24p and Panasonic AG-DVX100 and AJ-SDX900 camcorder support in Vegas and DVD Architect Software
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Questions and Answers
What do “i” and “p” stand for in 24p, 60i, 25p?
The “p” stands for “progressive” or full frames, where every pixel in the frame represents the same instant in time,
just like a frame of film. The “i” stands for “interlaced,” a form of video where half of the scan lines (every other
one) represent a moment in time halfway between frames. Each half-frame is called a field. 30p and 60i represent the
same number of lines per second, but 30p has 30 whole frames per second and 60i has 60 fields (half frames) per
second. A typical CRT television displays the first set of scan lines and then the second set. It does this whether the
video is progressive or interlaced. Newer televisions and projectors can do “line doubling” and can draw a whole
frame at a time. All of these progressive displays can deinterlace 60i material (with various levels of success), and
many can do 2-3 pulldown removal to retrieve 24p video from 60i (a superior method of creating progressive frames
from interlaced sources if it had pulldown inserted to begin with).
Should I be using 24p project and render formats for non-24p source video?
Typically, no. These templates should only be used for 24p source material. If used with 60i or other source material,
Vegas will do frame-rate conversions, and the result will not have the 24p “look.” However, it is possible to convert
your 60i material to 24p with reasonable success (see next question).
Can I convert video shot at 60i to 24p?
Follow these steps to convert 60i video shot with a regular camcorder to 24p. There will be some loss of vertical
resolution or other artifacts.
1.
In the Project Properties dialog, set the template to “NTSC DV 24p (720x480, 23.976 fps).”
2.
Set the “Deinterlace method” to “Interpolate fields” (for fast-motion clips, but with decreased vertical
resolution) or “Blend Fields” (for clips without fast motion, for increased vertical detail, but with
double edges on moving objects).
3.
Place the 60i clip on the timeline.
4.
Right-click on the clip, select “Switches” and then select “Disable Resample.”
5.
Choose “File > Render” and render to the AVI format with the “NTSC DV 24p (inserting 2-3-3-2
pulldown)” template.
The converted clips can now be used in a 24p project.
Why is pulldown required to store 24p in DV?
The DV standard only specifies how to store 30p/60i NTSC and 25p/50i PAL video. There is no way to store 24p
directly in the DV format. By inserting pulldown, 24p can be stored as NTSC DV in a backward-compatible way
and can be played on any DV device or television.
Why don’t other formats do pulldown removal or insertion?
Most of the other formats can represent 24p material directly, without pulldown. For example, Windows Media 9,
RealMedia, QuickTime, and MPEG-2 for HD all represent 23.976 fps directly. 24p for DVD creates MPEG-2
pulldown flags when using the “DVD Architect 24p NTSC video stream” template.
What about 24p 16:9 anamorphic widescreen?
Vegas and DVD Architect fully support anamorphic 16:9 widescreen. If you are working with 16:9 anamorphic
widescreen 24p DV (perhaps you have the anamorphic adapter for the AG-DVX100 or are shooting widescreen with
the AJ-SDX900), use the “Widescreen” templates in place of the standard templates.
