分析器条形动画 HTML 音频 API 不工作

Question

我使用音频 api 的 js 代码来可视化我的 html5 音频，它在 tutorial/code

中效果很好

link: https://www.developphp.com/video/Jav...o-API-Tutorial

它工作得很好，但是当我用外部 link 更改 src 时出现问题，例如：

音频不发声，可视化不显示，虽然当我删除可视化代码时它正常工作...我尝试更改

context.createMediaElementSource(audio);

和

AudioContext.createMediaStreamDestination()

音频播放但仍然没有可视化..我不知道我能做些什么？

<!doctype html>
<html>
<head>
<meta charset="utf-8"/>
<meta http-equiv="Access-Control-Allow-Origin" content="*">
<style>
div#mp3_player{ width:500px; height:60px; background:#000; padding:5px; margin:50px auto; }
div#mp3_player > div > audio{  width:500px; background:#000; float:left;  }
div#mp3_player > canvas{ width:500px; height:30px; background:#002D3C; float:left; }
</style>
<script>
// Create a new instance of an audio object and adjust some of its properties
var audio = new Audio();
// audio.crossOrigin='anonymous';
audio.src = 'http://www.stephaniequinn.com/Music/Allegro%20from%20Duet%20in%20C%20Major.mp3';
audio.controls = true;
audio.loop = true;
audio.autoplay = true;
// Establish all variables that your Analyser will use
var canvas, ctx, source, context, analyser, fbc_array, bars, bar_x, bar_width, bar_height;
// Initialize the MP3 player after the page loads all of its HTML into the window
window.addEventListener("load", initMp3Player, false);
function initMp3Player(){
 document.getElementById('audio_box').appendChild(audio);
 context = new AudioContext(); // AudioContext object instance
 analyser = context.createAnalyser(); // AnalyserNode method
 canvas = document.getElementById('analyser_render');
 ctx = canvas.getContext('2d');
 // Re-route audio playback into the processing graph of the AudioContext
 
 source = context.createMediaStreamDestination(audio); 
 
 source.connect(analyser);
 analyser.connect(context.destination);
 frameLooper();

// frameLooper() animates any style of graphics you wish to the audio frequency
// Looping at the default frame rate that the browser provides(approx. 60 FPS)
function frameLooper(){
 window.requestAnimationFrame(frameLooper);
 fbc_array = new Uint8Array(analyser.frequencyBinCount);
 analyser.getByteFrequencyData(fbc_array);
 ctx.clearRect(0, 0, canvas.width, canvas.height); // Clear the canvas
 ctx.fillStyle = '#00CCFF'; // Color of the bars
 bars = 100;
 for (var i = 0; i < bars; i++) {
  bar_x = i * 3;
  bar_width = 2;
  bar_height = -(fbc_array[i] / 2);
  //  fillRect( x, y, width, height ) // Explanation of the parameters below
  ctx.fillRect(bar_x, canvas.height, bar_width, bar_height);
 }
}
}

</script>
</head>
<body>
<div id="mp3_player">
  <div id="audio_box"></div>
  <canvas id="analyser_render"></canvas>
</div>
</body>
</html>

Answer 1

问题可能出在分析器节点上。它只能处理按照 CORS.

加载的媒体

如果为您的媒体提供服务的服务器是 well configured，您可以尝试设置音频元素的 crossOrigin 属性，否则，您将不得不从您自己的域提供文件。

分析器条形动画 HTML 音频 API 不工作

Analyser Bars Animation HTML Audio API not working

html

javascript

audio

html5-canvas

audiocontext