Index: media/renderers/audio_renderer_impl.cc |
diff --git a/media/renderers/audio_renderer_impl.cc b/media/renderers/audio_renderer_impl.cc |
index bddab5c0b7f939387bdebd6f277a04062d83e2bd..95f5c5cfca4d0bd10162695dbb564d584a219e9c 100644 |
--- a/media/renderers/audio_renderer_impl.cc |
+++ b/media/renderers/audio_renderer_impl.cc |
@@ -44,6 +44,7 @@ AudioRendererImpl::AudioRendererImpl( |
media_log_(media_log), |
tick_clock_(new base::DefaultTickClock()), |
last_audio_memory_usage_(0), |
+ last_decoded_sample_rate_(0), |
playback_rate_(0.0), |
state_(kUninitialized), |
buffering_state_(BUFFERING_HAVE_NOTHING), |
@@ -369,15 +370,42 @@ void AudioRendererImpl::Initialize( |
} |
#endif |
- audio_parameters_.Reset( |
- hw_params.format(), |
- // Always use the source's channel layout to avoid premature downmixing |
- // (http://crbug.com/379288), platform specific issues around channel |
- // layouts (http://crbug.com/266674), and unnecessary upmixing overhead. |
- stream->audio_decoder_config().channel_layout(), sample_rate, |
- hw_params.bits_per_sample(), |
- AudioHardwareConfig::GetHighLatencyBufferSize(sample_rate, |
- preferred_buffer_size)); |
+ int stream_channel_count = ChannelLayoutToChannelCount( |
+ stream->audio_decoder_config().channel_layout()); |
+ |
+ // We don't know how to up-mix for DISCRETE layouts (fancy multichannel |
+ // hardware with non-standard speaker arrangement). Instead, pretend the |
+ // hardware layout is 5.1 and let the OS take care of further up-mixing to |
+ // the discrete layout. (http://crbug.com/266674) |
+ ChannelLayout hw_channel_layout = |
+ (hw_params.channel_layout() == CHANNEL_LAYOUT_DISCRETE) |
DaleCurtis
2016/03/25 21:57:00
Remove unnecessary parens. Upon further considerat
chcunningham
2016/03/25 23:52:17
Done.
|
+ ? CHANNEL_LAYOUT_5_1 |
+ : hw_params.channel_layout(); |
+ int hw_channel_count = ChannelLayoutToChannelCount(hw_channel_layout); |
+ |
+ // The layout we pass to |audio_parameters_| will be used for the lifetime |
+ // of this audio renderer, regardless of changes to hardware and/or stream |
+ // properties. Below we choose the max of stream layout vs. hardware layout |
+ // to leave room for changes to the hardware and/or stream (i.e. avoid |
+ // premature down-mixing - http://crbug.com/379288). |
+ // If stream_channels < hw_channels: |
+ // Taking max means we up-mix to hardware layout. If stream later changes |
+ // to have more channels, we aren't locked into down-mixing to the |
+ // initial stream layout. |
+ // If stream_channels > hw_channels: |
+ // We choose to output stream's layout, meaning mixing is a no-op for the |
+ // renderer. Browser-side will down-mix to the hardware config. If the |
+ // hardware later changes to equal stream channels, browser-side will stop |
+ // down-mixing and use the data from all stream channels. |
+ ChannelLayout renderer_channel_layout = |
+ (hw_channel_count > stream_channel_count) |
+ ? hw_channel_layout |
+ : stream->audio_decoder_config().channel_layout(); |
+ |
+ audio_parameters_.Reset(hw_params.format(), renderer_channel_layout, |
+ sample_rate, hw_params.bits_per_sample(), |
+ AudioHardwareConfig::GetHighLatencyBufferSize( |
+ sample_rate, preferred_buffer_size)); |
} |
audio_clock_.reset( |
@@ -472,6 +500,15 @@ void AudioRendererImpl::DecodedAudioReady( |
} |
if (expecting_config_changes_) { |
+ if (buffer->sample_rate() != last_decoded_sample_rate_) { |
+ DVLOG(1) << __FUNCTION__ << " Updating audio sample_rate." |
+ << " ts:" << buffer->timestamp().InMicroseconds() |
+ << " old:" << last_decoded_sample_rate_ |
+ << " new:" << buffer->sample_rate(); |
+ OnConfigChange(); |
+ } |
+ last_decoded_sample_rate_ = buffer->sample_rate(); |
+ |
DCHECK(buffer_converter_); |
buffer_converter_->AddInput(buffer); |
while (buffer_converter_->HasNextBuffer()) { |