问题描述
我使用本教程: http://typedarray.org/from-microphone-to-wav-with-getusermedia-and-web-audio/
和此实时演示页面: http://typedarray.org/wp-content/projects/WebAudioRecorder/
创建我的高频分析仪.
我的问题是,默认情况下,Web Audio API会切断高频.
My problem is that Web Audio API, i thing, by default cut off high frequencies.
当我录制WAV并播放10000hz信号时,wav包含我的频率.
When i record WAV and play 10000hz signal, wav contain my freq.
如果我播放17000hz信号,WAV将不包含我的频率.
If i play 17000hz signal, wav don't contain my freq.
如何禁用低通滤波器?
代码:
function success(e){
// creates the audio context
audioContext = window.AudioContext || window.webkitAudioContext;
context = new audioContext();
// creates a gain node
volume = context.createGain();
// creates an audio node from the microphone incoming stream
audioInput = context.createMediaStreamSource(e);
// connect the stream to the gain node
audioInput.connect(volume);
/* From the spec: This value controls how frequently the audioprocess event is
dispatched and how many sample-frames need to be processed each call.
Lower values for buffer size will result in a lower (better) latency.
Higher values will be necessary to avoid audio breakup and glitches */
var bufferSize = 2048;
recorder = context.createJavaScriptNode(bufferSize, 2, 2);
recorder.onaudioprocess = function(e){
console.log ('recording');
var left = e.inputBuffer.getChannelData (0);
var right = e.inputBuffer.getChannelData (1);
// we clone the samples
leftchannel.push (new Float32Array (left));
rightchannel.push (new Float32Array (right));
recordingLength += bufferSize;
}
// we connect the recorder
volume.connect (recorder);
recorder.connect (context.destination);
}
推荐答案
这是在 getUserMedia
中,而不是Web Audio API中.默认情况下, getUserMedia
为您提供的 MediaStream
包含已包含的数据(取决于浏览器):-回声已取消-抑制了噪音-已应用自动增益补偿
This is in getUserMedia
and not the Web Audio API. By default, the MediaStream
that getUserMedia
gives you contains data that has been (depending on the browser):- echo cancelled- had the noise suppressed- had automatic gain compensation applied
您可以使用约束禁用这些约束(例如,对于Firefox):
You can disable those using constraints (for example, for Firefox):
navigator.mediaDevices.getUserMedia({audio:{echoCancellation:假,mozNoiseSuppression:否,mozAutoGainControl:否});
我们目前正在对这些属性进行标准化,但尚未完成.
We are currently standardizing those properties, but we're not done yet.
这篇关于Web音频API-捕获音频-禁用低通滤波器的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持!