From: Jerome Jiang <jianj@google.com>
Date: Mon, 14 Nov 2016 18:22:00 +0000 (-0800)
Subject: vp9: Speed 8: Turn off 4x4avg for low-res non-key frames.
X-Git-Tag: v1.6.1~95
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=eff68a3a4df99b8f475a1e3e5eb842bcb928fe00;p=libvpx

vp9: Speed 8: Turn off 4x4avg for low-res non-key frames.

Changes only affects speed = 8 for low resolutions.

Metrics for avgPSNR/SSIM on rtc_derf (low resolutions) show loss of
0.5/0.6%.
On Nexus 6, the encoding time is reduced by ~5.9% on average across all
low-res clips.
Visually little/no change on rtc_derf clips.

Change-Id: I68dd50e558d72dcc1af8317d224bfae5e3bd872d
---

diff --git a/vp9/encoder/vp9_encodeframe.c b/vp9/encoder/vp9_encodeframe.c
index 3ab05375f..7cf7b90db 100644
--- a/vp9/encoder/vp9_encodeframe.c
+++ b/vp9/encoder/vp9_encodeframe.c
@@ -834,8 +834,8 @@ static int choose_partitioning(VP9_COMP *cpi, const TileInfo *const tile,
     }
   }
 
-  threshold_4x4avg =
-      (cpi->oxcf.speed < 8) ? thresholds[1] << 1 : thresholds[2] >> 1;
+  // For non keyframes, disable 4x4 average for low resolution when speed = 8
+  threshold_4x4avg = (cpi->oxcf.speed < 8) ? thresholds[1] << 1 : INT64_MAX;
 
   memset(x->variance_low, 0, sizeof(x->variance_low));