Voice testing

src/lib/audio.ts

@@ -0,0 +1,47 @@
+async function getMicStream() {
+  return await navigator.mediaDevices.getUserMedia({
+    audio: {
+      echoCancellation: true,
+      noiseSuppression: true,
+      autoGainControl: true,
+    },
+  });
+}
+
+export async function startMic(onAudio: (data: Int16Array) => void) {
+  const stream = await getMicStream();
+
+  const audioCtx = new AudioContext({ sampleRate: 48000 });
+  await audioCtx.audioWorklet.addModule("/audio-worklet.js");
+
+  const source = audioCtx.createMediaStreamSource(stream);
+  const worklet = new AudioWorkletNode(audioCtx, "mic-processor");
+
+  source.connect(worklet);
+  worklet.connect(audioCtx.destination); // optional
+
+  worklet.port.onmessage = (e) => {
+    const float32 = e.data as Float32Array;
+    const pcm16 = float32ToPCM16(float32);
+    onAudio(pcm16);
+  };
+}
+
+function float32ToPCM16(float32: Float32Array): Int16Array {
+  const pcm16 = new Int16Array(float32.length);
+  for (let i = 0; i < float32.length; i++) {
+    const s = Math.max(-1, Math.min(1, float32[i]));
+    pcm16[i] = s < 0 ? s * 0x8000 : s * 0x7fff;
+  }
+  return pcm16;
+}
+
+export function sendVoice(ws: WebSocket, voiceId: number, pcm: Int16Array) {
+  const buffer = new ArrayBuffer(2 + pcm.byteLength);
+  const view = new DataView(buffer);
+
+  view.setUint16(0, voiceId, true); // little endian
+  new Uint8Array(buffer, 2).set(new Uint8Array(pcm.buffer));
+
+  ws.send(buffer);
+}