Add node-addon-api for VAD (#864)

nodejs-addon-examples/.gitignore

@@ -0,0 +1 @@
+crash.log

nodejs-addon-examples/README.md

@@ -38,3 +38,12 @@ node ./test_asr_streaming_transducer.js
 
 node ./test_asr_streaming_transducer_microphone.js
 ```
+
+# VAD
+
+```bash
+wget https://github.com/k2-fsa/sherpa-onnx/releases/download/asr-models/silero_vad.onnx
+
+node ./test_vad_microphone.js
+```
+

nodejs-addon-examples/test_asr_streaming_transducer.js

@@ -36,10 +36,10 @@ console.log('Started')
 let start = performance.now();
 const stream = recognizer.createStream();
 const wave = sherpa_onnx.readWave(waveFilename);
-stream.acceptWaveform(wave.samples, wave.sampleRate);
+stream.acceptWaveform({sampleRate: wave.sampleRate, samples: wave.samples});
 
 const tailPadding = new Float32Array(wave.sampleRate * 0.4);
-stream.acceptWaveform(tailPadding, wave.sampleRate);
+stream.acceptWaveform({samples: tailPadding, sampleRate: wave.sampleRate});
 
 while (recognizer.isReady(stream)) {
   recognizer.decode(stream);

nodejs-addon-examples/test_asr_streaming_transducer_microphone.js

@@ -60,7 +60,8 @@ const display = new sherpa_onnx.Display(50);
 ai.on('data', data => {
   const samples = new Float32Array(data.buffer);
 
-  stream.acceptWaveform(samples, recognizer.config.featConfig.sampleRate);
+  stream.acceptWaveform(
+      {sampleRate: recognizer.config.featConfig.sampleRate, samples: samples});
 
   while (recognizer.isReady(stream)) {
     recognizer.decode(stream);

nodejs-addon-examples/test_vad_microphone.js

@@ -0,0 +1,88 @@
+// Copyright (c)  2023-2024  Xiaomi Corporation (authors: Fangjun Kuang)
+
+const portAudio = require('naudiodon2');
+// console.log(portAudio.getDevices());
+
+const sherpa_onnx = require('sherpa-onnx-node');
+
+function createVad() {
+  // please download silero_vad.onnx from
+  // https://github.com/k2-fsa/sherpa-onnx/releases/download/asr-models/silero_vad.onnx
+  const config = {
+    sileroVad: {
+      model: './silero_vad.onnx',
+      threshold: 0.5,
+      minSpeechDuration: 0.25,
+      minSilenceDuration: 0.5,
+      windowSize: 512,
+    },
+    sampleRate: 16000,
+    debug: true,
+    numThreads: 1,
+  };
+
+  const bufferSizeInSeconds = 60;
+
+  return new sherpa_onnx.Vad(config, bufferSizeInSeconds);
+}
+
+vad = createVad();
+
+const bufferSizeInSeconds = 30;
+const buffer =
+    new sherpa_onnx.CircularBuffer(bufferSizeInSeconds * vad.config.sampleRate);
+
+
+const ai = new portAudio.AudioIO({
+  inOptions: {
+    channelCount: 1,
+    closeOnError: true,  // Close the stream if an audio error is detected, if
+                         // set false then just log the error
+    deviceId: -1,  // Use -1 or omit the deviceId to select the default device
+    sampleFormat: portAudio.SampleFormatFloat32,
+    sampleRate: vad.config.sampleRate,
+  }
+});
+
+let printed = false;
+let index = 0;
+ai.on('data', data => {
+  const windowSize = vad.config.sileroVad.windowSize;
+  buffer.push(new Float32Array(data.buffer));
+  while (buffer.size() > windowSize) {
+    const samples = buffer.get(buffer.head(), windowSize);
+    buffer.pop(windowSize);
+    vad.acceptWaveform(samples)
+    if (vad.isDetected() && !printed) {
+      console.log(`${index}: Detected speech`)
+      printed = true;
+    }
+
+    if (!vad.isDetected()) {
+      printed = false;
+    }
+
+    while (!vad.isEmpty()) {
+      const segment = vad.front();
+      vad.pop();
+      const filename = `${index}-${
+          new Date()
+              .toLocaleTimeString('en-US', {hour12: false})
+              .split(' ')[0]}.wav`;
+      sherpa_onnx.writeWave(
+          filename,
+          {samples: segment.samples, sampleRate: vad.config.sampleRate})
+      const duration = segment.samples.length / vad.config.sampleRate;
+      console.log(`${index} End of speech. Duration: ${duration} seconds`);
+      console.log(`Saved to ${filename}`);
+      index += 1;
+    }
+  }
+});
+
+ai.on('close', () => {
+  console.log('Free resources');
+});
+
+ai.start();
+console.log('Started! Please speak')