Re: CSS3 Speech Module Comments (14th May Draft)

[The latest version is at <URL:http://www.w3.org/TR/css3-speech>.]

Andrew Thompson wrote:
> 2. voice-balance
> 
> The prose for this section mentions two properties, 'leftwards' and 
> 'rightwards' that are not included in the list of valid values given at 
> the beginning of the voice-balance definition. Should be consistent.
> 
> In general I approve of this simplification. Its probably actually 
> implementable, whereas the previous azimuth model wasn't really 
> practical.

azimuth might have been complex to understand but I feel that whatever 
gets selected, it should be future-proof enough to support *at least* 2D 
positioning of sound (left-right / front-back). I think the speech 
module should copy "background-position" here.

voice-balance:
     Value: [ [<percentage> | <length> ]{1,3} | [ [left | center | 
right] || [front | center | back] || [top | center | bottom] ] ] | inherit
     Initial:  	50% 0% 50%
     Applies to:  	all elements
     Inherited:  	yes
     Percentages:  	see below
     Media:  	aural

<percentage> [, <percentage> [, <percentage>] ]
(left-right front-back top-bottom): 50% 0% 50%  would refer to "centered 
both horizontally and vertically and positioned directly in the front of 
the listener". The actual distance (delay of sound, possibly 
attenuation) set by 100% should be calculated according to the user 
agent preferences (user should be allowed to select how wide sound stage 
he wants). 0% for left-right position means left, 0% for front-back 
means front and 0% for top-bottom means top.

This kind of property allows positioning the sound "inside one's head" 
(50% 50% 50%) in addition to the usual in "front of you", "on the left 
side", "on top of you" etc.

In the future, the voice balance could be considered as a shortcut for 
properties voice-balance-left-right, voice-balance-front-back, 
voice-balance-top-bottom or something similar.

Yep, I'm aware that actual implementation would be far away, but let's 
not limit the future with lesser syntax.

-- 
Mikko

Received on Monday, 23 June 2003 12:36:38 UTC