From: Marco Paniconi <marpan@google.com>
Date: Wed, 6 Jun 2018 22:16:14 +0000 (-0700)
Subject: vp9-svc: Enable use of second temporal reference for SVC.
X-Git-Tag: v1.8.0~637
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=4640c2f58346160a1aedafc323b3d1f322f71e5d;p=libvpx

vp9-svc: Enable use of second temporal reference for SVC.

When inter-layer is disabled on INTER frames, this will allow
use of a second (longer term) temporal reference for SVC.

Only enabled on highest resolution spatial layer.

Average gains of ~4% on RTC set, speed decrease of about ~2%.

Change-Id: I3c2d415653c448eb7269c828e120fe8bb2ef3f97
---

diff --git a/vp9/encoder/vp9_svc_layercontext.c b/vp9/encoder/vp9_svc_layercontext.c
index f5baa7cdd..a72083b61 100644
--- a/vp9/encoder/vp9_svc_layercontext.c
+++ b/vp9/encoder/vp9_svc_layercontext.c
@@ -33,7 +33,7 @@ void vp9_init_layer_context(VP9_COMP *const cpi) {
   svc->force_zero_mode_spatial_ref = 0;
   svc->use_base_mv = 0;
   svc->use_partition_reuse = 0;
-  svc->use_longterm_ref = 0;
+  svc->use_longterm_ref = 1;
   svc->use_longterm_ref_current_layer = 0;
   svc->scaled_temp_is_alloc = 0;
   svc->scaled_one_half = 0;