[css3-speech] Comments: 'voice-volume'

* 'voice-volume'
<numbers> are defined as a volume scale ranging from 0 to 100, and  
keywords are defined as a 6-point scale to cover the same range, but "the  
mapping of these to numerical volume levels is implementation dependent".

My take would rather be to match the 6-point scale to the numeric scale -  
mapping these values to the exact amplitude will be implementation  
dependent. In the most flexible case I might think of defining a keyword  
as covering a range of numeric values (say, e.g., 'medium' as suggested to  
be matched somewhere in the range between 50 and 70). I am sure there is a  
rationale behind defining two scales to cover the same range and leaving  
the mapping completely open.

I imagine one of the problems rising by definig a mapping between keywords  
and numbers in the spec might be that a user could perceive, once he tuned  
the volume of his speakers to be at a comfortable level when the 'medium'  
value occurs, he might have problems with an 'x-loud' being too much, or,  
vice-versa, once setting his speakers to suit his perception of 'x-loud',  
'medium' might be too soft.

My take would be to define the numeric value 0 of mapping to 'silent' and  
100 mapping to 'x-loud'. To allow user definig the excursion between  
'medium' and 'x-loud', I would suggest introducing something like an  
@rule: '@volume' defining the matching point between 'medium' and a  
<number>. If not explicitly defined it defaults to '@volume 60'. This  
means that the user agent matches the remaining keywords to the respective  
numbers:
x-soft = 20
soft = 40
loud = 80

Defining '@volume' to a different value, and thus matching 'medium' to  
something different than 60, would make the UA re-calculate the mapping of  
the remaining keywords. This would allow the user to reduce the excursion  
between 'medium' and 'x-loud' in a user stylesheet without loosing all  
aural styling. A sensible use of '@volume' would be to set its value to  
something higher than 60, but it could be (ab)used for special effects if  
set to a lower value.

Regards,
/c

-- 
[Quote]
"He is old". But she is wrong. It is not age; it is that a drop has  
fallen; another drop.
~~~ Virginia Woolf

Received on Wednesday, 28 July 2004 07:45:49 UTC