Get metadata on MP4 video using mp4box.js

mp4info.js

import * as MP4Box from 'mp4box';

// returns a Promise that resolves to video metadata using MP4Box.js
export const getMp4Info = async (videoBlob) => {
  const mp4boxfile = MP4Box.createFile();
  return new Promise((resolve, reject) => {
    mp4boxfile.onReady = function (info) {
      resolve(info);
    };
    mp4boxfile.onError = function (e) {
      reject(e);
    }
    videoBlob.arrayBuffer().then((buffer) => {
      buffer.fileStart = 0;
      mp4boxfile.appendBuffer(buffer);
    });
  });
};