commit d62d804e647e6726abe23726e43cac622713da94
author Jingning Han <jingning@google.com> Tue Sep 02 17:32:12 2014 -0700
committer Jingning Han <jingning@google.com> Wed Sep 03 15:28:01 2014 -0700
tree e9cd37a80fc2bfc99d22006d5081e1f0a9bdad2d
parent 33176fef872c5d812d7ce8f9875d5166de460c5d

Speed up compound inter prediction mode check

This commit allows the encoder to store outcomes of single reference
frame modes and compares them to decide if the inter prediction
filter, forward transform, and quantization can be skipped.

The compression performance of speed 3 is down
derf  -0.364%
stdhd -0.198%

For test sequences, the speed 3 runtime is reduced
highway CIF 100 kbps, 51976 ms -> 45033 ms, 13% speed-up
stockholm 720p 1000 kbps, 71826 ms -> 67838 ms, 5.5% speed-up
pedestrian 1080p 2000 kbps, 154924 ms -> 150702 ms, 2.6% speed-up

Change-Id: I5aa26f918d2b4b5197a2c0afa2779319f1c88e44