High Definition Television

1
High Definition Television
What is HDTV?
Digital signal
Programme source
Transmission
Digital TV

• broadcasting

• aspect ratio 169
• resolution 720/1080
• digital audio

Digital signal
Analog signal
Set-top box (decoder)
Todays TVs

• aspect ratio 43/129
• resolution 525/625

Definition HDTV is 1. An all-digital TV
broadcast signal that delivers a
high-resolution, wide-screen picture and
digital quality audio. 2. A wide-screen TV set
capable of receiving these all-digital signals
and displaying them at full resolution. 3. A
set-top box that will allow normal TVs to receive
these digital signal but not display them at
full width of resolution.
2

• HDTV
• aspect-ratio
• resolution
• bandwidth
• Aspect ratio
• aspect ratio - the ratio width to height of a
  video picture.
• todays TV 43 or 129 (1.331)
• HDTV 169 (1.781)
• motion pictures/movies are shot at 1.851 or
  greater ratio
• Resolution
• sharpnest and clarity of an image
• 1. numbers of horizontal lines
• 2. how signal comes into TV
• i. interlaced (line by line)
• ii. progressive (all lines at once)