Enable asymptotic closed-loop encoding decision

This commit enables asymptotic closed-loop encoding decision for
the key frame and alternate reference frame. It follows the regular
rate control scheme, but leaves out additional iteration on the
updated frame level probability model. It is enabled for speed 0.

The compression performance is improved:

lowres 0.2%
midres 0.35%
hdres  0.4%

Change-Id: I905ffa057c9a1ef2e90ef87c9723a6cf7dbe67cb

diff --git a/vp9/encoder/vp9_encoder.c b/vp9/encoder/vp9_encoder.c
index 2a58003829ca7ac84d5a3f735b61a0e54b7e8151..600ebec9c563deb582b6885df02386194e70b538 100644 (file)
--- a/vp9/encoder/vp9_encoder.c
+++ b/vp9/encoder/vp9_encoder.c
@@ -3238,9 +3238,14 @@ static void encode_with_recode_loop(VP9_COMP *cpi, size_t *size,
   int frame_over_shoot_limit;
   int frame_under_shoot_limit;
   int q = 0, q_low = 0, q_high = 0;
+  int enable_acl;
 
   set_size_independent_vars(cpi);
 
+  enable_acl = cpi->sf.allow_acl
+                   ? (cm->frame_type == KEY_FRAME) || (cm->show_frame == 0)
+                   : 0;
+
   do {
     vpx_clear_system_state();
 
@@ -3335,7 +3340,6 @@ static void encode_with_recode_loop(VP9_COMP *cpi, size_t *size,
       if (!cpi->sf.use_nonrd_pick_mode) vp9_pack_bitstream(cpi, dest, size);
 
       rc->projected_frame_size = (int)(*size) << 3;
-      restore_coding_context(cpi);
 
       if (frame_over_shoot_limit == 0) frame_over_shoot_limit = 1;
     }
@@ -3505,7 +3509,22 @@ static void encode_with_recode_loop(VP9_COMP *cpi, size_t *size,
       ++cpi->tot_recode_hits;
 #endif
     }
+
+    if (cpi->sf.recode_loop >= ALLOW_RECODE_KFARFGF)
+      if (loop || !enable_acl) restore_coding_context(cpi);
   } while (loop);
+
+  if (enable_acl) {
+    vp9_encode_frame(cpi);
+    vpx_clear_system_state();
+    restore_coding_context(cpi);
+    vp9_pack_bitstream(cpi, dest, size);
+
+    vp9_encode_frame(cpi);
+    vpx_clear_system_state();
+
+    restore_coding_context(cpi);
+  }
 }
 
 static int get_ref_frame_flags(const VP9_COMP *cpi) {

diff --git a/vp9/encoder/vp9_speed_features.c b/vp9/encoder/vp9_speed_features.c
index 3e1ed50a6d2a368560bf6e062fe1a940dafcc6e2..6f8ed19097054736364ef28b71ec335cc18ea7d5 100644 (file)
--- a/vp9/encoder/vp9_speed_features.c
+++ b/vp9/encoder/vp9_speed_features.c
@@ -182,6 +182,7 @@ static void set_good_speed_feature(VP9_COMP *cpi, VP9_COMMON *cm,
     sf->mv.subpel_iters_per_step = 1;
     sf->mode_skip_start = 10;
     sf->adaptive_pred_interp_filter = 1;
+    sf->allow_acl = 0;
 
     sf->intra_y_mode_mask[TX_32X32] = INTRA_DC_H_V;
     sf->intra_uv_mode_mask[TX_32X32] = INTRA_DC_H_V;
@@ -309,6 +310,7 @@ static void set_rt_speed_feature(VP9_COMP *cpi, SPEED_FEATURES *sf, int speed,
   sf->use_fast_coef_costing = 1;
   sf->allow_exhaustive_searches = 0;
   sf->exhaustive_searches_thresh = INT_MAX;
+  sf->allow_acl = 0;
 
   if (speed >= 1) {
     sf->allow_txfm_domain_distortion = 1;
@@ -592,6 +594,7 @@ void vp9_set_speed_features_framesize_independent(VP9_COMP *cpi) {
   sf->tx_domain_thresh = 99.0;
   sf->allow_quant_coeff_opt = sf->optimize_coefficients;
   sf->quant_opt_thresh = 99.0;
+  sf->allow_acl = 1;
 
   for (i = 0; i < TX_SIZES; i++) {
     sf->intra_y_mode_mask[i] = INTRA_ALL;

diff --git a/vp9/encoder/vp9_speed_features.h b/vp9/encoder/vp9_speed_features.h
index 6d0b9420a1d0fc00a2a29137f3e3fe33e92d510d..7f83c606fc75ee05ed4ce42e3a115c92d667c993 100644 (file)
--- a/vp9/encoder/vp9_speed_features.h
+++ b/vp9/encoder/vp9_speed_features.h
@@ -244,6 +244,10 @@ typedef struct SPEED_FEATURES {
   int allow_quant_coeff_opt;
   double quant_opt_thresh;
 
+  // Enable asymptotic closed-loop encoding decision for key frame and
+  // alternate reference frames.
+  int allow_acl;
+
   // Use transform domain distortion. Use pixel domain distortion in speed 0
   // and certain situations in higher speed to improve the RD model precision.
   int allow_txfm_domain_distortion;