Syncing HTML5 <video> with <audio> playback

Question

I am having track from one source, mute, and I\'d like to play background music over it using element. The tracks contain some time critical elements.

What would be th

Answer 1

Here is a simple solution using Popcorn.js inspired by this article.

$(function(){
var medias = {
    audio: Popcorn("#narration"),
    video: Popcorn("#video")
  },
  loadCount = 0,
  events = "play pause timeupdate seeking volumechange".split(/\s+/g); 


// iterate both media sources
Popcorn.forEach(medias, function(media, type) {

  // when each is ready... 
  media.on("canplayall", function() {

    // trigger a custom "sync" event
    this.emit("sync");

    // Listen for the custom sync event...    
  }).on("sync", function() {

    // Once both items are loaded, sync events
    if (++loadCount == 2) {
      // Uncomment this line to silence the video
      //medias.video.mute();

      // Iterate all events and trigger them on the video 
      // whenever they occur on the audio
      events.forEach(function(event) {

        medias.video.on(event, function() {

          // Avoid overkill events, trigger timeupdate manually
          if (event === "timeupdate") {

            if (!this.media.paused) {
              return;
            }
            medias.audio.emit("timeupdate");

            return;
          }

          if (event === "seeking") {
              medias.audio.currentTime(this.currentTime());
          }
          
          if (event === "volumechange") {  
        	  if(this.muted()) { 
        		  medias.audio.mute(); 
        	  } else {
        		  medias.audio.unmute(); 
        	  } 
        	  
        	  medias.audio.volume(this.volume());
          }

          if (event === "play" || event === "pause") {
            medias.audio[event]();
          }
        });
      });
    }
  });
});
});