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Old 13th April 2006, 11:27   #22  |  Link
2Bdecided
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Join Date: Dec 2002
Location: UK
Posts: 1,673
I'm glad this thread reached a sensible conclusion, because the earlier suggestion that 720 is equivalent to 704 "plus overscan" is simply wrong.

704 is approximately the width of the analogue active picture ( http://lipas.uwasa.fi/~f76998/video/conversion/ gives more accurate values). As explained on that page, samples outside this range (up to 720) are used when sampling analogue video signals to make sure pixels aren't lost at the edge when the sync isn't quite right, and to avoid single pixel transitions from black to picture causing ringing. The extra pixels are outside the 16:9 and 4:3 active picture area.

It seems to me there's no need to crop anything when going from DV to DVD, but there is good reason to crop down to 704 before resizing to a 1:1 PC resolution.

Cheers,
David.
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