Course File Size

Hi Guys,

Unsure if anybody would be able to shed some light into my question, nevertheless here goes:

I am building a course in SL and I intend to publish the course to a website server. I estimate that the published course would consist of approx 1400 slides (average of 20 slides per scene). Each slide consists of an average file size of :

Graphics - 20KB (after using a jpg file compression utility)

Sound - 2 x sound files @ 100KB = 200KB (file type:- OGG. Good quality and best file size)

Slide consisting of 3 x text boxes including a design template from SL (cannot confirm actual file size)


When I save a slide as a SL template, the file size including all of the above content, totals 2.0MB. Rather huge for a single slide. If I do the math, this would easily equate to 2.7 GB for the entire course. My questions are as follows:

1. Once the course is published, is the final published file compressed? If so, does anybody know what the compression ratio is? (i.e.: if the.story file = 2.7 GB, what is the possible file size after the course is published?)

2. If point 1 above proves to be 2.7 GB after having the course published, would the user experience slow performance? If I do the math, If I allocate bandwidth of 0.4 MBits/sec (i.e.: <1MB) and if the typical PC has RAM of at least 1 GB, would there be any performance degradation?

3. How does SL allocate memory? Is the entire publish file loaded into memory and then delivered to the user?

There are so many factors which could impact performance and I just need some clarity so I can continue with the course. I have stopped building the course until I can research something which provides a guideline around building large enterprise platforms using SL. 



1 Reply
Ashley Terwilliger

Hi Shawn and welcome to Heroes! 

It sounds like a fairly large course - which I've seen other users discussing similar sized courses here, so I hope they're able to chime in with their expertise. 

In regards to your specific questions, I wanted to provide some resources. 

1. The final published output is compressed, although I don't know that there is a particular formula or ratio that's used. Videos, images, text are all dealt with separately and you can even adjust the compression/quality settings prior to publish as indicated here. As an example here is an explanation of video compression. 

2 and 3. Slow performance will depend on the users set up, but Storyline will preload content as described here to help prevent delays in playback. I'd also make sure that the users are up to date with their browsers, flash players, etc. and you can find the minimum requirements for running Storyline here. 

You may also want to look into where you're hosting the course to see if they have any limitations or options to allow you to chunk the course into sections that are still connected. 

I hope that helps, and there are a number of other forum threads or this one where users discuss similar issues.