iframeSeek.js

// Usage:
//
// var video = videojs('video_id');
// video.iframeSeek();
//
// To start the player at 30s
// $iframe[0].contentWindow.postMessage('startTime:30', '*')
//

(function(window, videojs) {
  'use strict';

  var plugin = function(options) {
    var player = this;

    window.addEventListener("message", function(evt) {
      var msg = evt.data

      if (msg.match(/^(.*)\:/)[1] == "startTime") {
        var seek = parseInt(msg.match(/\:(.*)/)[1]);

        if (seek) {
          player.ready(function(){
            player.currentTime(seek);
          });
        }
      }
    });
  };

  // register the plugin
  videojs.plugin('iframeSeek', plugin);
})(window, window.videojs);