HTML5 and Flash slide loading ?

Hoping someone can provide some insight into how the new HTML5 publish only option impacts the loading of pictures and vids.  We recently moved our courses into HTML5 mode and it seems just a little sluggish and slower when loading pics and video (Mp4).  We understand that flash is dead and are embracing the HTML5 and do not want to add the Flash back up.  From what I understand Flash  loads a series of slides in the background so they are always ready to go where as HTML5 loads one at a time.  

Wondering if anyone has a fix for slow loading pics and vids ?  These are not big vids - roughly 40 sec at most.

Will HTML5 ever preload slides or is this just not possible ?

3 Replies
Alyssa Gomez

Hi there Tracy! I can shed some light on this.

To make playback as smooth as possible, your published Storyline courses will preload content in the following order:

  1. Assets are loaded for the first slide (or the current slide when resuming), so the course can begin playing right away.
  2. Assets are then loaded for the next three slides to prevent playback delays.
  3. Assets are then loaded for the remainder of the course.

One thing to note: HTML5 content doesn't preload videos. However, Storyline progressively streams videos so learners won't have to wait for each video to fully download before it begins to play.

Now, let's talk about the slow loading you're seeing in the HTML5 output. Where is the output hosted--on a web server or a LMS? 

Tracy Arron

Thanks for the fast response Alyssa !

It is hosted on an LMS and we never had an issue when we published with flash.  We always try and make the jpegs/pngs the same size as the slide or a touch bigger.  It seems this is happening mostly on the initial slides of a course.

With the video would it help to back it up by 1 sec for auto play ?  Or not use auto play at all ?

We are really trying to do everything in HTML5 as the writing is on the wall.



Alyssa Gomez

Hi Tracy,

Thanks for confirming the course is hosted on a LMS. You might see improved loading time by backing up the video 1 second on the timeline, but I would want to test your file to be sure. 

What version of Storyline are you using? Would you be willing to share your project file with me? I'd like to test it in SCORM Cloud to get a better idea of how the content performs in various browsers.