W3C home > Mailing lists > Public > www-style@w3.org > May 2011

Re: [css3-speech] voice-volume

From: fantasai <fantasai.lists@inkedblade.net>
Date: Tue, 10 May 2011 20:23:34 -0700
Message-ID: <4DCA0136.7060502@inkedblade.net>
To: www-style@w3.org
On 05/10/2011 05:27 PM, Daniel Weck wrote:
> Fixed in the latest editors' draft. This was actually a regression bug, since the CSS21 Aural Stylesheet Appendix defined
> volume levels correctly. Note that I added the value "silent" to audio cues as "0" now means something different.
> http://dev.w3.org/csswg/css3-speech/#mixing-props-voice-volume
> http://dev.w3.org/csswg/css3-speech/#cue-props
> http://www.w3.org/TR/CSS21/aural.html#propdef-volume

I prefer having keywords each get their own definition, as in the CSS2 definition.
Also, I think you should define the keywords first, then define the <number> scale
in terms of the keywords, since that's actually how it works.
Finally, 'linear' should also get its own definition, since right now you're
mashing two concepts into one definition.

     No sound at all.
     The minimum audible level. Equivalent to '0'.
     Equivalent to '25'.
     The listener's preferred volume level. Equivalent to '50'.
     Equivalent to '75'.
     The maximum tolerable level. Equivalent to '100'.
     Any number between '0' and '100' inclusive, representing monotonically
     non-decreasing volume levels with the levels '0', '25', '50', '75' and
     '100' anchored by the volume levels defined for their respective keywords.
     Note that the resulting scale need not be linear.
     Percentage values are calculated relative to the inherited value, and
     are then clipped to the range '0' through '100'.
     When present, the 'linear' keyword indicates that the <number> represents
     a value on the linear volume scale between 'silent' and 'x-loud'.

CSS2 has some good recommendations and examples after the value definitions.
I suggest copying those into the spec and modifying as necessary instead of
jamming a long note into one of the definitions. Do add '50' to the list of
values the listener should be able to set. :)

Another comment: I think 'linear' is somewhat misleading, since the normal
0-100 scale /could/ be linear. (I think 'absolute' would be a better keyword
because 'absolute 0' is absolutely silent, but I'm open to suggestions.)
Also you should use
   [<number> && linear?]
instead of
   [<number> linear?]
since that allows the keyword and the number to swap places, which is customary
in CSS syntax where not ambiguous:
   voice-volume: 20 linear;
   voice-volume: linear 20;

For cues, do we really need 'silent'? Why wouldn't the author just remove the
cue, replacing with a rest if necessary?

Received on Wednesday, 11 May 2011 03:24:04 UTC

This archive was generated by hypermail 2.3.1 : Monday, 2 May 2016 14:38:45 UTC