opus-media-recorder

* Try it!
* JS Fiddle example

opus-media-recorder is a MediaRecorder API polyfill written in ES6 and WebAssembly. It aims for cross-browser Opus codec support with various audio formats such as Ogg and WebM. opus-media-recorder can be used as a polyfill, or it can replace the built-in MediaRecorder since opus-media-recorder supports more MIME types.

opus-media-recorder uses WebAssembly compiled from popular libraries (e.g libopus, libogg, libwebm, and speexdsp) to ensure good performance and standards-compliance.

- Why opus-media-recorder?
- How to use
- Thing to know
- JavaScript
- Examples
- Installation
- Working with a bundler
- Simple JavaScript example (webpack)
- HTML





`

$3

`javascript
// Check if MediaRecorder available.
if (!window.MediaRecorder) {
window.MediaRecorder = OpusMediaRecorder;
}
// Check if a target format (e.g. audio/ogg) is supported.
else if (!window.MediaRecorder.isTypeSupported('audio/ogg;codecs=opus')) {
window.MediaRecorder = OpusMediaRecorder;
}
`

Browser support

Supported:

* Chrome >= 58
* Firefox >= 53
* Microsoft Edge >= 41
* Safari (macOS and iOS) >= 11

Browsers with issues:

* iOS 11.2 only: Not working due to a regression in WebAssembly: https://bugs.webkit.org/show_bug.cgi?id=181781

MIME Type support

* audio/webm
* audio/webm; codecs=opus
* audio/ogg
* audio/ogg; codecs=opus
* audio/wav or audio/wave

Limitations

* Does not support Video recording.
* opus-media-recorder throws generic Error objects instead of native DOMException.
* Because audio/wav is not designed for streaming, when mimeType is audio/wav, each dataavailabe events produces a complete and separated .wav file that cannot be concatenated together unlike Ogg and WebM. Therefore, it is recommended not to use timeslice option when calling start(), unless you know what the implication is.
* There is no SecurityError case implemented. (WIP)

How to build

1. To build from the source, you need Emscripten, yarn, Python 2.7 or higher, and basic C program build systems such as GNU Make.

2. yarn install to install JavaScript dependencies.

3. yarn run build to build. yarn run build:production to build files for distribution.

4. yarn run serve to run a test web server locally. Default URL is https://localhost:9000 (It has to be HTTPS). You might have to change DEV_SERVER_URL and DEV_SERVER_PORT to change the address of the local test server.

5. yarn run clean` to clean up build files.

$3

Changelog

See CHANGELOG.md.