publish_wave.py

import asyncio
import logging
from signal import SIGINT, SIGTERM
import os

import numpy as np
from livekit import rtc, api

SAMPLE_RATE = 48000
NUM_CHANNELS = 1

# ensure LIVEKIT_URL, LIVEKIT_API_KEY, and LIVEKIT_API_SECRET are set


async def main(room: rtc.Room) -> None:
    @room.on("participant_disconnected")
    def on_participant_disconnect(participant: rtc.Participant, *_):
        logging.info("participant disconnected: %s", participant.identity)

    token = (
        api.AccessToken()
        .with_identity("python-publisher")
        .with_name("Python Publisher")
        .with_grants(
            api.VideoGrants(
                room_join=True,
                room="my-room",
            )
        )
        .to_jwt()
    )
    url = os.getenv("LIVEKIT_URL")

    logging.info("connecting to %s", url)
    try:
        await room.connect(
            url,
            token,
            options=rtc.RoomOptions(
                auto_subscribe=True,
            ),
        )
        logging.info("connected to room %s", room.name)
    except rtc.ConnectError as e:
        logging.error("failed to connect to the room: %s", e)
        return

    # publish a track
    source = rtc.AudioSource(SAMPLE_RATE, NUM_CHANNELS)
    track = rtc.LocalAudioTrack.create_audio_track("sinewave", source)
    options = rtc.TrackPublishOptions()
    options.source = rtc.TrackSource.SOURCE_MICROPHONE
    publication = await room.local_participant.publish_track(track, options)
    logging.info("published track %s", publication.sid)

    asyncio.ensure_future(publish_frames(source, 440))


async def publish_frames(source: rtc.AudioSource, frequency: int):
    amplitude = 32767  # for 16-bit audio
    samples_per_channel = 480  # 10ms at 48kHz
    time = np.arange(samples_per_channel) / SAMPLE_RATE
    total_samples = 0
    audio_frame = rtc.AudioFrame.create(SAMPLE_RATE, NUM_CHANNELS, samples_per_channel)
    audio_data = np.frombuffer(audio_frame.data, dtype=np.int16)
    while True:
        time = (total_samples + np.arange(samples_per_channel)) / SAMPLE_RATE
        sine_wave = (amplitude * np.sin(2 * np.pi * frequency * time)).astype(np.int16)
        np.copyto(audio_data, sine_wave)
        await source.capture_frame(audio_frame)
        total_samples += samples_per_channel


if __name__ == "__main__":
    logging.basicConfig(
        level=logging.INFO,
        handlers=[logging.FileHandler("publish_wave.log"), logging.StreamHandler()],
    )

    loop = asyncio.get_event_loop()
    room = rtc.Room(loop=loop)

    async def cleanup():
        await room.disconnect()
        loop.stop()

    asyncio.ensure_future(main(room))
    for signal in [SIGINT, SIGTERM]:
        loop.add_signal_handler(signal, lambda: asyncio.ensure_future(cleanup()))

    try:
        loop.run_forever()
    finally:
        loop.close()