Subject: [AVT] mwpp comments

From: "Martijn Sipkema" <[email-masked]>
Date: Wed, 13 Mar 2002 15:46:55 +0100

mwpp now provides sending ahead of MIDI commands. This enables
a packet to have commands scheduled for a later instance than a following
packet's commands, i.e. the execution times of the commands are not
monotonically increasing. I think normally this is not wanted and the sender
should make sure it sends the commands in timed order. Most applications
do however have events that they are able to send ahead of time and those
that it can only send 'late', e.g. midi through funcionality in a sequencer
application. Could the Z flag in the MIDI command section header be used
to indicate that no delta times are used at all, i.e. it is the immediate
stream
when Z = 0. And otherwise (Z = 1) it is the scheduled stream. For the
scheduled stream a special meaning could than be given to timestamps
that are not increasing; All messages that have an execution time larger
than the last one will have their execution time set to that of the last
command.
Also a MIDI status of 0 could be used to have commands with an execution
time later than the status 0 to have their execution time set to the status
0
command's execution time, e.g. Because running status is allowed in mwpp
only the first command in a packet can be a status 0.
Another solution would be allow unordered events, to have the behavious
undefined or to ingnore them.

--martijn

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