Re: [rtcweb] Video codec selection - way forward

Maik Merten <> Tue, 19 November 2013 09:08 UTC

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Date: Tue, 19 Nov 2013 10:09:18 +0100
From: Maik Merten <>
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Subject: Re: [rtcweb] Video codec selection - way forward
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I'm sure the prospect of implementing H.261 is not a desirable one but I 
wonder if

  - implementing the codec of "the other codec camp" is more desirable
  - the end-users will appreciate spuriously failing video calls

Basically this boils down on what the question is. "Who enjoys 
implementing H.261?" clearly will be answered as "nobody". However, "who 
can live with the inconvenience of implementing H.261 for the sake of 
interoperability and accessibility" may be answered differently.

It would, of course, be preferable if H.261 can be substituted with a 
higher performing alternative, although I guess the set of codecs with a 
universally accepted status as "no worries regarding IPR or licensing" 
is limited.


Am 19.11.2013 01:07, schrieb David Singer:
> It's an interesting idea, but the quality of H.261, the availability of decent implementations, and its (functional) restrictions may mean that people are very loath to spend (waste) engineering time on it.  Is this a MUST that would, in fact, get respected?
> On Nov 17, 2013, at 11:54 , Maik Merten <> wrote:
>> Hello,
>> just wondering if something like
>> "9. All entities SHOULD support both H.264 and VP8. All entities MUST at least implement one of those. Entities that do not support both H.264 and VP8 MUST implement H.261."
>> has already popped up. My reasoning is that implementations supporting both high performance codecs will always negotiate to use on of those - H.261 should never be relevant there.
>> It appears that all implementors are willing to implement either H.264 or VP8 (but not necessarily both). This obviously means that negotiation failure regarding a high-performance codec is a possiblity. In this case H.261 is actually useful so that basic video calls can still be established (for instance, I guess deaf people may always appreciate a video connection, as long as sign language can be transmitted).
>> Maik
>> Am 14.11.2013 12:37, schrieb Jeremy Fuller:
>>> Hi,
>>> Gaining IETF consensus on making it mandatory to support only H.264 or
>>> only VP8 has clearly failed. I would welcome anyone to share their
>>> thoughts on why they believe this situation will change anytime in the
>>> next few years.  Therefore, can I suggest that we remove items 1 and 2
>>> from the list. Hopefully this will speed up the process by focusing
>>> efforts towards gaining agreement on one of the remaining options.
>>> The following alternatives has been proposed:
>>> 1. All entities MUST support H.264
>>> 2. All entities MUST support VP8
>>> 3. All entities MUST support both H.264 and VP8
>>> 4. Browsers MUST support both H.264 and VP8, other entities MUST
>>>     support at least one of H.264 and VP8
>>> 5. All entities MUST support at least one of H.264 and VP8
>>> 6. All entities MUST support H.261
>>> 7. There is no MTI video codec
>>> 8. All entities MUST support H.261 and all entities MUST support at
>>>     least one of H.264 and VP8
>>> Regards,
>>> Jeremy Fuller
>>> _______________________________________________
>>> rtcweb mailing list
>> _______________________________________________
>> rtcweb mailing list
> David Singer
> Multimedia and Software Standards, Apple Inc.