Re: [rtcweb] Discussion on codec choices from a developer who doesn't come to IETF

"Timothy B. Terriberry" <> Tue, 08 May 2012 16:48 UTC

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Date: Tue, 08 May 2012 09:48:30 -0700
From: "Timothy B. Terriberry" <>
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Subject: Re: [rtcweb] Discussion on codec choices from a developer who doesn't come to IETF
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Justin Uberti wrote:
> This "SW encoding chews battery" claim is often mentioned, but in a
> video chat, the power draw from the screen and network are often 10x the
> CPU power draw, which is typically < 1W (for ARM). So there is very
> little impact on talk time between HW and SW encode.
> Mobile devices are often limited in terms of what resolutions they can
> encode in software, because they have less overall compute power than
> PCs. In my experience, that is the factor to consider, not battery life.

Even if they could encode higher resolutions, they typically don't have 
the bandwidth to push out HD content at several megabits per second (or 
it would be prohibitively expensive if they did). So I think mobile 
videoconferencing resolutions around 360p are much more realistic, and 
perfectly suitable for software. At this point I'll just refer people to 
the guy who posted here from TI: