Re: MIDI data with timestamps in the future?
Re: MIDI data with timestamps in the future?
- Subject: Re: MIDI data with timestamps in the future?
- From: Bill Stewart <email@hidden>
- Date: Thu, 25 Jul 2002 18:48:39 -0700
We have a new API in Jaguar that should alleviate this considerably (and to
follow on from my previous post is highly recommended methodology for Java
because of the overhead incurred in crossing from C to Java)
There's a AUMIDIController API that will allow you to "connect" a MIDI
Endpoint to an AudioUnit (or MusicDevice) including the ability for a
vanilla audio unit to provide a mapping between incoming MIDI and set
parameter calls.
It won't do the scheduling, but it will do all of the parsing of MIDI
data...
on 7/23/02 1:20 AM, Pete Yandell wrote:
>
According to the documentation for MIDISend:
>
>
"Events with future timestamps are scheduled for future delivery"
>
>
Unfortunately this doesn't seem to be true in practice.
In Jaguar we've fixed some of this...
A virtual destination will receive scheduled data from the MIDIServer (this
was NOT true in 10.1)
From the MIDIServer's point of view, a virtual source is just like receiving
midi in data from a driver - so that is done "now" - just as midi data that
is received from say a keyboard - would behave. There is no scheduling
applied to data flowing in this direction because its already happened at
some time in the past anyway.
That should answer your questions I think.
Bill
>
I've had a report from somebody using CoreMIDI to send data through a
>
virtual endpoint to my application (SimpleSynth) that packets injected
>
with future timestamps are played immediately by SimpleSynth.
>
Internally SimpleSynth simply passes incoming MIDI data to the built-in
>
synth audio unit.
>
>
My question is this: whose responsibility is it to actually delay the
>
packets? I would have thought it was up to CoreMIDI. If I have to do
>
it myself, my app gets a lot more complicated...I would have to add
>
parsing of MIDI data and some fairly complex scheduling code.
>
>
I'm currently trying to put together a complete test...I'll post again
>
when I have.
>
>
Pete Yandell
>
http://pete.yandell.com/
>
_______________________________________________
>
coreaudio-api mailing list | email@hidden
>
Help/Unsubscribe/Archives:
>
http://www.lists.apple.com/mailman/listinfo/coreaudio-api
>
Do not post admin requests to the list. They will be ignored.
--
mailto:email@hidden
tel: +1 408 974 4056
__________________________________________________________________________
"...Been havin' some trouble lately in the sausage business," C.M.O.T.
Dibbler replied.
"What, having trouble making both ends meat?"
__________________________________________________________________________
_______________________________________________
coreaudio-api mailing list | email@hidden
Help/Unsubscribe/Archives:
http://www.lists.apple.com/mailman/listinfo/coreaudio-api
Do not post admin requests to the list. They will be ignored.