This change changes mixing to be done at the lowest possible
APM-native rate that does not lead to quality loss. An Audio
Processing-native rate is one of 8, 16, 32, or 48 kHz. Mixing at a
lower sampling rate and avoiding resampling can in many cases lead to
big efficiency improvements, as reported by experiments.
This CL also fixes a design issue with the AudioMixer: audio at
non-native rates is no longer fed to the APM instance which is the
limiter.
NOTRY=True
BUG=webrtc:6346
Review-Url: https://codereview.webrtc.org/2458703002
Cr-Commit-Position: refs/heads/master@{#14980}
The mixer allocates an audio frame for each added data source. This
audio frame was deallocated when a source was removed from the
mixer. Source removal could happen during the mixing, and the existing
locking scheme (and the Clang thread checker) was not sufficient to
prevent a data race.
After this change, the mixer doesn't release its lock until it is
finished with the sources' Audio frames. Since multi-threaded access to
the mixer only happens when a source is added or removed, we believe
that this change wouldn't have any noticeable performance impact.
NOTRY=True
BUG=webrtc:6346
Review-Url: https://codereview.webrtc.org/2439283002
Cr-Commit-Position: refs/heads/master@{#14744}
Simplify the AudioMixer::Source interface and update the mixer
implementation to the new interface.
Instead of asking a mixer source to provide a pointer to an AudioFrame
during each mixing iteration, a mixer should supply a pointer to its
own AudioFrame.
This simplifies lifetime issues as sources do not give away an
internal pointer.
Implementation: when an audio source is added, the mixer allocates a
new AudioFrame. The audio frame is kept together in the internal class
SourceStatus together with the audio source pointer until the source
is removed.
NOTRY=True
BUG=webrtc:6346
Review-Url: https://codereview.webrtc.org/2420913002
Cr-Commit-Position: refs/heads/master@{#14713}
This change is due to an incorrect understanding of the threading
model in Chrome. The new AudioMixer has a thread checker to ensure
that mixing is always done from a single thread. Mixing is done on the
Audio Output Thread. When run in Chrome, it can change. Even if the thread
changes, there is never more than one audio thread, and mixing is done
sequentially.
The threading checks and variable access checks are replaced with
rtc::RaceChecker counterparts.
NOTRY=True
BUG=webrtc:6346
Review-Url: https://codereview.webrtc.org/2437913003
Cr-Commit-Position: refs/heads/master@{#14712}
The AudioMixer is now split in a mixer and audio source interface part, which has moved to webrtc/api, and a default implementation part, which lies in webrtc/modules.
This change makes it possible to create other mixer implementations and is a first step to facilitate passing down a mixer from outside of WebRTC.
It will also create less build dependencies when the new mixer has replaced the old one.
NOTRY=True
TBR=henrik.lundin@webrtc.org
BUG=webrtc:6346
Review-Url: https://codereview.webrtc.org/2411313003
Cr-Commit-Position: refs/heads/master@{#14705}
Changed mixability status into AddSource/RemoveSource. Added 'ssrc()'
method to the MixerSource interface. Removed unnecessary member 'num_audio_sources_' and made the mixer be refcounted.
BUG=webrtc:6346
NOTRY=True
Review-Url: https://codereview.webrtc.org/2408683002
Cr-Commit-Position: refs/heads/master@{#14612}
MixerAudioSource is moved to AudioMixerImpl::Source. Structures and methods of the MixerAudioSource interface have been renamed. The RemixFrame method has added checks and is moved to audio_frame_manipulator.h
BUG=webrtc:6346
Review-Url: https://codereview.webrtc.org/2396803004
Cr-Commit-Position: refs/heads/master@{#14600}
Reason for revert:
breaks chromium FYI
Original issue's description:
> Made MixerAudioSource a pure interface.
>
> This required quite a few small changes in the mixing algorithm
> structure, the mixer interface and the mixer unit tests.
>
> BUG=webrtc:6346
>
> Committed: https://crrev.com/2ae5fdff86b784545cbd724de54bb5ffedde1adf
> Cr-Commit-Position: refs/heads/master@{#14567}
TBR=ivoc@webrtc.org,solenberg@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=webrtc:6346
Review-Url: https://codereview.webrtc.org/2394253003
Cr-Commit-Position: refs/heads/master@{#14568}
This required quite a few small changes in the mixing algorithm
structure, the mixer interface and the mixer unit tests.
BUG=webrtc:6346
Review-Url: https://codereview.webrtc.org/2396483002
Cr-Commit-Position: refs/heads/master@{#14567}
This CL deletes the old and not used video defines in
engine_configurations.h and pre-pends voice_ to indicate there are only
voice/audio defines left in the file.
BUG=none
R=solenberg@webrtc.org
Review URL: https://codereview.webrtc.org/2401673002 .
Cr-Commit-Position: refs/heads/master@{#14558}
1. Use of const in all variable declarations where it is possible
2. Variable names and function arguments changed from CamelCase to match code style
3. A few stale comments removed.
4. Chromium clang plugin check added (now possible thanks to kwiberg@'s work on common.h)
5. Disallow constructor macros added.
NOTRY=true
Review-Url: https://codereview.webrtc.org/2294263002
Cr-Commit-Position: refs/heads/master@{#14120}
Methods are named more consistently and have a more consistent
signatures. The call structure of mixing is slightly
simplified. Anonymous participants are also ramped up.
NOTRY=True
Review-Url: https://codereview.webrtc.org/2298163002
Cr-Commit-Position: refs/heads/master@{#14110}
Removed the OutputMixer part of the new mixer and renamed the new
mixer from NewAudioConferenceMixer to AudioMixer.
NOTRY=True
Review-Url: https://codereview.webrtc.org/2249213005
Cr-Commit-Position: refs/heads/master@{#13883}
