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Re: [media] Moving forward with captions / subtitles

From: Geoff Freed <geoff_freed@wgbh.org>
Date: Tue, 16 Feb 2010 07:53:19 -0500
To: Silvia Pfeiffer <silviapfeiffer1@gmail.com>, Philip Jägenstedt <philipj@opera.com>
CC: Eric Carlson <eric.carlson@apple.com>, HTML Accessibility Task Force <public-html-a11y@w3.org>
Message-ID: <C79FFF6F.9F9D%geoff_freed@wgbh.org>
On 2/15/10 4:56 PM, "Silvia Pfeiffer" <silviapfeiffer1@gmail.com> wrote:

Hi Philip,

On Tue, Feb 16, 2010 at 12:04 AM, Philip Jägenstedt <philipj@opera.com> wrote:
> On Mon, 15 Feb 2010 19:29:48 +0800, Silvia Pfeiffer
> <silviapfeiffer1@gmail.com> wrote:
>> On Mon, Feb 15, 2010 at 6:06 PM, Philip Jägenstedt <philipj@opera.com>
>> wrote:
>>> On Mon, 15 Feb 2010 14:41:53 +0800, Silvia Pfeiffer
>>> <silviapfeiffer1@gmail.com> wrote:
>>> We've agreed on the basics for a long time, this is all about finding the
>>> appropriate markup/structure to express it, isn't it? I find my
>>> <track><source> suggestion confusing because <track> actually contains
>>> many
>>> tracks. Also, it makes the nesting mandatory, as <source> cannot be given
>>> as
>>> a direct child to <audio>/<video> as that would conflict with the
>>> resource
>>> selection algorithm. <trackgroup><track> is intended to address both of
>>> these problems.
>> Oh, I didn't believe we would use <source> as the top-level, but it
>> would continue to be track.
>> So, it would be either:
>> <track role="SUB">
>>  <source src="subtitles.en.srt" lang="en">
>>  <source src="subtitles.sv.srt" lang="sv">
>>  <source src="subtitles.fr.srt" lang="fr">
>>  <source src="subtitles.zh.srt" lang="zh">
>> </track>
>> <track role="captions">
>>  <source src="captions.en.srt" lang="en">
>>  <source src="captions.sv.srt" lang="sv">
>>  <source src="captions.fr.srt" lang="fr">
>>  <source src="captions.zh.srt" lang="zh">
>> </track>
>> when we want just one of the sources be chosen as the subtitle track.
>> Or it would be:
>> <track src="caption.en.srt" lang="en" role="CC">
>> <track src="subtitles.sv.srt" lang="sv" role="SUB">
>> <track src="subtitles.fr.srt" lang="fr" role="SUB">
>> <track src="subtitles.zh.srt" lang="zh" role="SUB">
>> if they were all independent and possible to be activated in parallel,
>> just like the grouped tracks above can be active in parallel.
> Regardless of the element names, I think that if a minimized form (where the
> inner element is omitted) is allowed it should result in 4 mutually
> exclusive tracks, as this is quite surely the most common case.

I'm not sure what is the most common use case and maybe Geoff as a
practician can help here.

Is it more common to have a list of alternative text tracks (probably
subtitle tracks) on a video, or is it more common to have a mix of
text tracks (probably of different roles, CC, SUB, TAD, etc) that can
potentially be active together on a video.

These days, when subtitles are available, you'll find that the UI displays a list of languages and a method to activate one at a time.  The attached iphone_subtitles.jpg illustrates how the iPhone/iPod touch handles multiple subtitle tracks.


However, what I'd like is to be able to do is activate, say, Italian *and* German at the same time.  This isn't possible today.

In some cases you might find that an author has added closed captions and audio descriptions to a movie.  In this case, the user must be allowed to activate both tracks at the same time.  Since they're of different roles, this isn't a big deal and, in fact, is already possible.  The attached itunes_bubble_cc+ad.png illustrates how iTunes handles this.


(image/jpeg attachment: image.jpg)

(image/png attachment: image.png)

Received on Tuesday, 16 February 2010 12:54:13 UTC

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