Re: [office] More on graphics response

[robert_weir@us.ibm.com]

Patrick Durusau <patrick@durusau.net> wrote on 03/13/2009 08:29:16 AM:


> >
> Yes, but your suggestion of "the range 0 (inaudible) to 1 (the current 
> system volume)." would mean that if I already have my "system" volume 
> set to 0 that there would be no sound at all, ever.

That is accurate.

I think what is missing is that there are at least two components to the 
volume that an user actually hears.  There is the volume as set by 
software (0-100%) and the volume set in the hardware, which also varies 
from 0-100% (except for very special systems which go up to 110%).  And 
there is often an intermediate level, in the operating system, that can 
also vary the volume from 0-100%.

The actual output volume is the product of all of these settings.  So in 
fact if you muted the sound at the OS level or the hardware level, then 
you will hear no sound, even if the volume is set to 1 in the software. 

None of this is absolute measures, no dB's or anything like that.  It is 
all relative.

I'd just say the volume set by the software ranges from 0 (muted) to 1 
(maximum), knowing that "maximum" is a system-dependent volume.   We can't 
make assurances greater than that since audio systems vary.  We're not 
writing software for a THX certified playback device. 

Similarly, when we say an RGB value is (255,0,0) we cannot claim that the 
user will actually see pure red, since their monitor may not be calibrated 
correctly, they may be viewing with tinted artificial lighting, they may 
be color blind, etc.  All we can state is the intent expressed by the 
output setting.  With things like sounds and colors we cannot make claims 
on system capabilities or human perceptions.

-Rob