commit fcf5fa2723524fe2beabd2b0ac1d4409a2284405
author Zoe Liu <zoeliu@google.com> Mon Jun 26 16:00:38 2017 -0700
committer Zoe Liu <zoeliu@google.com> Wed Jul 12 00:20:35 2017 +0000
tree 7afe2e2695de320f7b6046b55676ba4f097753b3
parent 9c52192b10b054559edb6e34af9a946e2868f2d7

Further work on ext-comp-refs for ref frame coding

(1) Work with var-refs to remove redundant bits in ref frame
    coding;
(2) Add a new uni-directional compound reference pair:
    (LAST_FRAME, LAST3_FRAME);
(3) Redesign the contexts for encoding uni-directional reference frame
    pairs;
(4) Use aom_entropy_optimizer to collect stats for all the default
    probability setups related to the coding of reference frames.

Compared against the baseline (default enabled tools excluding ext-tx
and global-motion for encoder speed concern) with one-sided-compound,
the coding gain of ext-comp-refs + var-refs - one-sided-compound is:

lowres: avg_psnr -0.385%; ovr_psnr -0.378% ssim -0.344%
midres: avg_psnr -0.466%; ovr_psnr -0.447% ssim -0.513%

AWCY - High Latency:
   PSNR | PSNR Cb | PSNR Cr | PSNR HVS |    SSIM | MS SSIM | CIEDE 2000
-0.2758 | -0.1526 | -0.0965 |  -0.2581 | -0.2492 | -0.2534 |    -0.2118

AWCY - Low Latency:
   PSNR | PSNR Cb | PSNR Cr | PSNR HVS |    SSIM | MS SSIM | CIEDE 2000
-1.0467 | -1.4500 | -0.9732 |  -0.9928 | -1.0407 | -1.0180 |    -1.0049

Compared against the baseline (default enabled tools excluding ext-tx
and global-motion for encoder speed concern) without
one-sided-compound, the coding gain of
ext-comp-refs + var-refs - one-sided-compound is:

lowres: avg_psnr -0.875%; ovr_psnr -0.877% ssim -0.895%
midres: avg_psnr -0.824%; ovr_psnr -0.802% ssim -0.843%

Change-Id: I8de774c9a74c20632ea93ccb0c17779fa94431cb

av1/encoder/encodeframe.c

diff --git a/av1/encoder/encodeframe.c b/av1/encoder/encodeframe.c
index 32d244c..7d3d44e 100644
--- a/av1/encoder/encodeframe.c
+++ b/av1/encoder/encodeframe.c
@@ -1613,17 +1613,21 @@
           // TODO(zoeliu): Temporarily turn off uni-directional comp refs
           assert(comp_ref_type == BIDIR_COMP_REFERENCE);
 #endif  // !USE_UNI_COMP_REFS
-          counts->comp_ref_type[av1_get_comp_reference_type_context(cm, xd)]
+          counts->comp_ref_type[av1_get_comp_reference_type_context(xd)]
                                [comp_ref_type]++;
 
           if (comp_ref_type == UNIDIR_COMP_REFERENCE) {
             const int bit = (ref0 == BWDREF_FRAME);
-            counts->uni_comp_ref[av1_get_pred_context_uni_comp_ref_p(cm, xd)][0]
+            counts->uni_comp_ref[av1_get_pred_context_uni_comp_ref_p(xd)][0]
                                 [bit]++;
             if (!bit) {
-              const int bit1 = (ref1 == GOLDEN_FRAME);
-              counts->uni_comp_ref[av1_get_pred_context_uni_comp_ref_p1(cm, xd)]
-                                  [1][bit1]++;
+              const int bit1 = (ref1 == LAST3_FRAME || ref1 == GOLDEN_FRAME);
+              counts->uni_comp_ref[av1_get_pred_context_uni_comp_ref_p1(xd)][1]
+                                  [bit1]++;
+              if (bit1) {
+                counts->uni_comp_ref[av1_get_pred_context_uni_comp_ref_p2(xd)]
+                                    [2][ref1 == GOLDEN_FRAME]++;
+              }
             }
           } else {
 #endif  // CONFIG_EXT_COMP_REFS