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@fstanis
Last active March 7, 2023 01:42
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Demo on creating SVG waveforms from an audio file.
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Copyright 2018 Google LLC
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
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Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
-->
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Audio Visualizer</title>
<style>
body {
margin: 0;
}
#drop {
display: flex;
justify-content: center;
align-items: center;
position: absolute;
top: 0;
width: 100vw;
height: 100vh;
overflow: hidden;
}
</style>
</head>
<body>
<div id="dummy"></div>
<a id="download" href="#" download="waveform.svg" hidden>Download</a>
<div id="drop" ondrop="dropHandler(event)" ondragover="event.preventDefault()">
<div>Drag and drop here!</div>
</div>
<script src="https://unpkg.com/wavesurfer.js"></script>
<script src="https://cdn.jsdelivr.net/gh/gliffy/canvas2svg/canvas2svg.js"></script>
<script>
async function dropHandler(event) {
event.preventDefault();
const items = event.dataTransfer.items;
if (items && items.length >= 1 && items[0].kind === 'file') {
const file = items[0].getAsFile();
triggerDownload(await audioToSvg(file));
}
}
function audioToSvg(file) {
return new Promise(resolve => {
const canvas = new C2S('100%', '100%');
canvas.style = {};
HTMLCanvasElement.prototype.getContext = () => canvas;
const wavesurfer = WaveSurfer.create({
container: '#dummy',
maxCanvasWidth: 100000
});
wavesurfer.on('ready', () => {
canvas.save();
requestIdleCallback(() => resolve(canvas.getSerializedSvg(true)));
});
wavesurfer.loadBlob(file);
});
}
function triggerDownload(svg) {
const blob = new Blob([svg], {type: "image/svg"});
const url = URL.createObjectURL(blob);
const download = document.querySelector('#download');
download.href = url;
download.click();
URL.revokeObjectURL(url);
}
</script>
</body>
</html>
@iftkharhussain
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its works but downloaded SVG is different than the actual wavesurfer canvas

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