iSpring is a free PowerPoint add-in that will convert your static presentation slides into a standalone Flash movie. iSpring supports all formats including .pptx that was introduced with PowerPoint 2007.
There are two advantages here – the converted presentation will weigh less (because of Flash compression) and second, the Flash movie will preserve all slide transitions, hyperlinks and animation effects that are otherwise lost when you upload slides to PowerPoint hosting services.
If you have any audio narrations or video clips in the PowerPoint file, they’ll also become available in the published Flash movie.
iSpring converts standard PowerPoint shapes and options into vectors, pixelation won’t happen if your audience decides to view the Flash presentation in full-screen.
Here’s another related guide on converting PowerPoint into video.