CompuServe Messages

Hi Mark. The purpose of MPEG and MPEG2 is to provide a format for CONSUMER quality digital video DELIVERY. MPEG 1 and 2 are not useful for video editing purposes. A full D1 signal is 27 megabytes PER SECOND. A full D2 signal is 13.5MB, so something's not right with NewTek's or someone else's math if they're claiming to get real D2 off a single hard disk. I dug into all of this for a project I was working on a while back. It gave me enormous appreciation for just how significant a breakthrough Sony's Digital Betacam format is. You get D1 SIGNAL FORMATS out (that is, the 270 megabits per second digital coax I/O) without the incredible cost of a real D1 deck ($80K). The trick of course is compression. This means that if a dub is made from a D1 deck to a Digital Betacam deck, you're not getting an exact copy because it's being compressed onto the tape, but when it's played back, you get the same format as a D1 deck, so its compatible with all the full digital suites. Plus, the Sony compression/decompression is so good that it's basically impossible to see any degradation at all (even with vector scopes) unless you do MANY, MANY dubs. Anyway, getting back to MPEG – the broadcast/cable industry has been seeking a format that's "good enough" for consumer viewing but doesn't require huge bandwidths. This is especially significant because of the gradual move toward giving the consumer the ability to watch anything any time. Fiber optic cable is great, but not unlimited in bandwidth.