxcf->optimal_buffer_level) {
-    // Adjust down.
-    if (max_adjustment_down) {
-      buff_lvl_step = (int)((oxcf->maximum_buffer_size -
-          oxcf->optimal_buffer_level) / max_adjustment_down);
-      if (buff_lvl_step)
-        adjustment = (int)((rc->buffer_level - oxcf->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 = (oxcf->optimal_buffer_level - critical_level);
-      if (buff_lvl_step) {
-        adjustment = (rc->worst_quality - rc->avg_frame_qindex[INTER_FRAME]) *
-                         (oxcf->optimal_buffer_level - rc->buffer_level) /
-                             buff_lvl_step;
-      }
-      active_worst_quality = rc->avg_frame_qindex[INTER_FRAME] + adjustment;
-    }
-  } else {
-    // Set to worst_quality if buffer is below critical level.
-    active_worst_quality = rc->worst_quality;
-  }
-  return active_worst_quality;
-}
-
-static int calc_pframe_target_size_one_pass_cbr(const VP9_COMP *cpi) {
-  const VP9_CONFIG *oxcf = &cpi->oxcf;
-  const RATE_CONTROL *rc = &cpi->rc;
-  int target = rc->av_per_frame_bandwidth;
-  const int64_t diff = oxcf->optimal_buffer_level - rc->buffer_level;
-  const int one_pct_bits = 1 + oxcf->optimal_buffer_level / 100;
-  if (diff > 0) {
-    // Lower the target bandwidth for this frame.
-    const int pct_low = 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 = MIN(-diff / one_pct_bits, oxcf->over_shoot_pct);
-    target += (target * pct_high) / 200;
-  }
-  return target;
-}
-
-static int calc_iframe_target_size_one_pass_cbr(const VP9_COMP *cpi) {
-  int per_frame_bandwidth;
-  const RATE_CONTROL *rc = &cpi->rc;
-  if (cpi->common.current_video_frame == 0) {
-    per_frame_bandwidth = cpi->oxcf.starting_buffer_level / 2;
-  } else {
-    int initial_boost = 32;
-    int kf_boost = MAX(initial_boost, (int)(2 * cpi->output_framerate - 16));
-    if (rc->frames_since_key < cpi->output_framerate / 2) {
-      kf_boost = (int)(kf_boost * rc->frames_since_key /
-                       (cpi->output_framerate / 2));
-    }
-    per_frame_bandwidth =
-        ((16 + kf_boost) * rc->av_per_frame_bandwidth) >> 4;
-  }
-  return per_frame_bandwidth;
-}
-
-void vp9_get_one_pass_cbr_params(VP9_COMP *cpi) {
-  VP9_COMMON *const cm = &cpi->common;
-  if ((cm->current_video_frame == 0 ||
-      cm->frame_flags & FRAMEFLAGS_KEY ||
-      cpi->rc.frames_to_key == 0 ||
-      (cpi->oxcf.auto_key && test_for_kf_one_pass(cpi)))) {
-    cm->frame_type = KEY_FRAME;
-    cpi->rc.this_key_frame_forced = cm->current_video_frame != 0 &&
-                                    cpi->rc.frames_to_key == 0;
-    cpi->rc.frames_to_key = cpi->key_frame_frequency;
-    cpi->rc.kf_boost = KEY_FRAME_BOOST;
-    cpi->rc.source_alt_ref_active = 0;
-    cpi->rc.per_frame_bandwidth = calc_iframe_target_size_one_pass_cbr(cpi);
-    cpi->rc.active_worst_quality = cpi->rc.worst_quality;
-  } else {
-    cm->frame_type = INTER_FRAME;
-    cpi->rc.per_frame_bandwidth = calc_pframe_target_size_one_pass_cbr(cpi);
-    cpi->rc.active_worst_quality =
-        calc_active_worst_quality_from_buffer_level(cpi);
-  }
-  // Don't use gf_update by default in CBR mode.
-  cpi->rc.frames_till_gf_update_due = INT_MAX;
-  cpi->rc.baseline_gf_interval = INT_MAX;
-}
-
-void vp9_get_first_pass_params(VP9_COMP *cpi) {
+void vp9_rc_get_first_pass_params(VP9_COMP *cpi) {
   VP9_COMMON *const cm = &cpi->common;
   if (!cpi->refresh_alt_ref_frame &&
       (cm->current_video_frame == 0 ||
@@ -2435,7 +2258,7 @@ void vp9_get_first_pass_params(VP9_COMP *cpi) {
   cpi->rc.frames_to_key = INT_MAX;
 }
 
