User Manual

Displaying 24p and 25p Media
1519
Displaying 24p and 25p Media
This section applies to you only if you are working with Standard Definition (SD) formats.
When your Avid editing application captures video that has been transferred from film (or video
shot at 24 fps), it creates 24p media. It creates this media by capturing the video fields, by
dropping extra pulldown fields (NTSC transfers only), by combining (deinterlacing) two fields
for each film frame (A1+A2, B1+B2, and so on), and by storing the fields together as a full
frame. The system always stores media as a fully reconstructed, progressive frame. It is the
construction of this full frame that gives you the flexibility to create multiformat output.
You typically use 25p media when capturing film or video shot at 25 fps. In this case, the system
also stores the media as a fully reconstructed, progressive frame. The difference is that there is
no need for pulldown fields because there is a 1:1 correspondence between the source tape and
the captured frames.
Displaying Media While Editing
When you click the Play button while editing a clip or a sequence (sometimes referred to as Edit
Play), the system separates (interlaces) the progressive frames into fields and does the following:
• On the Source, Record, Playback, or pop-up monitor, your Avid editing application displays
the footage at 23.976 fps, 24 fps, or 25 fps, depending on your project and editing
preference.
n
Choose your preference for playback in the Film and 24p Settings dialog box. For more
information, see “Filtering the Settings List” on page 1340.
• On an NTSC monitor, the system does one of two things:
- If playing at 23.976 fps (audio pulldown ON), the system performs a 2:3 pulldown that
replicates the telecine pulldown, and displays the interlaced media at 29.97 fps.
- If playing at 24 fps (audio pulldown OFF), the system performs a 2:3 pulldown, drops
every 1000th frame in the Client monitor, and displays the interlaced media at 29.97 fps.
• On a PAL monitor, the system does one of two things:
- If playing at 24 fps, the system duplicates two fields per second to display the interlaced
media at 25 fps.
- If playing at 25 fps, the system performs a 4.1 percent speedup, maintains 1:1 transfer of
film frames to video frames, and displays the interlaced media at 25 fps.
For 25p projects, 25 fps is the only playback rate. The playback rate is 1:1 with no speed change.