javascript - 用 arrayBuffer 录制 mp3

问题描述

我用 Stackoverflow 尝试了很多东西，但我无法得到它。所以我尝试用 nodejs (1) 从树莓派录制音频。在此流通过 websocket 服务器之后（我没有放置此代码，因为它只是一个重定向）。最后一个 vuejs 中的 websocket 监听流。在我想用 mp3 (2) 录制这个流之后。但我有噪音或什么都没有。1 - 树莓派：

ai = new audio.AudioIO({
        inOptions: {
          channelCount: 1,
          sampleFormat: audio.SampleFormat16Bit,
          sampleRate: 44100,
          deviceId: 6, // Use -1 or omit the deviceId to select the default device
          closeOnError: true // Close the stream if an audio error is detected, if set false then just log the error
        }
      });

      ai.on('data', buf => {
      
      clientAudioWebsocket.send(buf)
      }
      );
      
     
      ai.start();

2-部分vuejs

插座：

 this.dataBuffer = []

   var self = this

   var connectionToLocalServer = new WebSocket("ws://"+ip  +":4444")
   connectionToLocalServer.binaryType = "arraybuffer"

    connectionToLocalServer.onmessage = function(event) {
        self.dataBuffer.push(event.data);

    }
    connectionToLocalServer.onopen = function(event) {


  }

部分 arraybuffer 到 mp3

  concatArrayBuffers (bufs) {
                          var offset = 0;
                          var bytes = 0;
                          var bufs2=bufs.map(function(buf,total){
                              bytes += buf.byteLength;
                              return buf;
                          });
                          var buffer = new ArrayBuffer(bytes);
                          var store = new Uint8Array(buffer);
                          bufs2.forEach(function(buf){
                              store.set(new Uint8Array(buf.buffer||buf,buf.byteOffset),offset);
                              offset += buf.byteLength;
                          });
                          return buffer }



          this.tmpResult = this.concatArrayBuffers(this.dataBuffer);

          var mp3Data = [];

          var mp3encoder = new lamejs.Mp3Encoder(1, 44100, 128);

          var mp3Tmp = mp3encoder.encodeBuffer(this.tmpResult, 0, Math.floor(this.tmpResult.byteLength / 2)); 
        //Push encode buffer to mp3Data variable
          mp3Data.push(mp3Tmp);

          // Get end part of mp3
          mp3Tmp = mp3encoder.flush();

          // Write last data to the output data, too
          // mp3Data contains now the complete mp3Data
          mp3Data.push(mp3Tmp);

而且我不明白为什么我有 16384 大小的缓冲区的数组缓冲区。我真的对任何解决方案持开放态度，但我不想在服务器端这样做。谢谢

标签： javascriptnode.jsvue.jsaudiowebsocket

所以我找到了解决方案，这是因为我没有创建一个 Int16Array :-( （有时最好在 1 小时之外，然后你会找到解决方案）

解决方案是：

let tmpResult = this.concatArrayBuffers(this.dataBuffer)
     
var samples = new Int16Array(tmpResult);
var buffer = [];
var mp3enc = new lamejs.Mp3Encoder(1, 44100, 128);
var remaining = samples.length;
var maxSamples = 1152;
for (var i = 0; remaining >= maxSamples; i += maxSamples) {
     var mono = samples.subarray(i, i + maxSamples);
     var mp3buf = mp3enc.encodeBuffer(mono);
     if (mp3buf.length > 0) {
         buffer.push(new Int8Array(mp3buf));
        }
        remaining -= maxSamples;
}
var d = mp3enc.flush();
if(d.length > 0){
 buffer.push(new Int8Array(d));
}

console.log('done encoding, size=', buffer.length);
var blob = new Blob(buffer, {type: 'audio/mp3'});

javascript - 用 arrayBuffer 录制 mp3

问题描述

解决方案

推荐阅读