[whatwg] on codecs in a 'video' tag.

Maciej Stachowiak mjs at apple.com
Mon Apr 2 11:12:07 PDT 2007


On Apr 2, 2007, at 5:03 AM, Gervase Markham wrote:

> Maciej Stachowiak wrote:
>> Reasons Apple would like MPEG4 + H.264 + AAC to be the preferred  
>> codec stack
>> ----------
>> - We already need to support these for video production and  
>> consumer electronics (so no extra patent cost to us)
>
> I don't understand this point. There's no extra patent cost in  
> supporting Theora. (See below for submarine patents.)

What I mean is that unlike the case for other browser vendors, it  
won't cost us anything in patent license fees.

>
>> - Every extra codec we ship is incrementally more submarine patent  
>> risk (which could cost us hundreds of millions or billions of  
>> dollars)
>
> But this is not just true of video codecs. Is Apple planning to  
> stop shipping new software and improvements in Mac OS X because  
> some of it may be patented?
>
> If you are concerned about submarine patents, I suggest that "not  
> shipping stuff" is not a sustainable strategy to counter them.

Obviously there is a tradeoff. Video codecs are a much more patent- 
prone area than many other areas of software.

>> - They are technically superior to Ogg (seekable container format,  
>> significantly better bitrate for video)
> > - They are competitive with likely next-generation proprietary video
> > formats
>
> I'll let others comment on this. But I would note that JPEG2000 is  
> technically superior to JPEG, but hasn't been widely implemented  
> due to patent issues.

And due to the fact that JPEG is already universally deployed and  
good enough for most uses.

>
>> - They are an open ISO standard (patents notwithstanding)
>> - They are widely available in hardware implementations which we  
>> can use in our Consumer Electronics devices
>> - They have been chosen as a standard for 3G mobile devices, HD- 
>> DVD, Blu-Ray, HDTV broadcast, etc
>
> All of which ship in countable units, and (where applicable) don't  
> run free software.
>
>> Reasons Mozilla would like Ogg + Theora + Vorbis to be the  
>> preferred codec stack
>> ----------
>> - All known patents are royalty-free, so no need to pay $5 million  
>> to MPEG-LA
>
> The problem is not that it's $5 million, it's that the amount is  
> unknown and unmeasurable. They have no "fixed fee above a certain  
> number of units" licensing policy. And even if they did, a Mozilla  
> license wouldn't cover other members of that community.

Actually, they do have a license cap, and I overestated it. See  
<http://www.mpegla.com/m4v/m4v-agreement.cfm>. It's only $1 million  
for "Decoders sold to end-users and/or as fully functioning for  
PCs." (This document could be out of date.)

It's not immediately clear to me that a Mozilla license would not  
cover redistribution, for instance the license fees paid by OS  
vendors generally cover redistribution when the OS is bundled with a  
PC. I think someone would have to look at the legal language of the  
agreement to see if it covers redistribution.

>> - Implementation would clearly be freely redistributable by third  
>> parties (the situation might be unclear if only Mozilla paid for a  
>> patent license)
>> - No demand for use fees for commercial distribution in this format.
>
> Let me add other reasons why Mozilla (for whom, again, I am not  
> speaking) might want to specify Theora/Dirac:
>
> - They have a strong commitment to interoperability

I don't think Theora (or Dirac) are inherently more interoperable  
than other codecs. There's only one implementation of each so far, so  
there's actually less proof of this than for other codecs.

> - They appreciate that there are a wide variety of distribution  
> models;
>   for browsers, and do not want to choose technologies which work only
>   for some of those;

Unfortunately, Ogg does not work for some browsers either.

> - If they think a royalty-free patent policy for standards is a good
>   idea in one place (the W3C) then they think it's a good idea
>   everywhere.

The problem is that the main standards bodies for video (such as the  
ISO) do not have the same norms about RF vs. RAND patent licensing as  
the W3C.


>
>> We think your reasons are strong and worthy of respect. That is  
>> why we are not trying to force our codec preference on you, but  
>> rather propose to leave this issue open. We ask you to respect our  
>> reasons as well, rather than trying to force us to go along with  
>> your codec preference.
> >
>> I think achieving broader interoperability will require us to find  
>> ways around this impasse, rather than bludgeoning each other until  
>> one side caves.
>
> So, just to be clear: you believe interoperability is best promoted  
> by having no codec specified in the spec?

I think if the spec mandates a single codec, that part of the spec  
will be ignored by at least some parties.

>
>> One possibility would be an open API for codec plugins that will  
>> work in <video>/<audio>, then user availability of codecs is not  
>> directly tied to browser choice and codecs can compete in the  
>> marketplace more freely.
>
> You and I both know that this would result in dominance for  
> whatever codecs got shipped by default on major operating systems.  
> Content producers will not choose codecs for 5 or 10% better  
> quality or bitrate, they will choose them for user convenience -  
> because if their site is harder to use than their competitors,  
> they'll fail.

Isn't this basically admitting that Ogg Theora would fail in the  
market if not legislated in the spec? Still, I would not be so sure  
of your conclusion. The bitrate differences among current codecs have  
a range of 2x or 4x, not just 10%. Also, Mozilla supporting Ogg would  
probably carry more weight than Safari supporting Mac OS X, since  
default or not, it has greater overall use share.

> As codecs are binary components, the site wanting to use foo-codec  
> would need to provide versions of it for every operating system  
> they planned to support. For Linux, that would be rather  
> complicated, to say the least. They might not even bother offering  
> it for Mac, or Mac PPC. This would discriminate against operating  
> systems with smaller market shares.
>
>> Another possibility would be to get MPEG-LA to change licensing  
>> terms somehow.
>
> I'm sure that any help Apple would be able to give in this area  
> would be much appreciated. How do you suggest we begin?

One good first step might be for someone to obtain a copy of the  
existing license terms and determine how they would apply to a freely  
redistributable product.

>
>> Yet another possibility is that one codec stack will become so  
>> popular that all parties will feel compelled to implement it  
>> despite their reasons against.
>
> You again assume that only recalcitrance prevents some parties  
> implementing any particular codec stack. As I understand the  
> situation, Firefox would have to stop being free software in order  
> to ship an MPEG4 implementation.

I don't think that is true, but it would depend on the details of the  
MPEG-LA license agreement. Also, at most the MPEG4 implementation  
would not be free software, this would not have to affect the rest of  
Firefox.

Regards,
Maciej






More information about the whatwg mailing list