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Re: Audio description in WCAG 2.1 AA success criterion1.2.5


From: Guy Hickling
Date: Apr 23, 2021 6:02PM

The root cause of the problem here is that the Understanding document
attempts to override or restrict what the normative success criterion
specifies. A few other success criteria suffer from this problem as well.

SC1.2.5 quite clearly states "Audio description is provided for all
pre-recorded video content ...". It specifically says "all", without any
caveats. But the Understanding document then tries to alter that by
claiming that this audio provision is to be done "During existing pauses in
dialogue....". The implication is plain - as so many web dev people have
assumed - that if there are no pauses available that let's them out.

Not only does that contradict or soften what the SC itself says, but it
also blandly ignores the fact that about half of all videos ever made have
hardly any spaces in the audio for adding extra. It also ignores that many
videos - particularly educational and technical ones - often have detailed
diagrams or illustrations that require very long spaces to insert a

Creating an Understanding that tries to restrict what the corresponding SC
says is a failure of proper process. We should never see a purely
explanatory, informative document trying to reword or amend the normative

All new success criteria go through a long process of discussion by many
consultants and contributors. About half way through that process
discussion is thrown open to the public. However the same care is not
always taken with the Understanding documents where, usually it seems to
me, one person is given the job of writing the Understanding. Discussion
and amendment of that is still allowed, but does not in my experience
receive the same level of attention as the normative SCs have already
received. (Quite naturally, I think, I'm not criticising; having gone to
great effort to create the SC, people naturally move on to other important

Unfortunately that has left us with a few cases where either the intent of
the SC is watered down, or confusion is caused later for the rest of the
web dev world - as in this particular case, witness all those sources Steve
mentioned that have come to a wrong view about it.

So I think a change in process is needed. I hope it will change in WCAG 3,
to ensure Understanding documents do not ever contradict or restrict what
their SC says, or appear to do so, or cause confusion by saying something
that the SC does not require.

A check should be built into the W3C process for SCs to ensure people vet
each new Understanding document, including subsequent edits and amendments,
to ensure nothing in that document goes against what the carefully crafted
SC already specifies.