Size Matters: Three Ways to Reduce eLearning Course Images

eLearning courses can sometimes grow to undesirable sizes and take up much more memory than expected. This can have a detrimental effect on loading speeds, and in the worst case scenario it can eat up too much hard drive space. One common culprit is image size.

Depending on the purpose of an image in your eLearning course, selecting an optimal format can alleviate the issue. However this may not be enough and the media folder can still snowball from a few kilobytes to a few megabytes.
Luckily the solution can be quick and painless. Here are three tricks for reducing your eLearning course image size:

For these examples I will be using this spooky ghost.


  • Posterize – This technique reduces the amount of colors used in an image. This function is generally found in color adjustment sections.

Gimp:                                           Photoshop:

When selected, you will be prompted to set the level. The higher the level, the more colors are used.

Since with this image there are already a limited amount of colors being used, the effect is barely noticiable even at lower posterize levels. By using the posterize function at “Posterize level 17,” we get a reduction of 44%.


  • Save for Web – This is an option that can be found in Photoshop. Pulling the image into Photoshop and saving it as a PNG-8 can reduce the image by 55%.


Our spooky ghost started at 18KB, but by running it through a few of the previously mentioned options, we get:


A 62% reduction!

Keep these tips in mind next time your eLearning course is loading slow. Your users will appreciate it.

By LHT Learning
| September 1, 2015