Objections to Netflix Proposal from 2017-11-15

Dear all,

As clarification seems to be needed in terms of W3C process:  IRT objects to
the Netflix proposal made by Cyril Concolato on 2017-11-15.

XML Attribute vocabulary that have been established in standards for years
like linePadding and multiRowAlign should only be defined in their current
namespace (in this case "urn:ebu:tt:style"). The attributes local names and
their semantics should not be copied to another namespace (in this case
"http://www.w3.org/ns/ttml#styling"). Especially for systems that are
implemented into hardware like TV sets or set top boxes it takes a lot of
time until market penetration is reached. System manufacturers therefore
need to trust in the stability of standards over a long period.

To signal now deprecation of these attribute vocabulary and to just
re-define them in another namespace disrupt successful market adoption of
TTML standards and will raise doubts in the stability of TTML related
standard activities.

This may be especially true for the attribute fillLineGap. The standard that
defines that attribute (IMSC 1.0.1) will (hopefully) reach REC status in
2017. If the publication of the next version of IMSC (version 1.1) is
already deprecating this attribute in the same year and will define it in
another namespace this gives a strong impression of a volatile standard
activity.

We do not see any technical reason to keep all vocabulary commonly used in a
TTML document in namespaces defined by TTML 1 and 2. In recent
implementations we have not seen problems to use namespaces defined by
EBU-TT-D, IMSC and TTML in one document.

Best regards,

Andreas

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Andreas Tai
Production Systems Television IRT - Institut fuer Rundfunktechnik GmbH R&D
Institute of ARD, ZDF, DRadio, ORF and SRG/SSR Floriansmuehlstrasse 60,
D-80939 Munich, Germany

Phone: +49 89 32399-389 | Fax: +49 89 32399-200
http: www.irt.de | Email: tai@irt.de
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registration court&   managing director:
Munich Commercial, RegNo. B 5191
Dr. Klaus Illgner-Fehns
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Received on Thursday, 30 November 2017 16:42:42 UTC