On Apr 11, 2013, at 3:54 PM, Silvia Pfeiffer <[email protected]> wrote:
> I think Eric is right - we need a new @kind="forced" or > @kind="forcedSubtitles" value on track elements, because they behave > differently from the subtitle kind: > * are not listed in a track menu > * are turned on by browser when no other subtitle or caption track is on > * multiple forced subtitles tracks can be on at the same time (see discussion > at https://www.w3.org/Bugs/Public/show_bug.cgi?id=21667 ) > > I only wonder how the browser is meant to identify for which language it > needs to turn on the forced subtitles. If it should depend on the language of > the audio track of the video rather than the browser's default language > setting, maybe it will need to be left to the server to pick which tracks to > list and all forced tracks are on, no matter what? Did you have any ideas on > this, Eric? > I believe it should be the language of the video's primary audio track, because forced subtitles are enabled in a situation where the user can presumably understand the dialog being spoken in the track's language and has not indicated a preference for captions or subtitles. eric > > On Fri, Apr 12, 2013 at 4:08 AM, Eric Carlson <[email protected]> wrote: > > In working with real-world content with in-band subtitle tracks, I have > realized that the spec doesn't accommodate "forced" subtitles. Forced > subtitles are used when a video has dialog or text in a language that is > different from the main language. For example in the Lord of the Rings, > dialog in Elvish is subtitled so those of us that don't speak Elvish can > understand. > > This is only an issue for users that do not already have subtitles/captions > enabled, because standard caption/subitle tracks are expected to mix the > translations into the other captions in the track. In other words, if I > enable an English caption track I will get English captions for the dialog > spoken in English and the dialog spoken in Elvish. However, users that do not > typically have subtitles enabled also need to have the Elvish dialog > translated so subtitle providers typically provide a second subtitle track > with *only* the forced subtitles. > > UAs are expected to automatically enable a forced-only subtitle track when > no other caption/subtitle track is visible and there is a forced-only track > in the same language of the primary audio track. This means that when I watch > a version of LOTR that has been dubbed into French and I do not have a > subtitle or caption track enabled, the UA will automatically show French > forced subtitles if they are available. > > Because forced subtitles are meant to be enabled automatically by the UA, it > is essential that the UA is able to differentiate between "normal" and > "forced" subtitles. It is also important because forced subtitles are not > typically listed in the caption menu, again because the captions in them are > also in the "normal" subtitles/captions. > > I therefore propose that we add a new @kind value for forced subtitles. > "Forced" is a widely used term in the industry, so I think "forced" is the > appropriate value. > > eric > > >
