Graphics Reference
In-Depth Information
have to deal with the inequity of trying to shove 24 fps of film (or now HDTV)
into 29.97 fps of video.
The 3:2 Pulldown process is actually very simple and only requires a little
remedial math to understand. Here's how it's done:
One second of film equals 24 and one second of NTSC equals 30 (rounded up).
Simplification equates every five frames of NTSC to four frames of film - that is,
the two media are in synchrony every 1/6th second.
So how do you make
four frames of film
equal five frames for
video? Through a
process where one
frame of film is
duplicated across two
frames of video
utilizing video's
interlaced fields to
split the shared frame.
Look at the illustration
at right. Notice how
frame 1 of the film clip
becomes interlaced
with frames 0 and 2 to
create the frames
required to extend
four frames of film into
five frames of video.
The term '3:2' is
derived from this
process of frame interlacing, keeping three frames 'whole' or transferred directly
and two 'split' or interlaced frames.
Fields vs Frames - A Hot Topic Issue
The Fields vs Frames issue is almost as hot as the Mac vs Windows dispute.
I'm going to give you my angle on this issue: Fields are good, Fields are our
