From a047e7cdf8a00701df141e8d72937541f4a88e0d Mon Sep 17 00:00:00 2001
From: Marco <marpan@google.com>
Date: Wed, 3 Dec 2014 10:19:54 -0800
Subject: [PATCH] Increase delta-qp for aq=3 mode, after key frame.

For a few refresh periods after key frame, use large qp-delta
to increase quality ramp-up.

Change-Id: Ib5a150fb2dfa6bafd0d4e6b5d28dfd0724b61319
---
 vp9/encoder/vp9_aq_cyclicrefresh.c | 17 ++++++++++++++---
 vp9/encoder/vp9_aq_cyclicrefresh.h |  3 +++
 vp9/encoder/vp9_ratectrl.c         | 11 +++++++++++
 3 files changed, 28 insertions(+), 3 deletions(-)

diff --git a/vp9/encoder/vp9_aq_cyclicrefresh.c b/vp9/encoder/vp9_aq_cyclicrefresh.c
index bc68b3756..5f1c8ce74 100644
--- a/vp9/encoder/vp9_aq_cyclicrefresh.c
+++ b/vp9/encoder/vp9_aq_cyclicrefresh.c
@@ -319,6 +319,20 @@ void vp9_cyclic_refresh_update_map(VP9_COMP *const cpi) {
   cr->sb_index = i;
 }
 
+// Set/update global/frame level cyclic refresh parameters.
+void vp9_cyclic_refresh_update_parameters(VP9_COMP *const cpi) {
+  const RATE_CONTROL *const rc = &cpi->rc;
+  CYCLIC_REFRESH *const cr = cpi->cyclic_refresh;
+  cr->percent_refresh = 10;
+  // Use larger delta-qp (increase rate_ratio_qdelta) for first few (~4)
+  // periods of the refresh cycle, after a key frame. This corresponds to ~40
+  // frames with cr->percent_refresh = 10.
+  if (rc->frames_since_key <  40)
+    cr->rate_ratio_qdelta = 3.0;
+  else
+    cr->rate_ratio_qdelta = 2.0;
+}
+
 // Setup cyclic background refresh: set delta q and segmentation map.
 void vp9_cyclic_refresh_setup(VP9_COMP *const cpi) {
   VP9_COMMON *const cm = &cpi->common;
@@ -343,9 +357,6 @@ void vp9_cyclic_refresh_setup(VP9_COMP *const cpi) {
     int qindex2;
     const double q = vp9_convert_qindex_to_q(cm->base_qindex, cm->bit_depth);
     vp9_clear_system_state();
-    // Some of these parameters may be set via codec-control function later.
-    cr->percent_refresh = 10;
-    cr->rate_ratio_qdelta = 2.0;
     cr->max_qdelta_perc = 50;
     cr->min_block_size = BLOCK_8X8;
     cr->time_for_refresh = 0;
diff --git a/vp9/encoder/vp9_aq_cyclicrefresh.h b/vp9/encoder/vp9_aq_cyclicrefresh.h
index 3fc677646..656d7605b 100644
--- a/vp9/encoder/vp9_aq_cyclicrefresh.h
+++ b/vp9/encoder/vp9_aq_cyclicrefresh.h
@@ -53,6 +53,9 @@ void vp9_cyclic_refresh_update__map(struct VP9_COMP *const cpi);
 // Update the actual number of blocks that were applied the segment delta q.
 void vp9_cyclic_refresh_update_actual_count(struct VP9_COMP *const cpi);
 
+// Set/update global/frame level refresh parameters.
+void vp9_cyclic_refresh_update_parameters(struct VP9_COMP *const cpi);
+
 // Setup cyclic background refresh: set delta q and segmentation map.
 void vp9_cyclic_refresh_setup(struct VP9_COMP *const cpi);
 
diff --git a/vp9/encoder/vp9_ratectrl.c b/vp9/encoder/vp9_ratectrl.c
index e96c9046d..37b6718bf 100644
--- a/vp9/encoder/vp9_ratectrl.c
+++ b/vp9/encoder/vp9_ratectrl.c
@@ -1483,6 +1483,12 @@ void vp9_rc_get_svc_params(VP9_COMP *cpi) {
       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;
@@ -1516,6 +1522,11 @@ void vp9_rc_get_one_pass_cbr_params(VP9_COMP *cpi) {
     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