Directory for listing supported audio types

Audio Manager
Any app
Note: Each audio type is represented by one PPS object, which is named after the type.


The Audio Manager publishes the status of each audio type for concurrent audio playback to the /pps/services/audio/types/ directory. By monitoring these objects, an application can take certain actions when an event occurs. For example, a multimedia application may decide to pause when it's being muted by a higher-priority audio source.

Supported audio types

Audio type Description
alarm Used for an alarm, such as a clock alarm.
alert Notifiers, such as calendar events, email, and SMS.
cmas Used for Commercial Mobile Alert System (CMAS) emergency broadcast systems.
default Any unclassified audio stream.
inputfeedback Used for keyboard clicks.
multimedia Used by media player applications.
pushtotalk Used to denote streams related to push-to-talk use cases.
reserved_0 Placeholder value; unused.
ringtone Used for playback of ringtones when an incoming phone call occurs.
soundeffect Sound effects that can never be attenuated, such as the camera click.
texttospeech Text-to-speech services.
videochat Used by the video chat client, this type isn't covered by the voice type because of a difference in automatic routing policy.
voice Voiceband-related streams and certain telephony items (cellular or VoIP).
voicerecognition Voice-recognition services such as Voice-Activated Dialing (VAD).
voicerecording Used for voice-recording services.
voicetones Dual-tone multi-frequency signaling (DTMF) and call-progress tones, but can also be used to play back non-tone-based audio during phone calls.

Audio type attributes

Each audio type object has the following attributes:

Attribute Data type Description
active_pid (deprecated) String

Process ID of the currently playing application.

Note that this is used only with the multimedia type.

attenuated Boolean Indicates whether the audio type is being attenuated.
muted Boolean Indicates whether the audio type is being muted.
muted_by_pid String Process ID of the application that is muting this audio type.