Ulead 1.0 - Manual (Page 178)

13—6 SpruceUp User’s Guide
• Cropped D-1: 704x480 NTSC, 704x576 PAL (matches analog blanking)
• 1/2 D-1: 352x480 NTSC, 352x576 PAL
• SIF: 352x240 NTSC, 352x288 PAL
See the Video Assets topic for more information on MPEG. Also see the Square Pixel Issues
topic for information on resolution issues.
Why NTSC’s 29.97 Frame Rate?
Often referred to as 30 frames per second, adding chroma to the original monochrome
NTSC signal made it necessary to change the rate slightly from its original 30 frames per
second to 29.97fps.
Since NTSC's video frame rate is not exactly 30 frames per second, displayed video time
does not match real time, with the difference becoming larger the longer the movie. The
error is 1.8 frames per minute, which adds up to 3.6 seconds over an hour.
Drop Frame timecode periodically skips frame numbers to force the video time to match real
time. SpruceUp uses a semi-colon between the seconds and frames to indicate drop frame
timecode usage (for example, 00:03:25;15). Non-drop frame timecode uses only colons.
The PAL video standard does not have this problem since there really are 25 frames per
second.
What is 4:2:0 Component Video?
There are several component standards, most dealing with how many chroma samples
there are for each luma sample. 4:2:0 is the standard that must be used for DVD video. A
C
B
and C
R
sample (similar to a B-Y and R-Y, or U and V sample) is taken for every other
luma sample on every other horizontal line. This leads to 2:1 chroma downsampling both
horizontally and vertically.