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

On Thu, Feb 26, 2015 at 12:13 AM, 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.

What does this mean? The parser consumes all data from beginning to
end as a stream. Perhaps it could be proven that if you seek to a
random point and put the tokenizer+parser in a particular state then
the cues that it will output will be a subset of the cues output for a
sequential parse, but this isn't a property of WebVTT files I've ever
even considered.

I think it would be fine to require style blocks to precede any cues,
but I think I'm maybe missing the actual rationale...

Philip

Received on Thursday, 26 February 2015 02:18:57 UTC