如何在node.js中創建一個blob用於websocket？

Question

我正在嘗試使用IBM的websocket實現他們的語音到文本服務。目前我無法弄清楚如何通過連接發送.wav文件。我知道我需要把它變成一個blob，但我不知道該怎麼做。的現在，我得到錯誤：

You must pass a Node Buffer object to WebSocketConnec

- 或 -

Could not read a WAV header from a stream of 0 bytes

...取決於我試圖傳遞給服務。應該指出的是，我正確地發送了開始消息並且正在使其進入聆聽狀態。

Answer 1

從v1.0開始（仍然在beta）watson-developer-cloud npm模塊支持websockets。

npm install watson-developer-cloud@1.0.0-beta.2 

認識到自己的wav文件：

var watson = require('watson-developer-cloud'); 
var fs = require('fs'); 

var speech_to_text = watson.speech_to_text({ 
    username: 'INSERT YOUR USERNAME FOR THE SERVICE HERE', 
    password: 'INSERT YOUR PASSWORD FOR THE SERVICE HERE', 
    version: 'v1', 
}); 


// create the stream 
var recognizeStream = speech_to_text.createRecognizeStream({ content_type: 'audio/wav' }); 

// pipe in some audio 
fs.createReadStream('audio-to-recognize.wav').pipe(recognizeStream); 

// and pipe out the transcription 
recognizeStream.pipe(fs.createWriteStream('transcription.txt')); 


// listen for 'data' events for just the final text 
// listen for 'results' events to get the raw JSON with interim results, timings, etc. 

recognizeStream.setEncoding('utf8'); // to get strings instead of Buffers from `data` events 

['data', 'results', 'error', 'connection-close'].forEach(function(eventName) { 
    recognizeStream.on(eventName, console.log.bind(console, eventName + ' event: ')); 
}); 

查看更多例子here。