-void vp9_get_second_pass_params(VP9_COMP *cpi) {
+void vp9_rc_get_second_pass_params(VP9_COMP *cpi) {
   VP9_COMMON *const cm = &cpi->common;
   RATE_CONTROL *const rc = &cpi->rc;
   struct twopass_rc *const twopass = &cpi->twopass;
@@ -2446,13 +2269,14 @@ void vp9_get_second_pass_params(VP9_COMP *cpi) {
 
   double this_frame_intra_error;
   double this_frame_coded_error;
+  int target;
 
   if (!twopass->stats_in)
     return;
 
   if (cpi->refresh_alt_ref_frame) {
     cm->frame_type = INTER_FRAME;
-    rc->per_frame_bandwidth = twopass->gf_bits;
+    vp9_rc_set_frame_target(cpi, twopass->gf_bits);
     return;
   }
 
@@ -2463,7 +2287,7 @@ void vp9_get_second_pass_params(VP9_COMP *cpi) {
   } else if (cm->current_video_frame == 0) {
     // Special case code for first frame.
     const int section_target_bandwidth = (int)(twopass->bits_left /
-                                             frames_left);
+                                               frames_left);
     const int tmp_q = estimate_max_q(cpi, &twopass->total_left_stats,
                                      section_target_bandwidth);
 
@@ -2539,11 +2363,11 @@ void vp9_get_second_pass_params(VP9_COMP *cpi) {
     }
   }
 
-  // Set nominal per second bandwidth for this frame
-  cpi->target_bandwidth = (int)(rc->per_frame_bandwidth *
-                                   cpi->output_framerate);
-  if (cpi->target_bandwidth < 0)
-    cpi->target_bandwidth = 0;
+  if (cpi->common.frame_type == KEY_FRAME)
+    target = vp9_rc_clamp_iframe_target_size(cpi, rc->this_frame_target);
+  else
+    target = vp9_rc_clamp_pframe_target_size(cpi, rc->this_frame_target);
+  vp9_rc_set_frame_target(cpi, target);
 
   // Update the total stats remaining structure
   subtract_stats(&twopass->total_left_stats, &this_frame);
@@ -2554,5 +2378,18 @@ void vp9_twopass_postencode_update(VP9_COMP *cpi, uint64_t bytes_used) {
   cpi->twopass.bits_left -=  cpi->rc.this_frame_target;
 #else
   cpi->twopass.bits_left -= 8 * bytes_used;
+  // Update bits left to the kf and gf groups to account for overshoot or
+  // undershoot on these frames
+  if (cm->frame_type == KEY_FRAME) {
+    cpi->twopass.kf_group_bits += cpi->rc.this_frame_target -
+        cpi->rc.projected_frame_size;
+
+    cpi->twopass.kf_group_bits = MAX(cpi->twopass.kf_group_bits, 0);
+  } else if (cpi->refresh_golden_frame || cpi->refresh_alt_ref_frame) {
+    cpi->twopass.gf_group_bits += cpi->rc.this_frame_target -
+        cpi->rc.projected_frame_size;
+
+    cpi->twopass.gf_group_bits = MAX(cpi->twopass.gf_group_bits, 0);
+  }
 #endif
 }
diff --git a/vp9/encoder/vp9_firstpass.h b/vp9/encoder/vp9_firstpass.h
index ca5b10080..19b59815a 100644
--- a/vp9/encoder/vp9_firstpass.h
+++ b/vp9/encoder/vp9_firstpass.h
@@ -17,18 +17,17 @@ extern "C" {
 #endif
 
 void vp9_init_first_pass(VP9_COMP *cpi);
+void vp9_rc_get_first_pass_params(VP9_COMP *cpi);
 void vp9_first_pass(VP9_COMP *cpi);
 void vp9_end_first_pass(VP9_COMP *cpi);
 
 void vp9_init_second_pass(VP9_COMP *cpi);
-void vp9_get_second_pass_params(VP9_COMP *cpi);
+void vp9_rc_get_second_pass_params(VP9_COMP *cpi);
 void vp9_end_second_pass(VP9_COMP *cpi);
 
-void vp9_get_first_pass_params(VP9_COMP *cpi);
-void vp9_get_one_pass_params(VP9_COMP *cpi);
-void vp9_get_one_pass_cbr_params(VP9_COMP *cpi);
-void vp9_get_svc_params(VP9_COMP *cpi);
-
+// Post encode update of the rate control parameters for 2-pass
+void vp9_twopass_postencode_update(struct VP9_COMP *cpi,
+                                   uint64_t bytes_used);
 #ifdef __cplusplus
 }  // extern "C"
 #endif
diff --git a/vp9/encoder/vp9_onyx_if.c b/vp9/encoder/vp9_onyx_if.c
index 3cf8ddb8c..c60407eef 100644
--- a/vp9/encoder/vp9_onyx_if.c
+++ b/vp9/encoder/vp9_onyx_if.c
@@ -1104,8 +1104,6 @@ void vp9_new_framerate(VP9_COMP *cpi, double framerate) {
 
