Captioning

The conversion of spoken dialogue, sound effects, and other auditory information into synchronised text displayed alongside audiovisual content. Captioning makes audio content accessible to people who are deaf or hard of hearing and also benefits people in noisy environments, non-native language speakers, and those with cognitive or processing differences. Closed captions can be toggled on or off by the viewer, while open captions are permanently embedded. In live settings, captions may be provided through CART (Communication Access Real-time Translation) or automatic speech recognition. WCAG addresses captioning through Success Criteria 1.2.2 (Level A for prerecorded media) and 1.2.4 (Level AA for live media). Research increasingly recognises that effective captioning goes beyond text accuracy to include speaker identification, emotional tone, and environmental sounds.