H5语音识别功能(Web Speech API+科大讯飞)

H5语音识别效果图:

方案一:Web Speech API(免费,IE浏览器可用,谷歌浏览器不可用)

方案二:科大讯飞(收费,但是每个账号每天500次试用机会)

utils/lat_xunfei/IatRecorder.js

const APPID = "f70c6429";
const API_SECRET = "YjBiOTU2YTU4YzEzZWQ3MWZlNGNkM2I3";
const API_KEY = "beba0ca58e09b5a244858b5d0dab8b8b";
import CryptoJS from "crypto-js";
const transWorker = new Worker(
  new URL("./transcode.worker.js", import.meta.url)
);

console.log("transWorker", transWorker);
var startTime = "";
var endTime = "";

function getWebSocketUrl() {
  return new Promise((resolve, reject) => {
    // 请求地址根据语种不同变化
    var url = "wss://iat-api.xfyun.cn/v2/iat";
    var host = "iat-api.xfyun.cn";
    var apiKey = API_KEY;
    var apiSecret = API_SECRET;
    var date = new Date().toGMTString();
    var algorithm = "hmac-sha256";
    var headers = "host date request-line";
    var signatureOrigin = `host: ${host}\ndate: ${date}\nGET /v2/iat HTTP/1.1`;
    var signatureSha = CryptoJS.HmacSHA256(signatureOrigin, apiSecret);
    var signature = CryptoJS.enc.Base64.stringify(signatureSha);
    var authorizationOrigin = `api_key="${apiKey}", algorithm="${algorithm}", headers="${headers}", signature="${signature}"`;
    var authorization = btoa(authorizationOrigin);
    url = `${url}?authorization=${authorization}&date=${date}&host=${host}`;
    resolve(url);
  });
}
const IatRecorder = class {
  constructor({ language, accent, appId } = {}) {
    let self = this;
    this.status = "null";
    this.language = language || "zh_cn";
    this.accent = accent || "mandarin";
    this.appId = appId || APPID;
    // 记录音频数据
    this.audioData = [];
    // 记录听写结果
    this.resultText = "";
    // wpgs下的听写结果需要中间状态辅助记录
    this.resultTextTemp = "";
    transWorker.onmessage = function (event) {
      // console.log("构造方法中",self.audioData)
      self.audioData.push(...event.data);
    };
  }

  // 修改录音听写状态
  setStatus(status) {
    this.onWillStatusChange &&
      this.status !== status &&
      this.onWillStatusChange(this.status, status);
    this.status = status;
  }
  setResultText({ resultText, resultTextTemp } = {}) {
    this.onTextChange && this.onTextChange(resultTextTemp || resultText || "");
    resultText !== undefined && (this.resultText = resultText);
    resultTextTemp !== undefined && (this.resultTextTemp = resultTextTemp);
  }
  // 修改听写参数
  setParams({ language, accent } = {}) {
    language && (this.language = language);
    accent && (this.accent = accent);
  }
  // 连接websocket
  connectWebSocket() {
    return getWebSocketUrl().then((url) => {
      let iatWS;
      if ("WebSocket" in window) {
        iatWS = new WebSocket(url);
      } else if ("MozWebSocket" in window) {
        iatWS = new MozWebSocket(url);
      } else {
        alert("浏览器不支持WebSocket");
        return;
      }
      this.webSocket = iatWS;
      this.setStatus("init");
      iatWS.onopen = (e) => {
        this.setStatus("ing");
        // 重新开始录音
        setTimeout(() => {
          this.webSocketSend();
        }, 500);
      };
      iatWS.onmessage = (e) => {
        this.result(e.data);
      };
      iatWS.onerror = (e) => {
        this.recorderStop();
      };
      iatWS.onclose = (e) => {
        endTime = Date.parse(new Date());
        console.log("持续时间", endTime - startTime);
        this.recorderStop();
      };
    });
  }
  // 初始化浏览器录音
  recorderInit() {
    navigator.getUserMedia =
      navigator.getUserMedia ||
      navigator.webkitGetUserMedia ||
      navigator.mozGetUserMedia ||
      navigator.msGetUserMedia;

    // 创建音频环境
    try {
      this.audioContext = new (window.AudioContext ||
        window.webkitAudioContext)();
      this.audioContext.resume();
      if (!this.audioContext) {
        alert("浏览器不支持webAudioApi相关接口");
        return;
      }
    } catch (e) {
      if (!this.audioContext) {
        alert("浏览器不支持webAudioApi相关接口");
        return;
      }
    }

