The best way to share multimedia presentation slides online

Sharing slides and presentations online is surprisingly difficult and requires the use of multiple online services to recreate the experience of the live presentation


At a recent STFC Public Engagement Symposium, I gave a presentation to around 120 researchers and science communication specialists introducing the world of social media. In my talk I explained how social media and social networks can be used to blend science into the mainstream cultural discussions.

I used many slides with graphs, maps and diagrams to illustrate my points, and many people have since asked me to share the slides with them. To share these slides effectively turns out to be not as easy as I hoped.

In any public talk making use of supporting materials on slides, having the slides alone without a commentary is  in large part useless, so a voice narration and subtitles can be used to recreate the live experience that the audience experienced.

Narration/Voice-over & Subtitles

I used PowerPoint 2007 to prepare the slides. Recording voice narration is extremely simple. A good microphone is needed, but once you have that, select ‘Voice Narration’  in the Slide Show ribbon and off you go; it will even record the timings for you to synchronise the slide changes and animations.

This was my first voice narration and it worked well. Next time I will be careful to reduce odd background noises, shuffle less, and not click the mouse.

I also added brief subtitles to the slides in case sound isn’t available. This will at least fill in some of the gaps. Surprisingly there is no easy way to accomplish this in PowerPoint 2007. It would be useful if the Notes section could be animated in some way. The only workable option is to use text boxes and animate them.  

Sharing the  presentation: requirements

The most straightforward option to share is to create a PDF and email it around. This is quite primitive, destroys the audio track and does not handle the transitions well.

A second option, is to host the presentation file on our website, circulate the web page link and allow people to download the file. That assumes they have PowerPoint 2007 on Windows, or some way of reading .pptx files on Mac or Unix systems. A straight link doesn’t allow the content to be easily shared.

A third option is to record the screen, whilst making a separate voice recording, mix the two together in video editing software, and upload to YouTube. I like the idea of sharing on YouTube, but I want to do it easily by converting the PowerPoint file.

My ideal scenario for sharing a presentation includes:

  • playing the slides in order and preserving the animation
  • playing the narration soundtrack in synchronisation
  • produce a transcript of the slide text
  • produce a video of the presentation including the animation and narration
  • not be overwhelmed with advertising and other screen clutter
  • be easy to find and share links on social networks
  • have a version that works on mobile devices
  • cope with large files
  • original slides can be downloaded

For this exercise, I recorded the audio at high quality, but I could probably reduce the quality next time to shrink the file size. Adding audio to the original presentation took the file size from 3.7 MB to 177 MB.

Sharing the presentation: practice

There are 4 online sevices that offer a good route for sharing presentations in a social way:


Each service has its strengths and weaknesses. Visual communication company m62 have made a comprehensive study of each of them which is a good starting point for deciding which to use. Since their study in January 2010, no further serious contenders have joined the list. is the most popular of the sites, and is ranked 251 in global traffic, so the presentation has to be listed there to ensure it is widely seen. However, animations are stripped out and audio is thrown away. There is an option to add an audiotrack on the site, but that is too tedious even to think about. But the presentation works and on mobile too, and the transcript is excellent. This is the only service that allow the original slides to be downloaded. can handle the audio and animations, but is restricted to 100 MB maximum file size. will handle the file size, audio and animations, but makes a charge if the presentation exceeds 5 minutes, and is incredibly slow to upload and convert files. produces the best slideshow online with narration and animation, makes a video version and uploads to YouTube with a minimum of fuss. Unfortunately, doesn’t produce a transcript. Also, in this example, my presentation is 28 minutes long, and the YouTube limit is 15 minutes, so the video gets chopped in half. Either you are forced to work with 15 minute chunks, or just use the site. Downloading of the original presentation isn’t an option on this site.

In conclusion, sharing presentations online effectively is surprisingly difficult. I have had to use two separate services – slideshare and mybrainshark – to create all the components on my wish list. But now, I can share those links widely, and offer my audience a range of methods to get at the information again.

Appendix: detailed observations

Function: kills all the animations and voice track, shapes cover each other up. File limit of 100MB. Original slides can be downloaded.

Audience: massive – number 1 site for sharing slides. Global traffic rank: 251 from

Advertising: everywhere and very distracting. Also has tendency to have broken links and blank boxes.

Transcript: excellent. All text, even from animated text boxes

Pro:  $190 per year, ad free,  more control

Video: no conversion options

Mobile: works nicely on mobile iOS with no advertising

Function: keeps all animations and voice track

Audience: global traffic rank: 30,698 from

Advertising: more discreet than slideshare

Transcript: excellent representation of all the text, even from animated text boxes

Pro: $195 per year, ad free, more control

Video: no

Mobile:  very poor, does not even scale

Function: keeps all animations and voice track

Audience: global traffic rank: 5840 from

Advertising: yes, a lot making it quite cluttered

Transcript: good representation of all the text

Pro: $30 per year

Video: video can be made – very slow conversion. Charge for length greater than 5 minutes. no simple connection to YouTube.

Mobile: no mobile version of site, but slide shows do play in browser pages.

Function: really easy to use. Fast and sleek. The most satisfying experience to upload and convert to video.

Audience: global traffic rank: 29,561 from

Advertising: none

Transcript: no transcript. Just slide titles.

Pro:  $120 per year to remove branding, extra to add training features

Video: very fast video conversion with option to share onto YouTube, but beware YouTube 15 minute limit.

Mobile: free app from app store, plays slides as video, but in app searching is very poor.