Closed Captioning
SMPTE definition: Captions for the Hearing Impaired are a textual representation of the audio track, usually including all sounds, and usually in the same language as the audio track dialog, intended for hearing impaired audiences.
- Transcribes dialogue, sound effects, relevant musical cues, and other relevant audio information
- Able to shift on-screen position within 80% safety margin to prevent obscuring visual elements
- Unable to alter font style or font size
- Black background
- Only visible when the user enables CC
Open Captioning
- Similar to closed captioning but permanently visible
- Used primarily for closed captioning approvals and network clearance
Subtitling
SMPTE definition: Subtitles are a textual representation of the audio track, usually just the dialog and usually in a language other than the audio track dialog, intended for foreign language audiences.
- Translates dialogue or on-screen text into another language but does not include sound effects
- Able to alter font style and font size
- Transparent background
- Permanently visible
SDH (subtitling for the deaf and hard-of-hearing)
- Similar to subtitling but uses the same language as the dialogue and does include sound effects, relevant musical cues, and other relevant audio information
Audio Description (RoW) / Described Video (Canada)
FCC definition: Audio description is audio-narrated descriptions of a television program's key visual elements. These descriptions are inserted into natural pauses in the program's dialogue. Audio description makes television programming more accessible to individuals who are blind or visually impaired.
- Provides descriptive narration of key visual elements
- Inserted during natural pauses in the audio or during non-essential dialogue
- Only audible when the user enables Secondary Audio Program (SAP)
- Also known as Descriptive Video Service and formerly known as Video Description