Panasonic AV-HLC100E, Руководство по эксплуатации

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For reliable performance, try to ensure the potential upload bandwidth from your system to the net is
around twice the bitrate you choose. You
can
broadcast at a rate closer to your actual ceiling, but reliable
performance cherishes headroom.
Also consider the expected download abilities of your viewers. Ideally, a safety margin 1.5 times the
stream’s bitrate is desirable. This may mean you need to consider using a lower resolution, or lower
framerate for your stream – but doing so when required will generally deliver a smooth result, and is the
wise course. (Nothing inclines viewers to turn away quicker than a stuttering, start and stop stream. See
“Speed Tests” in Section 14.8.1 for some useful resources.)
14.7.2 Streaming Media Providers
Using a commercial streaming media provider (sometimes referred to as a Content Delivery Network, or
simply ‘CDN’) bypasses otherwise high-bandwidth requirements for the encoding computer. When you
have made arrangements for a streaming media provider to distribute your stream, the encoder only
needs enough bandwidth to get a single a/v stream to the provider. All end users connect to the
provider
to view the stream.
Most streaming providers have access to massive bandwidth (and often, with very little notice, they can
scale up your allotment to meet a temporary need.) Since your local bandwidth is really only used for
uploading a single stream, you can send a high quality stream, secure in the knowledge that it will not
degrade as soon as a second viewer attempts to see it.
Other Factors
Other variables to keep in mind when you’re creating video for the web are contrast and motion. During
video encoding for web distribution, a fair amount of video information and detail can be lost. For this
reason, good lighting of your source video is essential.
Also, web streaming doesn’t handle detail, transitions and motion all that well -- so your best shots should
be close up, and without a lot of movement. Too, audio from cameras and camcorders is rarely as good
as that from external microphones. You should at least use a clip-on lavaliere microphone, if not a
directional or shotgun microphone to be sure you record only the audio you really want.