   cpi->oxcf.framerate = framerate;
   cpi->output_framerate = cpi->oxcf.framerate;
-  cpi->rc.per_frame_bandwidth = (int)(cpi->oxcf.target_bandwidth
-                                      / cpi->output_framerate);
   cpi->rc.av_per_frame_bandwidth = (int)(cpi->oxcf.target_bandwidth
                                          / cpi->output_framerate);
   cpi->rc.min_frame_bandwidth = (int)(cpi->rc.av_per_frame_bandwidth *
@@ -1344,8 +1342,6 @@ void vp9_change_config(VP9_PTR ptr, VP9_CONFIG *oxcf) {
 
   cm->interp_filter = DEFAULT_INTERP_FILTER;
 
-  cpi->target_bandwidth = cpi->oxcf.target_bandwidth;
-
   cm->display_width = cpi->oxcf.width;
   cm->display_height = cpi->oxcf.height;
 
@@ -3025,10 +3021,7 @@ static void encode_frame_to_data_rate(VP9_COMP *cpi,
   if (cpi->pass == 0 &&
       cpi->oxcf.end_usage == USAGE_STREAM_FROM_SERVER &&
       cm->frame_type != KEY_FRAME) {
-    if (vp9_drop_frame(cpi)) {
-      // Update buffer level with zero size, update frame counters, and return.
-      vp9_update_buffer_level(cpi, 0);
-      cm->last_frame_type = cm->frame_type;
+    if (vp9_rc_drop_frame(cpi)) {
       vp9_rc_postencode_update_drop_frame(cpi);
       cm->current_video_frame++;
       return;
@@ -3068,9 +3061,6 @@ static void encode_frame_to_data_rate(VP9_COMP *cpi,
   vp9_write_yuv_frame(cpi->Source);
 #endif
 
-  // Decide how big to make the frame.
-  vp9_rc_pick_frame_size_target(cpi);
-
   // Decide frame size bounds
   vp9_rc_compute_frame_size_bounds(cpi, cpi->rc.this_frame_target,
                                    &frame_under_shoot_limit,
@@ -3171,10 +3161,6 @@ static void encode_frame_to_data_rate(VP9_COMP *cpi,
   vp9_update_mode_context_stats(cpi);
 #endif
 
-  /* Move storing frame_type out of the above loop since it is also
-   * needed in motion search besides loopfilter */
-  cm->last_frame_type = cm->frame_type;
-
 #if 0
   output_frame_level_debug_stats(cpi);
 #endif
@@ -3262,16 +3248,16 @@ static void encode_frame_to_data_rate(VP9_COMP *cpi,
 
 static void SvcEncode(VP9_COMP *cpi, size_t *size, uint8_t *dest,
                       unsigned int *frame_flags) {
-  vp9_get_svc_params(cpi);
+  vp9_rc_get_svc_params(cpi);
   encode_frame_to_data_rate(cpi, size, dest, frame_flags);
 }
 
 static void Pass0Encode(VP9_COMP *cpi, size_t *size, uint8_t *dest,
                         unsigned int *frame_flags) {
   if (cpi->oxcf.end_usage == USAGE_STREAM_FROM_SERVER) {
-    vp9_get_one_pass_cbr_params(cpi);
+    vp9_rc_get_one_pass_cbr_params(cpi);
   } else {
-    vp9_get_one_pass_params(cpi);
+    vp9_rc_get_one_pass_vbr_params(cpi);
   }
   encode_frame_to_data_rate(cpi, size, dest, frame_flags);
 }
@@ -3282,7 +3268,7 @@ static void Pass1Encode(VP9_COMP *cpi, size_t *size, uint8_t *dest,
   (void) dest;
   (void) frame_flags;
 
-  vp9_get_first_pass_params(cpi);
+  vp9_rc_get_first_pass_params(cpi);
   vp9_set_quantizer(cpi, find_fp_qindex());
   vp9_first_pass(cpi);
 }
@@ -3291,7 +3277,7 @@ static void Pass2Encode(VP9_COMP *cpi, size_t *size,
                         uint8_t *dest, unsigned int *frame_flags) {
   cpi->enable_encode_breakout = 1;
 
-  vp9_get_second_pass_params(cpi);
+  vp9_rc_get_second_pass_params(cpi);
   encode_frame_to_data_rate(cpi, size, dest, frame_flags);
 
   vp9_twopass_postencode_update(cpi, *size);
diff --git a/vp9/encoder/vp9_onyx_int.h b/vp9/encoder/vp9_onyx_int.h
index a98c6bf80..ae9401668 100644
--- a/vp9/encoder/vp9_onyx_int.h
+++ b/vp9/encoder/vp9_onyx_int.h
@@ -36,7 +36,6 @@
 extern "C" {
 #endif
 
