Apple Final Cut Pro 7 - Manual (Page 1895)

Scanning method Frame rates (fps) Frame size Standard
Progressive 23.98, 29.97
24, 30
25
1920 x 1080 1080p
Interlaced 25 (50i), 29.97 (59.94i),
30 (60i) 1920 x 1080 1080i
1 720p footage recorded at 24, 30, and 60 fps is rare. The 29.97 fps rates are more common because they are compatible
with NTSC equipment.
There are an increasing number of HD tape and file-based formats available. Most HD
formats support only a subset of the options shown in the table above, and most
camcorders and video decks do not support every combination.
Types of Video Signals
Video signals are separated into several channels for recording and transmission. There
are different methods of color channel separation, depending on the video format and
its historical origins. For example, broadcast video devices were originally designed for
black-and-white video, and color was added later. This is still evident in today’s video
formats that break image information into separate black-and-white and color information.
On the other hand, video and image processing on computers is more flexible and
developed later, so a three-color RGB model was adopted instead of a luma-chroma
model.
The luma (black-and-white channel) and chroma (color channels) information can be
recorded and transmitted several different ways in a video signal.
• RGB (Red, Green, Blue): This is the native format for most computer graphics and video
files. This signal is also used inside traditional color CRTs, video cameras, flat-panel
displays, and video projectors. Red, green, and blue signals can be combined to make
any color, as well as grayscale images ranging from black (no signal on any channel)
to white (full signal on every channel). RGB signals do not have a separate luma channel,
because black-and-white signals can be represented by equal amounts of R, G, and B
signals.
• Component YUV: This three-channel Y
′
C
B
C
R
signal has a luma (Y
′
) signal and two color
difference channels (C
B
and C
R
). (The two color difference channels have different names
depending on the particular format but serve a similar function in all formats. Some
common names for different color channels include C
B
, C
R
; R-Y, B-Y; and U, V.)
Component video was invented in the 1950s as a way of making color television signals
compatible with existing black-and-white televisions. Black-and-white televisions could
use the luma signal, and color televisions could convert Y
′
, C
B
, and C
R
back to RGB for
display.
1895 Appendix B Video Formats