Preloading videos to prevent stuttering?

Mar 18, 2024

Hi everyone,

I am currently working on a training that includes a large number of short mp4 video sequences. Unfortunately, the videos frequently stutter when they start running, which is extremely annoying. This happens regardless of the quality settings. Is it possible to preload/cache all videos of a training into the RAM before launch in order to achieve smooth playback?

Thank you,
Christoph

15 Replies
Christoph Schmolz

Hi Ron,

thank you for your feedback!

The problem occurs with both settings. Adaptive might be slightly better but still way too choppy to be imposed on the customer. Playback is smoother when repeated, so I hope that preloading the clips will fix the problem. Most clips are only 1-2 seconds long and 150 KB to 1 MB in size, so I didn't expect any issues.

Jose Tansengco

Hi Christoph, 

I agree that using the adaptive video quality setting should help here since it will allow a preloaded, low-quality version of your videos to load for learners with slow internet speed. 

Since you've already tried using that option, you can check out additional tips for working with a video-heavy course here: 

Additionally, you'll also want to test your course in a different environment to see if the loading issue is only present in your course hosting platform. If you can replicate the behavior in SCORM Cloud, please open a case with our support team here so we can check how your course is currently set up.

 

Christoph Schmolz

Hi Jose,

thank you for your advice, but the problem does not appear to be related to internet speeds. The stuttering of the first video frames also occurs when I run the published course locally.

When restarting the slide once or twice, playback is smooth without the initial jittering. This leads me to believe that Storyline does not properly fill the browser cache in the beginning. I need to find a way to get this done before running the training.

Christoph Schmolz

Hi Ron, most videos were rendered in Keyshot, some in Premiere Pro. I've already tried to make the files as small as possible using Handbrake but that does not appear to have any effect on playback.

It looks as if the first couple of frame jump back and forth before a clip actually start playing. That's a huge problem for me since the training relies on seamless transitions between product views.

Christoph Schmolz

Hi Ron, I have put together a sample file with three tiny mp4 video clips. Note the annoying stuttering that occurs at the beginning of each clip. It appears to be more severe in Firefox than in Chrome/Edge but in neither case can the customer be expected to accept this.

Please find attached the story file.
An online version (published with adaptive quality) can be viewed here:
https://360.articulate.com/review/content/58363cd6-ad26-4749-9702-dc9cca633134/review