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Appendices : Video Formats and Bandwidth Page 234
HD Video Standards
HD video systems exist in two main standards. The first one is 1280 pixels x 720 lines. It's also called 1K. The second
one is 1980 pixels x 1080 lines. It's also called 2K. The frame rate may vary from 23.98 fps to 60 fps, leading to very
different results in terms of the bandwidth used.
A 720 HD video at 23.98 fps requires 22,096,303 points per second transmission and a 1080 HD video at 29.97 fps
needs 62,145,792 points per second transmission.
Pixel Aspect Ratio
This is the shape of the individual pixels.
HD video systems use mainly square pixels with aspect ratio equal to 1:1
NTSC uses an aspect ratio of 0.9:1 resulting in a 648 x 480 display.
NTSC wide uses an aspect ratio of 1.2:1 resulting in a 864 x 483 display.
PAL uses an aspect ratio of 1.07:1 resulting in a 768 x 576 display.
PAL wide uses an aspect ratio of 1.42:1 resulting in a 1024 x 576 display.
Note: that wide screen formats don't use a greater number of pixels to produce a larger picture.
Color Sampling
RGB
RGB means Red, Green and Blue. Every pixel is sampled for three values representing Chroma and Luma.