When you give a PowerPoint presentation live, what you say verbally is more important, probably more interesting, and certainly more fleshed out than the few words or pictures on the slides. But what if you want to send your presentation off to be viewed by a faraway audience or online viewers, where you will not be there to fill in the gaps? You could, of course, record a voiceover in PowerPoint, but maybe you have a cold and your voice isn't up to par. Or maybe your own voice sounds like fingernails on a chalkboard to you. Several new tools allow you to type the text you would normally say, and have text-to-speech technology (TTS) generate the voiceover for you. Later, if the content changes, editing the typed text will be way easier than re-recording an entire voiceover. Read on to learn about three different TTS tools for PowerPoint.
HelloSlide worked great. To add a computer-generated voiceover via TTS to your presentation, first save it as a PDF and then upload it to the HelloSlide website. The presentation must be in PDF format and can't be more than 100 MB (if your presentation is larger than this, try selecting minimum quality when you save it from within PowerPoint). Transitions and animations are not preserved, but if this isn't a problem for you, HelloSlide is a good option. You add the text for your slides right on the HelloSlide website. Presentations can be shared by linking to the presentation through the HelloSlide site or by using an embed code for playing elsewhere. On playback, your presentation will play one slide at a time for as long as it takes the voiceover to be read. I particularly enjoyed the English accent, but there are 20 languages to choose from. Be sure to type your text phonetically to get the best pronunciation quality (ie: instead of "live, online eLearning," type "lyve online ee-Learning").
With SlideSpeech, uploaded presentations don't need to be saved as PDFs, so that's kind of nice. Also, you don't have to enter the text on the site, because text is lifted right from the notes fields of your slides. If you typically enter the voiceover script there by default, this is probably a good option, as it will eliminate a step for you. Also on the plus side: after uploading your presentation and setting up the voiceover, SlideSpeech sends you a link to your presentation for easy editing and distribution. On the down side, the computer-y sounding voice doesn't sound as good as HelloSlide's options, and there are only two language choices (English and German). As with HelloSlide, typing your text phonetically will help with pronunciation.
There are a couple benefits to PowerTalk. For one, if you've already made your presentation 508 Compliant and added alt text to all of your images, this may be a very quick way to add TTS, since it reads directly from the slide as well as reading alt text on images. Additionally, the text is read as it appears on the slide, so if you're working with bullets, the text won't be read until that bullet appears. However, I've already beaten into the ground in my articles that you shouldn't be using bullets, so perhaps this is a moot point. On top of that, the TTS voice used is VERY robotified. I would consider PowerTalk a last resort that you turn to out of necessity. Since it reads right off the slide you won't be able to type the text phonetically and a lot of things may be mispronounced.
PS: Need some crafting that voiceover text? Not sure whether or not you should be reciting what's on the slide for your voiceovers? You might want to check out our Writing Effective eLearning Voiceover Scripts class.
AJ teaches a live, 3-hour class that offers tips/tricks for improving the look and feel of your PowerPoint presentations: Slide Sprucing: Remodeling Lackluster PowerPoint Slides for eLearning and Presentations.