W3C home > Mailing lists > Public > public-html-a11y@w3.org > June 2011

Re: Meaning of audio track kind 'descriptions'

From: Mark Watson <watsonm@netflix.com>
Date: Tue, 21 Jun 2011 22:45:02 -0700
To: Silvia Pfeiffer <silviapfeiffer1@gmail.com>
CC: David Singer <singer@apple.com>, Bob Lund <B.Lund@cablelabs.com>, "HTML Accessibility Task Force" <public-html-a11y@w3.org>
Message-ID: <62679AA2-EFE1-4652-BC27-CCBC91BDDC41@netflix.com>

On Jun 22, 2011, at 2:16 AM, Silvia Pfeiffer wrote:

> On Wed, Jun 22, 2011 at 3:32 AM, Mark Watson <watsonm@netflix.com> wrote:
>> I think this is a matter of opinion and eventually gets resolved through
>> feedback from real users. I doubt *users* want to continuously adjust the
>> relative volume of the tracks, so we're talking about automatic client
>> capabilities, perhaps based on user preference settings, which do the
>> ducking. But still these have only one degree of freedom (relative volume of
>> the two tracks), whereas the content creator has many (relative volume of
>> the many source tracks).
>> So I think it's equally unlikely that client-side ducking is always better
>> than professional mixing.
> Well, we are not talking about how a video's main audio track is
> composed - of course a professional sound editor will create a better
> mix of the many input channels that are necessary to be synchronized.

I am talking about that, though.

> We are only talking about how a human or computer-created voice that
> is spoken over the top of an existing mix stands out in front of that
> mix.

I am also considering other kinds of commentary.

> This is a simple matter of turning the main audio track
> quieter/louder (i.e. ducking). If I as a user cannot discern the
> description voice over the top of the main mix, then I turn the main
> mix down. Surely that is always better than a fixed mix of the audio
> description with the main audio where I am dependent on how well the
> person that does the sound mix can hear the voice in front of the main
> audio mix.

I agree that having some kind of user control is a good thing. But I'm still not sure it's "always" better, especially when considering other kinds of commentary. Actually, my point is even weaker than this - just that descriptions provided as an alternative to the main audio should not be considered "legacy" and should be provided for in the spec.

The object is to adjust the main audio so that the descriptions are easily audible. The main audio consists of many components of varying importance to the experience of the content. So someone who is re-mixing those original components can adjust their volume according to their importance, perhaps attenuating some aspects more than others, or removing some completely during the time that the description is spoken.


> Silvia.
Received on Wednesday, 22 June 2011 05:45:24 UTC

This archive was generated by hypermail 2.4.0 : Friday, 20 January 2023 19:59:02 UTC