# WebViewer Audio
[WebViewer](https://www.pdftron.com/webviewer) is a powerful JavaScript-based PDF Library that's part of the [PDFTron PDF SDK](https://www.pdftron.com). It allows you to view and annotate PDF files on your web app with a fully customizable UI.
This is an addon for WebViewer that allows loading media files (.mp3, .mp4, ogg, webm, etc.), so that their audio tracks can annotated and redacted.
Also, try out the react sample [here](https://github.com/PDFTron/webviewer-audio-sample). It shows how to integrate WebViewer and WebViewer-Audio with a server component for the saving of annotations.
## Demo
https://webviewer-audio.web.app/
## Initial setup
Before you begin, make sure your development environment includes [Node.js and npm](https://www.npmjs.com/get-npm).
## Install
```
npm install @pdftron/webviewer-audio
```
## How to use
Here is an example of how WebViewer and WebViewer-audio could be integrated into your application.
```javascript
import React, { useRef, useEffect } from 'react';
import WebViewer from '@pdftron/webviewer';
import { initializeAudioViewer } from '@pdftron/webviewer-audio';
const App = () => {
const viewer = useRef(null);
useEffect(() => {
WebViewer(
{
path: '/webviewer/lib',
},
viewer.current,
).then(async instance => {
// Extends WebViewer to allow loading media files (.mp3, .mp4, ogg, webm, etc.)
const {
loadAudio,
} = await initializeAudioViewer(
instance,
{
license: '---- Insert commercial license key here after purchase ----',
}
);
// Load a media element at a specific url. Can be a local or public link
// If local it needs to be relative to lib/ui/index.html.
// Or at the root. (eg '/audio.mp3')
const audioUrl = '/audio.mp3';
loadAudio(audioUrl);
});
}, []);
return (
);
}
export default App;
```
Also see the [React sample](https://github.com/PDFTron/webviewer-audio-sample), for a complete solution, with further customizations.
### Loading as a Script Tag
If your environment can not import WebViewer Audio from the module, you can instead include WebViewer Audio as a script tag. Simply, take the file `node_modules/@pdftron/webviewer-audio/dist/main.js` and add it to your project's html page. WebViewer Audio requires the react library, so include that as well.
```html
...
```
This will add the object `WebViewerAudio` to the window. This object contains `initializeAudioViewer`. So the previous code can be changed to:
```javascript
...
const license = '---- Insert commercial license key here after purchase ----';
const {
loadAudio,
} = await window.WebViewerAudio.initializeAudioViewer(
instance,
{ license },
);
...
```
### Builds
Webviewer Video comes with two builds. The default build does not include `React` and `React-DOM` in the bundle and both must be provided by the parent code. The other build includes `React` and `React-DOM` in the bundle. See the AngularJS example below on how to load the build that includes `React`.
```javascript
import { Component, ViewChild, OnInit, Output, EventEmitter, ElementRef, AfterViewInit } from '@angular/core';
import { Subject } from 'rxjs';
import WebViewer, { WebViewerInstance } from '@pdftron/webviewer';
import { initializeAudioViewer } from '@pdftron/webviewer-audio/dist/main-with-react';
@Component({
selector: 'app-root',
templateUrl: './app.component.html',
styleUrls: ['./app.component.css']
})
export class AppComponent implements OnInit, AfterViewInit {
@ViewChild('viewer') viewer: ElementRef;
wvInstance: WebViewerInstance;
@Output() coreControlsEvent:EventEmitter = new EventEmitter();
private documentLoaded$: Subject;
constructor() {
this.documentLoaded$ = new Subject();
}
ngAfterViewInit(): void {
WebViewer({
path: '../lib',
}, this.viewer.nativeElement).then(async instance => {
const license = `---- Insert commercial license key here after purchase ----`;
this.wvInstance = instance;
const audioInstance = await initializeAudioViewer(
//@ts-ignore
instance,
{
license,
}
);
// Load a video at a specific url. Can be a local or public link
// If local it needs to be relative to lib/ui/index.html.
// Or at the root. (eg '/video.mp4')
const audioUrl = '/audio.mp3';
loadAudio(audioUrl);
})
}
ngOnInit() {
}
getDocumentLoadedObservable() {
return this.documentLoaded$.asObservable();
}
}
```
## Documentation
[API documentation](https://www.pdftron.com/api/audio/)
## WebViewer APIs
See @pdftron/webviewer [API documentation](https://www.pdftron.com/documentation/web/guides/ui/apis).
## License
WebViewer Audio will run in trial mode until a license is provided. For more information on licensing, please visit our [website](https://www.pdftron.com/licensing/).