The standards used for video captioning are the US Access Board's Video and Multimedia standards for the provision of captions and audio descriptions and the DCMP Captioning Key guidelines for the captions themselves.
The basic UM standards for media include:
- closed captioning: synchronized humanly perfected verbatim transcripts (not captions provide directly from voice recognition processes)
- audio descriptions
DCMP captions standards are extensive but include basic requirements such as:
- Contain two lines of text, with around 32 characters per line of sans serif font.
- Show no less than 2 seconds and aim at a rate of about 120-130 words per minute presentation rate.
- Identify speaker names or identifiers followed by a colon and the dialogue - John: What do you mean?
- Indicate meaningful silences - Mother: Where have you been? Son: (silence)
- Indicate sounds in brackets - [horns honking], [wind whistling], [music], [awkward silence], [people shouting over each other]
- Indicate unknown sounds or words with several question marks - John: I'm going to the ???
- Use bold, italic or underline features - "That was REALLY cool!", "WHAT?"
- Use brackets to indicate timid or whispered words - Girl [whispers] I'm scared
- Use "..." when the dialogue is muffled or too low to discern - "I didn’t mean to hurt him, I …………… I was defending myself."
- Accurately transcribe language so viewers understand language register - "I told Johnny I was gonna get him for beatin' me in the race today. Cuz I was mad. I wanted to win…"