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Re: Captioning Compliance

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From: Andrew Kirkpatrick
Date: Mar 19, 2013 2:24PM

Those are good general concepts, but shouldn't be regarded as hard and fast rules. Some comments:

- One to three lines of text appear onscreen all at once, stay there for
three to seven seconds, and are then replaced by another caption.

I generally try to avoid 3 lines, in order to minimize interference with content. Also makes the caption faster to read so the user can focus on the content more.

The 3-7 second rule is not helpful as a hard and fast rule. If a caption is short and followed quickly by other caption text, then less than three seconds may be fine. If the audio has a lot of spoken information in a short period of time, you either need to compromise on the time each caption is in view or on the matching of the captions to the audio in a verbatim way, or a little of each.

- Timed to synchronize with the audio.

Absolutely.

- Do not cover up graphics and other essential visual elements of the
picture.

Absolutely, when possible. When the entire frame is filled with important content, a tough decision needs to be made though.

- Require the use of upper and lowercase letters.

This is best practice, but no one is going to be sued under the ADA due to using all caps. You can still see this being done on TV sometimes, but mixed case is definitely better. When procuring captioning services, ask for mixed case and you'll get it.

- Use a font similar to Helvetica medium.

What is "Helvetica medium"? There's lots of argument about the best font for captioning, and there has never been agreement. Don't pick something that is hard to read (so Helvetica is ok) and if users ask for something different, try something else.

- Have good resolution.

I'm not sure what this means in the context of Camtasia - when captions are text they are rendered clearly. If the captions are "burned in" as part of the video then low video resolution will result in harder to read captions.

- Include not more than 32-characters-per-line.

An area of debate. Some captioning agencies will suggest longer.

Other "rules" that come to mind:
- captions should be a verbatim representation of what is spoken, although you can edit out the filler (uh, ah, etc.)
- follow conventional rules for grammar and punctuation, but don't correct the grammar of the speaker
- always check your spelling
- end punctuation always indicates the end of a caption; the next sentence begins with a new caption
- include important non-speech information, such as sound effects or speaker identification
- break captions at natural pauses or intervals, if possible
- If there is no speech or sound for 5 seconds, the previous caption should be cleared from the screen.
- Music should be indicated by the use of the Unicode eighth note.


Thanks,
AWK

Andrew Kirkpatrick
Group Product Manager, Accessibility
Adobe Systems

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