-#define DISABLE_RC_LONG_TERM_MEM 0
 // #define MODE_TEST_HIT_STATS
 
 // #define SPEEDSTATS 1
@@ -47,6 +46,7 @@ extern "C" {
 #define MIN_GF_INTERVAL             4
 #endif
 #define DEFAULT_GF_INTERVAL         7
+#define DEFAULT_KF_BOOST            2000
 
 #define KEY_FRAME_CONTEXT 5
 
@@ -530,7 +530,6 @@ typedef struct VP9_COMP {
   vp9_coeff_probs_model frame_coef_probs[TX_SIZES][PLANE_TYPES];
   vp9_coeff_stats frame_branch_ct[TX_SIZES][PLANE_TYPES];
 
-  int64_t target_bandwidth;
   struct vpx_codec_pkt_list  *output_pkt_list;
 
   MBGRAPH_FRAME_STATS mbgraph_stats[MAX_LAG_BUFFERS];
diff --git a/vp9/encoder/vp9_ratectrl.c b/vp9/encoder/vp9_ratectrl.c
index f8cfe4929..1172012de 100644
--- a/vp9/encoder/vp9_ratectrl.c
+++ b/vp9/encoder/vp9_ratectrl.c
@@ -209,24 +209,40 @@ static int estimate_bits_at_q(int frame_kind, int q, int mbs,
                            : (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 int min_frame_target = MAX(rc->min_frame_bandwidth,
+                                   rc->av_per_frame_bandwidth >> 5);
+  if (target < min_frame_target)
+    target = min_frame_target;
+  if (cpi->refresh_golden_frame && rc->source_alt_ref_active) {
+    // 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 = 0;
+  }
+  // Clip the frame target to the maximum allowed value.
+  if (target > rc->max_frame_bandwidth)
+    target = rc->max_frame_bandwidth;
+  return target;
+}
 
-static void calc_iframe_target_size(VP9_COMP *cpi) {
+int vp9_rc_clamp_iframe_target_size(const VP9_COMP *const cpi, int target) {
+  const RATE_CONTROL *rc = &cpi->rc;
   const VP9_CONFIG *oxcf = &cpi->oxcf;
-  RATE_CONTROL *const rc = &cpi->rc;
-  int target = rc->per_frame_bandwidth;
-
-  vp9_clear_system_state();  // __asm emms;
-
   if (oxcf->rc_max_intra_bitrate_pct) {
-    const int max_rate = rc->per_frame_bandwidth *
+    const int max_rate = rc->av_per_frame_bandwidth *
         oxcf->rc_max_intra_bitrate_pct / 100;
     target = MIN(target, max_rate);
   }
-  rc->this_frame_target = target;
+  if (target > rc->max_frame_bandwidth)
+    target = rc->max_frame_bandwidth;
+  return target;
 }
 
 // Update the buffer level: leaky bucket model.
-void vp9_update_buffer_level(VP9_COMP *cpi, int encoded_frame_size) {
+static void update_buffer_level(VP9_COMP *cpi, int encoded_frame_size) {
   const VP9_COMMON *const cm = &cpi->common;
   const VP9_CONFIG *oxcf = &cpi->oxcf;
   RATE_CONTROL *const rc = &cpi->rc;
@@ -242,7 +258,7 @@ void vp9_update_buffer_level(VP9_COMP *cpi, int encoded_frame_size) {
   rc->buffer_level = MIN(rc->bits_off_target, oxcf->maximum_buffer_size);
 }
 
-int vp9_drop_frame(VP9_COMP *cpi) {
+int vp9_rc_drop_frame(VP9_COMP *cpi) {
   const VP9_CONFIG *oxcf = &cpi->oxcf;
   RATE_CONTROL *const rc = &cpi->rc;
 
