Re: Can the number of channels produced by an AudioNode change over time?

On Thu, Jan 10, 2013 at 7:32 AM, Chris Rogers <crogers@google.com> wrote:

> Yes, this is the case for nodes such as GainNode.  DelayNode and
> WaveShaperNode are similar in this way.  It all happens transparently
> without the JS developer needing to worry about the details.  I'll try to
> be more explicit in the spec to point out exactly where this happens.  Here
> are some other cases where the number of channels can change, due to other
> causes.


OK, thanks.


> * MediaElementAudioSourceNode, if the .src attribute were set and the
> number of channels were different.
> * AudioBufferSourceNode: if the .buffer is changed to one with a different
> number of channels
> * ChannelMergerNode: if the channels for the inputs, or number of
> connected inputs changed...
>
> As an implementation detail, any necessary re-configuration should
> probably happen in between each "rendering quantum" of each 128
> sample-frame block, and not during the time when the graph is right in the
> middle of processing the block
>

Yeah, there's some subtle stuff that needs to be specced here about when
certain kinds of changes to the graph are allowed to happen. (Which is
related to the still-open-I-think issue about whether changes performed by
script are required to be applied atomically.)

Thanks,
Rob
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