Re: bus count and channel info confusion
Re: bus count and channel info confusion
- Subject: Re: bus count and channel info confusion
- From: Stefan Gretscher <email@hidden>
- Date: Wed, 21 Jul 2004 20:03:53 +0200
Am 21.07.2004 um 04:33 schrieb William Stewart:
7. Audio Effect that processes stereo only, but has a side chain
input that can be mono or stereo.
Input Bus Count: 2, not writeable
Output Bus Count: 1, not writeable
Channel Info: Not possible to describe
Yeah, I think that you just can't do this, though I'm not sure about
that.
I believe this should be described as Reaktor (and Reaktor FX)
describes its channels:
Input Bus Count: 1, writable
Output Bus Count: 1, not writable
Channel Info: { -4, 2 }
Then the host can decide to use either 3 or 4 of the input channels as
the user wants. The AU can easily deal with this situation even if the
host configures this as 4 mono inputs too, I believe.
By formatting the first bus to be stereo input (and output), then I
think the AU is providing a pretty reasonable hint to the host about
its preferred configuration (and some hosts may even decide to use this
as the starting off point when presenting dynamically configurable
AU's).
How should hosts deal in this case with mono in stereo out
configuration?
I would assume that if a plug-in provides a channel info of { -4, 2}
that it
is able to do mono in stereo out. However, there's no guarantee for it
as far as I understood it, and it's not the case in the example.
This is problematic for host like Logic as they would have to try to
initialize
the AU to find out whether it really can do mono in stereo out, which is
increasing startup time.
So it would be great if it could be made sure that a channel info of {
-4, 2}
means that all formats {1, 2} {2, 2} {3, 2} and {4, 2} can be used.
Another possible solution of the problem might be taking the element
parameter into account and going for:
Input Bus Count: 2, not writeable
Output Bus Count: 1, not writeable
Channel Info for element 0 : { 2,2 }
Channel Info for element 1 : { 1,2 } { 2,2}
This ofcourse only makes sense when the bus counts of the AU are not
writeable, otherwise the meaning of the element parameter might be
unclear.
Stefan Gretscher
plug-in development & 3rd party plug-in support
Emagic Soft- & Hardware GmbH
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