esp32s3聊天机器人（二）

继续上文，硬件软件准备齐全，介绍一下主要用到的库

sherpa-onnx

开源的，语音转文本、文本转语音、说话人分类和 VAD，关键是支持C#开发

OllamaSharp

用于连接ollama，如其名C#开发

虽然离可玩还有一段距离，但是还是要说一下目前遇到的一些问题

1、最初使用流式语音识别，但录音流发送到server之后，完全识别不到文字，保存为pcm播放发现完全是噪音，最后转换放大了音频可以正确识别到说话内容了

static float gain = 5.0f;
short[] int16Array;
float[] floatArray;
public void Recognize(byte[] bytes)
{//Console.WriteLine("收到音频长度："+ bytes.Length);int16Array = new short[bytes.Length / 2];Buffer.BlockCopy(bytes, 0, int16Array, 0, bytes.Length);floatArray = new float[int16Array.Length];for (int i = 0; i < int16Array.Length; i++){floatArray[i] = int16Array[i] / 32768.0f * gain;}onlineStream.AcceptWaveform(sampleRate, floatArray);
}

2、流式识别有个问题，我说下一句话的时候才会确定上一句结束，虽然有三个参数可调，但我多次测试，没调好，只好改用离线识别，给esp32s3添加个按键，按下开始发送录音数据，松开停止发送并告知录音结束，server端再开始识别

            //默认值config.Rule1MinTrailingSilence = 2.4f;config.Rule2MinTrailingSilence = 0.5f;//限制最长说话10秒config.Rule3MinUtteranceLength = 10f;

void loop() {webSocket.loop(); // 必须调用以处理WebSocket事件 if(digitalRead(PIN_BUTTON) == LOW){pressed = true;uint8_t buffer[BUFFER_SIZE];size_t bytesRead;// 从I2S读取音频数据i2s_read(I2S_NUM_0, buffer, BUFFER_SIZE, &bytesRead, portMAX_DELAY);// 通过WebSocket发送音频数据if (webSocket.sendBIN(buffer, bytesRead)) {//Serial.printf("Sent %d bytes of audio data\n", bytesRead); } else {//Serial.println("Failed to send audio data");}}else{if(pressed){ pressed = false;if (webSocket.sendTXT("{\"code\":1,\"message\":\"结束语音\"}")) {} else {}}}
}

        private static void OnMessage(IWebSocketConnection connection, string msg){BaseMsg baseMsg = null;try{baseMsg = JsonConvert.DeserializeObject<BaseMsg>(msg);}catch (Exception e){Console.WriteLine(e);}if (baseMsg != null){// 收到code 1时，结束录音开始识别if (baseMsg.code == 1){Asr asr = null;asrs.TryGetValue(connection.GetHashCode(), out asr);if (asr != null){asr.EndReceive();}}}}

3、周围人多声音嘈杂的时候，语音识别开始放飞自我，七八米开外的人声它都收进来…… 用RNNoise.Net处理了一下，也不知道对不对，感觉有点效果……

https://github.com/Yellow-Dog-Man/RNNoise.Net

        /// <summary>/// 识别语音数据/// </summary>short[] int16Array;float[] floatArray;private void Recognize(byte[] bytes){int16Array = new short[bytes.Length / 2];Buffer.BlockCopy(bytes, 0, int16Array, 0, bytes.Length);floatArray = new float[int16Array.Length];for (int i = 0; i < int16Array.Length; i++){floatArray[i] = int16Array[i] / 32768.0f;}// 降噪using (var denoiser = new Denoiser()){int count = denoiser.Denoise(floatArray.AsSpan());Console.WriteLine("denoised count:" + count);}offlineStream = recognizer.CreateStream();offlineStream.AcceptWaveform(sampleRate, floatArray);recognizer.Decode(offlineStream);string result = offlineStream.Result.Text;offlineStream.Dispose();Console.WriteLine("result:" + result);if (!string.IsNullOrWhiteSpace(result)){result = offlinePunctuation.AddPunct(result.ToLower());BaseMsg textMsg = new BaseMsg(1, result);client.Send(JsonConvert.SerializeObject(textMsg));if (llm != null){llm.RequestAsync(result);}}}