interlaced video question for you XV experts
vektor at dumbterm.net
Thu Mar 17 19:18:37 PST 2005
Benjamin Herrenschmidt (benh at kernel.crashing.org):
> Which field comes first in a frame is different between PAL and NTSC
> if my memory is correct.
AFAIK, this is a convention and it depends on how it is being stored,
and has nothing to do with the actual output (you have a 4-field and
8-field sequence for the colour carrier in NTSC and PAL respectively,
but in digital video you don't usually care about that).
In MPEG-2 there is a flag called "top_field_first" which indicates the
parity for each encoded frame.
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