@@ -281,53 +297,6 @@ int vp9_drop_frame(VP9_COMP *cpi) {
   }
 }
 
-static void calc_pframe_target_size(VP9_COMP *const cpi) {
-  RATE_CONTROL *const rc = &cpi->rc;
-  const VP9_CONFIG *const oxcf = &cpi->oxcf;
-  int min_frame_target;
-  rc->this_frame_target = rc->per_frame_bandwidth;
-
-  if (cpi->pass == 0 && oxcf->end_usage == USAGE_STREAM_FROM_SERVER) {
-    // Need to decide how low min_frame_target should be for 1-pass CBR.
-    // For now, use: cpi->rc.av_per_frame_bandwidth / 16:
-    min_frame_target = MAX(rc->av_per_frame_bandwidth >> 4,
-                           FRAME_OVERHEAD_BITS);
-    if (rc->this_frame_target < min_frame_target)
-      rc->this_frame_target = min_frame_target;
-    return;
-  }
-
-  // Check that the total sum of adjustments is not above the maximum allowed.
-  // That is, having allowed for the KF and GF penalties, we have not pushed
-  // the current inter-frame target too low. If the adjustment we apply here is
-  // not capable of recovering all the extra bits we have spent in the KF or GF,
-  // then the remainder will have to be recovered over a longer time span via
-  // other buffer / rate control mechanisms.
-  min_frame_target = MAX(rc->min_frame_bandwidth,
-                         rc->av_per_frame_bandwidth >> 5);
-
-  if (rc->this_frame_target < min_frame_target)
-    rc->this_frame_target = min_frame_target;
-
-  // Adjust target frame size for Golden Frames:
-  if (cpi->refresh_golden_frame) {
-    // If we are using alternate ref instead of gf then do not apply the boost
-    // It will instead be applied to the altref update
-    // Jims modified boost
-    if (!rc->source_alt_ref_active) {
-      // The spend on the GF is defined in the two pass code
-      // for two pass encodes
-      rc->this_frame_target = rc->per_frame_bandwidth;
-    } else {
-      // 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.
-      rc->this_frame_target = 0;
-    }
-  }
-}
-
 static double get_rate_correction_factor(const VP9_COMP *cpi) {
   if (cpi->common.frame_type == KEY_FRAME) {
     return cpi->rc.key_frame_rate_correction_factor;
@@ -899,24 +868,14 @@ void vp9_rc_compute_frame_size_bounds(const VP9_COMP *cpi,
   }
 }
 
-// return of 0 means drop frame
-int vp9_rc_pick_frame_size_target(VP9_COMP *cpi) {
+void vp9_rc_set_frame_target(VP9_COMP *cpi, int target) {
   const VP9_COMMON *const cm = &cpi->common;
   RATE_CONTROL *const rc = &cpi->rc;
 
-  if (cm->frame_type == KEY_FRAME)
-    calc_iframe_target_size(cpi);
-  else
-    calc_pframe_target_size(cpi);
-
-  // Clip the frame target to the maximum allowed value.
-  if (rc->this_frame_target > rc->max_frame_bandwidth)
-    rc->this_frame_target = rc->max_frame_bandwidth;
-
+  rc->this_frame_target = target;
   // Target rate per SB64 (including partial SB64s.
   rc->sb64_target_rate = ((int64_t)rc->this_frame_target * 64 * 64) /
                              (cm->width * cm->height);
-  return 1;
 }
 
 static void update_alt_ref_frame_stats(VP9_COMP *cpi) {
@@ -960,6 +919,8 @@ static void update_golden_frame_stats(VP9_COMP *cpi) {
 void vp9_rc_postencode_update(VP9_COMP *cpi, uint64_t bytes_used) {
   VP9_COMMON *const cm = &cpi->common;
   RATE_CONTROL *const rc = &cpi->rc;
+
+  cm->last_frame_type = cm->frame_type;
   // Update rate control heuristics
   rc->projected_frame_size = (bytes_used << 3);
 
@@ -1002,7 +963,7 @@ void vp9_rc_postencode_update(VP9_COMP *cpi, uint64_t bytes_used) {
     rc->last_boosted_qindex = cm->base_qindex;
   }
 
-  vp9_update_buffer_level(cpi, rc->projected_frame_size);
+  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.
@@ -1024,22 +985,6 @@ void vp9_rc_postencode_update(VP9_COMP *cpi, uint64_t bytes_used) {
   rc->total_target_vs_actual += (rc->this_frame_target -
                                  rc->projected_frame_size);
 
-#ifndef DISABLE_RC_LONG_TERM_MEM
-  // Update bits left to the kf and gf groups to account for overshoot or
-  // undershoot on these frames
-  if (cm->frame_type == KEY_FRAME) {
-    cpi->twopass.kf_group_bits += cpi->rc.this_frame_target -
-                                  cpi->rc.projected_frame_size;
-
-    cpi->twopass.kf_group_bits = MAX(cpi->twopass.kf_group_bits, 0);
-  } else if (cpi->refresh_golden_frame || cpi->refresh_alt_ref_frame) {
-    cpi->twopass.gf_group_bits += cpi->rc.this_frame_target -
-                                  cpi->rc.projected_frame_size;
-
-    cpi->twopass.gf_group_bits = MAX(cpi->twopass.gf_group_bits, 0);
-  }
-#endif
-
   if (cpi->oxcf.play_alternate && cpi->refresh_alt_ref_frame &&
       (cm->frame_type != KEY_FRAME))
     // Update the alternate reference frame stats as appropriate.
@@ -1057,6 +1002,205 @@ void vp9_rc_postencode_update(VP9_COMP *cpi, uint64_t bytes_used) {
 }
 
