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Re: DynamicsCompressorNode.reduction is read-only AudioParam ?

From: s p <sebpiq@gmail.com>
Date: Wed, 28 Aug 2013 23:20:47 +0400
Message-ID: <CAGKuoCW3V-YQs36YQcfjc_3jQFdJhmLwcVB+Hj5-9SUNrOke1A@mail.gmail.com>
To: Paul Adenot <paul@paul.cx>
Cc: "public-audio@w3.org" <public-audio@w3.org>
> We would still make the reduction a read only float, because it would
really be a monitoring value.

If you want to make an envelope follower, an output would probably be more
useful, as you could plug-it directly to a gain for example.


2013/8/28 Paul Adenot <paul@paul.cx>

> If we don't want to make connect work from an AudioParam to an
> AudioParam, and because side-chaining is a specific but very useful
> construct, we could simply add some way to feed in data in the
> CompressorNode, as it's usually done in a side-chain setup: input
> channel 0-x, sound data to be compressed, input channel (x+1)-z, sound
> data that determine the compression level.
>
> We would still make the reduction a read only float, because it would
> really be a monitoring value.
>
> I think this would address the need, be easy to implement/use, and match
> the behaviour of DAWs.
>
> Paul.
>
> On 28/08/2013 18:37, Chris Wilson wrote:
> > Incidentally, I believe the reason is related to side-chain compression;
> > I'd had a conversation with Chris about this a while ago, and his take
> > was that sidechain compression could be done by assigning the .value of
> > a gainNode.gain to the AudioParam output of reduction.  This does not
> > work (IIRC) in Blink/webkit, and AFAIK, nowhere else do you assign
> > audioparam.value to an audioparam and expect it to make a
> > connect()ion-like connection.
> >
> > I do think we must design sidechain compression into the
> > DynamicCompressor before we finish off v1, so I'd like to consider that
> > together with this change.  Sidechain (ducking, de-essing, etc) is
> > incredibly common.
> >
> >
> > On Wed, Aug 28, 2013 at 9:29 AM, Ehsan Akhgari <ehsan.akhgari@gmail.com
> > <mailto:ehsan.akhgari@gmail.com>> wrote:
> >
> >     This has been discussed in
> >     <
> http://lists.w3.org/Archives/Public/public-audio/2013AprJun/0181.html>,
> >     and we agreed that it should be a readonly float.  Paul, can you
> >     please make that change, if nobody objects?  I'd like us to fix
> >     Gecko based on that as soon as possible if we change the spec here.
> >
> >     --
> >     Ehsan
> >     <http://ehsanakhgari.org/>
> >
> >
> >     On Tue, Aug 27, 2013 at 10:30 AM, s p <sebpiq@gmail.com
> >     <mailto:sebpiq@gmail.com>> wrote:
> >
> >         Hi,
> >
> >         DynamicsCompressorNode.reduction is specified to be a monitor
> >         value, so read-only, but the interface says it's an AudioParam
> >         (
> https://dvcs.w3.org/hg/audio/raw-file/tip/webaudio/specification.html#DynamicsCompressorNode-section
> ).
> >         So my question is what is the point in having a read-only
> >         AudioParam?
> >
> >         Sebastien Piquemal
> >
> >
> >
>
>
>
>
Received on Wednesday, 28 August 2013 19:21:14 UTC

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