Chapter 5 FUNCTIONS AVAILABLE WITH TV STANDARD SIGNALS
289
5.4 WSS
5.4.1 Description and specifications
What is WSS (Wide Screen Signaling)?
“WSS (Wide Screen Signaling)” is a system for multiplexing the aspect ratio information of the
images in the vertical sync blanking interval, and sending it.
WSS specifications
WSS supports the following TV signals.
WSS is superimposed onto the composite signals and Y/C signals.
• PAL, PAL-N, PAL-Nc
• SECAM
The aspect ratio information of WSS is superimposed on line 23 of the first field. The WSS waveform
consists of Run-In, Start Code and the 14-bit data. This waveform and the bit allocation are shown
below.
0.5 V± 5%
0IRE
11.0us±0.25us
Line 23
Run-In Start Code 14 Data Bits
01 13Bit
27.4us Video
WSS(Widscreen Signaling)
• Bit3-0: Aspect
Bit
0 1 2 3
Aspect Ratio Full format or Letterbox Position
0 0 0 1 4:3 Full format Not applicable
1 0 0 0 14:9 Letterbox Center
0 1 0 0 14:9 Letterbox Top
1 1 0 1 16:9 Letterbox Center
0 0 1 0 16:9 Letterbox Top
1 0 1 1 >16:9 Letterbox Center
0 1 1 1 14:9 Full format Center
1 1 1 0 16:9 Full format Not applicable
Bit 3 is the parity bit.
• Bit4-13: Other service information (not supported by the VG-870B/871B/873/874)
To Next Page
Loading...
Need help?
General
