[whatwg] Codecs for <audio> and <video>

[Silvia Pfeiffer]

Hi Ian,

I have just posted a detailed reply on your email to public-html
(http://lists.w3.org/Archives/Public/public-html/2009Jun/0830.html),
so let me not repeat myself, but only address the things that I
haven't already addressed there.


On Tue, Jun 30, 2009 at 2:50 PM, Ian Hickson<ian at hixie.ch> wrote:
> I considered requiring Ogg Theora support in the spec, since we do have
> three implementations that are willing to implement it, but it wouldn't
> help get us true interoperabiliy, since the people who are willing to
> implement it are willing to do so regardless of the spec, and the people
> who aren't are not going to be swayed by what the spec says.

Inclusion of a required baseline codec into a standard speaks more
loudly than you may think. It provides confidence - confidence that an
informed choice has been made as to the best solution in a given
situation. Confidence to Web developers, confidence to hosting
providers, confidence also (but less so, since they are gatekeepers in
this situation) to Browser Vendors.

In my opinion, including a baseline codec requirement into a W3C
specification that is not supported by all Browser Vendors is much
preferable over an unclear situation, where people are forced to
gather their own information about a given situation and make a
decision on what to choose based on potentially very egoistic and
single-sided reasons/recommendations.

In fact, it is a tradition of HTML to have specifications that are
only supported by a limited set of Browser Vendors and only over time
increasingly supported by all - e.g. how long did it take for all
Browser vendors to accept css2, and many of the smaller features of
html4 such as fixed positioning?

I firmly believe that making the decision to give up on baseline
codecs is repeating a mistake made and repeatedly cited as a mistake
on the lack of specification of a baseline format for images - which
is one of the reasons why it took years to have two baseline image
codecs available in all browsers. We could try the other route for a
change and see if standards can actually make a difference to
adoption.


> Going forward, I see several (not mutually exclusive) possibilities, all
> of which will take several years:
>
>  1. Ogg Theora encoders continue to improve. Off-the-shelf hardware Ogg
>    Theora decoder chips become available. Google ships support for the
>    codec for long enough without getting sued that Apple's concern
>    regarding submarine patents is reduced. => Theora becomes the de facto
>    codec for the Web.

This to me is a defeat of the standardisation process. Standards are
not there to wait for the market to come up with a de-facto standard.
They are there to provide confidence to the larger market about making
a choice - no certainty of course, but just that much more confidence
that it matters.


>  2. The remaining H.264 baseline patents owned by companies who are not
>    willing to license them royalty-free expire, leading to H.264 support
>    being available without license fees. => H.264 becomes the de facto
>    codec for the Web.

That could take many years.


> I would encourage proponents of particular codecs to attempt to address
> the points listed above, as eventually I expect one codec will emerge as
> the common codec, but not before it fulfills all these points:

OK, let me try to address these for Theora. The replies for Vorbis are
simply "yes" to each of these points.

>  - is implementable without cost and distributable by anyone
Theora is.

>  - has off-the-shelf decoder hardware chips available
"decoder hardware" for video means that there are software libraries
available that use specific hardware in given chips to optimise
decoding. It is not a matter of hardware vendors to invent new
hardware to support Theora, but it is a matter of somebody
implementing some code to take advantage of available hardware on
specific platforms. This is already starting to happen, and will
increasingly happen if Theora became the baseline codec.

>  - is used widely enough to justify the extra patent exposure
This is a double requirement: firstly one has to quantify the extra
patent exposure, and independent of that is wide uptake.
We are now seeming wide uptake happening for Theora with Dailymotion,
Wikimedia, Archive.org and many small & medium size video platforms
(such as thevideobay, metavid, pad.me) taking it up.
As for the extra patent exposure - with every month that goes by, this
is shrinking. And obviously many players have already decided that the
extra patent exposure of Theora is acceptable, since already three
Browser Vendors are supporting Theora natively.