 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->common.last_frame_type = cpi->common.frame_type;
   cpi->rc.frames_since_key++;
   cpi->rc.frames_to_key--;
 }
+
+void vp9_rc_get_svc_params(VP9_COMP *cpi) {
+  VP9_COMMON *const cm = &cpi->common;
+  if ((cm->current_video_frame == 0) ||
+      (cm->frame_flags & FRAMEFLAGS_KEY) ||
+      (cpi->oxcf.auto_key && (cpi->rc.frames_since_key %
+                              cpi->key_frame_frequency == 0))) {
+    cm->frame_type = KEY_FRAME;
+    cpi->rc.source_alt_ref_active = 0;
+  } else {
+    cm->frame_type = INTER_FRAME;
+  }
+  cpi->rc.frames_till_gf_update_due = INT_MAX;
+  cpi->rc.baseline_gf_interval = INT_MAX;
+}
+
+static int test_for_kf_one_pass(VP9_COMP *cpi) {
+  // Placeholder function for auto key frame
+  return 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) {
+  const RATE_CONTROL *rc = &cpi->rc;
+  int target = rc->av_per_frame_bandwidth;
+  target = vp9_rc_clamp_pframe_target_size(cpi, target);
+  return target;
+}
+
+static int calc_iframe_target_size_one_pass_vbr(const VP9_COMP *const cpi) {
+  const RATE_CONTROL *rc = &cpi->rc;
+  int target = rc->av_per_frame_bandwidth * 8;
+  target = vp9_rc_clamp_iframe_target_size(cpi, target);
+  return target;
+}
+
+void vp9_rc_get_one_pass_vbr_params(VP9_COMP *cpi) {
+  VP9_COMMON *const cm = &cpi->common;
+  int target;
+  if (!cpi->refresh_alt_ref_frame &&
+      (cm->current_video_frame == 0 ||
+       cm->frame_flags & FRAMEFLAGS_KEY ||
+       cpi->rc.frames_to_key == 0 ||
+       (cpi->oxcf.auto_key && test_for_kf_one_pass(cpi)))) {
+    cm->frame_type = KEY_FRAME;
+    cpi->rc.this_key_frame_forced = cm->current_video_frame != 0 &&
+                                    cpi->rc.frames_to_key == 0;
+    cpi->rc.frames_to_key = cpi->key_frame_frequency;
+    cpi->rc.kf_boost = DEFAULT_KF_BOOST;
+    cpi->rc.source_alt_ref_active = 0;
+    if (cm->current_video_frame == 0) {
+      cpi->rc.active_worst_quality = cpi->rc.worst_quality;
+    } else {
+      // Choose active worst quality twice as large as the last q.
+      cpi->rc.active_worst_quality = cpi->rc.last_q[KEY_FRAME] * 2;
+      if (cpi->rc.active_worst_quality > cpi->rc.worst_quality)
+        cpi->rc.active_worst_quality = cpi->rc.worst_quality;
+    }
+  } else {
+    cm->frame_type = INTER_FRAME;
+    if (cm->current_video_frame == 1) {
+      cpi->rc.active_worst_quality = cpi->rc.worst_quality;
+    } else {
+      // Choose active worst quality twice as large as the last q.
+      cpi->rc.active_worst_quality = cpi->rc.last_q[INTER_FRAME] * 2;
+      if (cpi->rc.active_worst_quality > cpi->rc.worst_quality)
+        cpi->rc.active_worst_quality = cpi->rc.worst_quality;
+    }
+  }
+  if (cpi->rc.frames_till_gf_update_due == 0) {
+    cpi->rc.baseline_gf_interval = DEFAULT_GF_INTERVAL;
+    cpi->rc.frames_till_gf_update_due = cpi->rc.baseline_gf_interval;
+    // NOTE: frames_till_gf_update_due must be <= frames_to_key.
+    if (cpi->rc.frames_till_gf_update_due > cpi->rc.frames_to_key)
+      cpi->rc.frames_till_gf_update_due = cpi->rc.frames_to_key;
+    cpi->refresh_golden_frame = 1;
+    cpi->rc.source_alt_ref_pending = USE_ALTREF_FOR_ONE_PASS;
+    cpi->rc.gfu_boost = 2000;
+  }
+  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);
+}
+
+// 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_CONFIG *oxcf = &cpi->oxcf;
+  const RATE_CONTROL *rc = &cpi->rc;
+  int active_worst_quality = rc->active_worst_quality;
+  // Maximum limit for down adjustment, ~20%.
+  int max_adjustment_down = active_worst_quality / 5;
+  // Buffer level below which we push active_worst to worst_quality.
+  int critical_level = oxcf->optimal_buffer_level >> 2;
+  int adjustment = 0;
