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[Bug 17400] (AudioGainScale): AudioGain scale underdefined

From: <bugzilla@jessica.w3.org>
Date: Tue, 12 Jun 2012 14:18:59 +0000
To: public-audio@w3.org
Message-Id: <E1SeRvv-0002tr-Ee@jessica.w3.org>
https://www.w3.org/Bugs/Public/show_bug.cgi?id=17400

Philip J <philipj@opera.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|RESOLVED                    |REOPENED
                 CC|                            |philipj@opera.com
         Resolution|FIXED                       |

--- Comment #3 from Philip J <philipj@opera.com> 2012-06-12 14:18:58 UTC ---
The question was answered (output = input * gain) but no normative requirements
on implementations were added. We suggest avoiding phrasing like "will" or
"is".

A "must" is missing in somewhere in the following:

"Every PCM audio sample in the input is multiplied by the gain parameter's
value for the specific time corresponding to that audio sample. This multiplied
value represents the PCM audio sample for the output. 

The number of channels of the output will always equal the number of channels
of the input, with each channel of the input being multiplied by the gain
values and being copied into the corresponding channel of the output."

They could also be replaced by something like "output[t] = gain[t] * input[t]"
given some basic definitions to support it, but that is editorial.

Editorial issues:

"By default, it will take the input and pass it through to the output
unchanged, which represents a constant gain change of 1." can be removed since
it's already defined in the attributes section.

"As with other <code>AudioParams</code>, the <code>gain</code> parameter
represents a mapping from time (in the coordinate system of
AudioContext.currentTime) to floating-point value." can be moved to the
AudioParam section since it is generally true, or removed.

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