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

With the rise of internet technologies, audio/video live streaming has become popular, and related technologies such as WebRTC and Swoole attract developers. This article shows how to build a practical live streaming project using these two technologies.

1. Set up a Swoole server

Swoole is a high‑performance network communication framework for PHP. After installing the Swoole extension, we create a WebSocket server as follows:

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

Running this code starts the WebSocket server, which will be used together with WebRTC for real‑time communication.

2. WebRTC real‑time audio/video communication

WebRTC enables peer‑to‑peer audio/video streams directly in browsers. Using a STUN/TURN server for NAT traversal, we capture the user's media with the following JavaScript:

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

This code obtains the media stream and attaches it to a video element, which can then be sent through the previously created WebSocket server.

3. Real‑time video segmenting

To ensure smooth transmission, the video stream is split into small segments using FFmpeg:

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

The segmented files can be pushed to clients via the WebSocket connection.

Finally, the article provides the complete code for the Swoole server, the WebRTC client, and the FFmpeg command, enabling readers to build their own audio/video live streaming application.