>  - has a quality-per-bit high enough for large volume sites
Your main argument against Theora is a recent email stating that
YouTube could not be run using Theora. Several experiments with
current Theora encoder version have demonstrated that this statement
was based on misinformation and not on fact. Until I see fact that
confirms that YouTube would indeed be unable to run using Theora, we
have to assume it is myth. Current Theora indeed has a quality-per-bit
high enough for large volume sites.


> On Thu, 22 Mar 2007, Thomas Davies wrote:
>>
>> Having been pointed at this discussion by Christian, I thought I'd let
>> you know a bit more about where Dirac is as a royalty-free open source
>> codec. We're certainly very keen for Dirac to be considered as one of
>> the supported video formats.
>
> It's unclear to me why Dirac hasn't received as close investigation as
> Theora and H.264. I encourage you to approach the browser vendors directly
> and discuss it with them. I expect, however, that the situation is
> basically the same as with Theora (some UAs would be happy to support it;
> others would cite lack of off-the-shelf hardware decoders and an unclear
> patent landscape).

It has been stated that Dirac's performance on low resolution video
(the YouTube-size videos) is relatively poor, while Theora is very
strong in this area. Dirac will, however, become very important when
we will start seeing large resolution video being exchanged over the
Internet. Thus, I can see a future where we now prescribe a baseline
codec for HTML5 being Theora, but in future we may see additional work
being done on this part of the standard to extend it to other
prescribed baseline codecs that will be more appropriate to the
conditions that we will find ourselves in wrt the Web and Internet
bandwidth. No standard is for eternity.


> On Tue, 11 Dec 2007, Dan Dorman wrote:
>> On Dec 11, 2007 9:06 AM, Joseph Harry <jharry at lapcat.org> wrote:
>> > One thing to remember, HTML is created by people who can be bought,
>> > and it is clearly what has happened here.
>>
>> Hey, let's not get carried away. Ian et al. have been working tirelessly
>> and scrupulously on this spec; there's no reason to cast aspersions on
>> anyone's character.
>
> Joseph is right that I can be bought... but sadly for me this has never
> happened with HTML5. :-(  I guess I picked the wrong area to work in if I
> wanted to make money through bribes!

We do standards to better the world - that is our bribe. :-)


> On Tue, 11 Dec 2007, Manuel Amador (Rudd-O) wrote:
>> >
>> > Actually those are pretty much the only reasons being taken into
>> > account here. Sadly, Ogg doesn't keep the Web free of IP licensing
>> > horrors, due to the submarine patent issue -- as Microsoft experienced
>> > with MP3 and with the Eolas patent over the past few years, for
>> > instance, even things that seem to have well-understood patent
>> > landscapes can be unexpectedly attacked by patent trolls.
>> >
>> > This does suggest we need patent reform, but in practice this is out
>> > of scope for HTML5's development. We can't design our spec on the
>> > assumption that the patent system will be reformed.
>>
>> Interesting.  Finally patents have brought free multimedia innovation to
>> a standstill.  Two quite long paragraphs to say "we admit defeat".
>
> No, that was just a tactical withdrawal. This e-mail here is the one that
> admits defeat. :-)

First rule of standards: never give up!


> On Thu, 13 Dec 2007, Shannon wrote:
>>
>> Ian, are you saying that not implementing a SHOULD statement in the spec would
>> make a browser non-compliant with HTML5?
>> Are you saying that if a vendor does not implement the OPTIONAL Ogg support
>> then they would not use HTML5 at all?
>
> No, I'm just saying that there's not much point requiring a codec unless
> everyone implements it. We don't gain anything saying "you can do Theora,
> or you can do something else, you know, whatever you feel like".

Unfortunately, your current defeat is doing exactly that: giving the
message to do whatever you feel like. Including a Theora prescription
and having it only partially supported with at least give a large part
of the world an interoperable platform and that's all HTML has
traditionally been. HTML has not managed to replace word processing
formats, or pdf. Proprietary formats will continue to be used no
matter what. But if we want to use a compatible format, at least the
spec has made the decision for us on what that format is.


Best Regards,
Silvia.