commit 6f2fcb4962e9488e0c251c9315c5f2a5480acdde
author Alex Loiko <aleloi@webrtc.org> Wed Mar 14 12:27:05 2018 +0100
committer Commit Bot <commit-bot@chromium.org> Thu Mar 15 10:51:06 2018 +0000
tree dcc60ec02e7ac194104d4baaf0d83582e4e022bf
parent aaa882cea5dc42532e44d8ed9b1eaeb064a249a1

Add more Audio Mixer and Fixed Gain Controller metrics.

We want to know how the AudioMixer is used and how FixedGainController
behaves.

The WebRTC.Audio.Agc2.FixedDigitalGainCurveRegion.* metrics measures
how often the input level hits different regions of the Fixed Gain
Controller gain curve (when the limiter is enabled). They also measure
how long the metrics stay in different regions. They are related to
WebRTC.Audio.ApmCaptureOutputLevelPeakRms, but the new metrics measure
the level before any processing done in APM.

The AudioMixer mixes incoming audio streams. Their number should be
mostly constant, and often some of them could be muted. The metrics
WebRTC.Audio.AudioMixer.NumIncomingStreams,
WebRTC.Audio.AudioMixer.NumIncomingActiveStreams log the number of
incoming stream and how many are not muted. We currently don't have
any stats related to that.

The metric WebRTC.Audio.AudioMixer.MixingRate logs the rate selected
for mixing. The rate can sometimes be inferred from
WebRTC.Audio.Encoder.CodecType. But that metric measures encoding and
not decoding, and codecs don't always map to rates.

See also accompanying Chromium CL
https://chromium-review.googlesource.com/c/chromium/src/+/939473

Bug: webrtc:8925
Change-Id: Ib1405877fc1b39e5d2f0ceccba04434813f20b0d
Reviewed-on: https://webrtc-review.googlesource.com/57740
Reviewed-by: Alessio Bazzica <alessiob@webrtc.org>
Commit-Queue: Alex Loiko <aleloi@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#22443}