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Re: Audio-ISSUE-105 (MIDI timestamp resolution): timestamps in MIDI should use High Resolution Time [MIDI API]

From: Jussi Kalliokoski <jussi.kalliokoski@gmail.com>
Date: Fri, 1 Jun 2012 18:22:43 +0300
Message-ID: <CAJhzemXL9Spdk2+=Q3QDbW32CjdHOKmWz9Ma7N8urdHXVVKKTw@mail.gmail.com>
To: Audio Working Group <public-audio@w3.org>
Good catch, thank you! As I planned it, the timestamp should have been a
floating point value, allowing for sub-millisecond precision, but actually
DOMHighResTimeStamp is actually more fit fore this.
I will make the necessary changes to the spec.

Cheers,
Jussi

On Fri, Jun 1, 2012 at 6:16 PM, Audio Working Group Issue Tracker <
sysbot+tracker@w3.org> wrote:

> Audio-ISSUE-105 (MIDI timestamp resolution): timestamps in MIDI should use
> High Resolution Time [MIDI API]
>
> http://www.w3.org/2011/audio/track/issues/105
>
> Raised by: Adam Goode
> On product: MIDI API
>
> The current MIDI API specifies timestamp as a long representing
> "milliseconds from the UNIX Epoch".
>
> For MIDI applications, millisecond resolution is insufficient and can
> cause noticeable jitter.
>
> Using absolute wallclock time is also problematic, as it is subject to
> system clock skew.
>
> The MIDI timestamp should use High Resolution Time (DOMHighResTimeStamp),
> which solves these problems:
>
> http://dvcs.w3.org/hg/webperf/raw-file/tip/specs/HighResolutionTime/Overview.html
>
>
>
>
Received on Friday, 1 June 2012 15:23:13 GMT

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