Commit 439e4ed4 authored Apr 03, 2015 by Ravi Kumar Alamanda Committed by Andy Hung Jun 11, 2015

audiopolicy: use deep buffer output by default for music streams

Default disabled. This is enabled by

adb shell setprop audio.deep_buffer.media 1

Applications that use AudioTrack java interface for audio rendering
defaults to primary output as flags indicated as FLAG_NONE. If the
primary output is low latency output, it results higher power
consumption than deep-buffer path if used.
Make the deep buffer output as default option for music streams if
flags are not specified.

It may also be used for testing audio glitches from heavy CPU
or DRM which may cause issues with the FastMixer.

Bug: 21198655
Bug: 21785618
Change-Id: I909c296ddcf4484b9a877ef1c0230ea58537e06a

parent ca097142

services/audiopolicy/managerdefault/AudioPolicyManager.cpp

+5 −0

Original line number	Diff line number	Diff line
		@@ -789,6 +789,11 @@ audio_io_handle_t AudioPolicyManager::getOutputForDevice(
		// only allow deep buffering for music stream type
		if (stream != AUDIO_STREAM_MUSIC) {
		flags = (audio_output_flags_t)(flags &~AUDIO_OUTPUT_FLAG_DEEP_BUFFER);
		} else if (/* stream == AUDIO_STREAM_MUSIC && */
		flags == AUDIO_OUTPUT_FLAG_NONE &&
		property_get_bool("audio.deep_buffer.media", false /* default_value */)) {
		// use DEEP_BUFFER as default output for music stream type
		flags = (audio_output_flags_t)AUDIO_OUTPUT_FLAG_DEEP_BUFFER;
		}
		if (stream == AUDIO_STREAM_TTS) {
		flags = AUDIO_OUTPUT_FLAG_TTS;