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Re: Hi all.

From: Chris Lilley <chris@w3.org>
Date: Mon, 10 Dec 2012 22:38:29 +0100
Message-ID: <1086673332.20121210223829@w3.org>
To: Chris Rogers <crogers@google.com>
CC: Marcus Geelnard <mage@opera.com>, redman <redman@redman.demon.nl>, Chris Wilson <cwilso@google.com>, "public-audio@w3.org" <public-audio@w3.org>
On Monday, December 10, 2012, 9:19:41 PM, Chris wrote:
CR> The intention for the "automation" methods of AudioParam is that
CR> the parameters values should be *exactly* as they are specified
CR> (with no smoothing/de-zippering).  

That sounds as if you are thinking of smoothing methods that do not pass through the specified points, but pass 'near' them.

There are smoothing methods which guarantee to pass through the specified points (Catmul-Rom curves, for example).

CR> It's important to be able to
CR> specify exact curves to be applied for envelopes, grain windows,
CR> etc.  But, the setTargetAtTime() method provides a convenient way
CR> to achieve de-zippering there, if desired.

The smoothing options should be better specified. For example, linear interpolation will give smooth changes of values between points, but obvious artifacts as one segment changes over to another because linear interpolation only gives C0 continuity.

-- 
 Chris Lilley   Technical Director, Interaction Domain                 
 W3C Graphics Activity Lead, Fonts Activity Lead
 Co-Chair, W3C Hypertext CG
 Member, CSS, WebFonts, SVG Working Groups
Received on Monday, 10 December 2012 21:38:13 UTC

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