- From: David Singer <singer@apple.com>
- Date: Mon, 16 Sep 2013 14:59:07 -0700
- To: Silvia Pfeiffer <silviapfeiffer1@gmail.com>
- Cc: Cyril Concolato <cyril.concolato@telecom-paristech.fr>, "public-texttracks@w3.org" <public-texttracks@w3.org>
On Sep 16, 2013, at 0:21 , Silvia Pfeiffer <silviapfeiffer1@gmail.com> wrote: > Please note that there are already bugs in the bug tracker for these: > > Language: https://www.w3.org/Bugs/Public/show_bug.cgi?id=20853 > > Kind: https://www.w3.org/Bugs/Public/show_bug.cgi?id=18657 (read the > discussion here, please and re-open with new information) > > All, including Style: https://www.w3.org/Bugs/Public/show_bug.cgi?id=15851 > > And from much earlier: > http://www.w3.org/WAI/PF/HTML/wiki/Media_WebVTT_Changes > > We've also made a start at using such headers in: > https://dvcs.w3.org/hg/text-tracks/raw-file/default/608toVTT/608toVTT.html#metadata-xds > > We have two options now: > > 1. We can continue to keep such metadata out of WebVTT and leave it to > authors to use what they see useful. Since the WebVTT spec allows for > such metadata by skipping over it, groups of useful metadata headers > can be specified by other bodies as needed. > > 2. We can pick a few important metadata headers and include them into > the WebVTT spec. This may be particularly useful for such headers that > are required for stand-alone use of WebVTT (Kind, Language, Label, > Style) and leave the rest to authors / metadata standardising bodies. > > > I still tend towards the second option. me too; at the point several people are doing the same thing but in different ways, that screams "agree and do it in a common way". we should Watch This Space. > > Regards, > Silvia. > > > > > On Thu, Sep 12, 2013 at 7:30 PM, Cyril Concolato > <cyril.concolato@telecom-paristech.fr> wrote: >> Hi all, >> >> WebVTT files are/will be used in environments where there might not be an >> HTML page pointing to it. Some examples are: >> - WebVTT content embedded and multiplexed with video and audio in an MP4 >> file >> - Plain text WebVTT files referenced by an adaptive streaming manifest (DASH >> MPD, HLS playlist, ...) >> >> All embedding environments typically enable marking a track with a language >> (e.g. an audio track) but not all can carry the kind types (subtitles, >> captions, metadata). In order to avoid losing that information in those >> environments, I think the WebVTT file should declare its kind. Also, when >> producing WebVTT files, it should be possible to indicate the language, kind >> or even label in the file itself, to avoid mistakes. >> >> I would like to propose to define standard WebVTT metadata headers, as >> follows: >> - WebVTT metadata header name: kind >> - WebVTT metadata header value: as defined by kind attribute of the track >> element in the HTML 5 specification >> >> - WebVTT metadata header name: language >> - WebVTT metadata header value: as defined by srclang attribute of the track >> element in the HTML 5 specification >> >> - WebVTT metadata header name: label >> - WebVTT metadata header value: as defined by label attribute of the track >> element in the HTML 5 specification >> >> Note that some people are already using non standard name/values for that >> (e.g. >> http://wiki.webmproject.org/webm-metadata/temporal-metadata/webvtt-metadata) >> >> Of course, this introduce redundancy when the embedding environment also >> sets those attributes and might be problematic if the values differ. >> Resolving conflicts should be specified by the embedding environment. In >> HTML, the information in the HTML page should probably have precedence, to >> be able to use a caption track as metadata, if the HTML author wants to. >> >> Comments ? >> >> Regards, >> Cyril >> >> -- >> Cyril Concolato >> Maître de Conférences/Associate Professor >> Groupe Multimedia/Multimedia Group >> Telecom ParisTech >> 46 rue Barrault >> 75 013 Paris, France >> http://concolato.wp.mines-telecom.fr/ >> >> > David Singer Multimedia and Software Standards, Apple Inc.
Received on Monday, 16 September 2013 21:59:26 UTC