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Re: MIDI Tracks and Sequences (was [Bug 18764] MIDI messages don't all have a channel, and status should be part of data.)

From: Jussi Kalliokoski <jussi.kalliokoski@gmail.com>
Date: Mon, 10 Sep 2012 13:17:17 +0300
Message-ID: <CAJhzemX6g7ikBTY+NndJvXEAPX1kLjwh5+9YCX_A1dqSfD6heQ@mail.gmail.com>
To: James Ingram <j.ingram@netcologne.de>
Cc: public-audio@w3.org, Chris Wilson <cwilso@google.com>
Hi James,

A side note: the current spec has the notion of MIDIEvent as a DOM event
that occurs when MIDIMessage(s) are received.

The toolkit you're referring to deals both with MIDI files (SMF) and MIDI
devices. Our API is designed to work with just devices, and MIDI devices
are just I/O, there's no notion of high level concepts such as tracks
(although there's channels, but that's already in the spec) or sequences,
unlike SMF does. It would seem a bit weird to me to complicate the spec
with such high-level concepts as we don't even support reading / writing
SMF files, nor do I think we should as the intent of the device is
explicitly to allow communication with MIDI devices.

Cheers,
Jussi

On Mon, Sep 10, 2012 at 12:32 PM, James Ingram <j.ingram@netcologne.de>wrote:

> Hi Chris, all,
>
> Chris Wilson said (apropos Bug 18764)
>
>> I'd like to explicitly ask for MORE feedback from developers
>> using MIDI today on this issue.
>>
> I'm following the Bug 18764 debate very closely, but don't have the
> in-depth knowledge of MIDI's finer points to contribute much to the
> subject.  All I want as a future user of this API is that it is going to be
> succinct, work as efficiently as possible and be clearly documented.
> Whether functions are overloaded or not is not really crucial. If I want to
> use the Web MIDI API, then I'm going to have to learn it one way or the
> other.
>
> But I'd like to open another can of worms: :-)
> The current version of the API [1] supports MIDIMessages and MIDIEvents.
> Would it be possible for it to provide Sequence and Track objects as well?
> I've written my own versions of these for my current project (in
> Javascript), but think there must be people out there who know much better
> how to write them than I do. They are prime targets for optimization. We
> should not all have to re-invent the wheel.
> Interestingly, there are versions of these objects in Leslie Sanford's
> popular C# MIDI Toolkit [2]., so he also seems to have thought that they
> were worth providing.
>
> Any thoughts?
>
> Best,
> James
>
> [1] https://dvcs.w3.org/hg/audio/**raw-file/tip/midi/**
> specification.html#callback-**navigatormidiaccesssuccesscall**
> back-parameters<https://dvcs.w3.org/hg/audio/raw-file/tip/midi/specification.html#callback-navigatormidiaccesssuccesscallback-parameters>
> [2] http://www.codeproject.com/**Articles/6228/C-MIDI-Toolkit<http://www.codeproject.com/Articles/6228/C-MIDI-Toolkit>
>
>
>
>
Received on Monday, 10 September 2012 10:17:48 GMT

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