Re: Channels and frames
Re: Channels and frames
- Subject: Re: Channels and frames
- From: "john smith" <email@hidden>
- Date: Thu, 27 Oct 2005 12:30:38 +0200
Marc,
I do just want to throw in here that I would encourage you to consider
whether you really need to limit your effect to these configurations.
Thanks for your consideration. What you need to know is that what I'm
creating is a wrapper to a geneic format.
The way we're doing it, the plug-in decides the number of channels (which
can then, for multi-channel plugs, i.e. synths, be set in the interface).
This is to support all platforms. Some of them, for instance Cubase as I
recall, tends to show all outputs, even if not used.
As for effect plug-ins I want to limit them to the configurations I
mentioned, i.e. 1->1, 1->2 and 2->2 and maybe in some cases 2->1. This is
for performance reasons. A dynamic channel count decreases performance too
much IMHO.
If your plugin doesn't have any inter-channel dependencies, or if it
does but they can easily scale to any same number of inputs and outputs,
then I would really encourage you to do that. It's a nice capability of
AU, and personally I feel that too many effects don't do that when they
easily could. And in fact, if that's what you were to do, then you could
forget about this SupportedNumChannels() thing, cuz the default for effect
AUs is to not support the property, and not supporting the property =
saying "I can do any number of channels, as long as the number of inputs
and outputs are equal."
Oh, that's interesting.
But besides the performance thing, some questions arises which I guess could
be called "semantic". For instance, say I have a reverb, and I get 3
channels, what do I do? With 2 channels the answer is obvious, and with 1
channel I *could* (even if I'd prefer not to) make it stereo, and mix it
down the single channel.
So, honestly I feel that such a system is not really too useful. I don't
automatically support surround streams, just by adding extra channels. And,
as said, I feel it hurts performance too much.
Greets,
Michael Olsen
KeyToSound / PhonoXone
This way your effect is not arbitrarily limited to configurations only
compatible with sorta old-paradigm DAW design, rather than working in any
configuration in more flexible hosts, or automatically supporting any sort
of surround stream, etc.
In other words, in my opinion, unless you have some really compelling
reason to restrict your effect to only mono or stereo operation, I think
that you shouldn't.
That, I think, is probably part of why you don't see
SupportedNumChannels() even implemented in any of the SDK example AUs, cuz
optimally you don't want to do that.
AUs have a default format - this is the format of each of the input and
output elements that they have when they are created. auval prints this
out for each AU.
I have no idea what you're talking about, sorry. Formats? My process call
is always receiving floats, right? (when you say "format", I think
thinking bit depth and the like).
In this case, Bill is talking about the format of channel counts (e.g.
1-in / 2-out is a format).
Marc
_________________________________________________________________
Express yourself instantly with MSN Messenger! Download today it's FREE!
http://messenger.msn.click-url.com/go/onm00200471ave/direct/01/
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Coreaudio-api mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden