commit 86684960b31643f5aec924fb800742d37b594e68
author Sergey Silkin <ssilkin@webrtc.org> Wed Mar 28 17:32:37 2018
committer Commit Bot <commit-bot@chromium.org> Thu Mar 29 10:16:47 2018
tree fadd902dd7e8c3b834fa3e965042d4404caa778b
parent 002e710d078d87678a4daf3ad4af3a0038020eb9

Adding layering configurator and rate allocator for VP9 SVC.

The configurator decides number of spatial layers, their resolution
and bitrate thresholds based on given input resolution and maximum
number of spatial layers.

The allocator distributes available bitrate across spatial and
temporal layers. If there is not enough bitrate to provide acceptable
quality for all spatial layers allocator disables enhancement layers
one by one until the condition is met or number of layers is reduced
to one.

VP9 SVC related unit tests have been updated. Input resolution and
bitrate in these tests have been increased to the level enough to
provide desirable number of spatial layers.

Bug: webrtc:8518
Change-Id: I9df790920227c7f7dd4d42a50a856c22f0f4389b
Reviewed-on: https://webrtc-review.googlesource.com/60340
Commit-Queue: Sergey Silkin <ssilkin@webrtc.org>
Reviewed-by: Erik Språng <sprang@webrtc.org>
Reviewed-by: Stefan Holmer <stefan@webrtc.org>
Reviewed-by: Rasmus Brandt <brandtr@webrtc.org>
Reviewed-by: Michael Horowitz <mhoro@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#22672}