[linux-audio-dev] Interesting USB MIDI master keyboards, do they

[John Lazzaro]

 work with Linux ?

> Tim Goetze <tim at quitte.de> writes:
>
> there's a difference though: the usb 1 ms is jitter, there's no way
> to reconstruct the original timing. this in contrast to midi, where 
> you can extrapolate the exact event time quite well (provided you're
> looking at a stream of mostly isolated events). oh well, most people
> think 1 ms is below human perception limits anyway.

People who are into this topic might want to take a few minutes
to review Appendix C.1 (pp 66-70) of the MWPP draft:

http://www.cs.berkeley.edu/~lazzaro/sa/pubs/txt/current-mwpp.txt

It basically describes the three methods MWPP provides for coding
timestamps onto MIDI commands when packetizing a MIDI stream. The
goal is that whatever your MIDI source is (a MIDI 1.0 DIN jack,
an algorithmic composition program, etc), one of these three
methods will be the right one to capture the timing as best as
can be, into an RTP packet. Feedback is welcome on the topic, 
we're starting to close in "Last Call" for the document, but 
there is still a few months left ... 

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John Lazzaro -- Research Specialist -- CS Division -- EECS -- UC Berkeley
lazzaro [at] cs [dot] berkeley [dot] edu     www.cs.berkeley.edu/~lazzaro
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