Re: [rtcweb] Platforms that support H264 (was: Congratuiations on the Cisco announcement - but we still prefer VP8)

Martin Thomson <martin.thomson@gmail.com> Sat, 02 November 2013 18:27 UTC

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Date: Sat, 02 Nov 2013 11:26:57 -0700
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From: Martin Thomson <martin.thomson@gmail.com>
To: tim panton <tim@phonefromhere.com>
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Subject: Re: [rtcweb] Platforms that support H264 (was: Congratuiations on the Cisco announcement - but we still prefer VP8)
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On 2 November 2013 09:56, tim panton <tim@phonefromhere.com> wrote:
> Last time I looked, it seemed you couldn’t use the
> Apple supplied (hardware accelerated) h264 library for realtime encode/decode and
> it wasn’t at all clear to me that the hardware encoder licence covered any soft implementation of h264 we
> added.

That is my understanding also.  It's the weekend, so I won't be able
to get a fixed answer, but I believe that Skype uses a largely
software-based implementation of H.264 on iOS devices.  It's not that
there isn't hardware acceleration on the device, it's that the APIs
that are made available to applications do not include a way to access
those functions.