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[ttml2] reference scrub

From: Michael A Dolan via GitHub <sysbot+gh@w3.org>
Date: Wed, 11 Oct 2017 17:41:14 +0000
To: public-tt@w3.org
Message-ID: <issues.opened-264674771-1507743658-sysbot+gh@w3.org>
mikedo has just created a new issue for https://github.com/w3c/ttml2:

== reference scrub ==

[GPS] This cite is to an unusual source. But for both UTC and GPS, a reference to the technology is not really all that helpful. It’s only important that one know unambiguously which it is.  The one required bit of information needed by transformation processors is the current in force leap seconds, which is not listed. It turns out that an authoritative normative reference for this has an equally sketchy pedigree (based on a very lengthy discussion in ATSC and CTA over the last 2 months). If you want to enhance the TTML2 with this, let me know and I’ll track down what they decided on. But I think GPS and UTC references are arguably both not essential except for the leap second aspect.

[HTML5] - As we all know, the real spec for HTML5 is at whatwg.org.  Although citing the old W3C Rec is “tidy”, it’s not technically accurate. At least add an informative reference to whatwg and consider what to do longer term.

[SMPTE 12M] – Obsoleted by: ST 12-1:2008 - SMPTE Standard - For Television — Time and Control Code, http://ieeexplore.ieee.org/document/7289820/ 

[URI] – Obsoleted by RFC 3986.  Also, in general, the more helpful RFC URLs are now here, e.g. https://tools.ietf.org/html/rfc3986 


[CMAF] is not yet published and at best is the first of the year.  But the citation in 12.4.1 is a bit misleading.  CMAF just points to 14496-30 and defines some signaling information. I would either remove this or add additional context about why it is relevant.

[ISOBMFF] – Although just a label, the rest of the world uses this acronym to mean specifically, 14496-12.  I’d recommend changing it to “ISO-TT” or something else to avoid reader confusion.

[SMPTE 170M] – Obsoleted by: ST 170:2004 - SMPTE Standard - For Television — Composite Analog Video Signal — NTSC for Studio Applications, http://ieeexplore.ieee.org/document/7291416/ 

[SMPTE 2052-11] – use the full title: RP 2052-11:2013 - SMPTE Recommended Practice - Conversion from CEA-708 Caption Data to SMPTE-TT and add: http://ieeexplore.ieee.org/document/7290363/ 


I think dates/versions are generally essential on normative references with the exception of reference to code point registries. 

Conversely, using undated informative references is OK as long as the title is not likely to change. But to that point, note the SMTPE title changes. Readers can always decide to read newer versions of informative references.

Wherever possible it is good to provide a URL to acquire the citations.

Please view or discuss this issue at https://github.com/w3c/ttml2/issues/457 using your GitHub account
Received on Wednesday, 11 October 2017 17:41:03 UTC

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