#DTV World
2 messages in this thread
(This is actually for Lou, and is an addendum to your questions)
Lou, my knowledge of the Mac and PC DTV worlds is mostly theoretical, so let me
ask you how one of my perceptions holds up: Mac video adapters are more
expensive because (a) they need to scan-convert, and (b) they usually feature
convolution circuitry which averages each scanline with the next, eliminating
interlace flicker at the cost of decreased sharpness. (For example, one would
expect the pack of horizontal lines in a Mac's top window title bar to look
like a dance club's strobe light on TV; yet, I've seen educational shows where
the computer displays come directly from a Mac desktop, and there is no
flicker. A lower-cost Amiga genlock, in similar circumstances, would give
anyone an epileptic fit)
Blaq!
I suspect your analysis of how the Mac does it is correct – I am pretty sure
that is how Video Vision (Radius) works.. The averaging isn't as bad as it
would appear because the Mac and PC screens are usually 480 lines (at least),
and would be more then NTSC handles effectively, at least as a composite
signal. Lou