ffmpeg.wasm is a pure Webassembly / Javascript port of FFmpeg. It enables video & audio record, convert and stream right inside browsers.
AVI to MP4 Demo
Try it: https://ffmpegwasm.github.io
$ npm install @ffmpeg/ffmpeg @ffmpeg/core
As we are using the latest experimental features, you need to add few flags to run in Node.js
$ node --experimental-wasm-threads --experimental-wasm-bulk-memory transcode.js
Or, using a script tag in the browser (only works in Chrome):
<script src="https://unpkg.com/@ffmpeg/[email protected]/dist/ffmpeg.min.js"></script>
<script>
const { createFFmpeg } = FFmpeg;
...
</script>Only browsers with SharedArrayBuffer support can use ffmpeg.wasm, you can check HERE for the complete list.
ffmpeg.wasm provides simple to use APIs, to transcode a video you only need few lines of code:
const fs = require('fs');
const { createFFmpeg, fetchFile } = require('@ffmpeg/ffmpeg');
const ffmpeg = createFFmpeg({ log: true });
(async () => {
await ffmpeg.load();
ffmpeg.FS('writeFile', 'test.avi', await fetchFile('./test.avi'));
await ffmpeg.run('-i', 'test.avi', 'test.mp4');
await fs.promises.writeFile('./test.mp4', ffmpeg.FS('readFile', 'test.mp4'));
process.exit(0);
})();Multi-threading need to be configured per external libraries, only following libraries supports it now:
Run it multi-threading mode by default, no need to pass any arguments.
Need to pass -row-mt 1, but can only use one thread to help, can speed up around 30%