[rtcweb] On video codec for rtcweb

Stefan Hakansson LK <stefan.lk.hakansson@ericsson.com> Fri, 23 March 2012 11:11 UTC

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Date: Fri, 23 Mar 2012 12:11:26 +0100
From: Stefan Hakansson LK <stefan.lk.hakansson@ericsson.com>
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Subject: [rtcweb] On video codec for rtcweb
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I think most agrees to that it would be advantageous if there could be 
an agreement on mandatory to implement codecs (at least one for audio 
and at least one for video), for interoperability between 
implementations (among other things).

I would like to discuss a bit on mandatory to implement video codec 
support. There are many factors to consider, three of them are:

1. Coding efficiency: As more and more of the available capacity on the 
Internet is consumed by video, I think that codecs that are clearly 
inferior to the state of art regarding compression efficiency should not 
be considered.

2. Implementation status: Another factor to consider is the 
implementation status in end user equipment, and, especially for battery 
powered devices, to what extend platforms have (optimized/HW 
accelerated) implementations.

3. Interoperability with existing services (it can be argued that webrtc 
is a green field, but on the other hand there seems to be a lot of 
people wanting interoperability).

To me, h.264 is a good candidate considering the factors above. It is 
competitive regarding compression efficiency, it is widely implemented 
(in all kinds of devices and platforms) and is the by far mostly used 
video codec currently. Notably, a recent study ([1]) says that h.264 is 
the leading format also for the html video element.

In addition, licensing for h.264 seems straightforward, and the large 
number of implementations in commercial use indicates that vendors do 
not perceive the risk for licensing/patent issues down the road as being 
unacceptable big (this is an observation from the outside; I'm not a 
lawyer and I don't deal with licensing).

So, I propose that h.264 should be mandatory to implement.


[1] http://blog.mefeedia.com/html5-dec-2011