Re: Inband styling (was Re: Evidence of 'Wide Review' needed for VTT)

On 26 Feb 2015 06:21, "David Singer" <singer@apple.com> wrote:
>
>
> > On Feb 25, 2015, at 11:19 , Silvia Pfeiffer <silviapfeiffer1@gmail.com>
wrote:
> >
> > Definitely the block should be more backwards compatible, since we
don't try have a mechanism for mutiline metadata headers.
>
> wow, you surprise me.  the parser in the spec says you parse from the
webvtt line to a blank line and treat all that as header material, doesn’t
it?

Yes. It also says that a metadata header consists of a name value pair on a
single line.

> what does it say about blocks that don’t look like cues, such as Notes?

The current parser drops them as invalid cues. So it's an extension
mechanism that we can make use of. It's probably better than inventing a
means for multi line headers that will not be backwards compatible.

Cheers,
Silvia.

>
> >
> > Best Regards,
> > Silvia.
> >
> > On 26 Feb 2015 04:20, "David Singer" <singer@apple.com> wrote:
> >
> > > On Feb 25, 2015, at 9:13 , David Singer <singer@apple.com> wrote:
> > >
> > >
> > >> On Feb 24, 2015, at 18:57 , Philip Jägenstedt <philipj@opera.com>
wrote:
> > >>
> > >> I think I agree with Silvia here, a STYLE block seems more natural
> > >> than putting it in the header. Note that we could still, if there are
> > >> strong reasons, drop any such blocks that come after any cue. It
gives
> > >> us some flexibility with the streaming case, even if we don't use it
> > >> now.
> > >
> > > I don’t mind if it’s a block or part of the header, as long as it has
to occur before the first cue. The point is that at the moment one can
random access into a VTT file (not load it all from the beginning), once
one has the ‘header’.  I don’t want to lose that.  In text, one might lose
cues that have an end time that overlaps where you random access to, but in
MP4 packing we even deal with that.
> > >
> >
> > I forgot to ask: which is the least disruptive to existing
implementations?  Extending the header, or a new block type?  I think all
existing implementations discard header lines until a blank line, don’t
they, so that should be safe.  What about skipping unrecognized blocks? Is
that clear?
> >
> >
> > WEBVTT
> > Style: |
> >   .stuff css style sheet
> > .
> >
> > Then the first note/cue
> >
> >
> > * * * * * *
> >
> > or
> > STYLE
> >   .stuff css style sheet
> >
> >
> > NOTE/cue
> >
> >
> > David Singer
> > Manager, Software Standards, Apple Inc.
> >
>
> David Singer
> Manager, Software Standards, Apple Inc.
>

Received on Wednesday, 25 February 2015 20:45:53 UTC