Building a Real-Time Audio/Video Live Streaming Project with WebRTC and Swoole

With the continuous development of internet technologies, audio/video live streaming has become increasingly popular, leading developers to explore related solutions such as WebRTC and Swoole.

1. Setting up the Swoole server – Swoole is an open‑source high‑performance network communication framework for PHP. The following code creates a WebSocket server that listens on port 9501 and handles connection, message, and close events:

$server = new swoole_websocket_server("0.0.0.0", 9501);
$server->on("open", function (swoole_websocket_server $server, $request) {
    echo "client " . $request->fd . " connected
";
});
$server->on("message", function (swoole_websocket_server $server, $frame) {
    echo "received message: " . $frame->data . "
";
    $server->push($frame->fd, "hello");
});
$server->on("close", function (swoole_websocket_server $server, $fd) {
    echo "client {$fd} closed
";
});
$server->start();

Running this script starts the WebSocket server, which will later be used to exchange signaling data for WebRTC.

2. Real‑time audio/video communication with WebRTC – WebRTC provides browser‑to‑browser media streaming. The example below requests access to the user's camera and microphone and attaches the stream to a video element:

navigator.getUserMedia({audio: true, video: true}, function(stream) {
    var video = document.querySelector('video');
    video.srcObject = stream;
}, function(error) {
    console.error(error);
});

Combined with the Swoole WebSocket server for signaling, this enables real‑time peer‑to‑peer media exchange.

3. Video stream segmentation – To ensure smooth transmission, the media can be sliced into small segments using FFmpeg. The following command creates HLS fragments of five seconds each:

ffmpeg -i input.mp4 -c:v libx264 -c:a aac -f hls -hls_time 5 -hls_list_size 0 output.m3u8

These segments can be sent through the WebSocket connection as they become available, allowing continuous playback on the client side.

4. Complete project code – The article provides the full set of server‑side and client‑side snippets shown above, which together constitute a functional audio/video live‑streaming application built with WebRTC and Swoole.

By following these steps, developers can quickly prototype a live‑streaming service and gain practical experience with both backend (Swoole) and frontend (WebRTC) real‑time communication technologies.