Advanced 2:3:3:2 pulldown, Ab c d – Matrox MXO2 PCIe Host Adapter User Manual

Page 309

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Advanced 2:3:3:2 pulldown

Advanced 2:3:3:2 pulldown

Advanced 2:3:3:2 pulldown was developed as an alternative to the standard
pulldown method for making frame rate conversions in DV video. It is used to
convert 486p @ 23.98 fps video to NTSC (486i @ 29.97 fps) video. This
conversion is used when video footage is acquired by a DV camera at 23.98 fps
and recorded to DV tape with the recorder set for advanced pulldown (called
24PA or 24P Advanced mode on some devices). Advanced 2:3:3:2 pulldown
differs from standard 2:3 pulldown in that the two middle frames of the video
sequence are each converted to three video fields.

The following diagram demonstrates the process:

Advanced 2:3:3:2 pulldown is accomplished by representing the first frame of
progressive video (frame

A

) as two fields of video (fields

a1

and

a2

), the second

frame (frame

B

) as three fields of video (fields

b1

,

b2

, and

b3

), the third frame

(frame

C

) as three fields (fields

c1

,

c2

,

and

c3

), and the fourth frame (frame

D

) as

two fields (fields

d1

and

d2

).

A

B

C

D

a1

a2

b1

b2

b3

d1

c3

c2

c1

d2

P

rogressive frames @ 23.98 fps

Video fields @ 29.97 fps

Frame

A

Frame

C

Frame D

Frame B

Frame E

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