tree 6caa9cef7cdfe7a08f04f02cbc99762ebab69e8f
parent 3f9c45d24b9dde7960af758189550546d53b23b3
author Jingning Han <jingning@google.com> 1564633120 -0700
committer Jingning Han <jingning@google.com> 1565893834 +0000

Use top-down GOP rate allocation

Simplify the GOP rate allocation logic. Use a top-down frame rate
allocation approach. Decide the ARFs frame size from base layer
towards higher layers using the arf boost factor. The vbr coding
performance for low/mid res set remains neutral. It helps the ugc
set a bit more since the clips are less stationary than standard
test sets. Tested in speed 1 with 150 frames, the vbr coding stats
are changed:

     avg PSNR    overall PSNR    SSIM    PSNR-HVS
low  -0.07%        -0.04%        0.04%    -0.11%
mid  -0.04%        -0.04%        0.10%    -0.12%
ugc  -0.21%        -0.23%       -0.06%    -0.32%

STATS_CHANGED

Change-Id: I992cea228a57d162428edf8d7f400ea9421cd2cb