  Corvus Flaming Tards Since 2003 Premium,VIP join:2003-11-26
| reply to Yoda2009 Re: Current speed?
With digital TV it's something else, we are talking of QUAMS, But 3Gbps is a lot. We can usually put few HDTV on a QUAM but a QUAM cannot handle this now. So basically, if you want to broadcast this you need to span the stream on few frequencies. -- Jesus saves, but only Buddha makes incremental backups. |
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  Xela19115
join:2000-10-06 Richboro, PA
·Verizon FIOS
| Actually it's QAM not QUAM. QAM stands for Quadrature Amplitude Modulation. In one 6 Mhz channel cable company using QAM-256 mode can send 38.8 Mbps of digital video/audio.
Digital video is compressed with MPEG-2 codec. An 1080i HD program can be compressed to a maximum of 19 Mbps (usually it's around 15-16 Mbps). Using QAM-256 mode 2-3 HD channels can be multiplexed. If you use MPEG-4 or WMV9 codecs bandwidth requerement is about 1/2-1/3 of MPEG-2.
1080p HD video if encoded using next generation codecs (MPEG-4) and transmitted using QAM-256 or QAM-1024 -- very doable.
Thing is that there is probably very little noticeable picture quality improvement. If it was like 4096p then of course by all means I want that. But the difference between 1080i and 1080p - is not really worth it. |
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  Corvus Flaming Tards Since 2003 Premium,VIP join:2003-11-26 | Thanks for the info, maybe you can answer this one: I've heard that 1080i is use in movie industry when working on a movie, anything about that? -- Jesus saves, but only Buddha makes incremental backups. |
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  Lumberjack Premium join:2003-01-18 Newport News, VA | It would make sense to capture and render at the highest quality for a big budget film (at least to me). Once complete it can be easily down converted for film, DVD, streams, etc... -- My homies is in da hizouse! |
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  cailyoung
join:2003-06-30 Australia | Most big budget films capture in "academy 2K", or basically 2048P. They might rough-cut with 1080i to make display on a TV easier, but generally on-line footage will be in '2K' image files. The data is stored on D1 tapes. |
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