In television technology, widescreen signaling (WSS) is a digital stream embedded in the analog TV signal describing qualities of the broadcast, in particular the intended aspect ratio of the image. This can be used by a widescreen TV or other device to switch to the correct display mode.
Contents
PAL and SECAM Systems
For 625 scan line systems (PAL and SECAM), the signal is placed in line 23. It begins with a run-in code and start code followed by 14 bits of information.
Group 2 (Enhanced Services)
The above settings are related to PALplus.
NTSC Systems
525 scan line systems (PAL-M and NTSC) put the WSS data in lines 20 and 283. A start code consisting of the bits "10" is used, followed by 14 bits of information.
Word 0
b2-b5 all have the value "0".
Word 1
b6-b9 are reserved and all have the value "0".
Word 2
b10-b13 are reserved and all have the value "0".