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Re: Assistant Performer

From: James Ingram <j.ingram@netcologne.de>
Date: Fri, 08 Mar 2013 15:13:22 +0100
Message-ID: <5139F202.9050600@netcologne.de>
To: public-audio-dev@w3.org
CC: Chris Wilson <cwilso@google.com>
Hi Chris,

> [...] running status is a way of compressing /multiple/ MIDI messages 
> into one long stream.  At this point, the UInt8Array could only 
> contain the bytes of ONE message in that stream - so it would have to 
> be expanded already.

The penny just dropped.
I've been confusing "Running Status" with "Real Time" messages (1-byte 
messages in Range 0xF8-0xFF), and will have to revise the corresponding 
names in my midiLib library. -- Thanks for your patience.

The docs I'm using say that MIDI devices can send Real Time messages at 
any time, even inside other messages.

As far as I can see, the Web MIDI API draft [1] does not mention Real 
Time messages at all.

Can I assume that
a) Web MIDI applications can both receive and send Real Time messages.
b) In Web MIDI applications, RealTime messages are never received in the 
middle of some other message. [1] Section 8.1 says
> A Uint8Array containing the MIDI data bytes of a single MIDI message

all the best, sorry about the confusion,
James

[1] http://webaudio.github.com/web-midi-api/
Received on Friday, 8 March 2013 14:13:57 GMT

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