Thread: Hd Bandwidth ?
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Old 07-05-2008, 06:13   #9
Losttheplot
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Re: Hd Bandwidth ?

Quote:
Originally Posted by SMHarman View Post
Thats a lot of Bandwidth for BBC HD when you consider HD DVDs run at a maximum of 30Mbit/s
Thats MPEG2 for you, HD requires a lot of bandwidth! As Virgin are encoding a single channel and its MPEG2 HD then theres no room to stat mux, so they have to use CBR.

A single qam64 channel carries just over 38Mb/s so its not that much really, still plenty of room for a few SD channels.

Not sure what level and profile is typically used for HD DVD's - but level 4 for main profile defines a max of 20Mb/s - level 4.1 at main profile allows upto 50Mb/s to be used. Also bear in mind Virgin encode realtime with effectively a single pass best effort encode, DVD's are encoded non-realtime and for difficult scenes the encoding can be tweaked to provide the best results on a scene by scene basis.
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