Apple Compressor 3 - Manual (Page 278)

The lower frame rate also has the advantage of requiring fewer frames per second of
video, leading to smaller file sizes. The reverse telecine feature makes it easy to do this.
A B A B B C C D D D A A B B B C C D D D A A B B B C C D D D A A B B C C D D D A A B B B C C D D D A B A B B C C D D B D
A B C D A D A B C D A B C D A B C D A B C D B C
A B C D
A A B B C C D D
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Before (29.97 fps)
After (23.98 fps)
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3:2 Pull-Down Removal
About the Cadence
When film is telecined to NTSC video, it has a constant cadence. This means that the 3:2
pattern is consistent and uninterrupted. It is relatively easy to remove the telecine from
a constant cadence clip since you only have to determine the pattern once.
If you take these telecined clips and edit them as NTSC video, the result will be a final
video file that has a broken cadence with an inconsistent 3:2 pattern. It is much more
difficult to remove the telecine from this clip since you have to constantly verify the
cadence to make sure you don’t inadvertently choose incorrect fields when creating the
23.98 fps video.
The Reverse Telecine feature included with Compressor automatically detects broken
cadences and adjusts its processing as needed.
Other Reverse Telecine Issues
There are a few other issues to be aware of when you use the Reverse Telecine feature.
All Other Frame Controls Settings Are Disabled
Since the goal of the Reverse Telecine feature is progressive 23.98 fps video, all the other
options of the Frame Controls pane are disabled when Reverse Telecine is selected.
278 Chapter 23 Working with Frame Controls