This page archives past NCAM projects. While the information remains relevant, some resources referenced are no longer available, so links to them have been removed.
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Text-to-speech conversions of on-screen information
NCAM has created brief QuickTime clips that show various approaches to making on-screen information more accessible to blind and visually impaired viewers. Below are videos that demonstrate automated text-to-speech (TTS) conversions of on-screen information with synchronized playback. In each video the main audio channel is automatically lowered as the secondary channel, containing TTS audio, is raised. When the TTS is finished playing, the main audio channel is raised to its previous level.
Select a clip from the list below to view in the QuickTime Player. All contain closed captions. To see the closed captions from a player embedded in a Web page, right-click on the movie and choose Show Closed Captioning. Note that this feature is available in QuickTime Player 7.5 only. If you are using QuickTime 7.4.x and want to see the captions, download the clip (right-click on a link below and choose Download/Save Link), open the movie in the QuickTime Player, open the View menu and choose Show Closed Captioning.
- One TTS voice reading a single stream of data (school closings)
- Two TTS voices reading different data streams (school closings and lottery drawing)
- One TTS voice reading an emergency crawl (power outage)
Automatically relocated closed captions
Below are links to brief videos that demonstrate how closed captions can be automatically relocated to make room for on-screen crawls or other text displays. These movies contain open captions-- that is, you cannot turn them off.
- Captions in the upper third of the video relocated to make room for an emergency crawl
- Captions in the lower third of the video relocated to make room for blocks of text
The text-to-speech and caption-relocation processes shown in these clips were accomplished with software created by Tim Heidmann at Serious Intent Entertainment, running on a Pinnacle Systems Dekocast, which is used by broadcasters to merge on-screen graphics with video. Read a technical article about how the DekoCast can be used to relocate captions and merge TTS audio into a broadcast stream.
NCAM wishes to thank project partner WCVB for granting permission to use their news footage in these clips.
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