[LAD] SMPTE and jackd

Ralf Mardorf ralf.mardorf at alice-dsl.net
Fri May 11 05:26:22 UTC 2012


On Fri, 2012-05-11 at 04:32 +0200, Jens M Andreasen wrote:
> On Tue, 2012-05-08 at 11:21 -0400, Paul Davis wrote:
> 
> > first of all, MTC is not a particularly reliable protocol unless you
> > can dedicate the equivalent of a MIDI cable to it. its data rate gets
> > close to the serial MIDI limit,
> 
> Using MTC quarterframe messages uses no more than 240 bytes/second, less
> than 1/10th of the bandwidth:
> 
> http://en.wikipedia.org/wiki/MIDI_timecode#Quarter-frame_messages

"When the time is running continuously" - Wiki

On Tue, 2012-05-08 at 11:21 -0400, Paul Davis wrote:
"the problem is that many receivers (even if
they do not transmit MTC in the "canonical way"  - i.e. actually
emitting a quarter frame message at a fixed interval) expect to
receive it in canonical form"

"MIDI Time Code

For device synchronization, MIDI Time Code uses two basic types of
messages, described as Quarter Frame and Full. There is also a third,
optional message for encoding SMPTE user bits." -
http://web.media.mit.edu/~meyers/mcgill/multimedia/senior_project/MTC.html

 - Ralf




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