+  int buff_lvl_step = 0;
+  if (rc->buffer_level > oxcf->optimal_buffer_level) {
+    // Adjust down.
+    if (max_adjustment_down) {
+      buff_lvl_step = (int)((oxcf->maximum_buffer_size -
+          oxcf->optimal_buffer_level) / max_adjustment_down);
+      if (buff_lvl_step)
+        adjustment = (int)((rc->buffer_level - oxcf->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 = (oxcf->optimal_buffer_level - critical_level);
+      if (buff_lvl_step) {
+        adjustment = (rc->worst_quality - rc->avg_frame_qindex[INTER_FRAME]) *
+                         (oxcf->optimal_buffer_level - rc->buffer_level) /
+                             buff_lvl_step;
+      }
+      active_worst_quality = rc->avg_frame_qindex[INTER_FRAME] + adjustment;
+    }
+  } else {
+    // Set to worst_quality if buffer is below critical level.
+    active_worst_quality = rc->worst_quality;
+  }
+  return active_worst_quality;
+}
+
+static int calc_pframe_target_size_one_pass_cbr(const VP9_COMP *cpi) {
+  const VP9_CONFIG *oxcf = &cpi->oxcf;
+  const RATE_CONTROL *rc = &cpi->rc;
+  int target = rc->av_per_frame_bandwidth;
+  const int min_frame_target = MAX(rc->av_per_frame_bandwidth >> 4,
+                                   FRAME_OVERHEAD_BITS);
+  const int64_t diff = oxcf->optimal_buffer_level - rc->buffer_level;
+  const int one_pct_bits = 1 + oxcf->optimal_buffer_level / 100;
+  if (diff > 0) {
+    // Lower the target bandwidth for this frame.
+    const int pct_low = 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 = MIN(-diff / one_pct_bits, oxcf->over_shoot_pct);
+    target += (target * pct_high) / 200;
+  }
+  if (target < min_frame_target)
+    target = min_frame_target;
+  return target;
+}
+
+static int calc_iframe_target_size_one_pass_cbr(const VP9_COMP *cpi) {
+  int target;
+  const RATE_CONTROL *rc = &cpi->rc;
+  if (cpi->common.current_video_frame == 0) {
+    target = cpi->oxcf.starting_buffer_level / 2;
+  } else {
+    int initial_boost = 32;
+    int kf_boost = MAX(initial_boost, (int)(2 * cpi->output_framerate - 16));
+    if (rc->frames_since_key < cpi->output_framerate / 2) {
+      kf_boost = (int)(kf_boost * rc->frames_since_key /
+                       (cpi->output_framerate / 2));
+    }
+    target = ((16 + kf_boost) * rc->av_per_frame_bandwidth) >> 4;
+  }
+  return target;
+}
+
+void vp9_rc_get_one_pass_cbr_params(VP9_COMP *cpi) {
+  VP9_COMMON *const cm = &cpi->common;
+  int target;
+  if ((cm->current_video_frame == 0 ||
+      cm->frame_flags & FRAMEFLAGS_KEY ||
+      cpi->rc.frames_to_key == 0 ||
+      (cpi->oxcf.auto_key && test_for_kf_one_pass(cpi)))) {
+    cm->frame_type = KEY_FRAME;
+    cpi->rc.this_key_frame_forced = cm->current_video_frame != 0 &&
+                                    cpi->rc.frames_to_key == 0;
+    cpi->rc.frames_to_key = cpi->key_frame_frequency;
+    cpi->rc.kf_boost = DEFAULT_KF_BOOST;
+    cpi->rc.source_alt_ref_active = 0;
+    target = calc_iframe_target_size_one_pass_cbr(cpi);
+    cpi->rc.active_worst_quality = cpi->rc.worst_quality;
+  } else {
+    cm->frame_type = INTER_FRAME;
+    target = calc_pframe_target_size_one_pass_cbr(cpi);
+    cpi->rc.active_worst_quality =
+        calc_active_worst_quality_one_pass_cbr(cpi);
+  }
+  vp9_rc_set_frame_target(cpi, target);
+  // Don't use gf_update by default in CBR mode.
+  cpi->rc.frames_till_gf_update_due = INT_MAX;
+  cpi->rc.baseline_gf_interval = INT_MAX;
+}
diff --git a/vp9/encoder/vp9_ratectrl.h b/vp9/encoder/vp9_ratectrl.h
index eba4b7a92..8ff567dd5 100644
--- a/vp9/encoder/vp9_ratectrl.h
+++ b/vp9/encoder/vp9_ratectrl.h
@@ -46,7 +46,6 @@ typedef struct {
   unsigned int source_alt_ref_active;
   unsigned int is_src_frame_alt_ref;
 
