webaudio-stream-analyser/index.html at master · sutaking/webaudio-stream-analyser · GitHub

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<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8" />
    <title>Audio Visulizer</title>
	<style type="text/css">
		html, body {
			margin: 0;
			font-family: arial, "Microsoft YaHei";
			background-color: #272822;
			color: #FEFEFE;
		}
		#fileWrapper{
			transition:all 0.5s ease;
		}
		#fileWrapper:hover{
			opacity: 1!important;
		}
		#visualizer_wrapper{
			text-align: center;
		}
		footer{
			position: fixed;
			bottom: 2px;
			color:#aaa;
		}
	</style>
</head>

<body onload='init()'>
	<div id="main-content-container" >
		<button onclick="start()">start</button>
		<button onclick="stop()">stop</button>
		<div id="info"></div>
		<div id="visualizer_wrapper">
			<canvas id='canvas' width="800" height="350"></canvas>
		</div>
	</div>
	<script src="animation.js"></script>
	<script type="script/worker" id="workerCode">

	</script>
    <script>
		const url = 'ws://109.123.120.200:5000';
		let ws, player;

        const init = () => {
			console.log(`[${new Date()}] AudioCapture App Start...`);
			ws = new WebSocket(url);

			// 接收二进制数据，需要配置binaryType
			ws.binaryType = 'arraybuffer';
			player = new StreamAnalyser();
			// 绑定链接open & close 事件
			ws.addEventListener('open', event => (console.log(`[${new Date()}] ws server open sucess!`)));
			ws.addEventListener('close', event => (console.log(`[${new Date()}] ws server closed!`)));

			ws.addEventListener('message', event => {
				let raw = new Uint8Array(event.data);
				player.feed(raw);
			});

        }
		let _status;
		const start = () => {
			ws.send('start');
			_status = 1;
			setTimeout(() => {
				const {channels, sampleRate} = player.getAudioInfo();
				document.getElementById('info').innerHTML = `<div>Num of Channels: ${channels}</div>
															<div>Sample Rate: ${sampleRate}</div>`;
			}, 1000);

			// draw canvas animation
			drawSpectrum();
		}

		const stop = () => {
			_status = 0;
			player.stop();
		}

		let animationId,
			allCapsReachBottom = false,
			canvas = document.getElementById('canvas'),
            cwidth = canvas.width,
            cheight = canvas.height - 2,
            meterWidth = 10, //width of the meters in the spectrum
            gap = 2, //gap between meters
            capHeight = 2,
            capStyle = '#fff',
            meterNum = 800 / (10 + 2), //count of the meters
			capYPositionArray = []; ////store the vertical position of hte caps for the preivous frame

		ctx = canvas.getContext('2d'),
        gradient = ctx.createLinearGradient(0, 0, 0, 300);
        gradient.addColorStop(1, '#0f0');
        gradient.addColorStop(0.5, '#ff0');
		gradient.addColorStop(0, '#f00');

		const drawSpectrum = () => {
			let analyser = player.getAnalyzser();
			let array = new Uint8Array(analyser.frequencyBinCount);
			analyser.getByteFrequencyData(array);

			if (_status === 0) {
				// fix when sounds end the value still not back to zero
				for (let i = array.length - 1; i >= 0; i--) {
					array[i] = 0;
				}
				allCapsReachBottom = true;
				for (let i = capYPositionArray.length - 1; i >= 0; i--) {
					allCapsReachBottom = allCapsReachBottom && (capYPositionArray[i] === 0);
				}
				if (allCapsReachBottom) {
					cancelAnimationFrame(animationId);
					return;
				}
			}

			let step = Math.round(array.length / meterNum);//sample limited data from the total array
			ctx.clearRect(0, 0, cwidth, cheight);
			for (let i = 0; i < meterNum; i++) {
				let value = array[i * step];
				if (capYPositionArray.length < Math.round(meterNum)) {
					capYPositionArray.push(value);
				}
				ctx.fillStyle = capStyle;
				//draw the cap, with transition effect
				if (value < capYPositionArray[i]) {
					ctx.fillRect(i * 12, cheight - (--capYPositionArray[i]), meterWidth, capHeight);
				} else {
					ctx.fillRect(i * 12, cheight - value, meterWidth, capHeight);
					capYPositionArray[i] = value;
				}
				ctx.fillStyle = gradient; // set the fillstyle to gradient for a better look
				ctx.fillRect(i * 12 /*meterWidth+gap*/, cheight - value + capHeight, meterWidth, cheight); // the meter
			}
			animationId = requestAnimationFrame(drawSpectrum);
		}

	</script>
	<script>
		(async () => {

			// new feature detect.
			document.querySelector('main').classList.toggle(
				'supported', ('OffscreenCanvas' in window));


		})();
	</script>
	<script type="text/javascript" src="./dist/wav-stream-analyser.min.js"></script>
</body>
</html>