MP4Box is a great command line tool for all sorts of file manipulations. Inspired by this tool, we decided to create a tool for Javascript-based manipulations of MP4 files. We are proud to announce MP4Box.js.
MP4Box.js is meant to provide similar features to MP4Box but adapted to the JavaScript world and needs, in particular in browsers or in environments like nodejs. It is currently possible to do many things such as: on-the-fly in-browser fragmentation of non-fragmented files for consumption using the Media Source Extensions API; or to get media information such as number, type, duration of tracks; or to extract media data … It is designed to work with large files and is intended to support as many types of MP4 files as possible. Several demos are already available.
Like MP4Box, MP4Box.js is open-source, hosted on GitHub here. The work is still very much in progress, but the current version is considered stable enough for people to use it. If you have feature requests or bug fixes, please file issues on GitHub. If you use MP4Box.js in your projects, let us know as well.