Quote:
|
Originally Posted by towny
Looks like he's not hosting the images any more.
Proppin - thanks! Things I never knew I never knew! How are these Vertical Blanking Interval lines used to allow a TV to 'lock on' to a picture?
|
Theres timing information in some of them which tells the TV that its the start of a field and whether its an odd or even field etc. The pics wouldn't be very good if the TV couldn't find the top of the fields!
They are also used to pass on analogue teletext, analogue test signals (VITS), the first half of line 23 also signals AFD/Aspect ratio info to your TV.
The horizontally blanked parts of the analogue picture data (sync pulses, and colour burst etc) is also not sent within MPEG. The STB produces the signalling the TV needs.