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該代碼應該流式傳輸任何網址並提供音頻的可視化。不幸的是，可視化工具不起作用。可視化依賴於來自AnalyzerNode的數據，該數據總是返回空數據。爲什麼這個代碼中的AnalyserNode沒有工作？ I .connect（）後，源節點上的numberOfOutputs增加，但AnalyserNode上的numberOfInputs不變。JavaScript網絡音頻API分析器節點不工作
<html>
<head>
<script>
var context;
var source;
var analyser;
var canvas;
var canvasContext;
window.addEventListener('load', init, false);
function init() {
try {
// Fix up for prefixing
window.AudioContext = window.AudioContext || window.webkitAudioContext;
window.requestAnimationFrame = window.requestAnimationFrame || window.mozRequestAnimationFrame ||
window.webkitRequestAnimationFrame || window.msRequestAnimationFrame;
context = new AudioContext();
analyser = context.createAnalyser();
canvas = document.getElementById("analyser");
canvasContext = canvas.getContext('2d');
}
catch(e) {
alert(e);
alert('Web Audio API is not supported in this browser');
}
}
function streamSound(url) {
var audio = new Audio();
audio.src = url;
audio.controls = true;
audio.autoplay = true;
source = context.createMediaElementSource(audio);
source.connect(analyser);
analyser.connect(context.destination);
document.body.appendChild(document.createElement('br'));
document.body.appendChild(audio);
render();
}
function render(){
window.requestAnimationFrame(render);
//Get the Sound data
var freqByteData = new Uint8Array(analyser.frequencyBinCount);
analyser.getByteFrequencyData(freqByteData);
//we Clear the Canvas
canvasContext.clearRect(0, 0, canvas.width, canvas.height);
//draw visualization
for(var i=0;i<analyser.frequencyBinCount;i++){
canvasContext.fillRect(i*2,canvas.height,1,-freqByteData[i]);
//Data seems to always be zero
if(freqByteData[i] != 0) {
alert(freqByteData[i]);
}
}
}
</script>
</head>
<body>
<button onclick="streamSound(document.getElementById('url').value)"> Stream sound</button>
<input id="url" size='77' value="Enter a URL to Stream">
<br />
<canvas id="analyser" width="600" height="200"></canvas>
</body>
</html>
非常感謝。修復！ – user2392226