Sound Instruction

A Sound Instruction describes what audio to play. Its in JSON format for network, file and other APIs. The following are the available instructions and their JSON encoding:

Play a file

A plain string is a path to an audio file, the directory the path is relative to is determined by the context (e.g. directory containing the WASM file for wasm activities, "activities/user/" for WebSocket activities) An absolute path (starting with /) is always relative to the root activities directory regardless of context.

"my_activity/beep.wav"

List (sequential)

An array plays sounds one after the other.

["my_activity/intro.wav", "my_activity/loop.wav"]

Simultaneous

Plays multiple sounds at the same time.

{"i": "simultaneous", "sounds": ["my_activity/drums.wav", "my_activity/melody.wav"]}

Repeat

Repeats a sound. Omit times to loop forever.

{"i": "repeat", "sound": "my_activity/tick.wav", "times": 4}

Silence

Inserts a pause.

{"i": "silence", "millis": 1500}

Speak number

Speaks a number aloud using the built-in voice.

{"i": "speak_number", "number": 42}

Error sound

Plays the system error sound (a beep).

{"i": "error_sound"}

Empty sound

A no-op sound that finishes immediately.

{"i": "empty_sound"}