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Re: [rtcweb] Support of video with different resolutions

"Cullen Jennings (fluffy)" <fluffy@cisco.com> Thu, 27 December 2012 16:40 UTC

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From: "Cullen Jennings (fluffy)" <fluffy@cisco.com>
To: Gunnar Hellström <gunnar.hellstrom@omnitor.se>
Thread-Topic: [rtcweb] Support of video with different resolutions
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Date: Thu, 27 Dec 2012 16:40:07 +0000
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Cc: "rtcweb@ietf.org" <rtcweb@ietf.org>
Subject: Re: [rtcweb] Support of video with different resolutions
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On Dec 21, 2012, at 4:27 PM, Gunnar Hellström <gunnar.hellstrom@omnitor.se> wrote:

> This is sad. For good usability of video, maintained frame rate is usually much more important than maintained spatial resolution. E.g. for sign language or lip reading usage with a single person in image, a frame rate under 20 fps introduces loss of language contents, and requires the users to try to fill in the gaps by imagination, while spatial resolution reduction down to QCIF causes much less harm to language perception possibilities.

Hmm - I think the trade off is a bit more complicated. The is both a minimum number of pixels for the hand + a minimum frame rate - if you get under either of theses , SL does not work real well. Does anyone have pointers to research that shows what theses  are? I've see this type of study in the past but can't find it.

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