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Re: Missing information in the Web Audio spec

From: Robert O'Callahan <robert@ocallahan.org>
Date: Thu, 17 May 2012 09:46:46 +1200
Message-ID: <CAOp6jLb2tKxCb6vrzrBKE_ntMondKtgR3GQVJ+0uEB5Pi0r3xQ@mail.gmail.com>
To: Chris Rogers <crogers@google.com>
Cc: Philip Jägenstedt <philipj@opera.com>, public-audio@w3.org
On Thu, May 17, 2012 at 8:32 AM, Chris Rogers <crogers@google.com> wrote:

> On Wed, May 16, 2012 at 1:25 PM, Robert O'Callahan <robert@ocallahan.org>wrote:
>
>> On Thu, May 17, 2012 at 3:19 AM, Philip Jägenstedt <philipj@opera.com>wrote:
>>
>>> If circular routing is not to be allowed, I quite like the solution in
>>> MSP, to consider that graph blocked. To require throwing an error
>>> synchronously would require checking for loops on every operation :(
>>
>>
>> This example:
>> var node = (new webkitAudioContext()).createGainNode();
>> node.connect(node);
>> doesn't throw in Chrome dev. Chris, how does Webkit handle cycles?
>>
>
> They are allowed.  It's common in audio processing graphs to have delays
> with feedback and they are commonly used in musical audio production.  As a
> simple example, consider a delay with a low-pass filter in the feedback
> loop which would be something like the beloved "Echoplex" tape delay:
> http://en.wikipedia.org/wiki/Echoplex
>

Ah, thanks, I should have remembered that. Then resolving ISSUE-24 will
require specification of a processing model that handles cycles. I would
like resolving that to be quite high priority as it will have significant
impact on the architecture of any implementation.

Rob
-- 
“You have heard that it was said, ‘Love your neighbor and hate your enemy.’
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Received on Wednesday, 16 May 2012 21:47:16 GMT

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