Captions display television's auditory information in visual form.
Captions are synchronized with speech patterns and changes in camera angles to convey a sense of rhythm and pace. Engineers transcribe each program's entire script onto specially programmed microcomputers. The dialogue is then edited in to read as captions, yet complete enough to give hearing-impaired viewers a full sense of the speaker's words. To make the information as accurate as possible, captions also identify sounds, music and off-screen speakers. Captions are timed to match audio and lip movements, then carefully placed to convey an accurate sense of who is speaking.