chore: checkpoint 第一版

device-simulator-windows/public/pcm-capture.worklet.js

@@ -0,0 +1,47 @@
+class PCM16CaptureProcessor extends AudioWorkletProcessor {
+  constructor(options) {
+    super();
+    this.targetRate = Number(options.processorOptions?.targetSampleRate || 16000);
+    this.frameSamples = Number(options.processorOptions?.frameSamples || 320);
+    this.ratio = sampleRate / this.targetRate;
+    this.source = [];
+    this.position = 0;
+    this.output = [];
+  }
+
+  process(inputs) {
+    const channel = inputs[0]?.[0];
+    if (!channel?.length) return true;
+    for (const sample of channel) this.source.push(sample);
+    while (this.position + this.ratio <= this.source.length) {
+      const start = Math.floor(this.position);
+      const end = Math.max(start + 1, Math.floor(this.position + this.ratio));
+      let sum = 0;
+      for (let index = start; index < end && index < this.source.length; index += 1) sum += this.source[index];
+      this.output.push(sum / Math.max(1, end - start));
+      this.position += this.ratio;
+      if (this.output.length >= this.frameSamples) this.flush();
+    }
+    const consumed = Math.floor(this.position);
+    if (consumed > 0) {
+      this.source.splice(0, consumed);
+      this.position -= consumed;
+    }
+    return true;
+  }
+
+  flush() {
+    const frame = this.output.splice(0, this.frameSamples);
+    const pcm = new Int16Array(frame.length);
+    let energy = 0;
+    for (let index = 0; index < frame.length; index += 1) {
+      const sample = Math.max(-1, Math.min(1, frame[index]));
+      energy += sample * sample;
+      pcm[index] = sample < 0 ? Math.round(sample * 32768) : Math.round(sample * 32767);
+    }
+    const volume = Math.min(100, Math.round(Math.sqrt(energy / Math.max(1, frame.length)) * 280));
+    this.port.postMessage({ type: "pcm", bytes: pcm.buffer, volume }, [pcm.buffer]);
+  }
+}
+
+registerProcessor("pcm16-capture", PCM16CaptureProcessor);