# [wavesurfer.js](https://wavesurfer-js.org)
[](https://www.npmjs.com/package/wavesurfer.js)
 [](https://gitter.im/katspaugh/wavesurfer.js?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
Interactive navigable audio visualization using Web Audio and Canvas.
[](https://wavesurfer-js.org)
See a [tutorial](https://wavesurfer-js.org/docs) and [examples](https://wavesurfer-js.org/examples) on [wavesurfer-js.org](https://wavesurfer-js.org).
## Browser support
wavesurfer.js works only in [modern browsers supporting Web Audio](http://caniuse.com/audio-api).
It will fallback to Audio Element without graphics in other browsers (IE 11 and lower). You can also try [wavesurfer.swf](https://github.com/laurentvd/wavesurfer.swf) which is a Flash-based fallback.
## FAQ
### Can the audio start playing before the waveform is drawn?
Yes, if you use the `backend: 'MediaElement'` option. See here: https://wavesurfer-js.org/example/audio-element/. The audio will start playing as you press play. A thin line will be displayed until the whole audio file is downloaded and decoded to draw the waveform.
### Can drawing be done as file loads?
No. Web Audio needs the whole file to decode it in the browser. You can however load pre-decoded waveform data to draw the waveform immediately. See here: https://wavesurfer-js.org/example/audio-element/ (the "Pre-recoded Peaks" section).
## API in examples
Choose a container:
```html
```
Create an instance, passing the container selector and [options](https://wavesurfer-js.org/docs/options.html):
```javascript
var wavesurfer = WaveSurfer.create({
container: '#waveform',
waveColor: 'violet',
progressColor: 'purple'
});
```
Subscribe to some [events](https://wavesurfer-js.org/docs/events.html):
```javascript
wavesurfer.on('ready', function () {
wavesurfer.play();
});
```
Load an audio file from a URL:
```javascript
wavesurfer.load('example/media/demo.wav');
```
## Documentation
See the documentation on all available [methods](https://wavesurfer-js.org/docs/methods.html), [options](https://wavesurfer-js.org/docs/options.html) and [events](https://wavesurfer-js.org/docs/events.html) on the [homepage](https://wavesurfer-js.org/docs/).
## Upgrade
See the [upgrade](https://github.com/katspaugh/wavesurfer.js/blob/master/UPGRADE.md) document if you're upgrading from a previous version of wavesurfer.js.
## Using with a module bundler
Install Wavesurfer:
```bash
npm install wavesurfer.js --save
# or
yarn add wavesurfer.js
```
Use it with a module system like this:
```javascript
// import
import WaveSurfer from 'wavesurfer.js';
// commonjs/requirejs
var WaveSurfer = require('wavesurfer.js');
// amd
define(['WaveSurfer'], function(WaveSurfer) {
// ... code
});
```
## Related projects
For a list of projects using wavesurfer.js, check out
[the projects page](https://wavesurfer-js.org/projects/).
## Development
[](https://github.com/katspaugh/wavesurfer.js/actions?workflow=wavesurfer.js)
[](https://coveralls.io/github/katspaugh/wavesurfer.js)
Install development dependencies:
```
npm install
```
Development tasks automatically rebuild certain parts of the library when files are changed (`start` – wavesurfer, `start:plugins` – plugins). Start a dev task and go to `localhost:8080/example/` to test the current build.
Start development server for core library:
```
npm run start
```
Start development server for plugins:
```
npm run start:plugins
```
Build all the files. (generated files are placed in the `dist` directory.)
```
npm run build
```
Running tests only:
```
npm run test
```
Build documentation with esdoc (generated files are placed in the `doc` directory.)
```
npm run doc
```
If you want to use [the VS Code - Debugger for Chrome](https://github.com/Microsoft/vscode-chrome-debug), there is already a [launch.json](.vscode/launch.json) with a properly configured ``sourceMapPathOverrides`` for you.
## Editing documentation
The homepage and documentation files are maintained in the [`gh-pages` branch](https://github.com/katspaugh/wavesurfer.js/tree/gh-pages). Contributions to the documentation are especially welcome.
## Updating the NPM package
When preparing a new release, update the version in the `package.json` and have it merged to master. The new version of the package will be published to NPM automatically via GitHub Actions.
## Credits
The main maintainer: 
[Thijs Triemstra](https://github.com/thijstriemstra)
Many thanks to [all the awesome contributors](https://github.com/katspaugh/wavesurfer.js/contributors)!
## License
[](https://opensource.org/licenses/BSD-3-Clause)
This work is licensed under a
[BSD 3-Clause License](https://opensource.org/licenses/BSD-3-Clause).