508 Compliance

We're looking at how to make our courses used for Algebra accessible to students with hearing impairments. We use a lot of audio and video. I know captioning can be built in to those videos through video editing software and I know we could add captions using layers and/or text boxes in Storyline.

While at a conference a few years ago I saw an Articulate person demonstrate how to use some 3rd party assistive technology to transfer voice to text. What I saw was a video playing from the Articulate output and it being changed to text by this third party tool. Does anyone know what that third party tool might have been?