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I'm looking into the feasibility of using a local server to distribute live video of a conference to delegates in the same room. They would still hear the live audio coming from the speaker, so only the video would be streamed. I was considering a Darwin Steaming Server (a lot of iPhone users to support) and encoding with H.264. My main concern is latency across the network. Even with everything running locally, would there be lip sync issues between the live audio and the 'live' video stream? It feels like there will be problems given the encoding, broadcasting, decoding to be completed, but I've never done any like this before so thought I would check.


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Thre would H.264 is made to be high quality and does do / need look forward (i.e. th enext frames) to know how to encode best. Depending on the exact encoder settings that may be minimized... and you could definitely try to minimize the playback buffer (client side).

I had a similar issue some time ago with Microsoft Streaming Services.

You will have real problem finding something that is real time (less than 0.05 seconds delay) so that people dont really realize that the video is off. Even video conferencing has a lot higher delay - they get away with it by basically having audio and video in sync. Lip sync issues are something that people "get" easily.

I dont think there is any streaming technology around (except some vey prmiitive ones that basically dont really encode) that would not result in some lip sync "funniness". The problem really is that people are very sensitive to that.

I would forget it. Record it for later playback, but use the traditional technologies (beamer etc.) for local playback. Seriously: Dont think too many people will like watching their IPhone for the speaker if they are in the same room already.

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Thanks TomTom, sounds like the technology isn't really there for us yet. I'll keep reading around, but it doesn't look like it's going to be something we can work with. – user38392 Mar 22 '10 at 18:32

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