chrome/test/data/webrtc/webaudio.js

   1 /**
   2  * Copyright (c) 2013 The Chromium Authors. All rights reserved.
   3  * Use of this source code is governed by a BSD-style license that can be
   4  * found in the LICENSE file.
   5  */
   6
   7 var gContext = null;
   8
   9 function loadAudioAndAddToPeerConnection(url, peerconnection) {
  10   if (gContext == null)
  11     gContext = new AudioContext();
  12
  13   var inputSink = gContext.createMediaStreamDestination();
  14   peerconnection.addStream(inputSink.stream);
  15
  16   loadAudioBuffer_(url, function(voiceSoundBuffer) {
  17     if (peerconnection.webAudioBufferSource)
  18       throw failTest('Cannot load more than one sound per peerconnection.');
  19
  20     peerconnection.webAudioBufferSource = gContext.createBufferSource();
  21     peerconnection.webAudioBufferSource.buffer = voiceSoundBuffer;
  22     peerconnection.webAudioBufferSource.connect(inputSink);
  23     returnToTest('ok-added');
  24   });
  25 }
  26
  27 function playPreviouslyLoadedAudioFile(peerconnection) {
  28   if (!peerconnection.webAudioBufferSource)
  29     throw failTest('Must call loadAudioAndAddToPeerConnection before this.');
  30   peerconnection.webAudioBufferSource.start(gContext.currentTime);
  31 }
  32
  33 /** @private */
  34 function loadAudioBuffer_(url, callback) {
  35   var request = new XMLHttpRequest();
  36   request.open('GET', url, true);
  37   request.responseType = 'arraybuffer';
  38
  39   request.onload = function() {
  40     gContext.decodeAudioData(request.response, function (decodedAudio) {
  41           voiceSoundBuffer = decodedAudio;
  42           callback(voiceSoundBuffer);
  43         });
  44   }
  45   request.send();
  46 }