    // 获取浏览器录音权限
    if (navigator.mediaDevices && navigator.mediaDevices.getUserMedia) {
      navigator.mediaDevices
        .getUserMedia({
          audio: true,
          video: false,
        })
        .then((stream) => {
          getMediaSuccess(stream);
        })
        .catch((e) => {
          getMediaFail(e);
        });
    } else if (navigator.getUserMedia) {
      navigator.getUserMedia(
        {
          audio: true,
          video: false,
        },
        (stream) => {
          getMediaSuccess(stream);
        },
        function (e) {
          getMediaFail(e);
        }
      );
    } else {
      if (
        navigator.userAgent.toLowerCase().match(/chrome/) &&
        location.origin.indexOf("https://") < 0
      ) {
        alert(
          "chrome下获取浏览器录音功能，因为安全性问题，需要在localhost或127.0.0.1或https下才能获取权限"
        );
      } else {
        alert("无法获取浏览器录音功能，请升级浏览器或使用chrome");
      }
      this.audioContext && this.audioContext.close();
      return;
    }
    // 获取浏览器录音权限成功的回调
    let getMediaSuccess = (stream) => {
      // 创建一个用于通过JavaScript直接处理音频
      this.scriptProcessor = this.audioContext.createScriptProcessor(0, 1, 1);
      this.scriptProcessor.onaudioprocess = (e) => {
        // 去处理音频数据
        if (this.status === "ing") {
          transWorker.postMessage(e.inputBuffer.getChannelData(0));
          //  this.audioData.push(e.inputBuffer.getChannelData(0))
        }
      };
      // 创建一个新的MediaStreamAudioSourceNode 对象，使来自MediaStream的音频可以被播放和操作
      this.mediaSource = this.audioContext.createMediaStreamSource(stream);
      // 连接
      this.mediaSource.connect(this.scriptProcessor);
      this.scriptProcessor.connect(this.audioContext.destination);
      this.connectWebSocket();
    };

    let getMediaFail = (e) => {
      this.audioContext && this.audioContext.close();
      this.audioContext = undefined;
      // 关闭websocket
      if (this.webSocket && this.webSocket.readyState === 1) {
        this.webSocket.close();
      }
    };
  }
  recorderStart() {
    if (!this.audioContext) {
      this.recorderInit();
    } else {
      this.audioContext.resume();
      this.connectWebSocket();
    }
  }
  // 暂停录音
  recorderStop() {
    // safari下suspend后再次resume录音内容将是空白，设置safari下不做suspend
    if (
      !(
        /Safari/.test(navigator.userAgent) && !/Chrome/.test(navigator.userAgen)
      )
    ) {
      this.audioContext && this.audioContext.suspend();
    }
    this.setStatus("end");
  }
  // 处理音频数据
  // transAudioData(audioData) {
  //   audioData = transAudioData.transaction(audioData)
  //   this.audioData.push(...audioData)
  // }
  // 对处理后的音频数据进行base64编码，
  toBase64(buffer) {
    var binary = "";
    var bytes = new Uint8Array(buffer);
    var len = bytes.byteLength;
    for (var i = 0; i < len; i++) {
      binary += String.fromCharCode(bytes[i]);
    }
    return window.btoa(binary);
  }
  // 向webSocket发送数据
  webSocketSend() {
    if (this.webSocket.readyState !== 1) {
      return;
    }
    let audioData = this.audioData.splice(0, 1280);
    var params = {
      common: {
        app_id: this.appId,
      },
      business: {
        language: this.language, //小语种可在控制台--语音听写（流式）--方言/语种处添加试用
        domain: "iat",
        accent: this.accent, //中文方言可在控制台--语音听写（流式）--方言/语种处添加试用
      },
      data: {
        status: 0,
        format: "audio/L16;rate=16000",
        encoding: "raw",
        audio: this.toBase64(audioData),
      },
    };
    console.log("参数language：", this.language);
    console.log("参数accent：", this.accent);
    this.webSocket.send(JSON.stringify(params));
    startTime = Date.parse(new Date());
    this.handlerInterval = setInterval(() => {
      // websocket未连接
      if (this.webSocket.readyState !== 1) {
        console.log("websocket未连接");
        this.audioData = [];
        clearInterval(this.handlerInterval);
        return;
      }
      if (this.audioData.length === 0) {
        console.log("自动关闭", this.status);
        if (this.status === "end") {
          this.webSocket.send(
            JSON.stringify({
              data: {
                status: 2,
                format: "audio/L16;rate=16000",
                encoding: "raw",
                audio: "",
              },
            })
          );
          this.audioData = [];
          clearInterval(this.handlerInterval);
        }
        return false;
      }
      audioData = this.audioData.splice(0, 1280);
      // 中间帧
      this.webSocket.send(
        JSON.stringify({
          data: {
            status: 1,
            format: "audio/L16;rate=16000",
            encoding: "raw",
            audio: this.toBase64(audioData),
          },
        })
      );
    }, 40);
  }
  result(resultData) {
    // 识别结束
    let jsonData = JSON.parse(resultData);
    if (jsonData.data && jsonData.data.result) {
      let data = jsonData.data.result;
      let str = "";
      let resultStr = "";
      let ws = data.ws;
      for (let i = 0; i < ws.length; i++) {
        str = str + ws[i].cw[0].w;
      }
      console.log("识别的结果为：", str);
      // 开启wpgs会有此字段(前提：在控制台开通动态修正功能)
      // 取值为 "apd"时表示该片结果是追加到前面的最终结果；取值为"rpl" 时表示替换前面的部分结果，替换范围为rg字段
      if (data.pgs) {
        if (data.pgs === "apd") {
          // 将resultTextTemp同步给resultText
          this.setResultText({
            resultText: this.resultTextTemp,
          });
        }
        // 将结果存储在resultTextTemp中
        this.setResultText({
          resultTextTemp: this.resultText + str,
        });
      } else {
        this.setResultText({
          resultText: this.resultText + str,
        });
      }
    }
    if (jsonData.code === 0 && jsonData.data.status === 2) {
      this.webSocket.close();
    }
    if (jsonData.code !== 0) {
      this.webSocket.close();
      console.log(`${jsonData.code}:${jsonData.message}`);
    }
  }
  start() {
    this.recorderStart();
    this.setResultText({ resultText: "", resultTextTemp: "" });
  }
  stop() {
    this.recorderStop();
  }
};

export default IatRecorder;