[tig] HDnet You gotta read this!!!
Fri Apr 2 21:22:38 BST 2004
James DeLuca here to eat his words:
> And, yes I know there's no HDTV 24 frame transmission standard,
Hmmm. I might well be wrong, but I thought that the ATSC spec DID
include a 24 fps mode. Was this killed off in a later revision?
Sorry, that's what I get for shooting-from-the-hip. I know the 24psF format was added to a tape machine after the 60i was, but haven't looked CLOSELY at a Table-3 chart in a while. We almost exclusively master in 23.976psF (for you audio folk), but haven't ever heard talk of broadcasting at that frame rate.
You'd think those cable co's trying to squeeze every last bit of compression out of their source signals to carry more data might actually do this. Come to think of it, our DVD authoring staff has told me the MPEG2 compression system actually does this. They flag the 3rf field and don't encode it, having the decoder read the flag and duplicate the first field to reconstitute the 3:2 sequence. I hope I didn't just do it again. I bet someone's gonna say "yup, they do that today for the ATSC 60i MPEG encode in them thar Tandberg encoders".
Okay, but the displays still show 60i instead of 24P. But the flicker...
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