-  int per_frame_bandwidth;        // Current section per frame bandwidth target
   int av_per_frame_bandwidth;     // Average frame size target for clip
   int min_frame_bandwidth;        // Minimum allocation used for any frame
   int max_frame_bandwidth;        // Maximum burst rate allowed for a frame.
@@ -89,16 +88,53 @@ void vp9_setup_inter_frame(struct VP9_COMP *cpi);
 
 double vp9_convert_qindex_to_q(int qindex);
 
-// Updates rate correction factors
-void vp9_rc_update_rate_correction_factors(struct VP9_COMP *cpi, int damp_var);
-
 // initialize luts for minq
 void vp9_rc_init_minq_luts(void);
 
-// return of 0 means drop frame
-// Changes only rc.this_frame_target and rc.sb64_rate_target
-int vp9_rc_pick_frame_size_target(struct VP9_COMP *cpi);
+// Generally at the high level, the following flow is expected
+// to be enforced for rate control:
+// First call per frame, one of:
+//   vp9_rc_get_one_pass_vbr_params()
+//   vp9_rc_get_one_pass_cbr_params()
+//   vp9_rc_get_svc_params()
+//   vp9_rc_get_first_pass_params()
+//   vp9_rc_get_second_pass_params()
+// depending on the usage to set the rate control encode parameters desired.
+//
+// Then, call encode_frame_to_data_rate() to perform the
+// actual encode. This function will in turn call encode_frame()
+// one or more times, followed by one of:
+//   vp9_rc_postencode_update()
+//   vp9_rc_postencode_update_drop_frame()
+//
+// The majority of rate control parameters are only expected
+// to be set in the vp9_rc_get_..._params() functions and
+// updated during the vp9_rc_postencode_update...() functions.
+// The only exceptions are vp9_rc_drop_frame() and
+// vp9_rc_update_rate_correction_factors() functions.
 
+// Functions to set parameters for encoding before the actual
+// encode_frame_to_data_rate() function.
+void vp9_rc_get_one_pass_vbr_params(struct VP9_COMP *cpi);
+void vp9_rc_get_one_pass_cbr_params(struct VP9_COMP *cpi);
+void vp9_rc_get_svc_params(struct VP9_COMP *cpi);
+
+// Post encode update of the rate control parameters based
+// on bytes used
+void vp9_rc_postencode_update(struct VP9_COMP *cpi,
+                              uint64_t bytes_used);
+// Post encode update of the rate control parameters for dropped frames
+void vp9_rc_postencode_update_drop_frame(struct VP9_COMP *cpi);
+
+// Updates rate correction factors
+// Changes only the rate correction factors in the rate control structure.
+void vp9_rc_update_rate_correction_factors(struct VP9_COMP *cpi, int damp_var);
+
+// Decide if we should drop this frame: For 1-pass CBR.
+// Changes only the decimation count in the rate control structure
+int vp9_rc_drop_frame(struct VP9_COMP *cpi);
+
+// Computes frame size bounds.
 void vp9_rc_compute_frame_size_bounds(const struct VP9_COMP *cpi,
                                       int this_frame_target,
                                       int *frame_under_shoot_limit,
@@ -113,26 +149,18 @@ int vp9_rc_pick_q_and_adjust_q_bounds(const struct VP9_COMP *cpi,
 int vp9_rc_regulate_q(const struct VP9_COMP *cpi, int target_bits_per_frame,
                       int active_best_quality, int active_worst_quality);
 
-// Post encode update of the rate control parameters based
-// on bytes used
-void vp9_rc_postencode_update(struct VP9_COMP *cpi,
-                              uint64_t bytes_used);
-// for dropped frames
-void vp9_rc_postencode_update_drop_frame(struct VP9_COMP *cpi);
-
-// estimates bits per mb for a given qindex and correction factor
+// Estimates bits per mb for a given qindex and correction factor.
 int vp9_rc_bits_per_mb(FRAME_TYPE frame_type, int qindex,
                        double correction_factor);
 
-// Post encode update of the rate control parameters for 2-pass
-void vp9_twopass_postencode_update(struct VP9_COMP *cpi,
-                                   uint64_t bytes_used);
-
-// Decide if we should drop this frame: For 1-pass CBR.
-int vp9_drop_frame(struct VP9_COMP *cpi);
-
-// Update the buffer level.
-void vp9_update_buffer_level(struct VP9_COMP *cpi, int encoded_frame_size);
+// Clamping utilities for bitrate targets for iframes and pframes.
+int vp9_rc_clamp_iframe_target_size(const struct VP9_COMP *const cpi,
+                                    int target);
+int vp9_rc_clamp_pframe_target_size(const struct VP9_COMP *const cpi,
+                                    int target);
+// Utility to set frame_target into the RATE_CONTROL structure
+// This function is called only from the vp9_rc_get_..._params() functions.
+void vp9_rc_set_frame_target(struct VP9_COMP *cpi, int target);
 
 #ifdef __cplusplus
 }  // extern "C"