Re: EME and timed text

On Wed, Apr 3, 2013 at 8:44 AM, David Singer <singer@apple.com> wrote:

>
> On Apr 3, 2013, at 3:00 , Henri Sivonen <hsivonen@iki.fi> wrote:
>
> >  Timed text should not be DRMable just for principled
> > symmetry with video and audio.
>
> There are some cases where people want to supply text tracks 'in
> multiplex' (and meta-data tracks, and so on).  It seems to me that though,
> as you say, we shouldn't spend our time optimizing the EME and MSE for
> other track types, we shouldn't try to stop them working (or ban them from
> these interfaces) just for principled considerations from some people,
> either.
>

There is a difference, though, between the CDM decrypting a multiplexed
text track and simply passing that decrypted text data to the browser and
the CDM being responsible for rendering. We need CDM rendering to be
possible for audio and video, but I am not sure anyone is asking for that
for text. It has a lot of technical implications, as Henri points out.
Given what we've already said in the specification, it seems like scope
creep for this first version.

...Mark


>
>
> David Singer
> Multimedia and Software Standards, Apple Inc.
>
>
>