commit 4ed47d01901248a93c525a5f7c75015cf605cbff
author Alex Loiko <aleloi@webrtc.org> Wed Apr 04 13:05:57 2018
committer Commit Bot <commit-bot@chromium.org> Wed Apr 04 18:23:55 2018
tree 245fb3ede6db3ae6efadda0911863081a3d358f9
parent 0a713b63eded9b8b21339e3c9c4654b69760be00

Noise level estimation for AGC2.

We put back the old noise estimator from LevelController. We add a few
new unit tests. We also re-arrange the code so that it fits with how
it is used in AGC2. The differences are:

1. The NoiseLevelEstimator is now fully self-contained.
2. The NoiseLevelEstimator is responsible for calling SignalClassifier
   and computing the signal energy. Previously the signal type and
   energy were used in several places. It made sense to compute the
   values independently of the noise calculation.
3. Re-initialization doesn't have to be done by the caller.
4. The interface is AudioFrameView instead of AudioBuffer.

# Bots are green, nothing should break internal stuff
NOTRY=True

Bug: webrtc:7494
Change-Id: I442bdbbeb3796eb2518e96000aec9dc5a039ae6d
Reviewed-on: https://webrtc-review.googlesource.com/66380
Commit-Queue: Alex Loiko <aleloi@webrtc.org>
Reviewed-by: Sam Zackrisson <saza@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#22738}